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2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry beauty bundles calculus categories category category-theory chern-weil-theory cohesion cohesive-homotopy-theory cohesive-homotopy-type-theory cohomology combinatorics complex complex-geometry computable-mathematics computer-science constructive cosmology definitions deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry digraphs duality elliptic-cohomology enriched fibration finite foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry goodwillie-calculus graph graphs gravity group-theory harmonic-analysis higher higher-algebra higher-category-theory higher-differential-geometry higher-geometry higher-lie-theory higher-topos-theory history homological homological-algebra homology homotopy homotopy-theory homotopy-type-theory index-theory integration integration-theory internal-categories k-theory kan lie lie-theory limit limits linear linear-algebra locale localization logic mathematics measure-theory modal modal-logic model model-category-theory monoidal monoidal-category-theory morphism motives motivic-cohomology newpage noncommutative noncommutative-geometry number-theory of operads operator operator-algebra order-theory pasting philosophy physics planar pro-object probability probability-theory quantization quantum quantum-field quantum-field-theory quantum-mechanics quantum-physics quantum-theory question representation representation-theory riemannian-geometry scheme schemes set set-theory sheaf simplicial space spin-geometry stable-homotopy-theory stack string-theory superalgebra supergeometry svg symplectic-geometry synthetic-differential-geometry terminology theory topology topos topos-theory tqft type type-theory universal variational-calculus

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- Discussion Type
- discussion topicanti de Sitter spacetime
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Urs
- Last Active Nov 15th 2018

earlier today I had created a stub for anti de Sitter spacetime

- Discussion Type
- discussion topicBekenstein-Hawking entropy
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 15th 2018

added pointer, here and in related entries, to

- Gary Gibbons, Malcolm J. Perry,
*Black Holes and Thermal Green Functions*, Vol. 358, No. 1695 (1978) (jstor:79482)

being one of the early references considering the computation of black hole radiation in terms of thermal field theory on Wick-rotated spacetimes with compact/periodic “Euclidean time”.

- Gary Gibbons, Malcolm J. Perry,

- Discussion Type
- discussion topiclogarithm
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Nov 13th 2018

- Discussion Type
- discussion topicinferior limit
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Nov 13th 2018

- Discussion Type
- discussion topicInitiality Project - References
- Category Latest Changes
- Started by Alizter
- Comments 8
- Last comment by Mike Shulman
- Last Active Nov 13th 2018

- Discussion Type
- discussion topicwallpaper group
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 13th 2018

- Discussion Type
- discussion topicInitiality Project - Semantics - Pi-types
- Category Latest Changes
- Started by kyod
- Comments 8
- Last comment by kyod
- Last Active Nov 12th 2018

- Discussion Type
- discussion topiccategorical model of dependent types
- Category Latest Changes
- Started by Mike Shulman
- Comments 25
- Last comment by kyod
- Last Active Nov 12th 2018

Created categorical model of dependent types, describing the various different ways to strictify category theory to match type theory and their interrelatedness. I wasn’t sure what to name this page — or even whether it should be part of some other page — but I like having all these closely related structures described in the same place.

- Discussion Type
- discussion topiclattice gauge theory
- Category Latest Changes
- Started by Tim_Porter
- Comments 3
- Last comment by Urs
- Last Active Nov 12th 2018

- Discussion Type
- discussion topiclattice
- Category Latest Changes
- Started by Daniel Luckhardt
- Comments 3
- Last comment by Todd_Trimble
- Last Active Nov 12th 2018

- Discussion Type
- discussion topicPractical Foundations for Programming Languages
- Category Latest Changes
- Started by David_Corfield
- Comments 9
- Last comment by Mike Shulman
- Last Active Nov 12th 2018

The new second edition is recorded at Practical Foundations for Programming Languages plus a link to a description of the changes.

- Discussion Type
- discussion topicRiemann hypothesis
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Nov 12th 2018

added pointer to

- R. P. Brent, J. van de Lune, H. J. J. te Riele and D. T. Winter,
*On the Zeros of the Riemann Zeta Function in the Critical Strip. II*, Mathematics of Computation Mathematics of Computation Vol. 39, No. 160 (Oct., 1982), pp. 681-688 (doi:10.2307/2007345 )

for computer-checks of the Riemann hypothesis. (there are probably more recent such?)

