Entropic Accelerating Universe (Smoot et al)

[marcus]

Thanks for spotting today's Easson Frampton Smoot et al followup!

Now they have an explanation for inflation! as well as an alternative to dark energy.

 

[MTd2]

Didn't I tell you they just needed a more accurate approximation to find something better! Now, let's wait for the (bounce at) big rip

 

[marcus]

What is getting the most attention about the entropic force idea is it's application to cosmology---first to explain today's accelerated expansion ("dark energy" effect) and then to explain early universe accelerated expansion ("inflation").

Without needing to imagine either a made-up dark energy field, or an inflaton field.

Now today Modesto and Randono posted a new entropic force paper which has possible relevance both to the problem of TESTING the idea, by predicting corrections to Newton law, and also to cosmology as well. MTd2 spotted this earlier today.

http://arxiv.org/abs/1003.1998
Entropic corrections to Newton's law
Leonardo Modesto, Andrew Randono
7 pages, 2 color figures
(Submitted on 9 Mar 2010)
"It has been known for some time that there is a deep connection between thermodynamics and gravity, with perhaps the most dramatic implication that the Einstein equations can be viewed as a thermodynamic equation of state. Recently Verlinde has proposed a model for gravity with a simple statistical mechanical interpretation that is applicable in the non-relatvistic regime. After critically analyzing the construction, we present a strong consistency check of the model. Specifically, we consider two well-motivated corrections to the area-entropy relation, the log correction and the volume correction, and follow Verlinde's construction to derive corrections to Newton's law of gravitation. We show that the deviations from Newton's law stemming from the log correction have the same form as the lowest order quantum effects of perturbative quantum gravity, and the deviations stemming from the volume correction have the same form as some modified Newtonian gravity models designed to explain the anomalous galactic rotation curves."