Would the black hole theroy pass this challange?

[snooziums]

Hiya

I am wondering how many "scientific" theories would hold up to the million dollar challenge. For example, no one has been able to prove that black holes exist, worm holes, or even the "string theory." Yet, many scientists still accept them as facts.

I have yet to see a working example of a black hole, or any hard evidence that any exist. So why are there not skeptics for these theories within the scientific community?

Just a thought.

[Gr8wight]

I have yet to see a working example of a black hole, or any hard evidence that any exist. So why are there not skeptics for these theories within the scientific community?


There are.

[saizai]

Also - all evidence for black holes is necessarily indirect.

Hardly the first time in physics y'know.

Do you happen to have a degree in astrophysics and keep up with the latest research? If not, that may be why you haven't seen any evidence.

[Crowbot]

I have yet to see a working example of a black hole, or any hard evidence that any exist.

I'm not allowed to post links yet, but google "einstein eclipse black hole" and click the first result (should be a pbs dot org website). You should also check out the NOVA special(s) on the subject of relativity, they're very informative. There is a very large amount of supporting evidence of black holes.

[drkitten]

I am wondering how many "scientific" theories would hold up to the million dollar challenge.

Relatively few of the cutting-edge ones. The reason that they're cutting-edge is precisely because the evidence is not yet to the point where any damnfool can see it for himself; it requires specialized training and knowledge to interpret.

I suspect that most people -- Randi included -- wouldn't be able to identify a cadaver's appendix if asked, either.

[Crowbot]

I suspect that most people -- Randi included -- wouldn't be able to identify a cadaver's appendix if asked, either.

Thanks drkitten, a quick wikipedia search and I am now exempt from this statement! Hopefully I will never *have* to identify a cadaver's Vermiform appendix though!

[joobz]

Thanks drkitten, a quick wikipedia search and I am now exempt from this statement! Hopefully I will never *have* to identify a cadaver's Vermiform appendix though!

I'm happy that you looked it up, but....
While you now have a good idea where to look, until you actually, first hand see the abdominal cavitity in all of it's gooey, slimey, Night of the living dead, smelly glory...you still probably won't have that much luck in identification.

[saizai]

<-- has actually been to cadaver labs and can identify an appendix

(BTW, doing so is a good way to push one towards vegetarianism. Human muscle looks like beef jerky after dissection and drying out.)

[steenkh]

I am wondering how many "scientific" theories would hold up to the million dollar challenge. For example, no one has been able to prove that black holes exist, worm holes, or even the "string theory." Yet, many scientists still accept them as facts.
The point is that the existence of black holes is not paranormal, so a physicist could never apply for the million if he could their existence.

BTW, there are physicists working on creating tiny black holes here on earth in big colliders. It is considered safe because tiny black holes have a very short life. Still, I hope that their theories are right ...

[Genesius]

I have yet to see a working example of a black hole, or any hard evidence that any exist.

Ever heard of a neat online tool called Google?


Surprising observations of a star swiftly orbiting the cloudy heart of the Milky Way Galaxy have verified with near certainty the existence of a central black hole, a theoretical object that still eludes direct detection.
Astronomers watched the star for a decade, tracking two-thirds of its path around the galactic center. No object has ever before been seen so close to the center of any galaxy, nor has any other object previously been observed making more than a small fraction of its orbital trek around a galaxy.
"Our work proves that there is indeed a supermassive black hole in our own galaxy," said Rainer Schoedel, a PhD student at the Max-Planck Institute for Extraterrestrial Physics (MPE) in Germany.
An international team of astronomers photographed the star as it zoomed around the galactic center at speeds ultimately exceeding 11 million mph (5,000 kilometers per second). Early this year, the star flitted precariously close to the black hole, coming within 17 light-hours, or just three times the distance from the Sun to Pluto.
The observations rule out nearly all other possible explanations for the tremendous amount of matter -- equal to some 2.6 million suns -- packed into a tight spot at the center of our galaxy.

From http://www.space.com/scienceastronomy/blackhole_milkyway_021016.html

[Yllanes]

BTW, there are physicists working on creating tiny black holes here on earth in big colliders. It is considered safe because tiny black holes have a very short life. Still, I hope that their theories are right ...

It is also considered to be safe because much more energetic collisions than we can generate on Earth already occur in the upper atmosphere.

[snooziums]

Ever heard of a neat online tool called Google?
Surprising observations of a star swiftly orbiting the cloudy heart of the Milky Way Galaxy have verified with near certainty the existence of a central black hole, a theoretical object that still eludes direct detection.

In short, no one and no instrument has directly seen a blank hole. SO the chances of a black hole being real are must about par with things like auras and telepathic communication. Sure many arguments can be made, and some indirect evidence (mathematics does NOT count as evidence), but still no hard proof.

[Piscivore]

Human muscle looks like beef jerky after dissection and drying out.

There's very little essential difference.

[Genesius]

In short, no one and no instrument has directly seen a blank hole. SO the chances of a black hole being real are must about par with things like auras and telepathic communication. Sure many arguments can be made, and some indirect evidence (mathematics does NOT count as evidence), but still no hard proof.

BUZZ!! Wrong. With black holes, there is plenty of direct evidence, unlike auras and telepathic communication.

Ever heard of Cygnus X-1? From Wikipedia:
Cyg X-1 is a binary star (http://en.wikipedia.org/wiki/Binary_star) that contains an O9-B0 (http://en.wikipedia.org/wiki/Stellar_classification) supergiant (http://en.wikipedia.org/wiki/Supergiant) (with a surface temperature of 31,000 kelvins) and a compact object (http://en.wikipedia.org/wiki/Compact_object). The mass of the supergiant is approximately 20–30 solar masses (http://en.wikipedia.org/wiki/Solar_mass). The compact object has a mass of 7–13 solar masses; as the largest possible mass of a neutron star (http://en.wikipedia.org/wiki/Neutron_star) can not exceed three solar masses, it is believed to be a black hole (http://en.wikipedia.org/wiki/Black_hole). The X-rays are produced in an accretion disk (http://en.wikipedia.org/wiki/Accretion_disk) that is formed by matter flowing from the supergiant into the black hole. Cygnus X-1 is the brightest persistent source of hard X-rays (http://en.wikipedia.org/wiki/Hard_X-ray) (E (http://en.wikipedia.org/wiki/Kinetic_energy) > 20 keV (http://en.wikipedia.org/wiki/KeV)) on the sky

So unless you can provide another source for those X-ray emissions, that qualifies as hard evidence for the existence of black holes.

[CENOBITE]

I remember reading recently that there has been direct observable evidence of a black hole near to the center of the Milky Way galaxy...

heh, oops edit: I see someone above already stated this.

[Genesius]

In short, no one and no instrument has directly seen a blank hole.

Since the escape velocity of a black hole is greater than c, the black hole cannot be directly observed, although the effects of it's gravity can.

No one and no instrument has directly seen the core of the Earth, either. So I guess the Earth's core has as much chance of being real as does a black hole.

[snooziums]

Ever heard of Cygnus X-1? ... So unless you can provide another source for those X-ray emissions, that qualifies as hard evidence for the existence of black holes.

That same phenomena could be explained as being a dark-energy star (http://en.wikipedia.org/wiki/Dark-energy_star) or a magnetospheric eternally collapsing object (http://en.wikipedia.org/wiki/Magnetospheric_Eternally_Collapsing_Object). Both will work in this case.

Just because something is happening (which there is evidence that something is), does not mean that it has to be one set thing. There are other explanations, and unless one can be recreated, or directly observed, it cannot be proven.

Yes, there is something very powerful there, but that does not mean that that something powerful is a black hole.

[drkitten]

That same phenomena could be explained as being a dark-energy star (http://en.wikipedia.org/wiki/Dark-energy_star) or a magnetospheric eternally collapsing object (http://en.wikipedia.org/wiki/Magnetospheric_Eternally_Collapsing_Object). Both will work in this case.

It could, yes.

But the theoretical evidence backing up the possible existence of such objects is substantially less (and less convincing) than the theoretical evidence supporting black holes.

As medical school students are always being told : "If you hear hoofbeats, think horses, not zebras." If I see the footprint of a big cat in the mountains of Colorado, it's most likely to be from a mountain lion or a cougar, not a Tibetian snow leopard.

But you're right. The evidence we have for black holes is substantially less than would be required to win the paranormal challenge, and for good reason. The claim itself is much harder and more expensive to investigate. In the case of paranormal phenomena -- especially the ones at which the Randi challenge is directed -- no such excuse is possible.

[Genesius]

It could, yes.

But the theoretical evidence backing up the possible existence of such objects is substantially less (and less convincing) than the theoretical evidence supporting black holes.

As medical school students are always being told : "If you hear hoofbeats, think horses, not zebras." If I see the footprint of a big cat in the mountains of Colorado, it's most likely to be from a mountain lion or a cougar, not a Tibetian snow leopard.

<bowing>
I was trying to figure out the right way to say that, and you did it better than I could.

[snooziums]

... existence of such objects is substantially less (and less convincing) than the theoretical evidence supporting black holes.... If I see the footprint of a big cat in the mountains of Colorado, it's most likely to be from a mountain lion or a cougar, not a Tibetian snow leopard. ... The evidence we have for black holes is substantially less than would be required to win the paranormal challenge, and for good reason.

Basically, that is what I was trying to get across. It is known that something powerful in the universe is sucking in lots of matter and energy (even light perhaps), and emitting x-rays. Something very powerful, it would seem.

But can it be proven 100 percent that that something is a black hole? No, not 100 percent. So while the black hole theory is most likely, that does not mean that it is absolute truth.

That is what I was trying to get across.

[Ashles]

The difference here is that there is observable and replicable evidence that something is happening - and there are theories about what that something is.

However the paranormal is the exact reverse of this - theories are generated, but there is no evidence of anything going on that would require these theories to be generated in the first place.

Paranormal theories are the equivalent of someone theorising the existence of a (lets call it) pink hole, a region of space where all matter suddenly turns to cheese. And then tries to find evidence that backs up this theory. And doesn't find any.

