Daily Archive for July 13th, 2010

In the New York Times this week there’s an article* by Dennis Overbye on Erik Verlinde and his paper on the idea that gravity is not a force at all, but a consequence of thermodynamics. You can think of it as an extreme take on one of the directions a lot of the research (that I’ve mentioned a number of times has been going on in string theory) has been pointing, although I think it is safe to say that there’s a lot to be done on making the statement a concrete one that you can do physics with. I think it contains the germs of the right thing we’re all reaching for, but does not quite get there yet. We’re now quite routinely formulating some of the key physics of gravity entirely as physics of a completely non-gravitational dual theory – this is the content of what we call holography – and in particular the quantum physics of black holes in those settings get holographically mapped to the thermodynamics of the non-gravitational physics. This is the basis of the tools that we’ve been applying to studying aspects of phenomena showing up in various experimental systems in nuclear physics and cold atomic physics (and studies of phenomena relevant to various condensed matter systems are also being done). I’ve told you about a lot of this in various posts. (Some of them are listed below.) Running this the other way, the model non-gravitational systems (certain gauge theories at strong coupling and with large rank gauge groups) can be thought of as examples of how gravity (and space-time itself) is really an emergent phenomenon, appearing simply as Continue reading ‘Emerging Gravity’