most recent 30 from http://mathoverflow.net 2013-05-23T00:22:12Z http://mathoverflow.net/feeds/user/11575 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/44326/most-memorable-titles/49469#49469 none 2010-12-15T00:52:11Z 2012-01-01T05:43:37Z

<p>There's an algebra book called "Rings and Ideals". I thought of a subtitle: "Marriage during the Revolution".</p> <p>I remember reading Jacobson's "Basic Algebra I" on the bus on the way to university, and someone noticing it and thinking it was a high-school level text.</p> <p>Similarly, Serre(?) has a difficult book about number theory, titled simply "Arithmetic".</p>

http://mathoverflow.net/questions/49151/most-intricate-and-most-beautiful-structures-in-mathematics/49468#49468 none 2010-12-15T00:41:46Z 2011-03-26T11:12:03Z

<p>Another one: <a href="http://en.wikipedia.org/wiki/Chaitin%27s_constant" rel="nofollow">Chaitin's Omega constant</a>.</p> <p>Original answer by: <strong><a href="http://mathoverflow.net/users/11575/none" rel="nofollow">none</a></strong></p>

http://mathoverflow.net/questions/49151/most-intricate-and-most-beautiful-structures-in-mathematics/49467#49467 none 2010-12-15T00:37:59Z 2010-12-15T00:37:59Z

<p>What about the complex numbers, from the way all the theorems of complex analysis fit together so well.</p> <p>Also: NGB set theory (I mean the formal object Th NBG, not the general informal topic): finitely axiomatizable through an intricate argument, and proves just about everything in mathematics.</p>

http://mathoverflow.net/questions/49363/cheap-non-constructive-free-group-generating-rotations-for-banach-tarski/49465#49465 none 2010-12-15T00:34:31Z 2010-12-15T00:34:31Z

<p>I thought the exposition in the Wikipedia article was pretty good-- not hard to follow even without knowing much set theory.</p>

http://mathoverflow.net/questions/49437/why-are-so-few-operations-with-arity-bigger-than-2/49464#49464 none 2010-12-15T00:33:18Z 2010-12-15T00:33:18Z

<p>I'd have thought it was just notational. When the arity is > 2, we usually end up coding the operands into a vector or tensor or whatever. The determinant mentioned above is an obvious example of that: a unary operation on a matrix, or a tensor acting on n vectors, depending on how we look at it.</p>