There are skeptics in the scientific world as to the existence of black holes, but not that the observed data that leads us to theorise about them actually exists.
So the difference is quite distinct.

An international team of astronomers photographed the star as it zoomed around the galactic center at speeds ultimately exceeding 11 million mph (5,000 kilometers per second).
And they could demonstrate this to anyone who questioned them.

Can we say the same about evidence toward the paranormal?

[Gr8wight]

Hiya

I am wondering how many "scientific" theories would hold up to the million dollar challenge. For example, no one has been able to prove that black holes exist, worm holes, or even the "string theory." Yet, many scientists still accept them as facts.

I have yet to see a working example of a black hole, or any hard evidence that any exist. So why are there not skeptics for these theories within the scientific community?

Just a thought.

That same phenomena could be explained as being a dark-energy star (http://en.wikipedia.org/wiki/Dark-energy_star) or a magnetospheric eternally collapsing object (http://en.wikipedia.org/wiki/Magnetospheric_Eternally_Collapsing_Object). Both will work in this case.

Just because something is happening (which there is evidence that something is), does not mean that it has to be one set thing. There are other explanations, and unless one can be recreated, or directly observed, it cannot be proven.

Yes, there is something very powerful there, but that does not mean that that something powerful is a black hole.



So, you have just answered your own question. Yes there are people in the scientific community who are skeptical of black holes, and you have just mentioned two competing theories. No, the existence of black holes is not universally accepted.

I am having difficulty understanding what your point is. What, exactly are you trying to get across to us?

[snooziums]

I am having difficulty understanding what your point is. What, exactly are you trying to get across to us?

Basically, my point is that a lot of scientific "truths" cannot be proven beyond a doubt, and there is a chance that they might be proven wrong.

So, for someone to be a true skeptic, one must also realize that a lot of "truths" out there, even ones accepted and endorsed by the general scientific community, might not be as totally factual as claimed.

[quixotecoyote]

You will find few skeptics of any quality looking for that kind of truth, The very definition of skepticism is that one asks questions and seeks evidence of theories and explanations before believing in them, rather than the CT/wooish/religious method of believing a theory and then seeking evidence to support it.

Skeptics in general are not claiming to possess a 'truth' that they can use to bash other people over the head with. The only reason it might seem that way is if one takes the perspective of those who do use a specific 'truth' as the lens through which they view the world. In such an instance, seeking the most rational evidence can be viewed as an attack on them and their worldview, as 'truth's are generally much less adaptable than the evidence used to question them.

Further, the reputable portions of the scientific community do not accept 'truths'. The ideas accepted by them are based on evidence and are perfectly succeptable to change given sufficent evidence and logic indicating such a change is appropriate. You will not find this type of thinking in those groups who cage the truth in quotation marks.

[steenkh]

Basically, my point is that a lot of scientific "truths" cannot be proven beyond a doubt, and there is a chance that they might be proven wrong.
That goes without saying. Lots of scientific theories have been modified over time, and some have been discarded. Some differences between these scientific theories and the woo claims is that

The scientific theories do not contradict every other knowledge we have of the world, whereas the woo claims usually do
The scientific theories try to explain what we do not understand, whereas the woo claims usually explain what is understood perfectly well using existing theories
Woo claims are usually built on pseudo-scientific nonsense, whereas real science obviously is not
Scientific theories are examined critically by other scientists working in the same field. When did you last see a crystal healer criticise another healer for using the crystals for something that does not work?
Real science becomes better at describing the world when newer theories are developed. Woo-woos find that the older the theory, the better it fits their world

[Flange Desire]

Basically, my point is that a lot of scientific "truths" cannot be proven beyond a doubt, and there is a chance that they might be proven wrong.

So, for someone to be a true skeptic, one must also realize that a lot of "truths" out there, even ones accepted and endorsed by the general scientific community, might not be as totally factual as claimed.

[nitpick]
Your point is essentially correct but most would choose different wording - avoiding words like 'truth' and 'prove', and perhaps using words like 'evidence' and 'convincing' instead.
And in the second sentence, the use of the word 'factual' is really clouding the issue.
[/netpick]
But anyways yes, we can be deluded into believing any old stuff if it is neatly packaged up (cf religion, organic-is-better, etc, etc).

[snooziums]

Good points, steenkh, but there are some holes in even them.

The scientific theories do not contradict every other knowledge we have of the world, whereas the woo claims usually do.
Well, since there is no scientific knowledge of the afterlife, then any theory or hypothesis would not contradict anything scientific.

The scientific theories try to explain what we do not understand, whereas the woo claims usually explain what is understood perfectly well using existing theories.
But, like above, there are no scientific theories about the afterlife, its existence, or any other details about it. So while pseudo-scientific claims on the afterlife might remain unproven, they again, do not challenge any scientific belief.

Just thought those needed to be pointed out. But still good points never-the-less.

People are often attracted to pseudo-scientific claims because there is still so much that has not been scientifically proven yet, or even looked into.

[steenkh]

Well, since there is no scientific knowledge of the afterlife, then any theory or hypothesis would not contradict anything scientific.
You are quite right! We can add another point like

Real science is trying to understand concepts for which there is evidence, woo claims are usually used to understand concepts for which there is no evidence

:)

[Cuddles]

Well, since there is no scientific knowledge of the afterlife, then any theory or hypothesis would not contradict anything scientific.


But, like above, there are no scientific theories about the afterlife, its existence, or any other details about it. So while pseudo-scientific claims on the afterlife might remain unproven, they again, do not challenge any scientific belief.

Just thought those needed to be pointed out. But still good points never-the-less.

People are often attracted to pseudo-scientific claims because there is still so much that has not been scientifically proven yet, or even looked into.

Except that for there to be an afterlife there would have to be something that exists seperately from the body and exists after death. All evidence says the body is all there is and that all the matter and energy of a living body is still there in a dead body, so there can be nothing left to go to an afterlife. All science must assume that anything real can be observed. Proposing an undetectable "soul" does contradict science precisely because there is no evidence for it.

[Gr8wight]

Basically, my point is that a lot of scientific "truths" cannot be proven beyond a doubt, and there is a chance that they might be proven wrong.

So, for someone to be a true skeptic, one must also realize that a lot of "truths" out there, even ones accepted and endorsed by the general scientific community, might not be as totally factual as claimed.

Dear snooziums,

you obviously don't know a thing about science. "Truth" is an abstract concept that is swung around by the religious. There are no such things as "scientific truths." There are things that have been so deeply studied, and for which there is significant evidence, that the majority of the scientific community consider them factual, but no one considers them "truths" and everyone knows that all existing theories are subject to amendment and modification upon the discovery of new evidence.

So far, you have made no statement that the scientific world would disagree with. The fact that currently accepted theories may one day be replaced by other, different theories is a fundamental, underlying tenet of the scientific method.

So, again, I ask you: what is your point?

edited to add:


Good points, steenkh, but there are some holes in even them.


The scientific theories do not contradict every other knowledge we have of the world, whereas the woo claims usually do.
Well, since there is no scientific knowledge of the afterlife, then any theory or hypothesis would not contradict anything scientific.


The scientific theories try to explain what we do not understand, whereas the woo claims usually explain what is understood perfectly well using existing theories.
But, like above, there are no scientific theories about the afterlife, its existence, or any other details about it. So while pseudo-scientific claims on the afterlife might remain unproven, they again, do not challenge any scientific belief.

Just thought those needed to be pointed out. But still good points never-the-less.

People are often attracted to pseudo-scientific claims because there is still so much that has not been scientifically proven yet, or even looked into.

Ah, I had missed this. So, all you are trying to do is somehow justify your personal belief in an afterlife. Fine. Off you go.

[steenkh]

Ah, I had missed this. So, all you are trying to do is somehow justify your personal belief in an afterlife. Fine. Off you go.
Until corrected by snooziums, I believe that you are misreading him/her. I found snooziums' post to be a philosophical digging into whether we are setting other standards for woo claims than real science. I have not noticed snooziums actually supporting wooism in this thread, but rather trying to figure out what it is that attracts people to it. And snooziums actually supported my criticism of wooism, so I think you have been somewhat hasty here.

[Gr8wight]

Until corrected by snooziums, I believe that you are misreading him/her. I found snooziums' post to be a philosophical digging into whether we are setting other standards for woo claims than real science. I have not noticed snooziums actually supporting wooism in this thread, but rather trying to figure out what it is that attracts people to it. And snooziums actually supported my criticism of wooism, so I think you have been somewhat hasty here.

Possible. However, it is a very common occurence at these forums that a new poster sounds emminently reasonable, and reasoning at first, and slowly devolves into deeper and deeper wooism. I'm not saying that this is the case here, but the warning signs are there.

I will wait and see what snooziums says about it.

[drkitten]

Until corrected by snooziums, I believe that you are misreading him/her. I found snooziums' post to be a philosophical digging into whether we are setting other standards for woo claims than real science.

I suspect a combination of both.

Not that there's anything wrong with that.

However, I think that snooziums may be confused about the state of scientific evidence regarding the afterlife. He claims that "there is no scientific knowledge of the afterlife, then any theory or hypothesis would not contradict anything scientific." He further claims that "there are no scientific theories about the afterlife, its existence, or any other details about it." This is also untrue.

There is a substantial body of psychological theory and evidence that suggests the afterlife does not exist. In brief, we have well-substantiated and explanatory theories about human behavior that do not incorporate a "soul" or any similar object. We even have well-substantiated and explanatory theories that explain why people may believe incorrectly in the afterlife.

This isn't "knowledge" (in the sense of "proof"), but it's certainly evidence. Most biologists would consider the complete absence of evidence for amphibians on the Galapagos islands (prior to 1998 or so), together with the well-established theories about what should and shouldn't be there (including amphibians) to be ample reason to believe that there simply aren't any. In this sense, disbelief in the afterlife is as scientific as disbelief in native Galapagan frogs.

The maxim "absence of evidence is not evidence of absence" is one of the most misunderstood. Of course absence of evidence can be evidence of absence. The absence of footprints in fresh snow is generally regarded as proof that no one's walked over that field since the snowfall. The key is the theoretical framework that makes interpretation of the absence possible. Something we'e got, in the case of the afterlife. Of course, new evidence might come up to cause us to change our theories -- but I'm not holding my breath.

