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Calendar of Physics Talks Vienna
| Anomalous field theories as boundaries |
| Speaker: | Lukas Müller (Heriot-Watt University, Edinburgh) |
| Abstract: | This talk will be about the description of anomalies in quantum field theory through boundary states of certain field theories in one dimensions higher.
I will give a gentle introduction to the mathematical formulation of this approach developed by Freed and Monnier and explain its relation to more classical approaches.
I will discuss two concrete examples in detail, namely the parity anomaly of fermionic gauge theories in odd spacetime dimensions and 't Hooft anomalies of discrete gauge theories.
Time permitting I will mention some open questions related to smooth families of field theories. The talk is based on joint work with R. J. Szabo. |
| Date: | Tue, 09.03.2021 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | ZOOM: https://moodle.univie.ac.at/mod/bigbluebuttonbn/guestlink.php?gid=x8o6ILSKJuC9 |
| Contact: | S. Fredenhagen, D. Grumiller, T. Schimannek |
| REvolver: Automated running and matching of couplings and masses in QCD |
| Speaker: | Christopher Lepenik (Univ. Wien) |
| Abstract: | In this talk, I present the recently released C++ (+MathLink +Python) library "REvolver", which focuses on fast and precise running, matching, and conversion of QCD parameters.
REvolver provides an easy-to-use setup for renormalization group evolution with automatic matching of the QCD coupling and quark masses in the MSbar and MSR scheme, as well as conversion between various quark mass renormalization schemes. For most precise mass scheme conversion the effects originating from lighter massive quark flavors are implemented, and potentially large logs of characteristic scale ratios are resummed by utilizing R-evolution (IR-renormalization group flow).
After reviewing some of the fundamental concepts and ideas behind quark mass renormalization schemes and R-evolution, some details of the code and its usage are discussed, including a live demo. |
| Date: | Tue, 09.03.2021 |
| Time: | 16:00 |
| Duration: | 60 min |
| Location: | https://univienna.zoom.us/j/93104933847?pwd=N0FrL0E1UHlkQWRhQTlQODVkZ3kvUT09 Meeting ID: 931 0493 3847 Passcode: 674625 |
| Contact: | A. Hoang, P. Stoffer |
| Classically gravitating quantum systems: causality, entanglement, and experimental tests |
| Speaker: | André Großardt (Jena) |
| Abstract: | I will motivate the idea of quantum fields on a classical spacetime as a fundamental theory, giving rise to dynamics governed by the nonlinear Schrödinger-Newton equation in the nonrelativistic limit. I discuss the issue that arises from this nonlinear evolution regarding causality and how it may be avoided in a model that encompasses a mechanism for objective wave function collapse. I will further discuss gravity-induced entanglement as a proxy for the quantisation of gravity, and argue that experimental tests of quantum versus semiclassical gravity through entanglement generation are strongly constrained by acceleration noise. |
| Date: | Thu, 11.03.2021 |
| Time: | 15:00 |
| Duration: | 60 min |
| Location: | ZOOM: https://univienna.zoom.us/j/6540036841?pwd=SytyVkZJZzNyRG9lMm13ejlHeHRRUT09 Meeting ID: 654 003 6841 Passcode: Gs4brS |
| Contact: | Piotr Chrusciel, David Fajman |
| Resolving spacetime singularities in flux compactifications and KKLT |
| Speaker: | Jakob Moritz (Cornell) |
| Abstract: | I explain how string theory resolves ubiquitous singularities in type IIB flux compactifications (and eventually KKLT de Sitter vacua) via effects that are non-perturbative in the \alpha' expansion of string theory. I will show that these can be understood in detail by mapping them to well known gauge instanton effects in pure 4d N=2 Yang-Mills theory. A perhaps surprising consequence is that the naively 'elementary' D7 brane of type IIB string theory is properly thought of as a bound state of two mutually non-local cosmic defects in six dimensions upon compactification on a curved 4-manifold. Finally, I will argue that the resolution described indicates that KKLT de Sitter vacua can be controlled by a small flux superpotential although the K\"ahler potential may in general receive large corrections which are difficult to compute. |
| Date: | Thu, 11.03.2021 |
| Time: | 16:30 |
| Location: | https://tuwien.zoom.us/j/95482849369?pwd=SkU2WU5hMVJBQWsyVlFXRlRvQlIvdz09 |
| Contact: | Laura Donnay, Niccolo Cribiori |
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