John Klein

Member for 13 years, 5 months
Last seen this week

Metro Detroit. Brooklyn expatriate.

Summary

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18,464

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2020
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Top tag

at.algebraic-topology

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Excavator

Answers

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Score Activity Newest

34

Can anyone explain to me what is an assembly map?

Mar 2, 2012

26

Groupoid actions on spaces

Apr 29, 2011

22

A map inducing isomorphisms on homology but not on homotopy

Aug 12, 2012

19

Fibrations and Cofibrations of spectra are "the same"

Jul 29, 2014

19

Is any CW complex with only finitely many nonzero homology groups homotopic to a finite dimensional CW complex?

Apr 26, 2017

Questions

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Score Activity Newest Views

61

Thomason's "open letter" to the mathematical community

Oct 1, 2021

28

On the (derived) dual to the James construction.

Feb 4, 2011

18

Geometric interpretation of the Pontryagin square

Mar 25, 2011

18

Local homology of a space of unitary matrices

May 2, 2017

17

Transversality in the proof of the Blakers-Massey Theorem. Is it necessary?

Jan 30, 2011

Tags

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at.algebraic-topology

1,050

Score

180

posts

homotopy-theory

401

Score

74

posts

gt.geometric-topology

278

Score

37

posts

differential-topology

165

Score

26

posts

smooth-manifolds

113

Score

22

posts

Reputation

+208

Thomason's "open letter" to the mathematical community

+10

Motivation/interpretation for Quillen's Q-construction?

+10

Iterated quotients in GIT

+10

co-$A_\infty$ spaces

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at.algebraic-topology

Nov 19, 2015
Inquisitive

Jan 4, 2019
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Jun 25, 2013

106

bronze badges

differential-topology

Aug 9, 2021
homotopy-theory

Jun 25, 2013
gt.geometric-topology

May 29, 2014

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54

question votes

173

answer votes