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Related publications (32)
Relative plus constructions
Let h be a connective homology theory. We construct a functorial relative plus construction as a Bousfield localization functor in the category of maps of spaces. It allows us to associate to a pair (X,H), consisting of a connected space X and an hperfect ...
2023Bounded and unbounded cohomology of homeomorphism and diffeomorphism groups
We determine the bounded cohomology of the group of homeomorphisms of certain low-dimensional manifolds. In particular, for the group of orientation-preserving homeomorphisms of the circle and of the closed 2-disc, it is isomorphic to the polynomial ring g ...
SPRINGER HEIDELBERG2023Collapse-invariant properties of spaces equipped with signals or directions
Collapsing cell complexes was first introduced in the 1930's as a way to deform a space into a topological-equivalent subspace with a sequence of elementary moves. Recently, discrete Morse theory techniques provided an efficient way to construct deformatio ...
EPFL2022Topological Linear System Identification via Moderate Deviations Theory
Daniel Kuhn, Wouter Jongeneel, Tobias Sutter
Two dynamical systems are topologically equivalent when their phase-portraits can be morphed into each other by a homeomorphic coordinate transformation on the state space. The induced equivalence classes capture qualitative properties such as stability or ...
2021Kaleidoscopic groups: permutation groups constructed from dendrite homeomorphisms
Given a transitive permutation group, a fundamental object for studying its higher transitivity properties is the permutation action of its isotropy subgroup. We reverse this relationship and introduce a universal construction of infinite permutation group ...
POLISH ACAD SCIENCES INST MATHEMATICS-IMPAN2019Structural Properties Of Dendrite Groups
Let G be the homeomorphism group of a dendrite. We study the normal subgroups of G. For instance, there are uncountably many nonisomorphic such groups G that are simple groups. Moreover, these groups can be chosen so that any isometric G-action on any metr ...
AMER MATHEMATICAL SOC2019Ising Model: Local Spin Correlations and Conformal Invariance
Clément Hongler, Sung Chul Park
We study the 2-dimensional Ising model at critical temperature on a simply connected subset of the square grid Z2. The scaling limit of the critical Ising model is conjectured to be described by Conformal Field Theory; in particular, there is expected to b ...
Springer2019Kazhdan's Property (T) and Property (FH) for measured groupoids
Introduced 50 years ago by David Kazhdan, Kazhdan's Property (T) has quickly become an active research area in mathematics, with a lot of important results. A few years later, this property has been generalized to discrete group actions by Robert J. Zimmer ...
EPFL2018Cellular Homotopy Excision
There is a classical "duality" between homotopy and homology groups in that homotopy groups are compatible with homotopy pullbacks (every homotopy pullback gives rise to a long exact sequence in homotopy), while homology groups are compatible with homotopy ...
EPFL2016