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Prerequisites for Lie groups and Lie algebras

lie-groups lie-algebras

asked 1 min ago user239557 1

6

votes

1

answer

35

views

Size of an “average” $\epsilon$-net on the unit sphere

probability combinatorics geometry expected-value upper-lower-bounds

answered 1 min ago Ross Millikan 354k

1

vote

1

answer

45

views

Nakayama's lemma corollary

abstract-algebra commutative-algebra

modified 2 mins ago Maulik 164

0

votes

1

answer

29

views

Turbulent modelling and the reynold stress term

numerical-methods physics fluid-dynamics computational-science

answered 3 mins ago Tanmay Agrawal 115

2

votes

1

answer

2k

views

Explanations about the volume of a regular simplex

volume simplex

modified 4 mins ago Community♦ 1

0

votes

1

answer

63

views

Prove that there is no continuous bijection $f:\mathbb Q\to K$ of $\mathbb Q$ on a compact metric space $K$.

analysis

answered 5 mins ago Balaji sb 595

0

votes

0

answers

6

views

Can you give me a hint to solve $ \int_{0}^{\infty} xe^{-cx^{2}} sin(tx) dx$

real-analysis calculus

asked 5 mins ago DougL 53

0

votes

0

answers

4

views

Evaluating $\zeta(-2n,\sqrt{a_1};\sqrt{a_1},\sqrt{a_2})$

number-theory analytic-number-theory zeta-functions

modified 6 mins ago BookWick 399

3

votes

1

answer

27

views

Maximum number of triples from $[n]$ so that no two elements appear together more than once

combinatorics elementary-set-theory extremal-combinatorics

answered 7 mins ago bof 65.7k

1

vote

1

answer

18

views

Find the unique solution to the IVP $x' = Ax$ where $A = \begin{bmatrix} {-3}&{2} \\ {-1}&{-1}\end{bmatrix}$

ordinary-differential-equations matrix-equations initial-value-problems

answered 9 mins ago Moo 8,486

-1

votes

0

answers

56

views

Can we find a curve from one coordinated data?

linear-algebra soft-question manifolds curvature

modified 9 mins ago Creator 2,777

2

votes

1

answer

30

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Proof verification: Convexity and second derivative

real-analysis solution-verification convex-analysis

answered 11 mins ago Siong Thye Goh 133k

1

vote

1

answer

26

views

Union of Sets Definition

set-theory

modified 12 mins ago jstl 103

0

votes

0

answers

18

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Integration in cylindrical coordinate system

integration partial-differential-equations fluid-dynamics cylindrical-coordinates boundary-layer

modified 13 mins ago Tanmay Agrawal 115

-1

votes

0

answers

13

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Prove that two surfaces attached to the same boundary have same boundary in the plane of the parameter coordinates

differential-geometry parametrization

modified 13 mins ago Buraian 4,766

1

vote

0

answers

27

views

Find and solve a recurrence relation

discrete-mathematics recurrence-relations

modified 16 mins ago Gabriela 231

0

votes

2

answers

33

views

What is the group structure of $U_n=1+p^n\mathbb Z_p$?

abstract-algebra

answered 17 mins ago Balaji sb 595

0

votes

0

answers

7

views

Data Management - Combinations

combinatorics combinations

asked 18 mins ago Koushik Paul 1

0

votes

1

answer

15

views

Is $(\mathbb{N}, \tau)$ homeomorphic to $(\mathbb{N} \times \mathbb{N}, \tau')$?

general-topology

modified 21 mins ago Alejandra Benítez 326

0

votes

0

answers

4

views

Weak vs. Weak* Convergence of Bounded Nets

functional-analysis operator-theory banach-spaces dual-spaces nets

asked 22 mins ago Austin Shiner 153

0

votes

1

answer

12

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Suppose $Y \subseteq \mathbb{R}$ is (Lebesgue) measurable and $X \subseteq Y$ with $\lambda^*(Y \setminus X)=0$. Then is $X$ measurable?

real-analysis solution-verification lebesgue-measure

answered 28 mins ago copper.hat 154k

1

vote

0

answers

9

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Proof that for any $n\in\mathbb{N}$, $n\neq0$, $\exists k\in\mathbb{N}|n=S(k)$

natural-numbers well-orders superalgebra

modified 33 mins ago Thomas Andrews 148k

7

votes

1

answer

232

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Computing $\sum_{n=1}^\infty\frac{4^nH_n^{(3)}}{n^2{2n\choose n}}$

real-analysis integration sequences-and-series binomial-coefficients harmonic-numbers

answered 33 mins ago Dennis Orton 2,261

0

votes

1

answer

38

views

Using likelihood function to createa probability distribution of a binomial probability?

