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Yemon Choi

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Name	Yemon Choi
Member for	3 years
Seen	58 mins ago
Website	ifwisdomwereteachable.wordpress.com
Location	Saskatoon
Age

Assistant Professor at the University of Saskatchewan. Firm believer that "they also serve who only stand and wait".

Mainly working these days on abstract harmonic analysis, but always liable to fall off the wagon and into the cohomology of Banach algebras. Other interests currently include: homological perspectives on functional analysis; probabilistic methods; convolution operators arising from group actions.

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39

Questions

votes newest views recent

8

26

votes

1

answer

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Is the set of primes “translation-finite”?

nt.number-theory co.combinatorics analytic-number-theory fourier-analysis open-problem

nov 19 09 at 6:22 Yemon Choi 8,608●1●20●45

8

16

votes

2

answers

603

views

Does left-invertible imply invertible in full group C*-algebras (discrete case)?

c-star-algebras oa.operator-algebras

oct 28 11 at 7:31 Andreas Thom 13.1k●1●23●65

4

15

votes

2

answers

712

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Groups of order $n$ with a character whose degree is at least $0.8\sqrt{n}$ (say)

gr.group-theory characters finite-groups

jun 23 11 at 23:15 Geoff Robinson 10.4k●1●22●29

4

13

votes

2

answers

604

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“Explicit” embedding of $\ell^1$ as a closed subalgebra of a direct sum of matrix algebras

oa.operator-algebras matrices fa.functional-analysis

dec 18 10 at 10:31 Mikael de la Salle 3,466●5●16

12

votes

6

answers

415

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Invertibility of a certain matrix indexed by the Hamming cube

co.combinatorics matrices sp.spectral-theory

mar 9 at 2:02 Brendan McKay 9,179●1●15●34

5

11

votes

2

answers

810

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Approximating operators on Banach spaces by bounded operators on a proper dense subspace

banach-spaces

jul 11 10 at 11:35 Bill Johnson 14.5k●1●33●60

3

11

votes

1

answer

409

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A left inverse for the comultiplication on a Hopf von Neumann algebra

oa.operator-algebras quantum-groups von-neumann-algebras

nov 30 11 at 9:41 Matthew Daws 5,547●1●8●29

1

11

votes

1

answer

302

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Is the space of Hankel operators complemented in B(H)?

fa.functional-analysis operator-theory reference-request banach-spaces

nov 16 11 at 20:50 Yemon Choi 8,608●1●20●45

1

10

votes

0

answers

251

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Can we find arbitrarily many elements of SU(2) generating a good copy of MAX($\ell_1^n$) inside VN(SU(2))?

oa.operator-algebras banach-spaces rt.representation-theory

oct 24 at 14:30 Yemon Choi 8,608●1●20●45

1

10

votes

4

answers

664

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Can we bound degrees of complex irreps in terms of the average conjugacy class size?

gr.group-theory finite-groups rt.representation-theory

apr 30 11 at 7:27 Geoff Robinson 10.4k●1●22●29

169

Answers

votes newest views recent

Not especially famous, long-open problems which anyone can understand

Which journals publish expository work?

What is the main goal of a paper, really?

Geometric Interpretation of Trace

Eigenvalues of Matrix Sums

Describe a topic in one sentence.

Is there a compact group of countably infinite cardinality?

Books you would like to read (if somebody would just write them…)

Does there exist a continuous function of compact support with Fourier transform outside L^1?

Why do so many textbooks have so much technical detail and so little enlightenment?

Fundamental problems whose solution seems completely out of reach (2)

Is Thompson’s group F residually finite?

How to select a journal?

Do torsion-free groups give projectionless group ($C^\ast$) algebras?

Epimorphisms have dense range in TopHausGrp?

Is Fourier analysis a special case of representation theory or an analogue?

Interesting applications of the Pigeon-hole Principle

Subgroups of $\mathbb{Z}^n$

Probabilistic Proofs of Analytic Facts

Looking for an introductory textbook on algebraic geometry for an undergraduate lecture course

Characterizing specific “concrete” mathematical objects by abstract general properties (2)

Dimensions of unitary representations of group extensions

Pathological Examples of Dimension

Compactly generated Banach spaces

Mittag-Leffler condition: what’s the origin of its name?

What are fixed points of the Fourier Transform

How exactly is Hochschild homology a monad homology? (2)

What’s a groupoid? What’s a good example of a groupoid?

Finding questions between functional analysis and set theory

Banach spaces with few linear operators ?

5080

Votes

3935

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131

Tags

fa.functional-analysis× 54
oa.operator-algebras× 29
reference-request× 21
gr.group-theory× 18
big-list× 16
soft-question× 15
banach-spaces× 15
ct.category-theory× 14
fourier-analysis× 12
c-star-algebras× 12

matrices× 11
von-neumann-algebras× 10
pr.probability× 10
banach-algebras× 10
ca.analysis-and-odes× 9
rt.representation-theory× 8
linear-algebra× 8
lie-groups× 6
hilbert-spaces× 6
gn.general-topology× 6

finite-groups× 6
co.combinatorics× 6
ag.algebraic-geometry× 6
semigroups× 5
open-problem× 5
nt.number-theory× 5
lie-algebras× 5
ho.history-overview× 5
examples× 5
dg.differential-geometry× 5

ac.commutative-algebra× 5
real-analysis× 4
noncommutative-geometry× 4
measure-theory× 4
homological-algebra× 4
cv.complex-variables× 4
books× 4
big-picture× 4
terminology× 3
operator-theory× 3

noncommutative-algebra× 3
monoids× 3
mathematics-education× 3
gm.general-mathematics× 3
geometry× 3
complex-analysis× 3
topological-groups× 2
textbook-recommendation× 2
teaching× 2
st.statistics× 2

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