User josiah sugarman - MathOverflowmost recent 30 from http://mathoverflow.net2013-06-20T02:33:40Zhttp://mathoverflow.net/feeds/user/2224http://www.creativecommons.org/licenses/by-nc/2.5/rdfhttp://mathoverflow.net/questions/7782/are-the-inner-automorphisms-the-only-ones-that-extend-to-every-overgroupAre the inner automorphisms the only ones that extend to every overgroup?Josiah Sugarman2009-12-04T16:22:59Z2010-01-07T00:01:19Z
<p>Let H be a group. Can we find an automorphism $\phi :H\rightarrow H$ which is not an inner automorphism, so that given any inclusion of groups $i:H\rightarrow G$ there is an automorphism $\Phi: G\rightarrow G$ that extends $\phi$, i.e. $\Phi\circ i=i\circ \phi$?</p>
http://mathoverflow.net/questions/8445/learning-topology/8456#8456Answer by Josiah Sugarman for Learning TopologyJosiah Sugarman2009-12-10T14:21:34Z2009-12-12T08:06:49Z<p>For General Topology I recommend Kelley's book.</p>
<p>I learned general topology with a book that only contained theorems and I referred to Kelley when I had too much difficulty proving them. This method of learning works very well with General topology since most of the proofs are straight forward.</p>
http://mathoverflow.net/questions/3559/colloquial-catchy-statements-encoding-serious-mathematics/3618#3618Comment by Josiah SugarmanJosiah Sugarman2009-12-10T15:59:23Z2009-12-10T15:59:23ZYou need Banach's fixed point for the uniqueness, but the existence follows Brouwer's fixed point.http://mathoverflow.net/questions/8445/learning-topology/8452#8452Comment by Josiah SugarmanJosiah Sugarman2009-12-10T14:12:57Z2009-12-10T14:12:57ZI love Hatcher's book. It's very easy to read. Honestly, I've never read it through and I only use it as a reference.http://mathoverflow.net/questions/8257/mathematical-definition-of-runningComment by Josiah SugarmanJosiah Sugarman2009-12-09T02:20:12Z2009-12-09T02:20:12Z@Alberto
I don't like the fact that someone systematically downvoted fpqc's answers and questions. His questions and answers are generally good. Up and Down voting is important and should not be a petty vengeful act. fpqc is not nice, but all the downvoting he does is intended to make the site better. And the majority (though not VAST majority) of his downvotes, including the one toward one of my answers, appears to be correct.http://mathoverflow.net/questions/7983/does-this-inequality-hold/8000#8000Comment by Josiah SugarmanJosiah Sugarman2009-12-07T00:32:06Z2009-12-07T00:32:06ZI'm gonna delete my answer before my Rep. goes down any further add simultaneously win the first peer pressure badge.http://mathoverflow.net/questions/7983/does-this-inequality-hold/7991#7991Comment by Josiah SugarmanJosiah Sugarman2009-12-06T13:02:50Z2009-12-06T13:02:50ZSorry about that, I knew it was morally wrong while I was doing it and couldn't help myself.