User Robert Israel - MathOverflow

Robert Israel

Member for 13 years, 1 month
Last seen this week

math.ubc.ca/~israel
Toronto, ON, Canada

1,089 Answers

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4 votes

On $XX'=I$ such that $AX=XB$ is true

answered Dec 7, 2015 at 1:14

4 votes

Accepted

How large can a subset of $\{1,\ldots,N\}$ be if all pairwise LCMs of its elements are lower bounded?

answered Nov 6, 2015 at 1:03

4 votes

Stone-Weierstrass Theorem, polynomial interpolation, divided difference in complex plane

answered Oct 15, 2015 at 23:18

4 votes

Central binomials and irrationals

answered Aug 10, 2015 at 17:50

4 votes

Accepted

Choosing k pairs l distance apart from n numbers

answered Jun 11, 2015 at 16:04

4 votes

Accepted

Which irrationals yield bounded sets of iterates?

answered May 12, 2015 at 0:49

4 votes

Solutions of the equation $2^{q-1} \equiv q \pmod {4q^2+1 }$ where $q$ is an odd prime

answered Jun 2, 2015 at 6:06

4 votes

How many unit simplices are needed to cover a unit $n$-cube?

answered Apr 8, 2015 at 1:16

4 votes

Accepted

Positive definiteness of infinite tridiagonal matrices

answered Feb 12, 2015 at 20:37

4 votes

Accepted

Accuracy of the formulas for angles between almost colinear vectors

answered Feb 12, 2015 at 20:53

4 votes

What are interesting heuristics of determining how far given matrix is from a singular one?

answered Mar 19, 2015 at 15:24

4 votes

Accepted

Sampling point uniformly at random satisfying equality constraints

answered Jan 22, 2015 at 0:15

4 votes

Accepted

Examples of potentials for which Schrödinger equation lacks discrete points in continuous spectrum

answered Jan 6, 2015 at 16:42

4 votes

Nepero game (by Yacov Perelman)

answered Jan 8, 2015 at 23:03

4 votes

Estimate maximal coefficient of a polynomial from a circle containing all roots

answered Jul 23, 2014 at 16:28

4 votes

An interesting calculation of derivative

answered Aug 21, 2014 at 15:46

4 votes

Nearby matrices have nearby leading eigenvectors?

answered Sep 8, 2014 at 18:18

4 votes

Examples of intuition from fields other than Physics to solve math problems

answered Sep 17, 2014 at 4:59

4 votes

Accepted

Monotonicity of Trapezoid Approximations

answered Sep 10, 2014 at 17:18

4 votes

Accepted

Connection between eigenvalues of A and its LDL decomposition

answered Sep 23, 2014 at 18:20

4 votes

The distribution of the shortest path through $n$ points

answered Oct 6, 2014 at 20:00

4 votes

Accepted

Determinant of block covariance matrix

answered Oct 28, 2014 at 2:31

4 votes

Approximate Moment Conditions

answered Jul 11, 2014 at 0:36

4 votes

Finding the set of all $0$-$1$ vectors in an affine subspace

answered Jul 7, 2014 at 18:12

4 votes

Asymptotics and error terms for an arithmetic function built upon $\omega$ and $\Omega$ functions

answered Jul 21, 2014 at 22:11

4 votes

Accepted

a question regarding the interchange the order of finite summation with finite integration

answered May 1, 2014 at 6:56

4 votes

How to examine the convexity of a complex function numerically?

answered Oct 3, 2013 at 6:12

4 votes

Recognizing parallelogram tilings from their vertex set

answered Sep 11, 2013 at 4:48

4 votes

Accepted

Combination of 2 × 1 × 1 cubes inside a 3 × 3 × n cube

answered Oct 13, 2013 at 18:25

4 votes

Accepted

"Letters and Numbers" Numbers game

answered Jun 7, 2011 at 15:09

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