most recent 30 from http://mathoverflow.net 2013-06-19T18:13:32Z http://mathoverflow.net/feeds/user/11500 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/77934/are-quivers-useful-outside-of-representation-theory/122694#122694 isomorphismes 2013-02-23T04:25:08Z 2013-02-27T04:55:00Z

<p>Speaking of industrial applications, graph theory is quite popular among computer people. For example Facebook's <code>EdgeRank</code> determines who sees what in the news feed. And <code>neo4j</code> is a popular (or at least well-advertised) graph database, with <code>gremlin</code> a graph-traversal language. LinkedIn has a team devoted to "social network analysis" and graphs are hot as well in "complexity theory" including models of the brain. For example <a href="http://video.neo4j.org/RHqy/the-pathology-of-graph-databases-by-marko-a-rodriguez/" rel="nofollow">http://video.neo4j.org/RHqy/the-pathology-of-graph-databases-by-marko-a-rodriguez/</a> gave me a flavour of how the web-programming crowd sees graphs.</p> <p>I don't know if any of the above interests you but at least outside of pure mathematics I believe quivers-as-directed-graphs have practical applications.</p>

http://mathoverflow.net/questions/3997/are-there-any-interesting-connections-between-game-theory-and-algebraic-topology/121627#121627 isomorphismes 2013-02-12T17:42:52Z 2013-02-12T17:42:52Z

<p>I'm coming from the other side: familiar with game theory and learning about algebraic topology.</p> <ul> <li>I know Kakutani's fixed point theorem was used to simplify <a href="http://web.mit.edu/linguistics/events/iap07/Nash-Eqm.pdf" rel="nofollow">Nash's seminal paper</a>.</li> <li>If you think about a simple normal-form game like Prisoner's Dilemma or Coordination Game, <img src="http://epress.anu.edu.au/cs/chap5Newth-final-10.jpg" alt="prisoner's dilemma"> the arrows between the payoff matrix are governed by $>_A$ and $>_B$ meaning the ordering of payoffs by players A and B. I know topological spaces aren't necessarily orderable, but this seems topological in flavour since distance doesn't matter. (Whether you lose £3 or get your head chopped off, I don't care as long as it doesn't affect me.) I think of this as like a "topological gravity" creating the Nash equilibria.</li> </ul>

http://mathoverflow.net/questions/104649/staggered-timing-on-2-d-random-walks-by-multiple-agents isomorphismes 2012-08-13T22:11:37Z 2012-08-28T00:22:00Z

<p>In 2-D lattice random walks by multiple drunks who can't step onto each other, mathematically I would just say the whole cellular automaton updates "at once".</p> <p>But to simulate this on a computer, I need to perform computations in some order. This presents obvious complications.</p> <p>Can anyone point me in the right direction with Google or the research literature? I'm sure I'm not the first person to stumble across this issue, but I don't know what vocabulary others have used to talk about it.</p>

http://mathoverflow.net/questions/14133/is-there-a-category-of-non-well-founded-sets/100200#100200 isomorphismes 2012-06-21T03:06:19Z 2012-06-21T03:06:19Z

<p>According to this doctoral thesis <a href="http://www.andrew.cmu.edu/~awodey/students/hughes.pdf" rel="nofollow">http://www.andrew.cmu.edu/~awodey/students/hughes.pdf</a> by Jesse Hughes (supervised by Steve Awodey), cogebras = coalgebras are the appropriate category to study non-wellfounded sets.</p>

http://mathoverflow.net/questions/8846/proofs-without-words/76951#76951 isomorphismes 2011-10-01T23:31:18Z 2011-10-01T23:31:18Z

<p>From Wikipedia: here is a "proof without words" of the Yoneda Lemma.</p> <p><img src="http://upload.wikimedia.org/wikipedia/commons/b/b1/YonedaLemma-02.png" alt="alt text"></p>

http://mathoverflow.net/questions/31879/are-there-other-nice-math-books-close-to-the-style-of-tristan-needham/65726#65726 isomorphismes 2011-05-22T18:49:13Z 2011-05-22T18:49:13Z

<p>Roger Penrose's <em>The Road to Reality</em>. Needham says in VCA that Penrose taught him what good style is.</p>

http://mathoverflow.net/questions/14518/applications-of-noncommutative-geometry isomorphismes 2013-03-19T07:15:59Z 2013-03-19T07:15:59Z

Charles, I'm not an expert on NCG but it seems to me that most of the phase spaces in the real world are NONcommutative. You drink after pouring into the cup, marry after dating (or at least the order tells us the culture!), put the car in drive before pressing the gas, and so on. Euclidean distance seems a special case in this regard.

http://mathoverflow.net/questions/53446/extension-of-eulers-method-using-higher-taylor-polynomials isomorphismes 2011-01-27T07:13:11Z 2011-01-27T07:13:11Z

Thanks. Sorry, I didn't mean to ask a trivial question.

http://mathoverflow.net/questions/19046/open-source-mathematical-software/49903#49903 isomorphismes 2010-12-20T07:00:23Z 2010-12-20T07:00:23Z

I can't comment!