- R. P. Brent, J. van de Lune, H. J. J. te Riele and D. T. Winter,

- Discussion Type
- discussion topicsemi-simplicial set
- Category Latest Changes
- Started by Mike Shulman
- Comments 9
- Last comment by Richard Williamson
- Last Active Nov 12th 2018

Created semi-simplicial set, mainly as a repository for some terminological remarks. I would welcome anyone more knowledgeable about the history to correct or improve it!

- Discussion Type
- discussion topicidempotent semiring
- Category Latest Changes
- Started by Daniel Luckhardt
- Comments 4
- Last comment by DavidRoberts
- Last Active Nov 12th 2018

- Discussion Type
- discussion topicproton spin crisis
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 11th 2018

- Discussion Type
- discussion topiccobordism hypothesis
- Category Latest Changes
- Started by Urs
- Comments 27
- Last comment by Urs
- Last Active Nov 11th 2018

added at cobordism hypothesis a pointer to

- Yonatan Harpaz,
*The Cobordism Hypothesis in Dimension 1*(arXiv:1210.0229)

where the case for $(\infty,1)$-categories is spelled out and proven in detail.

- Yonatan Harpaz,

- Discussion Type
- discussion topicFulton-MacPherson operad
- Category Latest Changes
- Started by Urs
- Comments 19
- Last comment by Todd_Trimble
- Last Active Nov 10th 2018

- Discussion Type
- discussion topicWick rotation
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Urs
- Last Active Nov 10th 2018

added a bit more text to the Idea-section at

*Wick rotation*and in particular added cross-links with*Osterwalder-Schrader theorem*.

- Discussion Type
- discussion topicn-point function
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 10th 2018

- Discussion Type
- discussion topiccomputational trinitarianism
- Category Latest Changes
- Started by Urs
- Comments 28
- Last comment by Urs
- Last Active Nov 10th 2018

created

*computational trinitarianism*, combining a pointer to an exposition by Bon Harper (thanks to David Corfield) with my table logic/category-theory/type-theory.

- Discussion Type
- discussion topicInitiality Project - Raw Syntax - Pi-types
- Category Latest Changes
- Started by Mike Shulman
- Comments 5
- Last comment by Mike Shulman
- Last Active Nov 9th 2018

- Discussion Type
- discussion topicarctangent
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Nov 9th 2018

- Discussion Type
- discussion topicKMS state
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 9th 2018

discovered by chance that we have this stub entry here. Added some lines of an Idea-section and cross-linked with

*thermal quantum field theory*and*Wick rotation*

- Discussion Type
- discussion topicG-structure
- Category Latest Changes
- Started by zskoda
- Comments 14
- Last comment by Urs
- Last Active Nov 9th 2018

I do not understand the entry G-structure. G-structure is, as usual, defined there as the principal $G$-subbundle of the frame bundle which is a $GL(n)$-principal bundle. I guess this makes sense for equivariant injections along any Lie group homomorphism $G\to GL(n)$. The entry says something about spin structure, warning that the group $Spin(n)$ is not a subgroup of $GL(n)$. So what is meant ? The total space of a subbundle is a subspace at least. Does this mean that I consider the frame bundle first as a (non-principal) $Spin(n)$-bundle by pulling back along a fixed noninjective map $Spin(n)\to GL(n)$ and then I restrict to a chosen subspace on which the induced action of Spin group is principal ?

- Discussion Type
- discussion topiccorrelator
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 9th 2018

- Discussion Type
- discussion topiccorrelator as differential form on configuration space of points
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Nov 9th 2018

I was thinking/hoping now that a general approach to perturbative QFT should exist, where all Feynman amplitudes are regarded not as singular distributions on $M^n$, but as smooth differential forms on the FM-compactification of the configuration space of $n$ points. Mentioning this hunch to Igor Khavkine, he immediately recalled having heard Marko Berghoff speak about developing just that in his thesis Berghoff 14.

- Discussion Type
- discussion topicJan Raphael Høegh-Krohn
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Nov 9th 2018

brief category:people-entry for hyperlinking references at

*thermal field theory*

- Discussion Type
- discussion topicspacetime support
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Nov 9th 2018

- Discussion Type
- discussion topicValeri Frolov
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 8th 2018

- Discussion Type
- discussion topicconcordance
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 8th 2018

made more explicit (here) the back-link to

*topological vector bundle*for classical concordance for topological vector bundles