John Wheeler's Legacy: Einstein v. Wheeler's Black Holes

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Discussion Overview

The discussion centers on the legacy of John Wheeler in relation to black holes, contrasting his views with those of Albert Einstein. Participants explore the implications of Wheeler's contributions to the concept of black holes and the associated challenges to relativistic physics, including the nature of singularities and the formation of black holes.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants argue that Wheeler's acceptance of black holes represents a deviation from Einstein's original theories, suggesting that Einstein believed "Schwarzschild singularities do not exist in physical reality."
  • Others challenge the notion that black holes cannot form, asserting that black holes are dense objects from which not even light can escape, and that their existence is supported by observational evidence.
  • A participant highlights a distinction between an object crossing the event horizon of a black hole and the arrival of information about that crossing at a distant location, questioning the clarity of earlier statements.
  • Another participant emphasizes that the issues surrounding black holes relate more to the physics after their formation rather than their formation itself, suggesting that coordinate systems in relativity can be chosen to avoid singularities at the horizon.

Areas of Agreement / Disagreement

Participants express disagreement regarding the nature and existence of black holes, with some supporting Wheeler's perspective and others defending the formation and reality of black holes as consistent with observations. The discussion remains unresolved.

Contextual Notes

Limitations include differing interpretations of relativistic physics, the dependence on specific coordinate systems, and the unresolved status of singularity theorems in the context of black holes.

Max Wallis
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Einstein v. Wheeler's Black Holes

John Wheeler who died earlier this month (13 April) not only coined the term
'black hole', but is of course closely identified with the very concept of a
gravitationally collapsed object.

So he surely carries much of the blame for the basic deviation from
sound relativistic physics. Of Einstein's two major contributions,
the special theory means that nothing can travel faster than light,
while the general theory means nothing can get into a 'black hole'.

The latter is because the extreme distortion of space time at the
event horizon of an imagined black-hole forces an object to take
infinite time to reach it, as seen by a distant observer. Einstein
himself derived on the basis of a dust cloud model that:
"Schwarzschild singularities do not exist in physical reality" (Ann. Math.
40, 922-936, October 1939).

Ths problem has recently been solved more completely in
"Gravitational waves versus black holes" at <arXiv.org/abs/0707.0201>.

If Wheeler and the mainstream physics community had accepted that
black holes cannot form, relativity would have been consistent but
lost much of its glamour. Speculations about a black hole's
interior, or two connected by a "wormhole" constituting parallel
universes, or merging black holes as a gigantic energy source would
all be ruled out of court.

With the passing of John Wheeler, can relativistic gravitational
physics shed its speculative deviations from Einstein's realist
heritage <crisisinphysics.co.uk> ?

Max Wallis,
Cardiff University
 
Physics news on Phys.org
Max Wallis said:
Einstein v. Wheeler's Black Holes

John Wheeler who died earlier this month (13 April) not only coined the term
'black hole', but is of course closely identified with the very concept of a
gravitationally collapsed object.

So he surely carries much of the blame for the basic deviation from
sound relativistic physics. Of Einstein's two major contributions,
the special theory means that nothing can travel faster than light,
while the general theory means nothing can get into a 'black hole'.

The latter is because the extreme distortion of space time at the
event horizon of an imagined black-hole forces an object to take
infinite time to reach it, as seen by a distant observer.
Einstein
himself derived on the basis of a dust cloud model that:
"Schwarzschild singularities do not exist in physical reality" (Ann. Math.
40, 922-936, October 1939).

[snip]

Max Wallis,
Cardiff University

I highlighted the section that doesn't make sense to me.
There's a difference between "an object crossing the horizon"
and "the arrival of information at some distant location that the crossing occurred."

Are you aware of the "singularity theorems"?
 
Max Wallis said:
If Wheeler and the mainstream physics community had accepted that
black holes cannot form, relativity would have been consistent but
lost much of its glamour.

Well... if you believe in any form of relativity, then surely you can't favour one coordinate system over another. Basic relativity says that spacetime is perfectly well behaved at the horizon, and you are free to pick a coordinate system in which things don't blow up. Yes, a single coordinate system doesn't describe both observers very well, but black holes aren't special in this regard. You could talk about an accelerating observer and the rindler coordinates and get the same effect.

Please don't confuse pitfalls of basic differential geometry with actual physics problems. The problems with black holes have nothing to do with them forming, but all about what happens after they form.

Cheers
 
Max Wallis said:
Einstein v. Wheeler's Black Holes

John Wheeler who died earlier this month (13 April) not only coined the term
'black hole', but is of course closely identified with the very concept of a
gravitationally collapsed object.

So he surely carries much of the blame for the basic deviation from
sound relativistic physics. Of Einstein's two major contributions,
the special theory means that nothing can travel faster than light,
while the general theory means nothing can get into a 'black hole'.

The latter is because the extreme distortion of space time at the
event horizon of an imagined black-hole forces an object to take
infinite time to reach it, as seen by a distant observer. Einstein
himself derived on the basis of a dust cloud model that:
"Schwarzschild singularities do not exist in physical reality" (Ann. Math.
40, 922-936, October 1939).

Ths problem has recently been solved more completely in
"Gravitational waves versus black holes" at <arXiv.org/abs/0707.0201>.

If Wheeler and the mainstream physics community had accepted that
black holes cannot form, relativity would have been consistent but
lost much of its glamour. Speculations about a black hole's
interior, or two connected by a "wormhole" constituting parallel
universes, or merging black holes as a gigantic energy source would
all be ruled out of court.

With the passing of John Wheeler, can relativistic gravitational
physics shed its speculative deviations from Einstein's realist
heritage <crisisinphysics.co.uk> ?

Max Wallis,
Cardiff University

Black holes can form. Its simply an error to think of black holes as singularities. A black hole is an object so dense that not even light can escape. All the matter is contained within the Schwarzschild radius (or at least very close to it). The reason that no fine point is made regarding this is because an outside observer cannot determine the mass distribution. The matter that is outside the black hole (just a tad outside the Schwarzschild radius radius) cannot be observed because light coming from it is too far redshifted to observe. That they do exist is a matter of observation. The existence of a black hole at the center of our galaxy is consistent with observation. Also, micro black holes, if they do exist, never formed but have existed since the beginning of the universe.

Pete
 

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