# Questions tagged [online-resources]

For questions seeking recommendations for online mathematics resources that are useful at a research level.

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### Tips for reading arXiv papers in mathematics

What tips do you have for reading arXiv papers in mathematics?
This could be too broad if I'm not careful, so here are some limitations on how to make the question appropriate for MO:
I'm interested ...

2
votes

1
answer

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### A more complete set of open problems

Over time, there have been a number of posts on open problems remaining in different fields of math, both here and on the MathSE. So I had the idea of trying to construct a “list of lists” of problems ...

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### A clear map of mathematical approaches to Artificial Intelligence

I have recently become interested in Machine Learning and AI as a student of theoretical physics and mathematics, and have gone through some of the recommended resources dealing with statistical ...

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1
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### Questions on the "generalized" min. singular value of $A$ given $B$: $\min_{L \in \mathbb{R}^{n \times m}} \{\|BL\|_F: \det(A + BL) = 0\}$

Let $A \in \mathbb{R}^{n \times n}$ be a matrix. Recall $\sigma_{\min}(A)$ is the Frobenius distance between $A$ and the set of singular matrices: $$\sigma_\min(A) = \min_{E \in \mathbb{R}^{n \times n}...

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0
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### Questions on the differential of the Lie logarithm

Let $G$ be a Lie group. Recall the Lie logarithm is well-defined about a neighborhood $U \subset G$ of the identity: $\log:U\to \mathfrak{g}$. I am dealing with a research problem that concerns the ...

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### Books/blogs/websites that have open problems in Algebraic geometry

I got admitted in a PhD program in Europe last year. But due to serious mental health issues , I was deemed unfit by the mathematics department to continue the program. I am from a 3rd world nation ...

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0
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### Complete resource of Ngô's course notes on Algebraic Groups and Group Schemes

I'm looking for Ngô's M2 course notes on "Groupes algébriques et schémas en groupes".
The Wayback Machine has an incomplete capture here. However, it apparently lacks chapter 1, 3, and 5.
I ...

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1
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### Is squared geodesic distance a Morse-Bott function on simply-connected Hadamard manifolds?

Let $M$ be a simply connected Hadamard manifold. That is, $M$ is a complete Riemannian manifold with sectional curvature bounded above by 0. Let $f(x,y)=\frac{1}{2}d^2(x,y)$, where $x,y \in M$, and $d(...

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1
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### Where to find hard instances of subsetsum and other famous np-complete problems for testing heuristics against?

[Can move to cs or tcs stackexchange if thats a better home]
I remember back around 2016 DIMACS used to host a list of problem instances of various famous problems in the NP-complete class and harder ...

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6
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### Where can I create nice looking graphics for a paper?

I’m currently writing my first paper, a little paper, and I’d like to have some nice graphics in it. Much of the proof work is tedious analysis and I’d like to give any potential reader visual ...

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### Peterson's quantum cohomology of G/P lectures

Dale Peterson famously gave a series of lectures on the quantum cohomology of flag varieties $G/P$ at MIT in 1997. These lectures are often cited in subsequent papers by other authors on the subject (...

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### How to learn homotopy theory

I studied some basic algebraic topology (homotopy/homology/cohomology groups). When reading about the Dold-Thom theorem, the fancier and more recent sources sooner or later all started to use homotopy ...

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1
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### What is the website address that automatically shows related content instead of pointing to the paper or books [closed]

I was looking for vector bundles online, and I found a website that shows all the related results. By related results, I mean theorems/propositions/definitions, etc. It is not ProjectEuclid, which ...

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### Places where one can post open problems

(This must have been asked before and exist somewhere in Community Wiki, but I can't find it...)
Where can you post open (math) problems? And what are the advantages and disadvantages?
Example: This ...

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0
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### Online encyclopedia of categories?

Being new to categories and mostly interested in specific categories such as the reverse derivative category, I'm wondering if there are any resources like the one for integer sequences and how might ...

