[ccvannorman]

I absolutely love this question.

Postulate: You cannot define a largest physically describable number.

My assumption is that due to the very nature of Kolmogorov complexity (and other Godel related / halting problem related / self referential descriptions), this is not an answerable or sensible question.

It falls under the same language-enabled recursion problems as:

- The least number that cannot be described in less than twenty syllables. - The least number that cannot be uniquely described by an expression of first-order set theory that contains no more than a googol (10^100) symbols.