probability-distributions binomial-distribution bayes-theorem

answered 34 mins ago Kenneth K 21

2

votes

1

answer

149

views

What is the essence of ``the naturality of the cap product''?

algebraic-topology differential-topology homology-cohomology geometric-topology poincare-duality

modified 37 mins ago failedentertainment 712

1

vote

1

answer

9

views

Does every bilinear (symmetric) form admit a self-adjoint map representation?

linear-algebra

answered 38 mins ago Igor Rivin 23k

1

vote

1

answer

40

views

If $x^\alpha f$ is in $L^1$, for some $\alpha>0$, then $f$ vanishes at infinity.

real-analysis fourier-analysis smooth-functions

answered 42 mins ago Jason 14.4k

1

vote

1

answer

19

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Dirichlet density of p such that p-1 and p+2 are square mod p

number-theory elementary-number-theory

answered 43 mins ago davidlowryduda♦ 82.6k

1

vote

1

answer

28

views

Study the improper integral for convergence and absolute convergence

integration indefinite-integrals cauchy-integral-formula

modified 44 mins ago Claude Leibovici 189k

0

votes

0

answers

31

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What is the Lebesgue measure of this set?

measure-theory proof-explanation lebesgue-measure convex-geometry geometric-functional-analysis

modified 45 mins ago Shirley Wood 39

0

votes

0

answers

8

views

Why a Lebesgue measure equal to an integral?

lebesgue-measure convex-geometry geometric-measure-theory borel-measures

asked 46 mins ago Shirley Wood 39

2

votes

1

answer

39

views

Muestre que un mapeo continuo y sobre no necesariamente es cerrado

general-topology

answered 46 mins ago Mark Saving 3,618

0

votes

0

answers

11

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Proof about matrix exponentiation with conmutative matrix and Taylor series.

linear-algebra matrices taylor-expansion binomial-coefficients matrix-exponential

asked 50 mins ago Ivan Camilo Ballen Mendez 33

0

votes

0

answers

8

views

Expanding function on [0,1] using Legendre polynomials

fourier-series legendre-polynomials

asked 54 mins ago Nonenicht 37

3

votes

1

answer

17

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Continuity of $f$ and monotone decreasing of $g(x) = \cos(f(x))$ implies uniform continuity of $f$

real-analysis analysis uniform-continuity

answered 59 mins ago Igor Rivin 23k

1

vote

0

answers

17

views

Vector Space as a variety/scheme

algebraic-geometry

asked 1 hour ago take008 640

0

votes

0

answers

17

views

Proving that this cone is a limit cone

category-theory limits-colimits functors

modified 1 hour ago user634426 2,427

1

vote

1

answer

58

views

Need help validating a proof that for any point process with MTBF $t$, the events in an interval sized $u$ will be $\frac{u}{t}$

probability stochastic-processes poisson-process

answered 1 hour ago Rohit Pandey 4,190

1

vote

0

answers

89

views

Finding values of $\theta$ for which $(\cos\theta,\sin\theta)$ lies inside the triangle formed by $x+y=2$, $x−y=1$, and $6x+2y−\sqrt{10}=0$

geometry trigonometry analytic-geometry

modified 1 hour ago Blue 64.3k

0

votes

0

answers

22

views

What is the most efficient way to fill in a circle with a single brushstroke?

geometry

asked 1 hour ago Reneo 314

1

vote

0

answers

17

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Uniqueness and non-uniqueness of a SDE

probability-theory

modified 1 hour ago sharpe 732

0

votes

1

answer

25

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(∀x(s(x) → ¬q(x)) ∧ ∀x((¬p(x) ∧ q(x)) → s(x))) → (∃x(p(x) ∨ q(x)) → ∃xp(x))

logic predicate-logic

answered 1 hour ago Graham Kemp 112k

4

votes

2

answers

57

views

Why do we define Measurable functions by their pre-image?

real-analysis measure-theory

modified 1 hour ago Karl 3,822

1

vote

0

answers

43

views

+200

Questions on the proof of Theorem 14.14 in Matsumura's Commutative Ring Theory.

abstract-algebra algebraic-geometry commutative-algebra

modified 1 hour ago user124697 1,509

1

vote

0

answers

4

views

The maximum eigenvalue of the laplacian of 4-Cayley Tree $T_\infty$

graph-theory laplacian

modified 1 hour ago Mountain 145

0

votes

0

answers

53

views

Does $(n-k)! (k-1)! = n!$?

combinatorics factorial

asked 1 hour ago John S 1

1

vote

0

answers

17

views

Does a straw with two branches have 2 holes?

