Stack Exchange

Nathaniel Johnston

New Brunswick, Canada

http://www.njohnston.ca/

I am an Assistant Professor at Mount Allison University in Sackville, New Brunswick, Canada. I am interested in quantum entanglement, combinatorics, and matrix analysis.

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Top Questions
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32
Necessary conditions for the existence of solution of Sylvester equation AX=XB
mathoverflow.net

31
Square root of doubly positive symmetric matrices
mathoverflow.net

28
Are infinite planar graphs still 4-colorable?
mathoverflow.net

25
What is the intuition for the trace norm (nuclear norm)?
mathoverflow.net

23
Does $\lfloor(4+\sqrt{11})^{n}\rfloor \pmod {100}$ repeat every $20$ cycles of $n$?
math.stackexchange.com

23
Which theorems have Pythagoras' Theorem as a special case?
mathoverflow.net

17
Does $\lfloor(4+\sqrt[2]{11})^{n}\rfloor mod 100$ repeat every 20 cycles of $n$?
mathoverflow.net

17
positive not completely positive maps
mathoverflow.net

17
Possible values of the determinant for matrices with elements $\{1, 0, -1\}$
mathoverflow.net

16
Operator norm of square root of matrix vs original
mathoverflow.net

16
Find the determinant of a matrix given the determinant of all $p\times p$ sub-matrices?
mathoverflow.net

15
Is there such a thing
mathoverflow.net

14
How hard (P, NP, NP-hard) is it to compute Schur norms of matrices (as multipliers)?
mathoverflow.net

12
Conditions for including cones
mathoverflow.net

11
Linear algebra underlying quantum entanglement?
mathoverflow.net

10
Decomposability of positive maps
mathoverflow.net

10
How to check whether a matrix is completely positive or not?
mathoverflow.net

10
Equivalence of entrywise 1-norm and Schatten-1 norm
mathoverflow.net

10
Product of the entries of a matrix
mathoverflow.net

9
NP-hard problems in linear algebra and real analysis
mathoverflow.net

9
Moments of the trace of orthogonal matrices
mathoverflow.net

9
Is there a name for this type of matrix?
mathoverflow.net

8
Positive-semidefiniteness of a Gram-like matrix
mathoverflow.net

7
elementwise functions of positive definite matrix
mathoverflow.net

7
Powers of traces, integrals over spheres and class functions
mathoverflow.net

7
Tensor product of positive linear maps is positive
mathoverflow.net

7
Solution to a Sylvester equation with positive definite coefficients
mathoverflow.net

6
Non-orthogonal vectors cosine-enhancing transformation
mathoverflow.net

6
Is the solution of this optimization problem always positive semidefinite?
mathoverflow.net

5
Calculating a generalized inverse (Moore–Penrose pseudoinverse)
mathoverflow.net

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