Do I understand at all what Verlinde is saying?

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SUMMARY

The discussion centers on the interpretation of Prof. Erik Verlinde's proposal that gravitational force can be derived from entropy. Participants reference key concepts from "Principles of Physical Cosmology" by P.J.E. Peebles and the Boltzmann definition of entropy. The conversation highlights the relationship between entropy and the expansion of space, specifically questioning whether invoking entropy also implies invoking Hubble's law. The holographic screen is discussed as a critical element that influences an ensemble's entropy, suggesting that changes in entropy due to spatial expansion can lead to perceived gravitational effects.

PREREQUISITES
  • Understanding of General Relativity
  • Familiarity with the concept of entropy in thermodynamics
  • Knowledge of Hubble's law and cosmic expansion
  • Basic comprehension of the holographic principle
NEXT STEPS
  • Research the implications of entropy in gravitational theories
  • Study the holographic principle and its relation to quantum gravity
  • Examine the relationship between entropy and cosmic expansion in cosmology
  • Explore the works of Prof. Erik Verlinde on emergent gravity
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Physicists, cosmologists, and students of theoretical physics seeking to understand the intersection of entropy and gravity, as well as those interested in modern interpretations of gravitational theories.

Jimster41
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It would be nicer if you had posted the text and references directly as there is no easy way to click on your links while they embedded in your image.

PF supports latex so you have posted it that way.
 
I posted as a .png file because the Daum Equation Editor "Tex" output wasn't friendly to the interpreter here. Not sure why. Still trying to figure out why the Daum Tex output is picky.

The references are totally stock. I have not manipulated them at all. I thought they would be pretty recognizable:

for "Spacetime" and "Hubble" expansion I'm quoting directly from
"Principles of Physical Cosmology", P.J.E. Peebles Princeton University Press, 1993 pp 11,71

For General Relativity statement I just quote a layman's definition, that I thought was complete enough for the purpose.

For Entropy I went to Wiki and plucked the stock "Boltzmann" version. Again I was imagining these would be pretty recognizable statements from the Standard Model and wouldn't need much reference. I am not manipulating them at all, or trying to say anything new. I'm just trying to understand what pieces of existing theory Prof. Verlinde is putting together - to derive gravitational force from entropy.

The big question, just trying to get some sense of what he's proposing: Is invoking Entropy also invoking Hubble? I thought this was the key part of his argument... I interpreted the holographic screen as a barrier between state i and state j that an ensemble even at rest in space must cross (in time), and which has the critical effect of changing that ensemble's entropy. Space is expanding, clock ticks, Ensemble's entropy has changed just because it is now spread across more possible states. If entropy is changed then there is an acceleration of that ensemble (changed relative probability of arrangement i) even when at rest, and it therefore experiences force and is considered to have mass.
 
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