nLab Author — Stephan Alexander Spahn

Overview

Stephan Alexander Spahn has contributed to 288 nLab pages.

Most recent contributions

All pages contributed to

• (infinity,1)-Grothendieck construction
• (infinity,1)-operad
• (infinity,1)-site
• (infinity,1)Cat
• (infinity,n)Cat
• (sub)object classifier in an (infinity,1)-topos
• (∞,1)Operad
• 2Cat
• A-infinity-algebra
• absolute Galois group
• action groupoid
• adjoint (infinity,1)-functor
• affine scheme
• algebraic group
• algebraic variety
• associative operad
• Astérisque
• base change
• Batanin omega-category
• bijective-on-objects functor
• biring
• bisimplicial set
• bisimulation
• boundary of a simplex
• branched manifold
• cartesian reflector
• Cartier duality
• Cat
• categorical distribution
• category object in an (infinity,1)-category
• Cauchy integral theorem
• cellular set
• chain complex
• child's drawing
• classifying (infinity,1)-topos
• classifying topos
• cograph of a functor
• cohesive (infinity,1)-topos
• cohomological dimension
• combinatorics
• compact object
• compact object in an (infinity,1)-category
• complete space
• complex number
• composition
• concurrency theory
• conditional expectation
• connected space
• Conor McBride
• continuum hypothesis
• coverage
• crystalline cohomology
• David A. Cox
• deck transformation
• Demazure, lectures on p-divisible groups
• Demazure, lectures on p-divisible groups, I.1, k-functors
• Demazure, lectures on p-divisible groups, I.10, Frobenius morphism and symmetric products
• Demazure, lectures on p-divisible groups, I.3, open- and closed subfunctors; schemes
• Demazure, lectures on p-divisible groups, I.5, finiteness conditions
• Demazure, lectures on p-divisible groups, I.6, the four definitions of formal schemes
• Demazure, lectures on p-divisible groups, I.7. operations on formal schemes
• Demazure, lectures on p-divisible groups, I.8, constant- and étale schemes
• Demazure, lectures on p-divisible groups, I.9, the Frobenius morphism
• Demazure, lectures on p-divisible groups, II.1, group -functors
• Demazure, lectures on p-divisible groups, II.10, smooth formal groups
• Demazure, lectures on p-divisible groups, II.11, p-divisible formal groups
• Demazure, lectures on p-divisible groups, II.2, constant and étale k-groups
• Demazure, lectures on p-divisible groups, II.3, affine k-groups
• Demazure, lectures on p-divisible groups, II.4, k-formal groups, Cartier duality
• Demazure, lectures on p-divisible groups, II.5, the Frobenius and the Verschiebung morphism
• Demazure, lectures on p-divisible groups, II.6, the category of affine k-groups
• Demazure, lectures on p-divisible groups, II.7, étale and connected formal k-groups
• Demazure, lectures on p-divisible groups, II.8, multiplicative affine groups
• Demazure, lectures on p-divisible groups, II.9, unipotent affine groups, decomposition of affine groups
• Demazure, lectures on p-divisible groups, III.1 the Artin-Hasse exponential series
• Demazure, lectures on p-divisible groups, III.2, the Witt rings over Z
• Demazure, lectures on p-divisible groups, III.3, the Witt rings over k
• Demazure, lectures on p-divisible groups, III.4, duality of finite Witt groups
• Demazure, lectures on p-divisible groups, III.5, Dieudonné modules (affine unipotent groups)
• Demazure, lectures on p-divisible groups, III.6, Dieudonné modules (p-torsion finite k-groups)
• Demazure, lectures on p-divisible groups, III.8, Dieudonné modules (p-divisible groups)
• Demazure, lectures on p-divisible groups, III.9, Dieudonné modules (connected formal groups of finite type)
• Demazure, lectures on p-divisible groups, IV.1, isogenies
• Demazure, lectures on p-divisible groups, V.2, points of finite order and endomorphisms
• descent object
• determinant
• diagonalizable group scheme
• Dieudonne module
• Dieudonné ring
• differential cohesive (infinity,1)-topos
• directed object
• discrete object
• display map
• display of a p-divisible group
• divisible group
• Dold-Kan correspondence
• domain opfibration
• double negation
• duality
• E-infinity-ring
• effect algebra
• effect algebra of predicates
• empty 011
• empty 012
• enriched category
• enriched model category
• epipresheaf
• equalizer
• equivalence
• etale scheme
• existential quantifier
• factorization lemma