[Crossbow]

Hiya

I am wondering how many "scientific" theories would hold up to the million dollar challenge. For example, no one has been able to prove that black holes exist, worm holes, or even the "string theory." Yet, many scientists still accept them as facts.

I have yet to see a working example of a black hole, or any hard evidence that any exist. So why are there not skeptics for these theories within the scientific community?

Just a thought.


If I recall, Randi did essentially admit that it would be possible for a person to have a scientifically based tool or technique that is so new and so different from anything else we have every encountered, that it would appear to be a paranormal phenomena to the uninitiated; and they may thus win the JREF prize money.

However, I would expect that such a tool or technique would be the result of considerable scientific study and research where funding and information release is at least fairly well controlled. Therefore, I would have to say that it is quite unlikely that such a thing would be presented to JREF before other scientists.

Also, if someone did develop such an item via the scientific process, then I would expect that the person who made the discovery would be more motivated to show his peers the item since doing so may help him to get a prestigious academic appointment and/or additional research funding and/or Nobel Prize.

[snooziums]

All evidence says the body is all there is and that all the matter and energy of a living body is still there in a dead body...

I know that all evidence points to all matter being there, but I have not heard of anything about there being all of the energy there. Kind of like pulling the plug on a radio, all matter is there, but the energy is not (bad analogy, but I will look more in into it later). If all the energy was still there, it would seem that there would still be muscle spasms long after the actual death happened, with that energy having nowhere to go.

Proposing an undetectable "soul" does contradict science precisely because there is no evidence for it.

Ah, but what about the undetectable mind? It is known that the mind works off the brain, yet how it works (or even where in the brain it is), is still not clearly known (if it was, there would be brain surgery to fix any and all mental conditions).

"Truth" is an abstract concept that is swung around by the religious. There are no such things as "scientific truths."...

OKay, I see. Sadly, though, a lot of textbooks still throw abound the "truth" idea, and a lot of instructors still use the term "scientific truth."

...we have well-substantiated and explanatory theories about human behavior that do not incorporate a "soul" or any similar object...

Although Jungian Psychology (which is still considered "mainstream") still expresses the idea of the soul, as well as a "collective conscious" and "archetypes" (which are models unconsciously shared in different places). Many psychology classes at college still follow Jung's models of the human mind.

I am not saying that any of the above is true or false, however it seems that, in psychology at least, which is the main study of the mind, that such ideas of the soul and a connected unconscious still exist and are, on some level, accepted.

One think about being a skeptic is that I find myself questing everything, even current accepted scientific theories. It makes life complex, although a bit fun.

[steenkh]

I know that all evidence points to all matter being there, but I have not heard of anything about there being all of the energy there. Kind of like pulling the plug on a radio, all matter is there, but the energy is not (bad analogy, but I will look more in into it later). If all the energy was still there, it would seem that there would still be muscle spasms long after the actual death happened, with that energy having nowhere to go.
Actually, the analogy is OK, but it shows the opposite of what you think! All the energy in the radio is still present when you pull the plug, but no more energy is flowing into it. In the dead body, all the energy is also present, but no more energy is put into the system by breathing and eating. It is not a question of the amount of energy, but of how the energy is used, and in a dead body, the energy is only used for decomposition, because the mechanisms that would have caused the body to be alive, have broken down. Actually, as you probably know, nails and hair will continue to grow for a while, which shows that not all mechanisms have broken completely down yet.

Ah, but what about the undetectable mind? It is known that the mind works off the brain, yet how it works (or even where in the brain it is), is still not clearly known (if it was, there would be brain surgery to fix any and all mental conditions).

The mind is not so undetectable. Brain scannings clearly show when the mind is active, and which improved knowledge and instrumentation, it has also become possible to tell in general terms what the mind is doing. For instance, it can easily be seen on scannings if the mind is sleeping.

Although Jungian Psychology (which is still considered "mainstream") still expresses the idea of the soul, as well as a "collective conscious" and "archetypes" (which are models unconsciously shared in different places). Many psychology classes at college still follow Jung's models of the human mind.

Jungian psychology may be considered mainstream by some, but it is based on concepts for which there is no evidence. In fact, you can argue that not all of psychology is science at all.

One think about being a skeptic is that I find myself questing everything, even current accepted scientific theories. It makes life complex, although a bit fun.
You are welcome to question established theories. Indeed, real scientists do it all the time.

[SirPhilip]

In short, no one and no instrument has directly seen a blank hole. SO the chances of a black hole being real are must about par with things like auras and telepathic communication. Sure many arguments can be made, and some indirect evidence (mathematics does NOT count as evidence), but still no hard proof. A black hole is simply an object with enough mass to completely bend light around it. It does however, radiate energy (called Hawking radiation) due to the second law of thermodynamics. If not, what's this (http://www.radix.net/%7Erypfri/blackh1.gif) then?

[snooziums]

A black hole is simply an object with enough mass to completely bend light around it. It does however, radiate energy (called Hawking radiation) due to the second law of thermodynamics. If not, what's this (http://www.radix.net/%7Erypfri/blackh1.gif) then?

Actually, a black hole is something that escape to the outside universe is impossible. The boundary of this region is a surface called the event horizon. This surface is not physical, just an imaginary boundary. Nothing can move from inside the event horizon to the outside, even briefly. So, it does not bend light, it actually destroys it.

Yet, there are other theories about "objects" that can bend light, as shown above. So while black holes may exist, there is a small chance that they do not.

[SirPhilip]

Actually, a black hole is something that escape to the outside universe is impossible. The boundary of this region is a surface called the event horizon. This surface is not physical, just an imaginary boundary. Nothing can move from inside the event horizon to the outside, even briefly. So, it does not bend light, it actually destroys it. Yet, there are other theories about "objects" that can bend light, as shown above. So while black holes may exist, there is a small chance that they do not. I'll assume this is a troll, since you were pointed to google the definition of a black hole by more than one user here. Apparently you didn't.

[snooziums]

I'll assume this is a troll, since you were pointed to google the definition of a black hole by more than one user here. Apparently you didn't.

Actually, that information comes from the wiki page on black holes.

Maybe wiki is wrong on this one? But that is where that information comes from.

[Piggy]

Actually, a black hole is something that escape to the outside universe is impossible. The boundary of this region is a surface called the event horizon. This surface is not physical, just an imaginary boundary. Nothing can move from inside the event horizon to the outside, even briefly. So, it does not bend light, it actually destroys it.
Ok, obviously you need to read up a little more on black holes before you go opining on them.

First, Hawking radiation is a bona fide theory. SirPhillip is not wrong about this. According to Sir Stephen, particle-antiparticle pairs generated on the event horizon will either fall into the black hole, move away from the black hole, or split with one falling in and one falling out. The net result of this process must be radiation emerging from the black hole. (Think about it.)

Also, the event horizon is not imaginary, but is most definitely physical.

Finally, all high-gravity objects bend light.

[snooziums]

Ok, obviously you need to read up a little more on black holes before you go opining on them. ... Also, the event horizon is not imaginary, but is most definitely physical.

Direct from the wiki article on black holes:

A black hole is an object predicted by general relativity with a gravitational field so strong that nothing can escape it — not even light.
A black hole is defined to be a region of space-time where escape to the outside universe is impossible. The boundary of this region is a surface called the event horizon. This surface is not physical, just an imaginary boundary. Nothing can move from inside the event horizon to the outside, even briefly.

Like I said, my source was from the wiki article. I did not make that up. So, like I said, maybe the wiki article is wrong...?

[Piggy]

Like I said, my source was from the wiki article. I did not make that up. So, like I said, maybe the wiki article is wrong...?
Like I said, you need to read up a little more. Wikipedia is a bulletin board, not a science journal.

[snooziums]

Like I said, you need to read up a little more. Wikipedia is a bulletin board, not a science journal.

However, even the science journals cannot agree to what exactly a black hole is.

Below are several opinions from a scientific journal:

Hawking cracks black hole paradox:

After nearly 30 years of arguing that a black hole destroys everything that falls into it, Stephen Hawking is saying he was wrong. It seems that black holes may after all allow information within them to escape. Hawking will present his latest finding at a conference in Ireland next week.

The about-turn might cost Hawking, a physicist at the University of Cambridge, an encyclopaedia because of a bet he made in 1997. More importantly, it might solve one of the long-standing puzzles in modern physics, known as the black hole information paradox. ...


The black hole survival guide
06 September 2003
Marcus Chown
Magazine issue 2411
Falling into a black hole need not spell certain doom. Marcus Chown looks forward to the ultimate thrill ride
COULD you fall into a black hole and avoid being crushed by its intense gravity? Because the laws of physics break down under these conditions, it has widely been considered impossible even to imagine what would happen deep inside these fearsome objects. But Igor Novikov thought it was worth trying anyway. And by probing exactly how the laws of physics break down, he has challenged the conventional view that a trip to a black hole spells certain death.

Of course, Novikov, who heads the Theoretical Astrophysics Center in Copenhagen, Denmark, is not planning to visit a black hole. But physicists still consider the problem worth thinking about; these calculations can give us insight into what happens where the fabric of space-time becomes so tremendously warped that it shatters into droplets or quanta. "Here the general theory of relativity, Einstein's theory of gravity, is no longer valid," says Eric Poisson of ...


Life inside a black hole: 10 February 2006 Paul Wesson Magazine issue 2538
We all know that falling into a black hole is about as unpleasant as things get, but find a five-dimensional one and things look a lot more comfy - in fact, it's a lot like home
WE ALL know what happens if you fall into a black hole. It's not pretty - you get ripped limb from limb before vanishing down the plughole.

However, there is a way for you to live inside a black hole: find one that has five dimensions. Life inside a 5D black hole is known to be rather more sustainable than it is in the 4D version. In the 4D case, you would experience "tidal" forces that vary so vastly over short distances that your body would be pulled apart. But in the 5D case, there is no physical plughole, and the tidal forces are negligible, so you could happily explore without fear of dismemberment. And, according to the results of my research, you may be doing that right now. A mathematical analysis says that our universe may well be a 5D black hole (General Relativity and Gravitation), vol 37, p ...

