193 research outputs found
G-symmetric spectra, semistability and the multiplicative norm
In this paper we develop the basic homotopy theory of G-symmetric spectra
(that is, symmetric spectra with a G-action) for a finite group G, as a model
for equivariant stable homotopy with respect to a G-set universe. This model
lies in between Mandell's equivariant symmetric spectra and the G-orthogonal
spectra of Mandell and May and is Quillen equivalent to the two. We further
discuss equivariant semistability, construct model structures on module,
algebra and commutative algebra categories and describe the homotopical
properties of the multiplicative norm in this context.Comment: Final published versio
Symmetric products and subgroup lattices
Let G be a finite group. We show that the rational homotopy groups of
symmetric products of the G-equivariant sphere spectrum are naturally
isomorphic to the rational homology groups of certain subcomplexes of the
subgroup lattice of G.Comment: final published versio
Commuting matrices and Atiyah's Real K-theory
We describe the -equivariant homotopy type of the space of commuting
n-tuples in the stable unitary group in terms of Real K-theory. The result is
used to give a complete calculation of the homotopy groups of the space of
commuting n-tuples in the stable orthogonal group, as well as of the
coefficient ring for commutative orthogonal K-theory.Comment: Minor changes. To appear in Journal of Topolog
Symmetric products, subgroup lattices and filtrations of global K-theory
This thesis consists of two projects in equivariant stable homotopy theory. In the first we study the rational homotopy groups of symmetric products of the G-sphere spectrum and show that they are naturally isomorphic to the rational homology groups of certain subcomplexes of the subgroup lattice of G. In the second we investigate global equivariant versions of spectrum level filtrations introduced by Arone and Lesh which interpolate between topological/algebraic K-theory and the Eilenberg-MacLane spectrum for the integers. We determine the global homotopy type of the subquotients and use this description to obtain algebraic formulas for filtrations of representation rings that arise on 0-th homotopy groups
The Neuromodulatory Effects of Sex Hormones on Functional Cerebral Asymmetries and Cognitive Control
Nearly 20 years ago, Hausmann and GĂźntĂźrkĂźn (2000a, 2000b) published a review article in the Journal of Neuropsychology/Zeitschrift fĂźr Neuropsychologie on the influences of sex hormones on functional cerebral asymmetries (FCAs). They further presented a neuroendocrinological model (Hausmann & GĂźntĂźrkĂźn, 2000c) that could potentially explain how sex hormones modulate FCAs. Their model proposed that high levels of progesterone reduce the synaptic efficiency of cortico-cortical transmission, leading to a reduction of FCAs. However, empirical data testing their hypothesis directly were missing. Using various approaches, we have now gathered behavioral, electrophysiological, and neuroimaging data that partly support the original idea, while also pointing toward estradiol-modulating FCAs. The current review provides an update on this fascinating topic and briefly explores clinical applications
Invariant prime ideals in equivariant Lazard rings
Let be an abelian compact Lie group. In this paper we compute the
spectrum of invariant prime ideals of the -equivariant Lazard ring, or
equivalently the spectrum of points of the moduli stack of -equivariant
formal groups. We further show that this spectrum is homeomorphic to the Balmer
spectrum of compact -spectra, with the comparison map induced by equivariant
complex bordism homology.Comment: 43 pages, comments welcom
Proper Equivariant Stable Homotopy Theory
All five authors were supported by the Hausdorff Center for Mathematics at the University of Bonn (DFG GZ 2047/1, project ID 390685813) and by the Centre for Symmetry and Deformation at the University of Copenhagen (CPH-SYM-DNRF92); we would like to thank these two institutions for their hospitality, support and the stimulating atmosphere. Hausmann, Patchkoria and Schwede were partially supported by the DFG Priority Programme 1786 âHomotopy Theory and Algebraic Geometryâ. Work on this monograph was funded by the ERC Advanced Grant âKL2MG-interactionsâ of L¨uck (Grant ID 662400), granted by the European Research Council. Patchkoria was supported by the Shota Rustaveli National Science Foundation Grant 217-614. Patchkoria and Schwede would like to thank the Isaac Newton Institute for Mathematical Sciences for support and hospitality during the programme âHomotopy harnessing higher structuresâ, when work on this paper was undertaken (EPSRC grant number EP/R014604/1). We would also like to thank Bob Oliver and Søren Galatius for helpful conversations on topics related to this project, and the anonymous referee for his or her careful reading and the many useful comments.Peer reviewedPostprin
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