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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.


1d
reviewed Close generate analytically bivariate correlated data
1d
reviewed Close Convergence of the Lyndon - Hochschild - Serre spectral sequence
2d
revised Convex polyhedron and its Gauß-curvature
removed deprecated tag 'geometry'
Jun
29
reviewed Close Identify a curve from bunch of numerical data
Jun
29
reviewed Close How to find positive-definite 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 well-established ones
Jun
25
revised Logarithmic integral, $π(x)$ and $x/(\ln x)$
replaced tag 'prime' with tag 'prime-numbers'
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
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 CW-complex 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 $K(\mathbb{Q},i-1) \to \ast \to K(\mathbb{Q},i)$.
Jun
20
comment Simply connected CW-complex 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 non-trivial 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 non-trivial homotopy groups in at most two degrees, $n$ and perhaps $2n-1$, 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 'open-problem' with tag 'open-problems-list'