1,644 research outputs found
Open Problems on Central Simple Algebras
We provide a survey of past research and a list of open problems regarding
central simple algebras and the Brauer group over a field, intended both for
experts and for beginners.Comment: v2 has some small revisions to the text. Some items are re-numbered,
compared to v
Operations in Milnor K-theory
We show that operations in Milnor K-theory mod of a field are spanned by
divided power operations. After giving an explicit formula for divided power
operations and extending them to some new cases, we determine for all fields
and all prime numbers , all the operations
commuting with field extensions over the base field . Moreover, the integral
case is discussed and we determine the operations for
smooth schemes over a field.Comment: to appear in the Journal of Pure and Applied Algebr
Toward a fundamental groupoid for the stable homotopy category
This very speculative sketch suggests that a theory of fundamental groupoids
for tensor triangulated categories could be used to describe the ring of
integers as the singular fiber in a family of ring-spectra parametrized by a
structure space for the stable homotopy category, and that Bousfield
localization might be part of a theory of `nearby' cycles for stacks or
orbifolds.Comment: This is the version published by Geometry & Topology Monographs on 18
April 200
Algebraic K-theory of strict ring spectra
We view strict ring spectra as generalized rings. The study of their
algebraic K-theory is motivated by its applications to the automorphism groups
of compact manifolds. Partial calculations of algebraic K-theory for the sphere
spectrum are available at regular primes, but we seek more conceptual answers
in terms of localization and descent properties. Calculations for ring spectra
related to topological K-theory suggest the existence of a motivic cohomology
theory for strictly commutative ring spectra, and we present evidence for
arithmetic duality in this theory. To tie motivic cohomology to Galois
cohomology we wish to spectrally realize ramified extensions, which is only
possible after mild forms of localization. One such mild localization is
provided by the theory of logarithmic ring spectra, and we outline recent
developments in this area.Comment: Contribution to the proceedings of the ICM 2014 in Seou
On the non-abelian Brumer-Stark conjecture and the equivariant Iwasawa main conjecture
We show that for an odd prime p, the p-primary parts of refinements of the
(imprimitive) non-abelian Brumer and Brumer-Stark conjectures are implied by
the equivariant Iwasawa main conjecture (EIMC) for totally real fields.
Crucially, this result does not depend on the vanishing of the relevant Iwasawa
mu-invariant. In combination with the authors' previous work on the EIMC, this
leads to unconditional proofs of the non-abelian Brumer and Brumer-Stark
conjectures in many new cases.Comment: 33 pages; to appear in Mathematische Zeitschrift; v3 many minor
updates including new title; v2 some cohomological arguments simplified; v1
is a revised version of the second half of arXiv:1408.4934v
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