most recent 30 from http://mathoverflow.net 2013-05-24T08:04:25Z http://mathoverflow.net/feeds/user/1997 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/111838/degree-of-a-generically-finite-map Ongaro Nyang' 2012-11-08T17:54:15Z 2012-11-09T19:13:03Z

<p>I have a rational map $f:\mathbb C^n\longrightarrow \mathbb C^n,$ all I know $f$ is defined by homogenious polynomials of degree $m$ and $f$ not necessarily a morphism. Computer packages aside, I am wondering if the passonate algebraic geometers have a general scheme of computing $\deg f$ explicitly?</p>

http://mathoverflow.net/questions/106608/hurwitz-numbers-and-hurwitz-theory Ongaro Nyang' 2012-09-07T14:58:21Z 2012-11-08T17:56:16Z

<p>Am currently doing a self-study of hurwitz numbers and Hurwitz theory, is there a good source for one with only basic knowledge of algebraic geometry. Notes and papers are also welcome.</p>

http://mathoverflow.net/questions/78037/video-lectures-for-algebraic-geometry/79024#79024 Ongaro Nyang' 2011-10-24T20:57:01Z 2011-10-25T12:43:08Z

<p>David Ben-Zvi’s lectures on representation theory and topological field theory:</p> <p><a href="http://online.kitp.ucsb.edu/online/langlands_m08/" rel="nofollow">http://online.kitp.ucsb.edu/online/langlands_m08/</a>. On the same line see the seminar lectures by John Baez and James Dolan <a href="http://math.ucr.edu/home/baez/qg-fall2007/" rel="nofollow">http://math.ucr.edu/home/baez/qg-fall2007/</a></p>

http://mathoverflow.net/questions/78060/means-of-promoting-mathematics-in-young-countries Ongaro Nyang' 2011-10-13T20:42:34Z 2011-10-22T02:01:43Z

<p>We all know mathematics is life, this question is for Mankind. It's mathoverflow here when some parts of the world we have mathunderflow! I think we can do something through ideas. A similar question "Good ways to engage in mathematics outreach" has been featured but this is a different question all together.</p> <p>In this question, am interested in understanding what the so called super countries in mathematics done right utilizing the little resources they have in the promotion(development) of mathematics. How can very young country (mathematics development is wanting, the research output is low, some fundamental courses are not even taught at the first place due to lack of resource persons) move on? What are some of the ideas which have helped countries with a small economy grow? Are there mathematicians who have been involved in development of mathematics in developing/ less developed countries which are experiencing an upward trend? How did you do it?</p>

http://mathoverflow.net/questions/77616/d-modules-and-algebraic-solutions-of-pdes Ongaro Nyang' 2011-10-09T17:51:27Z 2011-10-10T06:59:23Z

<p>I am not certain if this is a complete question and I fear it might be shot down. Anyway, I try to pose it. My question is in connection to using D-modules to study PDEs (and systems of PDEs). When I was doing a perusal on "A primer of algebraic D-modules by S. C. Coutinho" the justification on the importance of D-modules; they provide an algebraic tool towards the solution of differential equations. This is the story I always hear! Do someone have a reference or more information about D-modules and algebraically solution of PDEs ?. </p>

http://mathoverflow.net/questions/111838/degree-of-a-generically-finite-map Ongaro Nyang' 2012-11-09T12:13:05Z 2012-11-09T12:13:05Z

I have checked finiteness genericall by calculating the inverse image at a point.

http://mathoverflow.net/questions/111838/degree-of-a-generically-finite-map Ongaro Nyang' 2012-11-09T10:52:52Z 2012-11-09T10:52:52Z

@Daniel,that was just an example to answer &quot;defined by polynomials&quot;. To me such a map is a morphism if the polynomials have no common root and I get an induced map $\mathbb P^{n−1}\longrightarrow \mathbb P^{n−1}$.

http://mathoverflow.net/questions/106608/hurwitz-numbers-and-hurwitz-theory Ongaro Nyang' 2012-11-09T07:59:39Z 2012-11-09T07:59:39Z

@Janas thanks for suggestion seems fruitful, I wrote him a email, he is shared the notes on <a href="http://www-fourier.ujf-grenoble.fr/Course-notes,1097.html?lang=fr" rel="nofollow">www-fourier.ujf-grenoble.fr/&hellip;</a>

http://mathoverflow.net/questions/111838/degree-of-a-generically-finite-map Ongaro Nyang' 2012-11-09T07:55:20Z 2012-11-09T07:55:20Z

Example $n=3,$ $f$ consinder something like $(a,b,c)\longmapsto(ab-2c^2,7ac, c^2+8ab).$

http://mathoverflow.net/questions/111838/degree-of-a-generically-finite-map Ongaro Nyang' 2012-11-08T22:23:52Z 2012-11-08T22:23:52Z

@Felipe for $\ker f\neq 0$ I only wanted to say $f$ is not a morphism, fixed it now.

http://mathoverflow.net/questions/111838/degree-of-a-generically-finite-map Ongaro Nyang' 2012-11-08T22:06:05Z 2012-11-08T22:06:05Z

@ Felipe it seems like that is true if $f$ is a morphism never true in general.

http://mathoverflow.net/questions/88073/the-fundamental-theorem-of-galois-theory/88080#88080 Ongaro Nyang' 2012-02-10T11:29:13Z 2012-02-10T11:29:13Z

-Yes, but there were many proofs earlier(and modern) for the fundamental theorem of Galois theory before Emil's. Emil's proof is simpler than the proof the usual ones we find in every mongraph

http://mathoverflow.net/questions/23478/examples-of-common-false-beliefs-in-mathematics/73123#73123 Ongaro Nyang' 2011-10-19T18:57:41Z 2011-10-19T18:57:41Z

@Robert of course I meant, the use of trying to use the fact $\sqrt{xy}=\sqrt{x}\sqrt{y}$ for all real numbers

http://mathoverflow.net/questions/78060/means-of-promoting-mathematics-in-young-countries/78231#78231 Ongaro Nyang' 2011-10-16T09:22:36Z 2011-10-16T09:22:36Z

Dear Gil, am lost of words!

http://mathoverflow.net/questions/77616/d-modules-and-algebraic-solutions-of-pdes/77668#77668 Ongaro Nyang' 2011-10-15T05:11:45Z 2011-10-15T05:11:45Z

Nice paper indeed

http://mathoverflow.net/questions/78060/means-of-promoting-mathematics-in-young-countries/78084#78084 Ongaro Nyang' 2011-10-14T07:10:22Z 2011-10-14T07:10:22Z

wonderful ideas here!

http://mathoverflow.net/questions/78060/means-of-promoting-mathematics-in-young-countries/78070#78070 Ongaro Nyang' 2011-10-14T07:08:09Z 2011-10-14T07:08:09Z

Thanks this reflects what I am seeking

http://mathoverflow.net/questions/77616/d-modules-and-algebraic-solutions-of-pdes Ongaro Nyang' 2011-10-10T14:47:30Z 2011-10-10T14:47:30Z

Algori yes, however, am very much interested in the algebraic ones! Ketil, true! this are the stories we always here that D-modules are geared towards providing an algebraic study to systems of PDEs do someone know people(research group) studying them using algebraic D-modules. I will be glad to know