17 citations · 17 across the 9 of their papers we have counts for
9 papers
Action principality as a Lie-group certificate
Alexandru Chirvasitu
A continuous action of a topological group is principal if its isotropy groups are all conjugate to and the quotient map…
Equivariant compactifications, trivial embeddability and finite type
Alexandru Chirvasitu
We characterize finite-type -principal -equivariant bundles on normal -spaces for compact Lie groups and , in several w…
Irremediably singular quantum branched covers
Alexandru Chirvasitu
We prove that the Natsume-Olsen non-commutative spheres dualize for rational deformation parameters to provide examples of quantum branched covers over their…
Obstructed subhomogeneous-bundle extensions and embeddings
Alexandru Chirvasitu
We address a number of problems concerning the (im)possibility of either extending locally trivial subbundles of possibly singular Banach/ bundles globally, embedding subhomog…
Eigenvalue collision and exotic preservers on semisimple operators
Alexandru Chirvasitu
We classify -matrix-valued continuous commutativity and spectrum preservers defined on spaces of (a) normal, (b) semisimple and (c) arbitrary matrices with s…
Spectral finiteness, quantum norm continuity and classical points
Alexandru Chirvasitu
We prove various notions of uniform continuity for compact-quantum-group representations on Hilbert or Banach spaces equivalent to having finite spectrum, i.e. finitely many isotyp…
Uniformity and isotypic smallness for quantum-group representations
Alexandru Chirvasitu
Compact-group representations on Banach spaces are known to be norm-continuous precisely when they have finite spectra. For a quantum group with continuous-function algebra $\mathc…
Banach manifolds of spectrally small quantum-group representations
Alexandru Chirvasitu
We prove that finite-spectrum representations of compact quantum groups either in unital -algebras or on Banach spaces exhibit the same Banach-space-modeled differenti…
The fundamental pro-groupoid of an affine 2-scheme
Alexandru Chirvasitu, Theo Johnson-Freyd
A natural question in the theory of Tannakian categories is: What if you don't remember $\Forget$? Working over an arbitrary commutative ring , we prove that an answer to this q…