We invite applications for up to two Postdoctoral Research Associates to work with Professors Ulrike Tillmann, Vidit Nanda and Heather Harrington on an exciting project in applied topology for data science with links to geometry and systems biology. These are full-time, fixed-term positions for 24 months funded by a Centre-to-Centre research grant from the EPSRC. The start-date for these positions are flexible, but September – October 2026 is preferred.
13:15
Geometric and topological potentials driving self-assembly
Abstract
Oxford University Club Cricket Club (OUCCC) is a friendly and inclusive cricket club for Oxford University staff, graduate students, and alumni, and we’d love to welcome new players this season. We play relaxed 40-over fixtures almost every Sunday from April to September, take a break in July for our popular mini T20 World Cup, and run weekly outdoor nets from February onwards (weather permitting). Players of all abilities are very welcome.
11:00
On Booleanizations of theories
Abstract
I will introduce the concept of Booleanization of a theory and state some examples, including ring of adeles of number fields and sheaves of structures, and discuss some model theoretic properties.
This is joint work with Ehud Hrushovski from
Jamshid Derakhshan and Ehud Hrushovski, Imaginaries, Products, and the Adele
Ring, https://arxiv.org/abs/2309.11678v3
12:45
Krylov complexity and the universal operator growth hypothesis
Abstract
A central goal in the study of quantum chaos is being able to make universal statements about the dynamics of generic Hamiltonian systems. Under time evolution, an initially local operator progressively explores the Hilbert space of a system becoming increasingly non-local in the process. We will see that this idea lends itself to a natural notion of operator complexity measured (in the Hilbert space of operators) by the overlap of a time-evolving operator with a basis naturally adapted to time evolution and stratified by the growth in the operator's support. The information contained in this so-called Krylov basis is encoded in a sequence called the Lanczos coefficients which quantify the rate at which an operator is "pushed" along the Krylov basis to successively more complex elements. The universal operator growth hypothesis is then the conjecture that the Lanczos coefficients grow asymptotically linearly in any quantum chaotic system. In this talk, I will present an overview of these ideas and see how they manifest in the example of the well-studied SYK model. This talk is primarily based on 1812.08657.