Erik Verlinde gave this great talk at Perimeter on Wednesday last week, which is online as video. It was at a recent Holo Cosmo workshop they had there(adsbygoogle = window.adsbygoogle || []).push({});

http://pirsa.org/C11010

It is a very exciting talk. He is actively grasping for what many people dream about: a concrete way to think of geometry and matter as the same thing---just different aspects of "it".

Geometry and matter growing up from the same hidden phase space roots.

And he has ideas of how both inertia and the gravitational force arise.

http://pirsa.org/11060065/

The Hidden Phase Space of our Universe

Erik Verlinde

By combining insights from black holes and string theory we argue for the existence of a hidden phase space associated with an underlying fast dynamical system, which is largely invisible from a macroscopic point of view. The dynamical system is influenced by slow macroscopic observables, such as positions of objects. This leads to a collection of reaction forces, whose leading order Born Oppenheimer force is determined by the general principle that the phase space volume of the underlying system is preserved. We propose that this adiabatic force is responsible for inertia and gravity. This fact allows us to calculate the hidden phase space volume from the known laws of inertia and gravity. We find that in a cosmological setting the appearance of dark energy is naturally explained by the finite temperature of the underlying system. The adiabatic approximation that leads to the usual laws of inertia and gravity breaks down in the neighborhood of horizons. In this regime the reaction force degenerates into an entropic force, and the laws of inertia and gravity receive corrections due to thermal effects. A simple estimate of these effects leads to the conclusion that they coincide with observed phenomena attributed to dark matter.

Date: 22/06/2011 - 9:00 am

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# *Hidden Phase Space* at the Holo Cosmo corral (Verlinde video)

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