Monday, August 30, 2010

Verlinde videos on emergent gravity

Reading the kea's new blog I advertised that there were two videos of Verlinde talking about emergent gravity:

1)KIPT video

2) Perimeter video

At the beginning of this summer Verlinde had announced it's presence in a string theory conference in Madrid but, unfortunately, at last he didn't assist. Because of that I was curious to see in video what I missed in direct and looked at the first of the videos. The realization is somewhat poor in various moments and you can't see Verlinde typing equations in the blackboard or you can't see complete the slides. Still you can follow the conference so it is ok.

In the conference he argues some thing that dn't appear in his paper On the Origin of Gravity and the Laws of Newton. Searching on verlinde's papers n arxiv one can find that some of the things he says on the conference about Berry phase or Born-Oppenheimer/adiabatic could be somewhat rooted on this other paper: Black Hole Berry Phase

While watching the video I have got the impression that it could be interesting to see it one could get an alternative construction of general relativity using entropy instead of geometry as the way to go from special relativity, that is, constant speed reference systems, to accelerated systems. In particular I thought about it when Verlinde does sme considerations about Rindler space.

If that would be possible one would have a different way to consider the questions of general relativity. Also if that entropic viewpoint of general relativity makes sense one could use as a framework to formulate actual theories, including string theory, and, maybe, it could seed some light on it. In that sense it would be more an entropic formulation of general relativity that anything else.

Of course he last two paragraphs are just my considerations, and wouldn't be confused with what Verlinde says.

To end this entry just to mention that a few days ago Peter G.O. Freund posted the paper Emergent Gauge Fields where he argues that the entropic force scenario for gravity could mean, because of ADS/CFT, that all other forces are emergent. The paper is discussed in Peter WOits blog Everything is Emergent. Verlinde mentions similar things at the end of the talk.

Well, as I said in my previous post about entropic gravity I agree with the common view that this idea is very vague. Still I liked the talk over the paper. Even if the idea of gravity through entropy fails the talk is entertaining and worth to watch.


Matti Pitkanen said...

I do not find it difficult to take seriously the idea that gauge bosons emerge as fermion pairs so that only fermions would be fundamental. In my personal Universe bosons emerge as pairs of fermion and anfifermion at opposite throats of wormhole contacts (something different from those of General Relativity). The idea about emergence of space-time does not make much sense to me.

Javier said...

Hi Mattri, welcome. Maybe it would be interesting that you would explain, with all the maths, how that wormholes of your theory are ;).

I neither am specially enthusiastic with the "emergent" hype. I don't even understand how those people pretend to view general relativity,that needs ten degrees of freedom (the components of a symmetric metric) reduced to one (an scalar entropy), I neither understand how they want to reduce an dynamic theory to equilibrium thermodynamic.

Still I find it could be a good idea to try a reformulation of generality (even if it fails). Maybe some interesting lessons could be learned.