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bio website math.temple.edu/~rivin
location USA
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visits member for 4 years, 8 months
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Professor of Mathematics at Temple University. Regius Professor of Mathematics at St Andrews starting Fall 2015.


10h
answered Solving over-determined system of polynomials
11h
comment Computing the Galois group of a polynomial
I believe this algorithm is the one described by Susan Landau in the early '80s (and it has pretty bad complexity).
17h
answered How to determine whether the following sum is nonzero for a given multivariate polynomial?
17h
comment How to determine whether the following sum is nonzero for a given multivariate polynomial?
What consitutes an "algebraic method"?
23h
comment Guessing degrees
And do you mean "subpolynomial" time? Then the answer is obviously no, since it takes linear time ($c=1$) to just read the polynomial.
23h
comment Guessing degrees
I don't understand the question. What do you mean by "guess"? And what do you mean by faster? (what class of algorithms are you allowing - deterministic? probabilistic? If yes to probabilistic, then what kind?
2d
comment Integral points on a particular family of curves
That's a nice idea, and the computation you mention give a boost to the idea that there is a high likelihood of only trivial solutions.
Jul
31
answered Sampling from random unimodular matrices of a particular type?
Jul
31
comment A generously vertex transitive graph which is not Cayley?
Most of the examples are not Cayley - check them out.
Jul
31
answered A generously vertex transitive graph which is not Cayley?
Jul
31
comment Are most random variables trivially sub-gaussian?
It is an idealization - for practical purposes, the truncated version is no less useful...
Jul
31
answered SO$(4)$ (& SO$(n)$) characterization?
Jul
30
revised Analysis of the Laplacian of a random bipartite graph
fixed typo
Jul
30
answered Are most random variables trivially sub-gaussian?
Jul
30
answered Analysis of the Laplacian of a random bipartite graph
Jul
29
comment Counting elements with certain word length in abelian groups
Just a remark: this is not trivial even for cyclic groups.
Jul
29
comment Is there a way to find an efficient set of relations for presenting the subgroup generated by two matrices in $SL(2, q)$?
Is there any complexity bound for this?
Jul
29
comment Is there a way to find an efficient set of relations for presenting the subgroup generated by two matrices in $SL(2, q)$?
Two random matrices will generate the whole group, with high probability (which becomes higher as $q$ grows). There are certainly known presentations of the whole of $SL_2(q),$ basically due to Steinberg, as the OP says.
Jul
28
answered How do powers affect asymptotics in generating functions?
Jul
27
answered What are the 2-generated subgroups of the special linear group $SL(2, q)$ over a finite field?