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## Main Question or Discussion Point

Can somebody comment on the following paper: http://arxiv.org/abs/hep-th/0702115" [Broken]

As I was able to understand the paper, this 'entropic principle' was applied to the initial condition/physical parameters/cosmological constant selection, which is a rather grand scale. Can the same principle be applied to a smaller scale of elementary quantum event outcomes (would more 'entropic' outcome be more probable)?

Here are some (disrespectful?) comments in the blogosphere: http://resonaances.blogspot.com/2007/08/entropic-principle.html" [Broken]Abstract: We compute the expected value of the cosmological constant in our uni-

verse from the Causal Entropic Principle. Since observers must obey the laws of thermo-

dynamics and causality, the principle asserts that physical parameters are most likely to

be found in the range of values for which the total entropy production within a causally

connected region is maximized. Despite the absence of more explicit anthropic crite-

ria, the resulting probability distribution turns out to be in excellent agreement with

observation. In particular, we find that dust heated by stars dominates the entropy pro-

duction, demonstrating the remarkable power of this thermodynamic selection criterion.

The alternative approach—weighting by the number of “observers per baryon”—is less

well-defined, requires problematic assumptions about the nature of observers, and yet

prefers values larger than present experimental bounds.

As I was able to understand the paper, this 'entropic principle' was applied to the initial condition/physical parameters/cosmological constant selection, which is a rather grand scale. Can the same principle be applied to a smaller scale of elementary quantum event outcomes (would more 'entropic' outcome be more probable)?

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