11:30
Non-archimedean parametrizations and some bialgebraicity results
Abstract
We will provide a general overview on some recent work on non-archimedean parametrizations and their applications. We will start by presenting our work with Cluckers and Comte on the existence of good Yomdin-Gromov parametrizations in the non-archimedean context and a $p$-adic Pila-Wilkie theorem. We will then explain how this is used in our work with Chambert-Loir to prove bialgebraicity results in products of Mumford curves.
14:15
From calibrated geometry to holomorphic invariants
Abstract
Calibrated geometry, more specifically Calabi-Yau geometry, occupies a modern, rather sophisticated, cross-roads between Riemannian, symplectic and complex geometry. We will show how, stripping this theory down to its fundamental holomorphic backbone and applying ideas from classical complex analysis, one can generate a family of purely holomorphic invariants on any complex manifold. We will then show how to compute them, and describe various situations in which these invariants encode, in an intrinsic fashion, properties not only of the given manifold but also of moduli spaces.
Interest in these topics, if initially lacking, will arise spontaneously during this informal presentation.
Anna Seigal, one of Oxford Mathematics's Hooke Fellows and a Junior Research Fellow at The Queen's College, has been awarded the 2020 Society for Industrial and Applied Mathematics (SIAM) Richard C. DiPrima Prize. The prize recognises an early career researcher in applied mathematics and is based on their doctoral dissertation.
Compressed Sensing or common sense?
Abstract
We present a simple algorithm that successfully re-constructs a sine wave, sampled vastly below the Nyquist rate, but with sampling time intervals having small random perturbations. We show how the fact that it works is just common sense, but then go on to discuss how the procedure relates to Compressed Sensing. It is not exactly Compressed Sensing as traditionally stated because the sampling transformation is not linear. Some published results do exist that cover non-linear sampling transformations, but we would like a better understanding as to what extent the relevant CS properties (of reconstruction up to probability) are known in certain relatively simple but non-linear cases that could be relevant to industrial applications.