With that much varying opinion among scientists that believe in black holes, how could it ever pass the challenge?

Which, if black holes could pass the challenge, was my original question.

[Loss Leader]

Sure many arguments can be made, and some indirect evidence (mathematics does NOT count as evidence), but still no hard proof.

The fact that you don't understand the proof, doesn't mean the proof doesn't exist.

Scientists created theories of how black holes would affect the space around them. They looked up and saw exactly the effects they predicted. When you see stars reacting to a massive gravity well but you can't actually find the gravity well in your telescope, that's a black hole.

Now, can you predict exactly what John Edwards will be able to tell me about my dead grandfather, write it down and then see how close John Edwards gets? I doubt it.

[GregC]

But can it be proven 100 percent that that something is a black hole? No, not 100 percent. So while the black hole theory is most likely, that does not mean that it is absolute truth.

Actually snooz, the JREF challenge is less stringent than you are being right now. If I have read the rules correctly JREF and the applicant agree on a test procedure and then agree on a success rate. I believe I've read where 50% success would have been enough to win the JREF challenge. JREF does not require that anyone prove their claim 100%. Those more up on the challenge rules please correct me if I am wrong.

[Piggy]

However, even the science journals cannot agree to what exactly a black hole is.
You are conflating 2 very different situations.

Although Hawking admits being wrong about certain assumptions derived from incomplete information/analysis, the development of his theory regarding radiation escaping from black holes did not disturb the core theory.

Compare this to the history of geocentric theory. As evidence supporting heliocentrism accumulated, the fundamentals of the model had to be continually changed and complexified until finally the entire model became hopelessly self-contradictory.

And compare geocentrism to Darwinian evolution, which was both confirmed and refined by genetics and embryology. These discoveries answered debates in ways that favored Darwinian theory and disproved competing theories, and in doing so changed our understanding of how the process operates.

So we should not take debate surrounding a theory, in and of itself, as evidence that there is no agreement on the subject at all.

There is no argument over what a black hole fundamentally is. In fact, these discussions of the details depend upon there being a "hard" central theory.

Look at it this way. We could consider the search for black holes to be a scientific "challenge". The application has been accepted. Why? Because verifiable models of the universe allow for, even predict, these odd creatures called black holes. They're not something that simply appeared to someone in a vision of were handed down in ancient tales.

Just because some objects that had been proposed as actual black holes may not, in fact, be black holes (http://www.world-science.net/othernews/060811_quasar.htm)... this is not evidence against their existence. The search goes on, as it should. If I'm looking for my car in a parking lot, approach a teal Corolla, then notice a GOP bumper sticker on the back, I conclude "Oops, not my car", not "I guess I don't really have a car".

Now, take God theory, as a contrary example. God theory really does have no central qualities at all. Pagan pantheism, Jesus worship, Zen aconceptualism, deism, Krishna consciousness, ineffable mystic experience, animism, they all get a seat at the table.

Now there's a case where it's really true that adherents of a theory cannot agree on what in the world it is.

[SirPhilip]

You are conflating 2 very different situations. Now there's a case where it's really true that adherents of a theory cannot agree on what in the world it is. The basic mechanics of black holes are sensical and simplistic. When a star, three times massive than ours or larger, implodes, it's mass becomes compressed into a volume which is smaller than a Schwarzschild radius. This ratio of mass to volume creates a singularity, which is an object with an escape velocity greater than light. Light, for example, travels at a limited speed. Gravity, however, has no limitation. This is where advanced mathematics, imaginary numbers, and Cheshire cats come in, because you are dealing with relativistic conditions where mass exists in a state in which it cannot move, except through an exotic, theoretical process of entropy. What actual point are you trying to make?

[snooziums]

The basic mechanics of black holes ... What actual point are you trying to make?

It is like evolution. When Darwin proposed it, there was no proof (that was sen then) to prove that it existed. He saw the connection between primates and humans, and made a very educated theory that there was a connection. It was ONLY after fossils were found that the proof of evolution was there.

It is like stating that this is point A, and this is point Z, thus, the steps between must be in this order (make up some order). Like coming upon a highway with lots of exhaust fumes and saying "there are a lot of exhaust fumes, thus a large truck must have passed by." Well, there might have been several smaller vehicles that created those exhaust fumes.

Back to the subject: We see the end result of something powerful. We see that something bends light and emits a lot of X-rays. However, do we know what happens in the middle of that? No, thus far, there have been many thoughts, but still, what happens in the middle of all of that is still not proven (see above where professional scientists think that some things might be able to escape a black hole.

So, one of two things happens. One, it might not be a "black hole" like once thought, or two, the definition of a black hole is changed.

So, if someone proves that there are black holes and that NOTHING can escape them, why do we have these scientists saying that some kinds of energy can? Thus far, the term "black hole" is still very vague, and any more absolute version of the workings of black holes cannot be proven.

[nathan]

Also, the event horizon is not imaginary, but is most definitely physical.
Part of the layman's confusion about this might be because an observer falling into a black hole notices no changes when passing the event horizon (i.e. they cannot tell that they have passed the event horizon). Observers outside the event horizon do notice.

Anyway, any macroscopic object will be ripped appart by tidal forces before that point, AIUI.

[steenkh]

Actually snooz, the JREF challenge is less stringent than you are being right now. If I have read the rules correctly JREF and the applicant agree on a test procedure and then agree on a success rate. I believe I've read where 50% success would have been enough to win the JREF challenge. JREF does not require that anyone prove their claim 100%. Those more up on the challenge rules please correct me if I am wrong.
In the cases where the JREF has lowered the odds is when even a lower success would be paranormal. So if your claim is that you can do something with 80% success, but even 50% would be paranormal (but still only 1 in 1,000,000 that it is done by chance), the JREF has sometimes suggested lowering the odds, especially when this makes the testing easier.

[SirPhilip]

It is like stating that this is point A, and this is point Z, thus, the steps between must be in this order (make up some order). Like coming upon a highway with lots of exhaust fumes and saying "there are a lot of exhaust fumes, thus a large truck must have passed by." Well, there might have been several smaller vehicles that created those exhaust fumes. Looks like you're just going to have to take my word for it something that can engulf a star probably has something to do with lots of mass.

Back to the subject: We see the end result of something powerful. We see that something bends light and emits a lot of X-rays. However, do we know what happens in the middle of that? No, thus far, there have been many thoughts, but still, what happens in the middle of all of that is still not proven (see above where professional scientists think that some things might be able to escape a black hole. So, one of two things happens. One, it might not be a "black hole" like once thought, or two, the definition of a black hole is changed. It could be a big 8 ball, or a giant licorice candy, or a big lump of coal, instead of a highly compressed mass that emits radiation in the form of antimatter particles.

So, if someone proves that there are black holes and that NOTHING can escape them, why do we have these scientists saying that some kinds of energy can? Thus far, the term "black hole" is still very vague, and any more absolute version of the workings of black holes cannot be proven.There is nothing particularly mysterious about black holes. Wormholes on the other hand, are a different story, and much more in line with what you are talking about.

[steenkh]

So, if someone proves that there are black holes and that NOTHING can escape them, why do we have these scientists saying that some kinds of energy can? Thus far, the term "black hole" is still very vague, and any more absolute version of the workings of black holes cannot be proven.
The definition of a black hole is not vague, but your understanding is limited. As several have pointed out, Hawking radiation is not controversary, and it is fully within the definition of a black hole. Hawking radiation is by the way, as as I understand, not radiated from the black hole as such but from the event horizon, which is imaginary only in the sense that there is no physical boundary, but physical in the sense that it is observable, and it interacts with the surrounding world, as in the radiation it makes.

The existence of black holes can be proven. When we observe stars and other matter circling something, we can calculate the mass of this something if we can calculate the mass and speed of the matter circling it. If the mass is above a certain limit, we have a black hole per definition.

[Cuddles]

I know that all evidence points to all matter being there, but I have not heard of anything about there being all of the energy there. Kind of like pulling the plug on a radio, all matter is there, but the energy is not (bad analogy, but I will look more in into it later). If all the energy was still there, it would seem that there would still be muscle spasms long after the actual death happened, with that energy having nowhere to go.

Very bad analogy. Humans do not have an external power supply. Take a battery powered radio and hit it with a stick until it stops working. Is the energy still in the batteries? Yes. The potential energy stored in it can no longer be used so the radio is dead, but all the matter and energy is still there.

Ah, but what about the undetectable mind? It is known that the mind works off the brain, yet how it works (or even where in the brain it is), is still not clearly known (if it was, there would be brain surgery to fix any and all mental conditions).

As already pointed out, we can detect the mind. And again, all evidence points to it being only brain function and nothing mystical at all.

It is like evolution. When Darwin proposed it, there was no proof (that was sen then) to prove that it existed. He saw the connection between primates and humans, and made a very educated theory that there was a connection. It was ONLY after fossils were found that the proof of evolution was there.

There's another subject for your reading list. Of course there was proof of evolution, that's exactly why he came up with the theory. He wasn't even the first, he just had a more complete theory and published more about it. I recomend "The Science of Discworld 3" by Terry Pratchett, Ian Stewart and Jack Cohen as a very good laypersons guide to evolution and the history of Darwin himself.

It is like stating that this is point A, and this is point Z, thus, the steps between must be in this order (make up some order). Like coming upon a highway with lots of exhaust fumes and saying "there are a lot of exhaust fumes, thus a large truck must have passed by." Well, there might have been several smaller vehicles that created those exhaust fumes.

And at first guess that would probably be a good assumption. If you wanted to distinguish between the two theories you would predict what would be seen in the case of a lorry or lots of cars and compare the predictions with the observations. I'm not sure exactly what your point was, but I'm pretty sure you didn't make it.

Back to the subject: We see the end result of something powerful. We see that something bends light and emits a lot of X-rays. However, do we know what happens in the middle of that? No, thus far, there have been many thoughts, but still, what happens in the middle of all of that is still not proven (see above where professional scientists think that some things might be able to escape a black hole.