• fibration fibered in groupoids
• fibration of quasi-categories
• filtered (infinity,1)-category
• filtered colimit
• forcing
• formal group
• formal scheme
• formally étale morphism
• free loop space object
• Frobenius morphism
• fundamental (infinity,1)-category
• fundamental group
• Galois connection
• Galois group
• Galois module
• Galois theory
• generalized algebraic theory
• geometric homotopy groups in an (infinity,1)-topos
• geometry (for structured (infinity,1)-toposes)
• Giuseppe Primiero
• globular set
• Goodwillie calculus
• graph
• Grothendieck construction
• Grothendieck's Galois theory
• group algebra
• group functor
• group object
• group scheme
• groupoid object
• Grpd
• Haskell
• Hazewinkel, Witt vectors
• higher algebra
• Hochschild-Witt complex
• homotopy level
• homotopy limit
• homotopy type theory
• homotopy type theory - contents
• HoTT methods for homotopy theorists
• hypergraph
• I.10, Frobenius morphism and symmetric products
• idempotent complete (infinity,1)-category
• idempotent monad
• inaccessible cardinal
• ind-object
• indexed category
• indexed functor
• inertia orbifold
• infinity-algebra over an (infinity,1)-operad
• infinity-category
• infinity-connected (infinity,1)-topos
• Infinity-Grpd
• information theory
• injective object
• internal infinity-groupoid
• internal site
• interval object
• inverse Galois problem
• jointly epimorphic family
• Joseph Goguen
• k-ring of functions on a k-functor
• Kan complex
• Kan object
• Lambda-ring
• Lars Hesselholt
• Lawvere-Tierney topology
• little cubes operad
• local formal group scheme
• local geometric morphism
• locally algebraic scheme
• locally cartesian closed category
• locally internal category
• locally n-connected (n+1,1)-topos
• locally representable structured (infinity,1)-topos
• main theorem of classical Galois theory
• mapping simplex
• Martin-Löf dependent type theory
• measure theory
• minimal inner fibration
• mixed characteristic
• model structure for Cartesian fibrations
• modules over a ring are equivalent to quasicoherent sheaves over its spectrum
• monads in Haskell
• monomorphism in an (infinity,1)-category
• Moore path category
• Morita equivalence
• multiplicative group scheme
• Möbius inversion
• n-truncated object of an (infinity,1)-category
• nerve and realization
• nilradical
• non-commutative Witt vectors
• open morphism
• Operad
• orbifold
• orbifold groupoid
• order of a group
• ordinal sum
• oriental
• p-divisible group
• p-torsion
• paracompact topological space
• partial order
• path space object
• plus construction
• plus construction on presheaves
• point of a topos
• polynomial functor
• polynomial monad
• Pos
• pre-abelian category
• pro-object
• probability theory
• Prof
• profinite group
• projectively cofibrant diagram
• proper geometric morphism
• proper morphism
• quantum information
• quasi-pullback
• realizer
• reflective subcategory
• Rel
• relations of certain classes of group schemes
• relatively k-compact morphism in an (infinity,1)-category
• restriction of scalars
• right/left Kan fibration
• rigid analytic geometry
• rigid monoidal category
• ring of Witt vectors
• scheme
• Segal condition
• segment object
• semigroup
• Set
• seven trees in one
• shape modality
• simplex category
• simplicial scheme
• Some geometric perspectives in concurrency theory
• spectrum
• spectrum - disambiguation
• sphere spectrum
• split idempotent
• Stephan Alexander Spahn
• Stokes theorem
• straightening functor
• structured (infinity,1)-topos
• substitution natural deduction - table
• T. Streicher - a model of type theory in simplicial sets - a brief introduction to Voevodsky' s homotopy type theory
• Tate module
• the Barsotti-Tate group of an abelian variety
• the fundamental group and Galois theory
• the fundamental theorem of Galois theory
• thin category
• totally disconnected space
• tree category
• Trimble n-category
• type theory
• type theory - contents
• types and calculus
• undirected object
• unipotent group scheme
• variety
• Voevodsky motive
• W-type
• weighted homotopy theory
• Weinstein, the geometry of Lubin-Tate spaces
• Witt ring
• Witt ring of equivalence classes of bilinear forms
• Witt vectors > history
• Yoneda lemma
• Young diagram
• zero object
• étale site