general-topology

asked 1 hour ago mmmmmm 33

0

votes

0

answers

9

views

What is sufficient liast of information needed to draw phase portrait of a dynamical system?

differential-geometry dynamical-systems

asked 1 hour ago Lakshman Mahto 49

0

votes

1

answer

37

views

Two independent resistors in parallel with normal distribution, what is the mean and variance of it?

statistics improper-integrals normal-distribution residue-calculus

answered 1 hour ago Learning Lin 9

0

votes

0

answers

24

views

Dual version of “representables preserve limits”

category-theory limits-colimits functors representable-functor

modified 1 hour ago user634426 2,427

1

vote

1

answer

23

views

If $p^k m^2$ is an odd perfect number, then is there a constant $D$ such that $\frac{\sigma(m^2)}{p^k} > \frac{m^2 - p^k}{D}$?

number-theory upper-lower-bounds divisor-sum arithmetic-functions perfect-numbers

modified 1 hour ago Arnie Bebita-Dris 8,849

3

votes

0

answers

99

views

What's the sequence $0,9,24,21,36,30,75,120,270,462,837,1320,2085,\ldots$?

sequences-and-series

modified 1 hour ago Blue 64.3k

0

votes

0

answers

29

views

Is an unary relation a set?

elementary-set-theory

modified 1 hour ago Nameless 165

0

votes

0

answers

9

views

Finding number of homomorphisms from $S_4$ to various groups without the First Isomorphism Theorem

group-theory normal-subgroups group-isomorphism group-homomorphism

asked 1 hour ago jaycneek 81

0

votes

0

answers

43

views

Proof for $\det(EA) = \det(E)\det(A)$ where E is an elementary matrix?

linear-algebra determinant

modified 1 hour ago Fei Cao 1,266

0

votes

0

answers

18

views

Is it possible to use MGFs for find the distribution of $X/(X+Y)$ when $X$ and $Y$ are independent and gamma distributed?

probability statistics

modified 1 hour ago Thomas Andrews 148k

0

votes

1

answer

14

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Determining nature of solutions for given Cauchy Data

calculus partial-differential-equations initial-value-problems cauchy-problem

answered 1 hour ago Ricardo Cavalcanti 2,056

1

vote

0

answers

10

views

Showing a sequence converges in product topology.

general-topology

asked 1 hour ago ernesto 275

0

votes

0

answers

6

views

Fast $2$D region containment test

geometry computational-geometry

asked 1 hour ago peng yu 759

0

votes

0

answers

6

views

Sufficient condition for a Weierstrass equation to be minimal when $\text{char}(K)\neq 2,3$

elliptic-curves local-field local-rings

modified 1 hour ago klein4 701

0

votes

0

answers

8

views

How to do queueing theory for a traffic light intersection

real-analysis

asked 1 hour ago Cui 1

1

vote

1

answer

24

views

Convergence almost surely and in $\mathcal{L}^1$ for square of sequence of random variables

probability-theory measure-theory convergence-divergence

answered 2 hours ago user6247850 4,164

0

votes

1

answer

16

views

Are the following range of values on $x_3$ correct given a system of inequalities with 3 variables?

algebra-precalculus inequality

answered 2 hours ago BSplitter 1,199

0

votes

0

answers

7

views

Finding the intersection of an indexed collection

elementary-set-theory

asked 2 hours ago WBuck 101

0

votes

1

answer

24

views

Compute the derivative of a distribution

complex-analysis

answered 2 hours ago kobe 38.1k

0

votes

0

answers

13

views

Brouwer's fixed point theorem with deformation retraction instead of retraction

algebraic-topology fixed-point-theorems

asked 2 hours ago Sergey Rusakov 101

0

votes

2

answers

43

views

Why is $\lim_{x\rightarrow 0}\sin(x*t)/x=t$

limits

modified 2 hours ago Thomas Andrews 148k

1

vote

0

answers

10

views

Why does this finite difference schema converge even though it should be unstable?

ordinary-differential-equations numerical-methods computational-mathematics finite-differences finite-difference-methods

asked 2 hours ago Andrew Mezzi 11

1

vote

0

answers

13

views

Comparison of quantization procedures

partial-differential-equations riemannian-geometry pseudo-differential-operators

asked 2 hours ago felipeh 2,415

2

votes

1

answer

38

views

A proof involving functions

linear-algebra solution-verification

answered 2 hours ago Coriolanus 1,235

0

votes

0

answers

31

views

Showing the operator $Tf=\int_0^tf(s)ds$ Obeys $T^nf=\frac{1}{(n-1)!}\int_0^t (t-s)^{n-1}f(s)ds$

functional-analysis

modified 2 hours ago Cameron Williams 26.6k

0

votes

0

answers

23

views

Showing that something is linear

linear-algebra solution-verification

asked 2 hours ago ANM 141

5

votes

3

answers

130

views

Is there a faster way to compute $\left\lfloor{(k + 1)m \over n}\right\rfloor - \left\lfloor {km\over n}\right\rfloor$?

