Alex Maloney (Ï㽶ÊÓƵ)
Title:ÌýThe Siegel-Weil Formula and Quantum Gravity as an Average.
Abstract:ÌýI will explore the idea that certain theories of gravity are not traditional quantum theories, but are insteadÌýaverages over ensembles of quantumÌýtheories.Ìý Remarkably, this idea can be explored quantitatively using ideas from number theory.ÌýÌýI will consider theÌýaverage overÌýfree boson conformal field theories in two dimensions, and compute theÌýgenus g partition function using the Siegel-Weil formula.ÌýÌýThe result isÌýa real analytic Eisenstein seriesÌýwhich can be interpreted as the sumÌýover geometries in a certain exotic - but in a sense exactly solvable - theory of quantum gravity.ÌýÌýThe techniques used are similar to those used to studyÌýhigh dimensionalÌýsphereÌýpackingÌýbyÌýaveraging over spaces of lattices, suggesting an analogy between semi-classical gravity and a theory of random lattices (orÌýsphereÌýpackings) in high dimensions.Ìý This talk is a review of work done in collaboration with E. Witten, and is intended to be accessible to mathematicians without a specialized physics background.Ìý
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