English

Chromatic Noshift

K-Theory and Homology 2026-04-03 v1 Algebraic Topology Category Theory

Abstract

The chromatic redshift philosophy, introduced by Ausoni and Rognes, suggests that algebraic KK-theory raises chromatic height by 11. We show that the analogue of this philosophy fails in the case of rigid symmetric monoidal stable \infty-categories. More precisely, we construct examples of rigid T(n)T(n)-local categories CC where a refinement Dim\mathrm{Dim} of the dimension morphism induces an equivalence K(C)End(1C)BS1K(C)\to \mathrm{End}(\mathbf{1}_C)^{BS^1} and for which K(C)K(C) therefore vanishes T(n+1)T(n+1)-locally. In fact, we prove that this equivalence always holds for 1\aleph_1-Nullstellensatzian rigid T(n)T(n)-local categories in the sense of Burklund, Schlank and Yuan. We study more in depth the rational version of these results to find a rigid rational additive 11-category witnessing the failure of redshift at height 00. Finally, we use our methods to prove and generalize a conjecture of Levy about categorification of ordinary rings.

Cite

@article{arxiv.2604.01863,
  title  = {Chromatic Noshift},
  author = {Maxime Ramzi},
  journal= {arXiv preprint arXiv:2604.01863},
  year   = {2026}
}

Comments

47 pages, comments welcome !

R2 v1 2026-07-01T11:50:44.204Z