# All Questions

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### I discovered something, what do I do?

I've recently made a mathematical discovery and being still in high school I have no idea how to publish my discovery or who to tell. I told my teachers but that got me nowhere.
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### convex optimization

Attached below is a convex problem. I just start learning this and is kind of confused of this question. I notice that the dom of W is convex, tr(WQ) is convex, the composition of convex functions ...
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### Coming up with a function or a single graph, given its characteristics (pre-calculus) [on hold]

Give an example of a function or a single graph which has the following characteristics: (a) Hole at (3,-1). ...
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### Conditions for existence of Penrose diagrams

A Penrose diagram (also known as a conformal diagram or Carter-Penrose diagram) is a technique for visualizing the causal (light-cone) structure of a 3+1-dimensional manifold. Usually the diagram is ...
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### Resource needed on Lerch's transcendent

I am looking for resources in english which discuss basic properties of the Lerch's transcendent function. The Lerch Transcendant is defined by: ...
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### Generating (or availability of) large strongly regular graphs

Are there collections of already generated large strongly regular graphs available to download? By large I mean $n >= 200$ where $n$ is the number of vertices. I found Ted Spence's page on srgs, ...
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### Curvature of a finite metric space

I am sorry to ask a very vague question, but: What are good ways to define the curvature of a finite metric space? The best way I can think of is: the curvature of a finite metric space $M$ is ...
579 views

### Can I find Fermat's complete works anywhere?

I admire the mathematician very much and want to look at his writings. Is there anywhere in book or web form that has a collection of his writings?
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### Chern classes of ideal sheaf of locally complete intersection

Let $C\varsubsetneq X$ be a reducible locally complete intersection closed pure $1$-dimensional subscheme in a smooth projective variety of dimension $3$ over a algebraically closed field $k$ of ...
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### Quantification of the extent of periodicity in a time series using fractal analyses

Suppose I have a time series which is almost periodic. If I were to segment each of the visually most evident periods i.e. say of the longest period, I would find a strong mean cross-correlation among ...
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### Eigenvalues of a random matrix [on hold]

For test cases i generated a random real uniform distributed matrix with entries from the intervall $[0,1]$. Here is the MATLAB Code i used ...
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### cohomology ring of base-point-preserving maps on the 3-sphere

I find that $\text{Map}_*(S^3;S^3)=\Omega^3S^3$. I want to find the cohomology ring of $H^*(\Omega^3S^3;\mathbb{Z}_2)$. In the paper On configuration spaces, their homology, and Lie groups, I find ...
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### How “small” can an ordinal be made by forcing?

I know that forcing essentially does not change the ordinals, but by small I mean in comparison with other ordinals whose definition might not be stable under forcing, like the smallest uncountable ...
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### eigenvalues of cycle and its complement [on hold]

I am trying to find the eigenvalue of cycle graph and its complement. How to simplify.Suppose $\omega^{1}+\omega^{n-1}=2cos (2\pi/n)$, then, $\omega^{\frac{n-1}{2}}+\omega^{\frac{n+1}{2}}=?$ Is it ...
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### indecomposable decomposition for a commutative ring

Let $R$ be a commutative ring with identity. We say that $R$ has an indecomposible decomposition if it can be wrighten as a finite direct sum of indecomposiable rings. Is there any characterization ...
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### Can such categorical notion of action be formalized?

I'm wondering if it's possible to find an universal construction for a general concept of action for (single-sorted?) finite product sketches, such that one of those is "acting" on the second in the ...
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### Example of measure of non-compactness

I can't understand the following example of measure of non-compactness, which was given in this article. Definition: A non-negative function $\phi$ defined on the bounded subsets of $X$ will be ...
420 views

### Category theory for Algebraic Geometry

How much of category theory should I know to view schemes, sheaves and cohomology concepts as concrete cases of abstract categorical concepts? Is there a textbook of category theory for AG people?
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### bar construction and loop space cohomology

Let $X$ be a topological space. Then its chain complex $C_{*}(X)$ is naturally a coalgebra (as explained here Does homology have a coproduct?). In particular if $X$ is simply connected we have that ...
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