3,564 reputation
1236
bio website maths.swan.ac.uk/staff/jhg
location Swansea, Wales, UK
age 32
visits member for 4 years
seen 2 days ago
Lecturer at Swansea University. Topologist. Interested in homotopy theory of moduli spaces and operads.

Mar
25
awarded  Yearling
Mar
25
awarded  Nice Answer
Feb
24
awarded  Nice Answer
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awarded  Popular Question
Nov
23
awarded  Nice Answer
Nov
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awarded  Nice Answer
Jun
25
awarded  at.algebraic-topology
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27
awarded  Nice Answer
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awarded  Nice Question
Apr
24
comment A_infinity structure on cohomology and the weight filtration
Dan, thanks for reminding me about that question - I had forgotten about it. Unfortunately nobody ever gave an answer to that one.
Apr
24
comment A_infinity structure on cohomology and the weight filtration
Jan, even without knowing that smooth projective implies formal, smooth projective implies immediately that weight equals degree.
Apr
24
asked A_infinity structure on cohomology and the weight filtration
Mar
25
awarded  Yearling
Mar
12
comment Which manifolds are homeomorphic to simplicial complexes?
Ciprian Manolescu has just posted a paper in which he claims to prove that no such homology 3-sphere exists. arXiv:1303.2354 Pin(2)-equivariant Seiberg-Witten Floer homology and the Triangulation Conjecture
Feb
19
revised Is a map a homotopy equivalence if its suspension is so?
added 52 characters in body
Nov
26
asked The Damworld model of Hamilton and Henderson
Sep
29
awarded  Nice Answer
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awarded  Enlightened
Aug
28
awarded  Nice Answer
Aug
26
comment Homotopy theory of topological stacks/orbifolds
If you build the Borel construction in the right way then the map from the homotopy quotient to the coarse quotient will have as its fibres the classifying spaces of the isotropy groups. If the isotropy groups are all finite then their classifying spaces have trivial rational cohomology and a version of the Vietoris Mapping Theorem gives the rational equivalence asked for in Q2. Alternatively, one could take singular simplicial sets and use a spectral sequence argument.