Equivariant formality of the little disks operad

Add to your list(s) Download to your calendar using vCal

• Joana Cirici (Universitat de Barcelona)
• Thursday 19 June 2025, 10:15-11:15
• Seminar Room 1, Newton Institute.

If you have a question about this talk, please contact nobody.

EHTW04 - Beyond the telescope conjecture

I will show that the little n-disks operad is SO(n)- and O(n)-equivariantly formal over the rationals. Equivalently, the oriented and unoriented framed little disks operads are rationally formal as infinity-operads. The approach to prove these results relies on a “purity implies formality” technique. Specifically, we consider the action of the Grothendieck–Teichmüller group on the rationalized little disks operad, constructed using the additivity theorem. This induces an action on the rationalized Borel construction, with special purity properties.  As a consequence of our method, we also establish rational formality for algebraic group actions on smooth complex projective varieties, using Galois action on étale cohomology as input.  This is joint work with Pedro Boavida de Brito and Geoffroy Horel.

This talk is part of the Isaac Newton Institute Seminar Series series.

This talk is included in these lists:

• All CMS events
• Featured lists
• INI info aggregator
• Isaac Newton Institute Seminar Series
• School of Physical Sciences
• Seminar Room 1, Newton Institute
• bld31

Note that ex-directory lists are not shown.