arithmetic fractions integers ceiling-and-floor-functions computational-mathematics

answered 2 hours ago DanielV 21.3k

2

votes

1

answer

41

views

A group isomorphism $\text{Homeo}(X)\to\text{Aut}(C(X))$?

general-topology group-theory operator-theory c-star-algebras group-homomorphism

answered 2 hours ago Martin Argerami 166k

0

votes

1

answer

17

views

Rotating coordinates of a matrix

linear-algebra linear-transformations

answered 3 hours ago Ralff 961

1

vote

1

answer

16

views

Generate convex polytope partitions from a set of halfspaces

geometry computational-geometry

answered 3 hours ago Glärbo 61

0

votes

0

answers

38

views

+150

Do generic smooth functions have no degenerate points?

real-analysis multivariable-calculus differential-geometry reference-request

modified 3 hours ago Julian Newman 73

0

votes

0

answers

6

views

How can I determine boolean equivalence of a CNF expression?

discrete-mathematics

asked 3 hours ago user7681184 101

0

votes

0

answers

15

views

L1,L2 norm regularization, solving by ADMM.

linear-algebra optimization convex-optimization norm lagrange-multiplier

asked 3 hours ago Sushi man 1

1

vote

0

answers

14

views

Expected number steps in a Birth and Death Chain

probability probability-theory stochastic-processes markov-chains

asked 3 hours ago Isochron 57

2

votes

0

answers

36

views

+100

$k$-homogeneous function

analysis partial-derivative

modified 3 hours ago Lucas cantu 15

-1

votes

1

answer

25

views

Prove that non-descendants of C are conditionally independent given C's parents

probability probability-theory conditional-probability bayesian bayesian-network

answered 3 hours ago Graham Kemp 112k

5

votes

0

answers

19

views

Algebraicity of Pusieux series

abstract-algebra ring-theory field-theory power-series roots

asked 3 hours ago henato4575 119

0

votes

0

answers

4

views

Similar Trapezoids with a median to find Area, with similar ratios

ratio median

asked 3 hours ago Harry Iguana 111

0

votes

0

answers

7

views

Prove the closure complement vectors tending to zero is the complement

real-analysis functional-analysis analysis

asked 3 hours ago IsaKyodo 141

1

vote

0

answers

16

views

Prove that $a$ is minimum of $B$ in $R^{-1}$ if and only if $a$ is maximum of $B$ in $R$.

algebra-precalculus set-theory relations order-theory

asked 3 hours ago Someone 89

1

vote

0

answers

14

views

$R/I$ has finite length as $R$-module iff every associated prime is maximal.

abstract-algebra ring-theory commutative-algebra modules

asked 3 hours ago mathemagician101 11

1

vote

1

answer

12

views

Connected Components of the Homotopy Pullback

homotopy-theory connectedness simplicial-stuff simplicial-complex

answered 4 hours ago Zhen Lin 75.8k

0

votes

0

answers

12

views

Divisibility as an $R$-module vs as an abelian group

ring-theory modules

asked 4 hours ago jacer21 600

0

votes

0

answers

45

views

Can we solve these three sets of equations?

numerical-methods soft-question

modified 4 hours ago Creator 2,777

2

votes

0

answers

29

views

How to find dim(U)

linear-algebra solution-verification

asked 4 hours ago ANM 141

4

votes

0

answers

36

views

Is there a finite theory of groups whose models are all torsion-free?

group-theory first-order-logic model-theory

modified 4 hours ago Noah Schweber 198k

-1

votes

3

answers

42

views

Logarithms, how to prove an identity

logarithms

answered 4 hours ago David 1

1

vote

0

answers

15

views

Schwartz lemma problem $f: \mathbb{D}\rightarrow \mathbb{C}-(-\infty,0]$ and $f(0)=1$

complex-analysis analysis

asked 4 hours ago Ethan Horsfall 581

2

votes

0

answers

43

views

How to show a diagram is a pushout?

category-theory topos-theory pushforward

modified 5 hours ago Sajad 57

0

votes

0

answers

17

views

How to show that $T_k(x_1,\ldots ,x_n)$ is the only polynomial of degree $k$ with the specific properties?

analysis derivatives taylor-expansion partial-derivative

modified 5 hours ago Yassir 1,653

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