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All my questions, answers, and comments on mathoverflow.net are hereby released under the Creative Commons Public Domain Dedication. Please use them freely.
As a matter of courtesy and accuracy, I would request that you make an effort to acknowledge the origin and the authors of any works you use.
2d

reviewed  Close Identify a curve from bunch of numerical data 
2d

reviewed  Close How to find positivedefinite matrices $Q$ and $W$ satisfying $x^T Q x \leq \xi^T W \xi<1$? 
Jun 27 
reviewed  Leave Closed Mathematics equivalent of Feynman's Lectures in Physics? 
Jun 26 
reviewed  Reopen Complex structure on $S^6$ gets published in Journ. Math. Phys 
Jun 26 
revised 
Maximum of the Vandermonde determinant / minimum of the logarithmic energy
replaced new tags with wellestablished ones 
Jun 25 
reviewed  Close heavy subgraph searching result in pseudopatterns in tensor 
Jun 25 
revised 
Logarithmic integral, $π(x)$ and $x/(\ln x)$
replaced tag 'prime' with tag 'primenumbers' 
Jun 25 
reviewed  Leave Open Complex structure on $S^6$ gets published in Journ. Math. Phys 
Jun 24 
reviewed  Close Stationary Phase method with Singular test function 
Jun 24 
comment 
Stationary Phase method with Singular test function
This question was also posted yesterday on Math.StackExchange: math.stackexchange.com/questions/1335958/… 
Jun 23 
reviewed  Reject What are the benefits of viewing a sheaf from the “espace étalé” perspective? 
Jun 22 
reviewed  Close Common density of a random Vector with dependent entries ($Z=(aX,bX)$) 
Jun 22 
revised 
Taylor expansions of Riemannian exponential map and Jacobi fields?
removed deprecated tag 'geometry' 
Jun 21 
revised 
Ambidexterity and Quantization
edited tags 
Jun 20 
comment 
Simply connected CWcomplex with only finitely many nontrivial homotopy and homology groups
Alternatively, fix an odd natural number $n$, and consider the Eilenberg–MacLane space $K(\mathbb{Q},n)$; it has the same homotopy type as $X_n$ above. One can prove that $K(\mathbb{Q},n)$ has reduced homology concentrated in degree $n$ by applying inductively the Serre spectral sequence for the fibre sequences $K(\mathbb{Q},i1) \to \ast \to K(\mathbb{Q},i)$. 
Jun 20 
comment 
Simply connected CWcomplex with only finitely many nontrivial homotopy and homology groups
Consider the rationalization of the $n$sphere, call it $X_n$, defined as the mapping telescope of a sequence of maps $S^n \to S^n \to S^n \to \cdots$ in which the $i$th map has degree $i$. The space $X_n$ has just one nontrivial reduced homology group. Moreover, the homotopy groups of $X_n$ can also be computed knowing that sequential homotopy colimits commute with homotopy groups. It follows that $X_n$ has nontrivial homotopy groups in at most two degrees, $n$ and perhaps $2n1$, which correspond precisely to the homotopy groups of the $n$sphere which are infinite. 
Jun 19 
comment 
Using Magma to Find a Fixed Points Module
Dear @Derek Holt: If you think the question is not suitable, why not just leave a comment instead of an answer? It seems to me that an answer only legitimizes the question. 
Jun 19 
reviewed  Close Using Magma to Find a Fixed Points Module 
Jun 19 
revised 
Open problems/questions in representation theory and around?
replaced inappropriate tag 'openproblem' with tag 'openproblemslist' 
Jun 19 
reviewed  Approve Counterexamples to Kollár's conjecture 