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-4 votes
0 answers
90 views

German to English translation of mathematical text [closed]

I am trying to read Jarvik's famous 1929 article in German on calculating Hausdorff dimensions of certain sets. Where can I get it translated to speed up things?
user561883's user avatar
-1 votes
0 answers
37 views

Sets minimizing a ratio of Gaussian integrals

Fix $p \in (0,1]$ and $\tau > 0$. Let $\mathcal S_p$ be the colleciton of Borell subsets of $\mathbb R$ of Gaussian measure $p$, and veryfing $-S=S$. Define the following functionals on $\mathcal ...
dohmatob's user avatar
  • 6,969
14 votes
3 answers
2k views

Where did this theorem appear?

In a 1934 paper of Erdős and Turán , whose title is On a problem in the elementary theory of numbers, they said, … Their proof depends on a theorem of Mr. Pólya asserting that if we denote by $q_1<...
Tong Lingling's user avatar
6 votes
2 answers
266 views

Existence of collision-free assignment of points

Let $P = \{P_1, \ldots, P_N\}$ and $Q = \{Q_1, \ldots, Q_N\}$ be two sets of $N$ distinct points in $\mathbb{R}^n$. Each point in $P$ is to be assigned to a unique point in $Q$ and move toward it ...
Mark Ren's user avatar
3 votes
1 answer
292 views

On the connection between chaos and ergodicity

This is a specific question pertaining to the 'universal' properties of chaos in dynamical systems. Consider a continuous map $T:B\to B$, with $B\subset\mathbb{R}^n$ a compact subset. This defines a ...
vmist's user avatar
  • 1,131
2 votes
1 answer
166 views

An equality for the arithmetic genus of a divisor on a smooth surface

Let us work over the field of complex numbers for simplicity, although many things are probably true in general. Let $C$ be a projective scheme of dimension $1$. The arithmetic genus of $C$ is usually ...
Jérémy Blanc's user avatar
-4 votes
0 answers
98 views

How many aleph fixed points there are? [closed]

Recently I've learned the concept of aleph-fixed point. I am wondering how many fixed points there are. More specifically, what is the size of $\{\beta <\kappa\mid \beta=\aleph_\beta\}$. ...
yiqi jin's user avatar
0 votes
0 answers
57 views

On the expected quality of a rank-$1$ approximation of a complex Gaussian noise covariance matrix

I am developing quality coefficients for a specific type of approximation of covariance matrices. I want to to specify meaningful lower bounds (or rather thresholds), for which I would like to use the ...
mgns's user avatar
  • 101
-1 votes
0 answers
39 views

Hereditary and Cumulative Hierarchy [migrated]

I’ve been told that it is a well-known fact that for an inaccessible cardinal $\kappa$, we have $H_\kappa=V_\kappa$ where $H_\kappa$ is defined as $\{x:|\mathrm{TC}(x)| <\kappa\}$. But I can not ...
yiqi jin's user avatar
-1 votes
1 answer
98 views

Multitude centroids of hexagons are collinear

Using a computer, I found the following result. Now, I'm looking for a solution to prove this result: Let $A_{01}$, $A_{02}$, $A_{03}$, $A_{04}$, $A_{05}$, $A_{06}$ be six points in the plane, such ...
Đào Thanh Oai's user avatar
8 votes
0 answers
221 views

Ind extension of Stone duality is fully faithful

$\DeclareMathOperator\Pro{Pro}\newcommand\Fin{\mathrm{Fin}}\newcommand\Top{\mathrm{Top}}\DeclareMathOperator\Ind{Ind}\DeclareMathOperator\colim{colim}$By Stone duality, the natural map $$\Pro(\Fin)\to ...
user14411's user avatar
  • 305
2 votes
0 answers
76 views

On the integral closure of $\mathbb{Z}_p$ over a $p$-adic cyclotomic field [duplicate]

Notation. Let $p$ be a prime. Let $\mathbb{Q}_p$ be the $p$-adic number field and let $\mathbb{Z}_p$ be the ring of $p$-adic integers. For any positive integer $n\ge2$, let $\zeta_n\in\mathbb{Q}_p^{{\...
Fresh man 's user avatar
4 votes
2 answers
354 views

Finite pushforward of symmetric differentials

Let us consider a finite surjective morphism $f\colon X\to Y$ between smooth projective varieties. As we know, for each $r\leq\dim(X)=\dim(Y)$, there is an injection $f^*\colon \Omega_Y^{r}\to f_*\...
Joshua-ooo's user avatar
1 vote
0 answers
112 views

Etale fundamental group of modular curve

What is the étale-$\pi_1$ of the modular curve $Y$ with level structure $\Gamma \subset \operatorname{PSL}(2,\mathbb{Z})$? How is that related to $\Gamma$? I have found some related discussions about ...
Michael Cheng's user avatar
1 vote
0 answers
62 views

Does taking a weighted average of points in toroidal space always produce a unique answer?

Let's say that we have a bunch of points in toroidal space meaning for our N dimensions there's a value between 0 and 1 and that it wraps around between them and distance is the L2 norm. Let's further ...
Bram Cohen's user avatar

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