We see almost exactly what black hole theory predicts. No other theory predicts the same, so black holes are by far the most likely explanation, although it will never be proved, in the same way that evololution and gravity will never be proved. In addition there are numerous side effects. No supernova remnants are observed above a certain size, so if black holes don't exist, where are they? Most rivals aren't produced by the same process.

So, one of two things happens. One, it might not be a "black hole" like once thought, or two, the definition of a black hole is changed.

Or the theory stays basically the same with a few minor adjustments, just like any other well-established theory.

So, if someone proves that there are black holes and that NOTHING can escape them, why do we have these scientists saying that some kinds of energy can?

Hawking radiation is not escaping the black hole. It is produced by pair-prodution at just outside the event horizon, where one particle is captured and the other escapes. This effectively causes the hole to acquire negative mass, so it becomes lighter and eventually evaporates, but at no point does anything cross the event horizon from inside to outside. It is an interesting phenomenon, but says nothing about the actual nature of a black hole, only what happens just outside the hole.

Of your other two theories posted, one refers to extra dimensions, in which case of course our theories will be different. The other does not mention anything leaving a black hole, it only says that you could survive inside one.

Thus far, the term "black hole" is still very vague, and any more absolute version of the workings of black holes cannot be proven.

It is an object that has an escape velocity larger than the speed of light in a vacuum. Doesn't sound all that vague to me. Anything more than that is just free bonus.

[Nucular]

Hi snooziums,

People theorise in order to explain specific phenomena which are otherwise unaccounted for, or poorly accounted for, by existing theory. They then test the theory by making predictions of what else we might see if the proposed theory is true (hypotheses), and then seeing if those things are indeed present. Theories, as many have already pointed out, are always provisional in science, and are thus able to be revised or thrown out at any point if the evidence contradicts them.

In the case of black holes, as you understand, they were hypothesised based on the theory of general relativity. This meant people went looking for them, since to find evidence of them would be to find evidence for the theory which predicted them; and to fail to find evidence of them would imply that the general theory of relativity was incorrect (or that someone had done his sums wrong).

In order to 'test the hypothesis' of black holes, people decided to figure out what a black hole might be like if it existed, and therefore how best we might find one. Since black holes, if they exist, are black, and so is space, it seemed unlikely that they'd see one directly in a telescope; additionally, it was impractical to set out on a voyage to find a black hole and take a photograph. Thus, predictions were made about what other properties black holes might have, other than blackness, and to look for signs of those instead - the 'indirect' evidence you've mentioned.

Such evidence has indeed been found, as you've noted; and, although some perfectly legitimately argue that there could be other phenomena which could explain the observations as well, these then become theories to be hypothesised about and tested in their own right. Meanwhile, Occam's razor would suggest that, given the present state of the data, on balance, black holes are quite likely to exist.

I've rambled about this just to clarify the process. The whole process is one of scepticism, coming from the scientific angle of attempting to disprove existing theory ('prove the null hypothesis') in order to 'crash test' it.

The context the other thread you're participating in (http://forums.randi.org/showthread.php?p=1930152#post1930152) gives your discussion here suggests that you might consider an 'afterlife' theory (reincarnation?) to be just as viable an idea as black holes, hence the discussion here. I was wondering if you still consider this to be the case, given the information all the posters on this thread have provided, and if so, what the equivalent process might be to support the theory?

Apologies if I've misunderstood your intention; but if I have, I'm afraid I've missed the real point.

Also, New Scientist isn't a 'science journal', it's a popular science and technology magazine, not a peer-reviewed publication.

[geoman]

Below are several opinions from a scientific journal:



New Scientist is NOT a 'scientific journal'!

edit: Dang you, Nucular!

[Cuddles]

New Scientist is NOT a 'scientific journal'!

edit: Dang you, Nucular!

I was going to say that as well, but these seem to be fairly good articles on some less-than-mainstream hypotheses (plural of hypothesis?). From what he quoted it appears that he has only read the taster and not actually registered to read the whole article, so his entire argument is made without having any idea of what they are actually saying. Needless to say, none of it actually contradicts black hole theory as he claims.

[Piggy]

So, if someone proves that there are black holes and that NOTHING can escape them, why do we have these scientists saying that some kinds of energy can?
It is crucial that we distinguish between the necessary core of a theory, and assumptions/conclusions derived from the core theory.

As others have pointed out, black holes were the necessary consequence of certain models of mass, energy, and gravitation -- models which have proven themselves highly accurate.

So, why should there be black holes? Simple. Because, if we run the math to describe what must happen when very massive stars (about 4 times as massive as our sun) "burn out" -- that is, they use up the available fuel which was being turned into energy, which in turn was "pushing outward" against the force of gravity -- we discover that as they collapse, the force of gravity is so strong (remember, more mass, more gravity, which is why astronauts can hop so high on the moon) that the forces pushing the atoms away from each other are overwhelmed. In short, gravity wins.

The result is what is called a singularity, a region where much of our ability to describe what's going on simply breaks down. But we do know some things. For example, Einstein's models showed that gravity affects not just massy objects like astronauts, but also affects light. He predicted, for instance, that light from the stars would be "bent" around massive objects like planets, so that (from our point of view) a star whose light must pass near large celestial bodies in order to reach us would appear slightly off from its actual position. Turns out, he was right -- not just generally, but his numbers work, too.

So using his numbers, we can calculate the escape velocity for the body which results from the collapse of a 4+ solar mass star.

Escape velocity is the speed necessary to provide enough "push" to overcome the "pull" of gravity. A pop fly ball falls back to the field because gravity is stronger than the energy provided by the bat. A vehicle designed to reach the moon, however, has enough energy from its rockets to overcome the earth's gravity, and so it leaves the atmosphere.

For the collapsed star which has formed a singularity, the escape velocity is greater than the speed of light. Therefore, no light from inside the object can escape.

There has been no overturning of this part of the theory (or of anything I've mentioned thus far). In fact, there's no controversy about it. When black holes were shown to be the inevitable result of Einstein's models, it was disturbing to some, but the models have been verified to a high degree of accuracy.

In the 1970's, Steven Hawking got to thinking about black holes, and realized something astonishing. Quantum fluctuations right on the event horizon would result in a certain number of particle/antiparticle pairs going their separate ways, so that energy is carried away from the black hole, and it slowly "evaporates".

This, however, does not change the fact that light cannot escape from inside a black hole. The evaporation arises from quantum level vacuum fluctuations at the event horizon. Normally, these anti/particle pairs are ephemeral -- they pop up "from nowhere", then recombine and essentially "vanish" in doing so. That maintains the conservation of energy in the universe. A black hole's event horizon can play screwy with them, however, splitting them up so they don't recombine -- one goes into the black hole where it cannot escape, while one moves out into the universe where it survives.

So you see, not only does the theory of radiation from black holes not contradict the proposition that no light can escape from them, it actually depends on this being true! Quite amazing stuff.

I hope that explains the situation. If not, feel free to ask more about it. I'm sure many people on this board will be happy to help you learn.

[snooziums]

Very bad analogy. Humans do not have an external power supply. Take a battery powered radio and hit it with a stick until it stops working. Is the energy still in the batteries? Yes. The potential energy stored in it can no longer be used so the radio is dead, but all the matter and energy is still there.

However, the radio can be fixed and used again. But can humans be fixed after death (even if decay has not set in yet)? If the energy is still in the body, and decay has not been started (which takes about 72 hours to begin), then why cannot humans be restored as well?

As already pointed out, we can detect the mind. And again, all evidence points to it being only brain function and nothing mystical at all.

So we can tell what someone is thinking and what emotions they are feeling just by scanning the brain? Show me a study that reveals this.

There's another subject for your reading list. Of course there was proof of evolution, that's exactly why he came up with the theory.

I was referring to fossils, that concreted the proof of the theory of evolution. Did Darwin see fossils that showed the connection between humans and primates, no. He came up with his theory, and later, fossils were found that became the hard proof for his theory.

The definition of a black hole, as I have always been told, is something so dense that nothing, not even light can escape it. However, there is thought among scientists in the field that some things can escape (see above reference that knowledge might be able to escape). Well, if something can except, then how does that fit into the standard description that nothing can escape? (The nothing can escape is from the school textbooks that I have read - so maybe their definition is out of date?).

For the collapsed star which has formed a singularity, the escape velocity is greater than the speed of light. Therefore, no light from inside the object can escape.

Then, why are some scientists on the subject saying that "knowledge" can escape?

Also, New Scientist isn't a 'science journal', it's a popular science and technology magazine, not a peer-reviewed publication.New Scientist is NOT a 'scientific journal'!

Okay. Can anyone recommend a good scientist journal that can be read online? Please do not say "library" since my local public library does not have that kind of stuff, and to use any college library, you need a student ID.

... suggests that you might consider an 'afterlife' theory (reincarnation?) to be just as viable an idea as black holes, hence the discussion here. I was wondering if you still consider this to be the case, given the information all the posters on this thread have provided, and if so, what the equivalent process might be to support the theory?

Oh yes, that. I never said that I could prove that belief (mine). And like I am saying here, it is not that I do not believe in black holes, it is just I do not see how they can be proven as what they claim to be where absolutely nothing escapes. So it is not that I do not believe in black holes, just I am not seeing that proof of "nothing escapes."

[Thinktoomuch]

Hello everybody. This is my first post ever, please be gentle. It appears to me that the focus of this thread has moved from "would cutting edge scientific theory pass the challenge" to "what is scientific theory anyway?"

Be as it may, I would like to add a new log onto the fire.

So that you do not have to guess where I come from, I define myself as a rational thinker (I find skeptic too limiting a word) currently interested in finding whether the chi theories passed on to me by my martial arts masters can stand up to scrutiny. I am at the "favourably impressed" stage, I hope this does not authomatically make a woo of me in your eyes.

Having came across references to the work of Dr Leonard Wisneski (Professor of medicine at George Washington University and a fellow of the American College of Physicians) on the human energy field, I would appreciate comments from anybody familiar with his work and opinions whether it can be put in the "cutting edge scientific theory" basket or not.
Does anybody take him seriously (his qualifications are impressive enough) or not? If not why?

