[hep-th] QG-AA: Giulia Gubitosi and Nikolaos Mavromatos on Friday, November 19 (fwd)

[Marko Vojinovic]

---------- Forwarded message ----------
Date: Sat, 13 Nov 2021 10:22:54 -0500
From: Sebastian Fischetti <fischetti at physics.mcgill.ca>
To: undisclosed-recipients:  ;
Subject: QG-AA: Giulia Gubitosi and Nikolaos Mavromatos on Friday, November 19


Hi everyone,

This is an advertisement for the next event in the QG-AA series, which will take place on Friday, November 19 at 18:00 CET (12:00 EST, 09:00 PST).  We're happy to have Giulia Gubitosi
(University of Naples) and Nikolaos Mavromatos (Natl. Tech. U. Athens, Greece and King's College Lodnon, UK) giving back-to-back talks:

Giulia Gubitosi: Planck-scale deformations of relativistic symmetries

Nikolaos Mavromatos: Anomalies and Torsion in Quantum Gravity and Lorentz Violation in the Universe

In search for a consistent theory of Quantum Gravity, I explore the possibility that Riemannian geometry might be abandoned, at the expense of introducing  torsion as a fundamental
quantum field. In string inspired theories, such a quantum torsion is linked to spin-one antisymmetric-tensor fields in the massless string gravitational multiplet, which in
(3+1)-dimensions, after extra-dimensional compactification, corresponds to a fully dynamical massless pseudoscalar (axion-like) field. The latter can couple to gravitational anomalies
in a way consistent with general covariance. In other settings, such as Loop Quantum Gravity, these axions may be thought of as somewhat analogous to field theoretic extensions of the
Barbero-Immirzi parameter, which accompany torsional topological invariants in the corresponding effective gravitational actions. 
In such modified theories of gravity, which could be viewed as effective low-energy theories of mathematically consistent quantum gravity models, including, but also going beyond,
string theory, there are solutions for the axion background field which violate spontaneously Lorentz symmetry, as a result of condensation of gravitational anomalies induced by
primordial gravitational waves. The low-energy theory with matter resembles then the Standard Model Extension (SME) with terms that Violate Lorentz (LV) and CPT symmetries (CPTV). Apart
from theoretical considerations, the talk will also explore the phenomenology of the resulting cosmological models, paying particular attention to demonstrating  a link with a
running-vacuum-model inflationary cosmology, the emergence of matter antimatter asymmetry as a result of the aforesaid LV and CPTV, and the connection of the torsion-induced axion field
to dark matter, upon appropriate mass generation at post inflationary epochs.

We hope to see you there!

https://uni-jena-de.zoom.us/j/69556470634

Meeting ID: 695 5647 0634
Passcode: QG-AA

Best,

Lisa, Sebastian F, Sebastian S, and Aaron