randomness in nature - MathOverflow [closed] most recent 30 from http://mathoverflow.net 2013-05-23T05:03:15Z http://mathoverflow.net/feeds/question/9369 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/9369/randomness-in-nature randomness in nature liza 2009-12-19T14:51:15Z 2010-02-05T12:12:42Z <p>What is the explanation of the apparent randomness of high-level phenomena in nature? For example the distribution of females vs. males in a population (I am referring to randomness in terms of the unpredictability and not in the sense of it necessarily having to be evenly distributed). 1. Is it accepted that these phenomena are not really random, meaning that given enough information one could predict it? If so isn't that the case for all random phenomena? 2. If there is true randomness and the outcome cannot be predicted - what is the origin of that randomness? (is it a result of the randomness in the micro world - quantum phenomena etc...)</p> <p>where can i find resources about the subject?</p> http://mathoverflow.net/questions/9369/randomness-in-nature/9371#9371 Answer by Gil Kalai for randomness in nature Gil Kalai 2009-12-19T15:04:23Z 2010-02-05T12:12:42Z <p>This is, of course, a very important problem. One (extreme) point of view is that any form of classical (=commutative) randomness reflects "only" human uncertainty and does not have an "objective" physical meaning. </p> <p>(Further answers to this question and more discussion are welcome on <a href="http://gilkalai.wordpress.com/2009/12/27/randomness-in-nature/" rel="nofollow">the posting entitled "Randomness in nature" on my blog "Combinatorics and More"</a>. Here is a link to a <a href="http://gilkalai.wordpress.com/2010/01/20/randomness-in-nature-ii/" rel="nofollow">subsequent post with further discussion</a>.) Some related material can be found in the site of the conference "<a href="http://www.vanleer.org.il/probability/1-home.htm" rel="nofollow">The Probable and the Improbable: The Meaning and Role of Probability in Physics</a>". </p> http://mathoverflow.net/questions/9369/randomness-in-nature/9372#9372 Answer by jrshipley for randomness in nature jrshipley 2009-12-19T15:32:47Z 2009-12-19T15:32:47Z <p>You might be interested in Poincare's method of arbitrary functions for establishing probability distributions on "random" mechanical events. A quick search turned up this article by Jan van Plato: <a href="http://bjps.oxfordjournals.org/cgi/pdf_extract/34/1/37" rel="nofollow">http://bjps.oxfordjournals.org/cgi/pdf_extract/34/1/37</a></p> http://mathoverflow.net/questions/9369/randomness-in-nature/9376#9376 Answer by Steve Huntsman for randomness in nature Steve Huntsman 2009-12-19T16:17:21Z 2009-12-19T16:17:21Z <p>The field of statistical physics exists for this question. Basically when you have a nonequilibrium state that is complicated (e.g., has high entropy, Kolmogorov complexity, or whatever you like) and some kind of hyperbolic dynamics, the process of averaging leads to effective parabolicity. Thus you have things like the heat equation emerging from the effectively deterministic but complex Newtonian (quantum effects really aren't responsible for anything but perhaps the averaging scale, which is extremely small) microdynamics of particle collisions.</p>