The mixture of scholarship and amateurishness of a place like this can't be helped, but could you pleeeease be thorough in quoting your sources? (relying on wikipedia, how embarrassing!)
Thanks in advance.

[steenkh]

However, the radio can be fixed and used again. But can humans be fixed after death (even if decay has not set in yet)? If the energy is still in the body, and decay has not been started (which takes about 72 hours to begin), then why cannot humans be restored as well?
Humans are a tiny bit more complicated than radios. We can actually sometimes resurrect humans from conditions close to death, but actual death where the brain has stopped too is currently out of reach. But there is no reason why it should not be possible in the future. Contrary to radios, humans have built-in self-destruct mechanisms collectively called aging, and if you really want to resurrect old people who are dead, you would not only have to fix problems like damaged heart etc, but also enter every single cell in the body and defuse or prolong the aging mechanisms. And you would have to know exactly what you are doing, because the aging mechanisms can also be crucial for some functions to work.

So we can tell what someone is thinking and what emotions they are feeling just by scanning the brain? Show me a study that reveals this.

I will let somebody else google the for you. Obviously, this is still at the early stage, but there are lots of things that can be revealed through brain-scanning, and as the technique improves there will become more details, even if all details will probably not become avalable because of differences in individual humans that might become impractical to overcome, and because of the huge computing power that would be needed. But that is not important. The important point is that even though humans can never get the ability to read the mind of other humans through brain-scanning, it can be shown that the brain is working on the same principles as everything else in the world, which means that it is deterministic, and not mysterious at all, only hugely complicated.

I was referring to fossils, that concreted the proof of the theory of evolution. Did Darwin see fossils that showed the connection between humans and primates, no. He came up with his theory, and later, fossils were found that became the hard proof for his theory.

I have no idea of if Darwin had access to the right fossils or not, but he certainly had access to modern skeletons, and from those alone it would be a safe proposition to link humans and primates.

The definition of a black hole, as I have always been told, is something so dense that nothing, not even light can escape it. However, there is thought among scientists in the field that some things can escape (see above reference that knowledge might be able to escape). Well, if something can except, then how does that fit into the standard description that nothing can escape? (The nothing can escape is from the school textbooks that I have read - so maybe their definition is out of date?).

Your textbooks might easily be out of date, but more probably, they are just too popularized. As it has already been pointed out to you, Hawking radiation is not emitted from the black hole as such, but from outside the black hole's event horizon. And the presence of Hawking radiation obviously contains information, about the black hole, for instance its size (Hawking radiation varies with size). You can conclude that information about the black hole can be gleaned from its interaction with the physical world outside the event horizon.

[nathan]

I was referring to fossils, that concreted the proof of the theory of evolution. Did Darwin see fossils that showed the connection between humans and primates, no. He came up with his theory, and later, fossils were found that became the hard proof for his theory.
I don't know whether Darwin had access to fossil humanoids or not. But you'll notice you've stated a falsifyable prediction that Darwin's theory makes -- namely that such fossils exist. Such fossils have been found, thus adding evidence to Darwin's theory. If no such fossils had been found, Darwin's theory would have been in trouble.

[Piggy]

Speaking of information escaping from a black hole....

snooziums does not appear genuinely interested in learning anything about the scientific theories s/he purports to discuss. The point of this thread, rather, seem to be to make uninformed, naive quibbles -- Duane Gish style -- at science with the aim of portraying it as some sort of game of pin the tail on the donkey.

If the OP were actually interested in the topic, s/he would carefully consider the responses that others are posting, rather than continuing to bring out one uninformed snipe after another.

But of course, science is not just a game of wild guesses. Scientific theories, to get any play at all, must be consistent with what is verified and with observation. Even radical discoveries which challenge widespread assumptions are given their hearing if they meet these criteria. Yet even so, all new ideas must be tested, and their predicted results verified.

Consider the discovery that the rate of universal expansion is accelerating. This ran totally contrary to the ubiquitous assumption that expansion would be slowing down due to the pull of gravity. Yet known fact did not *require* that the expansion rate be slowing... we know that our data regarding the composition of the universe is incomplete... and the observations were replicated when put to the test.

However, this advancement in our understanding did not reverse well established models of relativity, gravitation, etc. It was accommodated by concluding that there were likely other forms of matter/energy which our instruments were not yet able to detect -- it certainly wouldn't be the first such discovery.

Consider also the case of Planck's "discovery" of quanta. At first, Planck's proposal was "a purely formal assumption and I really did not give it much thought" (letter from MP, 1931, regarding his work in 1900). In other words, originally, he considered it a mere mathematical abstraction. And yet:

Over the next three years Planck became convinced that quantum theory marked the beginning of a new chapter in the history of physics and, in this sense, was of a revolutionary nature. "The hypothesis of quanta will never vanish from the world," he proudly declared in a lecture of 1911. "I do not believe I am going too far if I express the opinion that with this hypothesis the foundation is laid for the construction of a theory which is someday destined to permeate the swift and delicate events of the molecular world with a new light."
Source: http://physicsweb.org/articles/world/13/12/8

In this case, a model which was at first considered a mere convenience turned out to be highly significant.

And of course, the reason that these things can happen is that science tests itself. Science, even at its most radical, is extremely conservative. New ideas have to prove themselves.

As a result, there are always controversies going on. Yet this doesn't mean that any-and-everything is up for grabs, or that nothing is known. As I've said before, we will never go back to geocentrism, for example, or a flat earth, or cosmic ether, or phlogiston, or spontaneous generation.

The proof of the efficacy of science is all around us. We would not be posting messages on a Web board via our computers if atomic theory and relativity and quantum mechanics were dead wrong. And it is this modern model of the universe -- the one that's been verified to an amazing degree of accuracy and allowed us to explore the vastness of space and the secrets of the atom -- which tells us that black holes should exist.

But the state of the art is now so advanced, and the scales being explored are so disproportional to the scale of daily human activity and thought, that it is no longer possible -- like the ancient Greek philosophers -- to merely apply fundamental reason and common sense to an issue and discuss it meaningfully.

To understand even the fundamentals of modern scientific models and discoveries, we must dig. It takes some doing. And if we ignore the undeniable fact that established science has been verified not just by thought but by works, if we trot out naive barbs at every turn to attempt to shoot it down before we even comprehend it, then no understanding is possible.

[Piggy]

I was referring to fossils, that concreted the proof of the theory of evolution. Did Darwin see fossils that showed the connection between humans and primates, no. He came up with his theory, and later, fossils were found that became the hard proof for his theory.
The fossil record is actually not the best evidence for Darwinian evolution. The hard proof came more from research in genetics and embryology.

Also, it was not merely a question of proposing a "connection between humans and primates". The issue at hand was speciation itself. Evolution had fairly wide acceptance in Darwin's day. It was the mechanism of evolution that proved elusive.

Lamarck, for example, proposed that the tiniest life forms are continually generated spontaneously from non-living organic matter, and that if the environment were constant, there would be a single and steady evolution of all things, increasing in complexity, along a determined course of progression. So in an ideal world, we would see all stages of life existing simultaneously -- as new life was continually generated and set off on its journey -- but the connections from simple to complex forms would be smooth and obvious.

However (still according to Lamarck) the fact is that the environment changes. And so, natural selection puts differing types and degress of pressure on these complexifying lineages, depending on place and time, so that they get deformed in various ways from the ideal, and thus species arise.

Darwin's insight was that natural selection was not a deformer in the process of evolutionary development, but in fact the very engine of evolutionary development.

[Cuddles]

However, the radio can be fixed and used again. But can humans be fixed after death (even if decay has not set in yet)? If the energy is still in the body, and decay has not been started (which takes about 72 hours to begin), then why cannot humans be restored as well?

How can the radio be fixed? If you break parts so it stops working you will have to replace them. We can do this with some parts of the human body as well, although others are too complicated for us at the moment. On the other hand if you take a human and a radio and hit them both until they stop moving I would really like to see how you get either of them to start working again without adding any new parts.

So we can tell what someone is thinking and what emotions they are feeling just by scanning the brain? Show me a study that reveals this.

That's quite obviously not what I said. We can detect the mind working with brain scans. At the moment the resolution is nowhere near good enough to read individula thoughts, and even if it ever is, everyone's brain is wired differently so everyone would have different brain patterns and no standard reading would be possible. There are some studies that show we can tell what someone is looking at when they are shown a few different pictures that have had the brain response already measured, but this is not very accurate, and in its current state not very useful. I'll let you do some of your own research here.

I was referring to fossils, that concreted the proof of the theory of evolution. Did Darwin see fossils that showed the connection between humans and primates, no. He came up with his theory, and later, fossils were found that became the hard proof for his theory.

Why do you think fossils are the only proof of evolution? Yes, fossils are good evidence for evolution, but there is much more that can be seen in living animals. Why do you think Darwin's finches are written about so much? They can be seen evolving over a few years. Although there is good evidence that Darwin never actually noticed them and based his ideas on mny other animals that could be seen to have evolved. Evolution had been around as an idea for years, and even natural selection as a method wasn't thought of, or published, by Darwin first. If you actually want to learn something rather than making uninformed complaints then "The Science of Discworld 3 - Darwin's Watch" gives a very good account of both evolution and Darwin's history.

Edit : see Piggy's post above.

The definition of a black hole, as I have always been told, is something so dense that nothing, not even light can escape it. However, there is thought among scientists in the field that some things can escape (see above reference that knowledge might be able to escape). Well, if something can except, then how does that fit into the standard description that nothing can escape? (The nothing can escape is from the school textbooks that I have read - so maybe their definition is out of date?).

Then, why are some scientists on the subject saying that "knowledge" can escape?

The definition is that a black hole is a body with an escape velocity greater than the speed of light in a vacuum. They are a logical consequence of any theory of gravity that also has a finite speed of light, so even though they are talked about with respect to relativity, even Newtonian mechanics says they must exist. Since they are very stange objects and can't be observed up close we don't know much about them, so obviously not everyone agrees on their exact properties, and some people will be wrong. There is no point asking questions like this if you are not willing to do some of your own research on the topic, since virtually everything told to the layperson is either incomplete or just plain wrong.

