Physik-Combo

22 Mar 2021, 08:50 → 24 Mar 2021, 18:45 Europe/Berlin

The Physik-Combo - a transregional training initiative of the RTG 2522 Jena Leipzig - provides in-depth research training in topical areas in the context of "Strong Dynamics and Criticality in Quantum and Gravitational Systems".

Its program consists of compact lecture courses delivered by invited experts in the field and project talks contributed by the RTG fellows and guests.

The Physik-Combo continues the tradition of the Mitteldeutsche Physik-Combo. 

workshop-foto.png

Monday 22 March

08:50 → 09:00 Opening address

Speaker: Holger Gies (TPI, FSU Jena)

09:00 → 09:30 Towards exact FRG flows of a UV-interacting scalar field theory

Speaker: Jobst Ziebell

presentation.pdf

09:30 → 10:00 Towards the characterization of wedge-local observables in integrable models with bound states

We discuss the structure of local observables in 1+1-dimensional quantum integrable models. An important advantage in these models is the existence of an "interacting Fock-space", generated by interacting creation and annihilation operators (so-called Zamolodchikov operators). The observables in question are (usually infinite) series in Zamolodchikov operators with certain functions ("form factors") as coefficients. However, locality of this form factor expansion is hard to establish as convergence of products of expansions is difficult to control. A solution to this problem can be the use of a wedge-local field, i.e., with a weaker localization. This can be expressed as a finite "expansion" in Zamolodchikov operators, taking a form similar to a free field. Making use of this intermediate object, local observables have been characterized in terms of infinite expansions in scalar models without bound states. We present a generalization of this approach to models with bound states
(e.g., the Bullough-Dodd or Z(N)-Ising model). In these models, the wedge-local field loses its simple "free field like" form due to an additional unbounded term with intricate domain properties. These complications increase in models with composite particles, e.g., the Z(4)-Ising model. Recent advances in this direction are presented.

Speaker: Karim Shedid

KarimShedid-TowardsWedgeLocalObservables-Slides.pdf

10:00 → 10:30 Semi-classical BMS-blocks from the Oscillator Construction

Speaker: Katharina Wölfl

Conformal Blocks with the Oscillator Construction_20210322.pdf

10:30 → 11:00 Break

11:00 → 12:00 Spacetime singularities and cosmic censorship I

Speaker: Håkan Andreasson

Physik-Combo-I-210322.pdf

12:00 → 12:15 Lecture Q&A

12:15 → 14:30 Break

14:30 → 15:30 Cosmology and Inflation I

Speaker: Enrico Pajer

Live Lectures PhD School.pdf

15:30 → 15:45 Lecture Q&A

15:45 → 16:15 Break

16:15 → 16:45 Temperature and entropy-area relation of quantum matter near spherically symmetric outer trapping horizons

Speaker: Fiona Kurpicz

16:45 → 17:15 A regularized perturbative treatment of BRST and Background Effective Action

Speaker: Dimitrios Gkiatas

Combo_Talk_Dimitrios_Gkiatas.pdf

Tuesday 23 March

09:00 → 09:30 Disc of dust: quasi-stationary routes to black holes in Einstein-Maxwell theory

Speaker: David Rumler

Rumler - disc of dust.pdf

09:30 → 10:00 Conservation laws and the Discontinuous Galerkin method

Speaker: Florian Atteneder

presentation.pdf

10:00 → 10:30 Hyperbolic formulations of GR

Speaker: Daniela Cors

10:30 → 11:00 Break

11:00 → 12:00 Spacetime singularities and cosmic censorship II

Speaker: Håkan Andreasson

Physik-Combo-II-210323s.pdf

12:00 → 12:15 Lecture Q&A

12:15 → 14:30 Break

14:30 → 15:30 Cosmology and Inflation II

Speaker: Enrico Pajer

Live Lectures PhD School 2.pdf

15:30 → 15:45 Lecture Q&A

15:45 → 16:15 Break

16:15 → 17:15 What happens at the end of Hawking's evaporation?

There are three distinct regions where quantum gravity becomes non-negligible in a black hole spacetime. I illustrate a number of indications we have about what happens in each of them, coming both from the classical Einstein equations and from loop quantum gravity. These point all to an interesting scenario: long living remnants stabilized by quantum gravity, formed by a large and slowly decreasing interior enclosed into a small anti-trapping horizon. Contrary to what too often stated, the scenario offers also a proof of principle that there is no tension between unitarity and the equivalence principle: the tension comes from postulating a version of holography which is too strong: a fad, for which there is no solid physical evidence.

Speaker: Carlo Rovelli

17:15 → 17:30 Lecture Q&A

Wednesday 24 March

09:00 → 09:30 Spin-foam models of Lorentzian space-time: Emerging geometry at the semiclassical limit

Speaker: José Simao

Talk_notetrad_v2.pdf

09:30 → 10:00 Chiral Spiral for finite number of flavors

Speaker: Michael Mandl

mandl_handout.pdf

10:00 → 10:30 Attenuation of energy relaxation in chiral one-dimensional quantum channels

Speaker: Stefan Georg Fischer

10:30 → 11:00 Break

11:00 → 12:00 Spacetime singularities and cosmic censorship III

Speaker: Håkan Andreasson

Physik-Combo-III.pdf

12:00 → 12:15 Lecture Q&A

12:15 → 13:30 Break

13:30 → 14:30 RTG fellow meeting / RTG PI meeting

14:30 → 15:30 Cosmology and Inflation III

Speaker: Enrico Pajer

Live Lectures PhD School.pdf

15:30 → 15:45 Lecture Q&A

15:45 → 16:15 Break

16:15 → 17:15 Combo Colloquium: "What have we learned so far in quantum gravity?"

The problem of quantum gravity is open because we do not have a preferred complete theory that has found direct empirical support. But there is a reliable theory of quantum gravity below the Planckian energy and there are consistent tentative quantum gravity theories; hence quantum theory and general relativity are not incompatible. Furthermore, there are recent empirical observations that disconfirm tentative theories, and there is also a concrete possibility to observe a quantum gravity phenomenon in the lab, in a not too distant future, hence research in quantum gravity is
connected to observations and experiments.

Speaker: Carlo Rovelli