2
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1
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### Is there an alternative to the arXiv for uploading mathematical papers?

Is there an alternative to the arXiv for uploading mathematical papers?
Here is the story. Upon attempting to upload a modified version of a published paper to the arXiv, it was put "on hold"...

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9
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### Papers of the masters translated to English in one location

Surely someone has collected these papers and translations and has them in a single location for download? For music there is musipedia. Surely there is a mathepedia equivalent?
If I search gauss ...

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0
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### Mathematical physics roadmap

I am looking for a roadmap to be able to understand more of the physical theory behind mathematical physics (at the level where I can read physics oriented textbooks/monographs)
I have a background in ...

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0
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### Resources for PhD students to guide through the research [duplicate]

I am living in a poor country but I have managed to get admission for a PhD program in Western Europe. This was a daunting task for me due to my family background and also social conditions. ( I don't ...

2
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0
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### Resources where one can find open problems in Analytic Number Theory

Edit: I have asked this question separately because I am in need of some resources which focus on analytic number theory only.So, this question is not a duplicate of:Resources where I can find open ...

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### Resources/Reading Materials on PASA (optimal control theory)

I am currently working on my undergraduate thesis, and my adviser suggested that I look into a Polyhedral Active Set Algorithm (PASA) for my paper. I have been trying to find resources/materials on it ...

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### Resources where I can find open problems in number theory along with their level of difficulty

NOTE: I will not accept an answer because a lot of answers are really good and if anyone want to post under this question later then they are most welcome to post as comment or answer because it will ...

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0
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### Topologically characterizing metrizable spaces

There are some well-known theorems that imply that some metrizable spaces, when satisfying other topological properties, are unique up to homeomorphism. Here are a few examples, where "perfect&...

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### IOPsciences and a missing reference

My university has a subscription at IOPSciences
I am interesting in this article: Galochkin A.I. (1984): On estimates, unimprovable with respect to height, of some linear forms. Mat. Sb. 124 (166), ...

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### How do you generate math figures for academic papers?

Good day! I am looking for any tool that would allow me to generate a figure similar to the figures embedded in the paper by King et al. (2020) titled "Trigonometry: a brief conversation."
...

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0
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### Where to upload digitized LaTeX versions of old papers?

Let's say I took the time to convert into proper modern LaTeX a few old math papers (which cannot be found online, or only in poorly scanned versions which are hard to read due to this). If someone ...

2
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0
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### Ultra math search engine [duplicate]

Does anyone know searching engine for arxiv.org math formulas?
Like https://www.searchonmath.com and https://approach0.xyz/search/
In my opinion, we should have a search engine that can find formulas ...

6
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2
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### Resource request on "$\in$-homomorphisms" in Set Theory

Very loosely put, this is the intuitive idea behind an $\in$-homomorphism:
Let $\mathcal{U}$ and $\mathcal{W}$ be universes of sets. A function $f \colon \mathcal{U} \to \mathcal{W}$ is said to be an $...

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### sci.math.research archive?

Does there exist an archive somewhere of posts to the USENET newsgroup sci.math.research?
The best approximation I'm aware of is Google Groups. However, despite ...

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2
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### Are old issues of math journals from Belarus Academy of Sciences available online?

I am interested in some papers in Russian which have appeared in the journals "Doklady Akademii Nauk BSSR" and "Vestsi Akademii Navuk BSSR". Are scanned copies available? I could ...

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### Great graduate courses that went online recently

In 09.2020 by pure chance I discovered the YouTube channel of Richard Borcherds where he gives graduate courses in Group Theory, Algebraic Geometry, Schemes, Commutative Algebra, Galois Theory, Lie ...

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0
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### Social media for a mathematics related idea buckets

Are there any good social media platforms that can recommended for communicating ideas related to mathematics?
The reason for asking is that I am in the situation that, albeit having studied math, I ...