Okay. Can anyone recommend a good scientist journal that can be read online? Please do not say "library" since my local public library does not have that kind of stuff, and to use any college library, you need a student ID.

Nature or Science would be the obvious choices, but I don't know if you can get more than the abstracts without registering. Most journals are not free, so you are unlikely to find anything above a layperson level without paying quite a bit.

Oh yes, that. I never said that I could prove that belief (mine). And like I am saying here, it is not that I do not believe in black holes, it is just I do not see how they can be proven as what they claim to be where absolutely nothing escapes. So it is not that I do not believe in black holes, just I am not seeing that proof of "nothing escapes."

Have you actually looked for proof? Internet forums and popular science magazines are not the best places for detailed information. To really learn how black holes work you would probably need degree level courses in general relativity and quantum physics.

[Yllanes]

Nature or Science would be the obvious choices, but I don't know if you can get more than the abstracts without registering. Most journals are not free, so you are unlikely to find anything above a layperson level without paying quite a bit.

What about the arXiv (http://www.arxiv.org)? Most papers on theoretical physics and mathematics from the past 15 years are there. Of course, the papers are unintelligible for anyone without graduate level training and not the way to go if you want to learn phyics starting from a layman level.

[Cuddles]

What about the arXiv (http://www.arxiv.org)? Most papers on theoretical physics and mathematics from the past 15 years are there. Of course, the papers are unintelligible for anyone without graduate level training and not the way to go if you want to learn phyics starting from a layman level.

Ooo, I never knew about that. That's kind of useful considering I work in an accelerator. I wonder why I hadn't heard of that before.

[drkitten]

However, the radio can be fixed and used again. But can humans be fixed after death (even if decay has not set in yet)? If the energy is still in the body, and decay has not been started (which takes about 72 hours to begin), then why cannot humans be restored as well?

Not all radios are fixable, depending upon the complexity of the radio and the degree of damage. In many cases, "fixing" the radio requires replacing damaged parts with newly manufactured identical ones -- something that we can't yet do with human parts. Humans can indeed be fixed to some degree after "death," but they're sufficiently complicated (and parts are hard enough to get) that it's usually not possible.


So we can tell what someone is thinking and what emotions they are feeling just by scanning the brain? Show me a study that reveals this.

Why, yes, we can. Crudely. See, for example, this paper (http://www.neuroreport.com/pt/re/neuroreport/abstract.00001756-200403010-00029.htm;jsessionid=FP1fDycKqB1h61XjLG2RhHb2FhnTM V4LjcTvPLFJ1zQQjD7VT3gk!1209472165!-949856144!8091!-1)

"We investigated whether activity in limbic and paralimbic regions elicited by blocks of aversive (AV) and neutral (NEU) pictures can be detected by real-time fMRI. Real-time analysis of signal change during each block revealed that activations in insula and medial frontal cortex were more frequent during AV than NEU epochs. Single subject and group analysis off-line with conventional statistical parametric mapping methods matched the results obtained in real-time. Detecting cortico-limbic brain activation during perception and experience of emotionally salient visual stimuli with real-time fMRI technology is feasible."



The definition of a black hole, as I have always been told, is something so dense that nothing, not even light can escape it. However, there is thought among scientists in the field that some things can escape (see above reference that knowledge might be able to escape).

"Knowledge" isn't light.

[Yllanes]

Ooo, I never knew about that. That's kind of useful considering I work in an accelerator. I wonder why I hadn't heard of that before.

Eh? Why the hostility? I was not suggesting it for you, of course you know about that. You said:


Most journals are not free, so you are unlikely to find anything above a layperson level without paying quite a bit.


There actually are many technical papers free online. You know that, but other posters may not. In fact, I started my post with 'what about the arXiv?', because I was wondering why you hadn't mentioned it, not thinking that you weren't aware of its existence.

(Sorry for the derail everyone).

[Pup]

Yes, fossils are good evidence for evolution, but there is much more that can be seen in living animals. Why do you think Darwin's finches are written about so much? They can be seen evolving over a few years. Although there is good evidence that Darwin never actually noticed them and based his ideas on mny other animals that could be seen to have evolved.

Read it as "natural selection" with the emphasis on "natural," as opposed to "artificial," and another of Darwin's examples comes clear. He could see farmers artificially selecting what animals to breed, producing varieties of dogs or cattle with different traits. The leap in logic was that nature could make similar selections to alter animals.

[Nucular]

Oh yes, that. I never said that I could prove that belief (mine). And like I am saying here, it is not that I do not believe in black holes, it is just I do not see how they can be proven as what they claim to be where absolutely nothing escapes. So it is not that I do not believe in black holes, just I am not seeing that proof of "nothing escapes."

But now you understand the actual situation, yes? Personally, I've learned a lot about black holes on this thread; have you? And do you now see that black holes and paranormal claims are not particularly similar in the ways you originally thought they were?

[Nucular]

Eh? Why the hostility?

Hey Yllanes, just to say, I didn't read that as hostile or sarcastic - I thought Cuddles was quite genuinely surprised not to have come across that rather good resource you linked to.

[snooziums]

... If no such fossils had been found, Darwin's theory would have been in trouble.

That was basically what I was trying to say there. Before any fossils were found, it would have been much harder to prove Darwin's theory.

The fossil record is actually not the best evidence for Darwinian evolution. The hard proof came more from research in genetics and embryology.

True, I did not think about those. I was thinking about what was recorded in Darwin's time, it would have been hard to prove evolution, not what we know now.

And there is the butterflies in England that show a part of the evolution in action, however that was not observed until after Darwin's time. However, it is the best proof for evolution for me.

snooziums does not appear genuinely interested in learning anything about the scientific theories s/he purports to discuss. ...s/he would carefully consider the responses that others are posting, rather than continuing to bring out one uninformed snipe after another.

I am interested in learning more, and I do take into consideration the other replies. (See below).

How can the radio be fixed? If you break parts so it stops working you will have to replace them.

Still, at this time, if you replace parts in a human after they are dead, you cannot "restart" them back to life. But maybe someday... who knows.


Have you actually looked for proof? Internet forums and popular science magazines are not the best places for detailed information. ...

Yes, I have. That is why I ask for some place online to find scientific journals or articles to look for them.

Oh, and thanks for the links to those that posted them on where to find information. If you have any more, please let me know.

"Knowledge" isn't light.

It is something. So the idea that nothing escapes cannot hold true of "knowledge" does.

----

*sigh* Back to restating my question.

I was taught by my college textbooks and college professors that black holes were collapsed stars that were so dense that they has an infinite gravity pull to anything close. Once too close, nothing escape being sucked in. Nothing, nothing, nothing. And everything that was sucked in (including light) was destroyed (or converted into energy - however nothing remained intact).

To those textbooks and instructors, this was the definition of a black hole.

So, using the definition above, would it stand the challenge?

However... through this thread, I am seeing that maybe the "absolute truth" that I was taught might not be so absolute at all. With new ideas into what a black hole is, I am seeing that the constructs of it are still not totally clear. And even through what a black hole basically is does not change, how it works and what happens inside is still debated.

So, I have learned quite a bit from this thread. I guess to revise, I should have stated that would the absolute definition stated above (which was the only version I was taught), have passed?

But, that absolute version might not be so absolute.

[SirPhilip]

Hello everybody. This is my first post ever, please be gentle. It appears to me that the focus of this thread has moved from "would cutting edge scientific theory pass the challenge" to "what is scientific theory anyway?" Welcome to the forums. :)

So that you do not have to guess where I come from, I define myself as a rational thinker (I find skeptic too limiting a word) currently interested in finding whether the chi theories passed on to me by my martial arts masters can stand up to scrutiny. I am at the "favourably impressed" stage, I hope this does not authomatically make a woo of me in your eyes. Energy connotes potential to perform work, unless you are talking heat energy (http://www.hno.harvard.edu/gazette/2002/04.18/09-tummo.html), which can be produced by some forms of internal martial arts which involve being able to control the stem brain and regulate body temperature; a very useful skill if you live in cold climates.

Having came across references to the work of Dr Leonard Wisneski (Professor of medicine at George Washington University and a fellow of the American College of Physicians) on the human energy field, I would appreciate comments from anybody familiar with his work and opinions whether it can be put in the "cutting edge scientific theory" basket or not.
Does anybody take him seriously (his qualifications are impressive enough) or not? If not why? The mixture of scholarship and amateurishness of a place like this can't be helped, but could you pleeeease be thorough in quoting your sources? (relying on wikipedia, how embarrassing!)
Thanks in advance. As a scientific initiative, this would simply involve a new understanding of how the body can utilize alternative forms of power besides that derived from food, so my guess would be "maybe".

[Skeptic Ginger]

Ok, obviously you need to read up a little more on black holes before you go opining on them.

....Piggy, you just think on the same wavelength as I do.

This is just what the woo believers do. They are convinced they understand something and in that understanding, they have all sorts of mistaken information or mistaken conclusions about the information. "Therefore yadda yadda yadda..."

One needs at least a basic understanding of the science, whatever the field, before one is really able to discuss it at the level of claiming there is no direct evidence, or we can't see it therefore the evidence is imaginary.

This doesn't mean one can't rely on the discussion of experts who do know the science. I trust the astronomers know how to measure gravity, how to test single photons, how to understand some complicated analysis of radio waves depicting the leftover radiation from the Big Bang or X-rays from the most distant areas of the Universe. And of course there are competing theories and theories which have little conclusive evidence.

There is more than sufficient evidence supporting the existence of black holes. We see them via various means. We knew viruses existed before the electron microscope allowed us to see pictures of them. You could take some fluid with the virus in it and infect something else.

String theory is not sufficiently tested. It is a proposed theory to explain the observed phenomenon. It has to result in predictions and the predictions must be tested and confirmed. There's a long way to go there.

I know others have elaborated on these issues far more extensively than my meager understanding.

But be careful not to confuse evidence you don't understand that other people do understand with no evidence at all.

