A Copenhagen solution of the black hole singularity problem

Click For Summary

Discussion Overview

The discussion revolves around the black hole singularity problem, particularly from the perspective of the Copenhagen interpretation of quantum mechanics. Participants explore the implications of strong gravitational tidal forces on observers and measuring devices, the nature of singularities, and the relationship between quantum mechanics and general relativity in the context of black holes.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants argue that the singularity cannot be observed due to strong tidal forces that would destroy any observer or measuring apparatus before reaching it.
  • Others challenge this view by suggesting that it leads to problematic implications, such as denying the existence of matter outside the observable universe.
  • One participant states that the singularity is in the future of any falling observer and is space-like, thus unobservable.
  • Another viewpoint suggests that for sufficiently large black holes, tidal forces can be manageable, but this does not apply at the singularity itself.
  • Some participants discuss the implications of the Copenhagen interpretation, noting that physical properties may not be defined before measurement, which contrasts with general relativity's treatment of singularities.
  • A later reply references a discussion in Wald's work about quantum coherence and measurement theory, suggesting that there may be frameworks that reconcile these issues.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the nature of the black hole singularity and its observability. There is no consensus on whether the Copenhagen interpretation provides an acceptable solution to the singularity problem.

Contextual Notes

Participants highlight limitations in understanding the properties of tidal forces and the implications of measurement theory in the context of black holes, indicating unresolved aspects of the discussion.

Demystifier
Science Advisor
Insights Author
Messages
14,720
Reaction score
7,317
Due to strong gravitational tidal forces, any living observer will die and any macroscopic measuring apparatus will be destroyed before it reaches the black hole singularity at the center of a macroscopic black hole. Hence the black hole singularity cannot be observed, so from an experimental point of view it doesn't exist.

Is that an acceptable solution of the black hole singularity problem from a "Copenhagen" point of view?
 
Physics news on Phys.org
By that argument, we could say matter outside the observable universe doesn't exist? Or matter inside but far away stopped existing since we are not in its future light cone any more? I don't share that view. It also doesn't answer how the end of the evaporation process looks like.
 
Its characteristics are not defined.
 
There is not black hole singularity problem.

Also, the tidal forces don't matter. The singularity is in the future of any falling observer and space-like, so it cannot be observe.
 
If the black hole is large enough, I have read that the tidal forces are manageable.
 
akvadrako said:
If the black hole is large enough, I have read that the tidal forces are manageable.
Not at the singularity, by definition. At the event horizon, tidal forces are indeed lower for a larger hole, but this is not what Demystifier is talking about. Somewhere between horizon and singularity the tidal forces get sufficiently high to rip you apart (assuming GR holds).
 
Last edited:
  • Like
Likes   Reactions: akvadrako and Demystifier
In the CI it is not generally assumed that the tidal waves have definite properties before observation. It's silent on the matter and we must assume that they have those properties(though this is common and probably wrong).
 
Demystifier said:
Hence the black hole singularity cannot be observed, so from an experimental point of view it doesn't exist.

Is that an acceptable solution of the black hole singularity problem from a "Copenhagen" point of view?
I don't think these views are comparable at all. According to the CI physical properties are not defined before measurement whereas General Relativity requires that physical quantities become infinite at the singularity which is unobservable per se .
 
Demystifier said:
Due to strong gravitational tidal forces, any living observer will die and any macroscopic measuring apparatus will be destroyed before it reaches the black hole singularity at the center of a macroscopic black hole. Hence the black hole singularity cannot be observed, so from an experimental point of view it doesn't exist.

Is that an acceptable solution of the black hole singularity problem from a "Copenhagen" point of view?

In section 7.3 of "Quantum Field Theory in Curved Spacetime and Black Hole Thermodynamics", Wald discusses issues of quantum coherence that are especially (but not exclusively) prominent in the process of black hole evaporation. Specifically, it is hard to correlate states defined on spacetime surfaces in different regions in the presence of black hole evaporation. I don't think your proposal would solve this issue.

On the other hand, in the same book, Wald also discusses measurement theory formulated with an algebraic approach (i.e. where states are no longer defined on spacetime surfaces) that would presumably let us recover a Copenhagen interpretation. So maybe there's no problem in the first place.
 

Similar threads

  • · Replies 20 ·
Replies
20
Views
4K
  • · Replies 18 ·
Replies
18
Views
2K
  • · Replies 16 ·
Replies
16
Views
4K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 57 ·
2
Replies
57
Views
4K
  • · Replies 7 ·
Replies
7
Views
4K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 20 ·
Replies
20
Views
3K
  • · Replies 17 ·
Replies
17
Views
4K
  • · Replies 22 ·
Replies
22
Views
2K