4
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0
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### How to put a monetary incentive on an open research problem? [closed]

Since the old days, many famous mathematicians have been attaching monetary rewards to problems. I would like to put monetary bounties on some research mathematics problems. Some of those problems ...

1
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1
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### Can any one suggest a very basic book for fuzzy graph theory?

Can anyone help with a very basic book on fuzzy graph theory for a beginner to it with good explanations.
Any video course online on fuzzy graph theory extensively to help understand please share link....

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0
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### Online courses for mathematics [closed]

I'm sorry if I'm posting this in the wrong forum. My background is in biology and medicine. I am looking to re-learn undergraduate-level mathematics, in particular discrete mathematics, calculus, and ...

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3
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### Wiki for consequences of axiom of choice?

I raised the following question as part of another MO question, but I am following the suggestion of Nate Eldredge to make it a question in its own right.
For many years, there has a been a valuable ...

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2
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### Wayback Machine for mathematics?

I have had a couple of experiences recently which have made me wonder whether the mathematics community should try to establish and maintain something like the Wayback Machine, but specifically ...

2
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1
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### Recommendation for books on boundary-value problems that include perturbed boundaries and many solved problems

I am looking for a book or resource that contains applied math analytical methods and a lot of solved problems in Boundary-Value Problems for second-order PDEs, and if it could be related to wave-...

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0
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### Is the DispersiveWiki website down?

Somewhat recently I learned about a website called the DispersiveWiki which is/was maintained by James Colliander. I have found a few different links to the website from around the web (e.g. http://...

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### Online study groups for individual mathematical texts

This has been one of my earlier academic dreams. I have pitched the idea to Prof Ravi Vakil, among others. Recently, because of participation in the mathematical competition hosted by Alibaba, I have ...

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0
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### Solution of the Mason-Weaver equation in cylindrical coordinates

I'd like to know if there is some litterature about the cylindrical Mason-Weaver equation.
The basic Mason-Weaver equation is treated in Wikipedia :
$$\partial_t f(t,x)=\partial_x f(t,x)+\partial_{...

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6
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### Online events during the quarantine

With many places on earth subjected to quarantine and large gathering prohibited, there are announcements of online seminars and talks open to people around the world. The talks can be conducted via ...

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### Atlas-like websites on specific areas of mathematics

In this post, we look for the existing atlas-like websites providing well-presented classifications or database about some specific areas of mathematics. Here are some examples:
GroupNames: https://...

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### Have the "Bayreuther Mathematische Schriften" ever been digitalized?

See update below.
This is borderline off-topic (certainly not a research question), but the rather successful story of a similar question gives me hope.
The Bayreuther Mathematische Schriften were a ...

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### Is there a connection between representation theory and PDEs?

As a PhD student, if I want to do something algebraic / linear-algebraic such as representation theory as well as do PDEs, in both the theoretical and numerical aspects of PDEs, would this combination ...

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### Videos of Gian-Carlo Rota lectures

I apologize if this is off topic.
I think most of his listeners would agree with me that Gian-Carlo Rota had a wonderful style of lecture delivery. I have heard him lecture, both as an undergraduate ...

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### What has happened with the Publications of the $n$Lab?

What has happened with the Publications of the $n$Lab? They seem to have published only a couple of articles back in 2011, 2012. A little search i made was not very enlightening.
Has the project ...

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### Mirror site for the NIST Digital Library of Mathematical Functions (DLMF)

For research I use the NIST Digital Library of Mathematical Functions (https://dlmf.nist.gov/) quite often for looking up basic facts about special functions. At the moment, however, this gives
...

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### Polymath type websites for specialized areas

This question is inspired by the success and more importantly, the democratizing affect of the polymath projects and Mathoverflow. I put the idea in my NSF proposals a few times, but the panels don't ...

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### Eigenvectors of sum of SO(3) matrices

I asked this question before on MSE but go no answers. It seems that the problem is rather difficult so I thought of trying here. Given two matrices $A,B\in SO(n)$, each describing a rotation by ...