[Thinktoomuch]

After 25:05 hours of silence I am very grateful for your welcome and explanation of an acceptable approach to the research of chi (ki, prana, whatever):

As a scientific initiative, this would simply involve a new understanding of how the body can utilize alternative forms of power besides that derived from food, so my guess would be "maybe".[/quote]

The problem is that, to my knowledge, the very existence of this alternative form of power is not yet proven to the Foundation's satisfaction. Is Dr Wisneski work to its standard? Or did I get this wrong, and the Foundation is only after the quacks that pretend without evidence to manipulate this form of power?

[steenkh]

Thinktoomuch,

Your post drowned in the general flow of the thread. You should open a new thread on the subject of chi in martial arts. I can assure you that it will attract more attention there, but it will be seen as a distraction here! There are several martial arts people on the forums.

I have no specialised knowledge in the field, so I can only say that the general thinking here is that chi is just ********. Before new theories on chi are considered, it should be proven that chi exists.

And welcome to the forums!

[Piggy]

I am seeing that the constructs of it are still not totally clear.
I hate to sound like a broken record, but the "constructs of it" are totally clear.

There is no controversy at all over what a black hole is.

This doesn't mean there are not still questions to be answered.

I mean, there is no doubt who Michael Jackson is, even though there are a lot of unanswered questions about his life.

That may seem like a flippant example, but it's not. Think about it.

Just because there are questions to be asked, new truths to be discovered, and lots of people actively engaged in asking these questions and searching for these truths... this does not at all imply that the object in question isn't clearly defined.

In fact, I believe that the explanation I gave above is pretty darn clear -- both specific and unambiguous. If you want it more specific than that, you'll have to ask a specialist, and you won't understand the answer.

For you to continue to claim that black holes are not well-defined entities, or that there is some scientific controversy over what they are (not merely over whether certain objects we've detected are black holes), is disingenuous or merely dogmatic.

[Thinktoomuch]

That was exactly my question. Is Dr Wisneski, from the top ranks of the US medical profession, just talking ******** or doing science? I'll take your advice and start a new thread, it's going nowhere from here. Thanks.

[drkitten]

I was taught by my college textbooks and college professors that black holes were collapsed stars that were so dense that they has an infinite gravity pull to anything close. Once too close, nothing escape being sucked in. Nothing, nothing, nothing. And everything that was sucked in (including light) was destroyed (or converted into energy - however nothing remained intact).

You obviously didn't understand the material.

You're focusing too much on "nothing." "Knowledge," in this sense, is indeed nothing -- it has no mass-energy. I suspect that either you didn't understand the instructors and textbooks, or else they had deliberately simplified to avoid having to explain in too much detail.


However... through this thread, I am seeing that maybe the "absolute truth" that I was taught might not be so absolute at all.

Almost certainly. Any textbook has to simplify, because you have to summarize in a few hundred pages what has been discussed in several thousand journal pages.

Another way of putting it is that textbooks are always wrong. But they're close enough to right that you can get a better understanding. The 'constant' acceleration of gravity isn't, because the Earth isn't a uniform sphere. But treating 'g' as a constant makes sense for understanding physics class, since the only people who really care about variations in the acceleration of gravity are high-end researchers and rocket scientists.

[Cuddles]

Eh? Why the hostility? I was not suggesting it for you, of course you know about that.

Hey Yllanes, just to say, I didn't read that as hostile or sarcastic - I thought Cuddles was quite genuinely surprised not to have come across that rather good resource you linked to.

Thanks Nucular, that's exactly what I meant.

[Cuddles]

That was basically what I was trying to say there. Before any fossils were found, it would have been much harder to prove Darwin's theory.

True, I did not think about those. I was thinking about what was recorded in Darwin's time, it would have been hard to prove evolution, not what we know now.

And there is the butterflies in England that show a part of the evolution in action, however that was not observed until after Darwin's time. However, it is the best proof for evolution for me.

If you accept the butterflies (I assume you mean the ones turning black because of smoke), why don't you accept that there are other example that you don't know about? There are many different examples of species changing that were documented around that time, which is exactly why evolution was being thought about. The finches are probably the most commonly used example, but if you look closely at Darwin's work, and that of most naturalists around that time, you will find many different examples.

In addition, fossils provide very good evidence for evolution, but a lack of fossils would not have been evidence against. For fossilzation to occur, very specific conditions are needed, which is why so few things are become fossils. If no fossils existed, all we would be able to say is that there was no process that could preserve animals for millions of years. This would mean some useful evidence in favour of evolution would be missing, but would in no way be against evolution at all.

I was taught by my college textbooks and college professors that black holes were collapsed stars that were so dense that they has an infinite gravity pull to anything close. Once too close, nothing escape being sucked in. Nothing, nothing, nothing. And everything that was sucked in (including light) was destroyed (or converted into energy - however nothing remained intact).

To those textbooks and instructors, this was the definition of a black hole.

So, using the definition above, would it stand the challenge?

No. The idea of a black hole, as has already been stated, is a logical consequence of a finite speed of light. Given this, an object with strong enough gravity will prevent even light escaping, which we call a black hole. There may be arguments about exactly how they work and whether there are funny ways to get somehow escape, but there is nothing vaguely paranormal about them.

However... through this thread, I am seeing that maybe the "absolute truth" that I was taught might not be so absolute at all. With new ideas into what a black hole is, I am seeing that the constructs of it are still not totally clear. And even through what a black hole basically is does not change, how it works and what happens inside is still debated.

This is what Terry Pratchett calls "Lies to children". It is impossible to really understande black holes without a very deep understanding of relativity and quantum physics. Without this you can still understand the basic concept of something with really strong gravity, but you will never be able to understand the actual reality. This is true for virtually everything taught in school, and even many things at degree level. Usually, a good teacher or textbook will make it clear that they are not telling the absolute truth, but if they don't can be easy to be mislead into thinking that you understand more than you actually do.

[Yllanes]

Thanks Nucular, that's exactly what I meant.

Then I am sincerely sorry for taking it the wrong way.

Check the arXiv sometime, it is an invaluable resource. It not only contains the paper, but also hyperlinked lists of all the others that have cited it or are cited by it and many more interesting statistics.

[Piggy]

"Knowledge," in this sense, is indeed nothing -- it has no mass-energy.
I think snooziums may be refering to "information", as defined by information theory, and simply mis-remembering it as "knowledge". Since the formation of a black hole would destroy anything capable of being conscious, there's no reason to believe there's any "knowledge" inside to escape in the first place.

But snooziums, I would not recommend that you dive into information theory -- talk about a head-spinner! It ain't for the squeamish. Stick with the basic physics for now.

[nathan]

No. The idea of a black hole, as has already been stated, is a logical consequence of a finite speed of light.
.. and that light is something that has non-zero gravitational mass? Which IIRC was a surprise to classical physics. I'm not sure if there are any other necessary preconditions to the idea of a black hole.

[Cuddles]

.. and that light is something that has non-zero gravitational mass? Which IIRC was a surprise to classical physics. I'm not sure if there are any other necessary preconditions to the idea of a black hole.

Hmm, good point. I think light was thought of as possibly having non-zero mass before relativity, since it was realised that anything moving at a finite speed must also have finite mass due to the laws of momentum and inertia. I think Newtonian mechincs predicited light would bend under gravity, just not by the right amount. It wasn't really possible to measure any of this until around the time relativity was thought up, so it was never more than a curiosity, and since no-one knew what stars were, no-one ever thought of black holes.

[drkitten]

Hmm, good point. I think light was thought of as possibly having non-zero mass before relativity, since it was realised that anything moving at a finite speed must also have finite mass due to the laws of momentum and inertia.

Huh?

I don't think that this was believed at all. The idea that light had momentum would have been considered ludicrous in 1900.

[nathan]

I think light was thought of as possibly having non-zero mass before relativity, since it was realised that anything moving at a finite speed must also have finite mass due to the laws of momentum and inertia. I think Newtonian mechincs predicited light would bend under gravity, just not by the right amount.

I think Newton argued that light was particle like, but I don't think that was accepted. I do vaguely recall what you say about Newton predicting light bending under gravity. Light was thought of as a wave until (a) attempts to measure the aether in which it propagated failed, (b) Einstein explained the photo electic effect and (c) probably some other stuff I'm neglecting.

I'm curious about the argument that finite speed == non-zero mass. Oh, I get it. If the object has zero mass, then any force accelerating it would accelerate it to infinite speed.

[Yllanes]

Hmm, good point. I think light was thought of as possibly having non-zero mass before relativity, since it was realised that anything moving at a finite speed must also have finite mass due to the laws of momentum and inertia. I think Newtonian mechincs predicited light would bend under gravity, just not by the right amount. It wasn't really possible to measure any of this until around the time relativity was thought up, so it was never more than a curiosity, and since no-one knew what stars were, no-one ever thoug
ht of black holes.

Back then they weren't really sure whether light had mass, but some people reasoned assuming it did. For example, John Michell and Laplace imagined a star so dense that its escape velocity would be greater than that of light. If light were affected by gravity, they said, it would have to return to the very star that was emitting it. But no one payed much attention to these ideas.

You can calculate the angle of deflection for light rays by the Sun using Newtonian mechanics. The result is close to the real value (with 'real' I mean both relativistic and empirical). It is a simple and quite short excercise. You can even calculate the Schwarzchild radius of a black hole using Newtonian mechanics. In this case, the value is exactly the same as the relativistic one.

But in doing these things we are cheating. The truth is that Newtonian mechanics is, we now know, incompatible with a finite speed for the propagation of light. In other words, for Newtonian physics to be consistent c must be infinite.

Huh?

I don't think that this was believed at all. The idea that light had momentum would have been considered ludicrous in 1900.

James Clerk Maxwell calculated the expression for the radiative pressure in the 1870s.

[William Smith]

Hiya

I am wondering how many "scientific" theories would hold up to the million dollar challenge. For example, no one has been able to prove that black holes exist, worm holes, or even the "string theory." Yet, many scientists still accept them as facts.

I have yet to see a working example of a black hole, or any hard evidence that any exist. So why are there not skeptics for these theories within the scientific community?

Just a thought.

Would a spell checked thread title ensure some credibility?

Yes, this is bitchin' de luxe. So what?

[nathan]

... lots of good stuff ...
thanks!