59. Winter School of Theoretical Physics and third COST Action CA18108 Training School "Gravity -- Classical, Quantum and Phenomenology"

12 Feb 2023, 07:15 → 21 Feb 2023, 16:45 Europe/Warsaw

Pałac Wojanów, Poland

Welcome to the 59. Winter School of Theoretical Physics and third COST Action CA18108 Training School

"Gravity -- Classical, Quantum and Phenomenology"

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Videos of the lectures:

https://youtube.com/playlist?list=PL9Oo0bEL5LTJDgV2qI1iil1Lc_X-mThSN

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This COST Action CA18108 training school is held jointly with the 59th edition of the Winter School of Theoretical Physics. The event is organized by the Institute of Theoretical Physics of the University of Wroclaw, Poland.

The European COST Action CA18108 - “Quantum Gravity Phenomenology in the Multi-Messenger Approach”(https://qg-mm.unizar.es/), is an initiative funded by the COST Association (https://www.cost.eu/), whose goal is to investigate possible signatures predicted by quantum gravity models in the observation of different cosmic messengers, such as gamma rays, neutrinos, cosmic rays and gravitational waves.

The success of this endeavor requires the close collaboration of scientists from very different backgrounds, ranging from experimentalists specialized in data collection and analyses for specific cosmic messengers, to theorists working on different quantum gravity models.

A fundamental ingredient to make such cooperation effective is to share a common language and be familiar with the tools used by the different communities. This is where the role of this school comes in as fundamental: its goal is to start training a generation of young scientists in the interdisciplinary expertise on quantum gravity theories and models and on experimental and theoretical approaches to multi-messenger astroparticle physics.

As such, the different editions of the Training School will offer lectures from experts on different facets of the scientific gear the students will acquire, including data analysis and interpretation for individual sources, the creation and analysis of joint datasets of different cosmic messengers, the interplay between quantum gravity theory modeling and phenomenological predictions.  

The school is aimed at Master and PhD students, as well as early-career postdocs.

The school is generously subsidized from the state budget funds within the programme of Polish Ministry of Education and Science titled "Doskonała Nauka", project number DNK/SP/548521/2022, and by the COST Action CA18108. It is organized also under the auspices of the Polish Society on Relativity.

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Dates

December 31: Registration deadline

January 08: Confirmation of participation approval and of financial support

February 12: Arrival day and beginning of the school (in the afternoon)

February 21: Departure day (in the morning)

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Lectures

• Giovanni Amelino-Camelia:

         "Quantum gravity phenomenology at the dawn of multi-messenger astronomy"

• Sami Caroff:

        "Search for Lorentz Invariance Violation with time-lag on gamma-ray
         Cherenkov Telescope data : From the data to the time lag contraints"

• Luca Ciambelli:

         "Cornering quantum gravity"

• Andrea Maselli:

         "Astrophysical black holes: theory and observations"

• Emmanuel Saridakis:

         "Modified gravity theories"

• Benjamin Wandelt:

         "Cosmology: observations"
 

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Student talks

The schedule for the student talks can be found by clicking on the student presentation sessions of the timetables

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Telegram group for last-minute announcements: https://t.me/+Zm5TCJ3DkSYwMjc0

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Sunday 12 February

19:15 → 20:45 Dinner

Monday 13 February

08:00 → 08:45 Breakfast

08:45 → 09:00 Opening

09:00 → 11:00 Astrophysical black holes: theory and observations

he goal of these lectures is to introduce the students to the formalism of relativistic perturbation theory. We will study in particular the linear response of a BH to an external perturbation, and identify the various features of the emitted gravitational wave signals, focusing on the Quasi Normal Modes (QNMs), the black hole characteristic oscillation frequencies, and on their spectrum. We will investigate the connection between QNMs and null geodesics, and introduce different mathematical techniques used to compute their actual values. Finally, we will link QNMs to astrophysical observations, and study how they can be used to test pillars of Einstein theory, as the uniqueness of the Kerr metric.

Convener: Andrea Maselli

exercisesMaselli

• Equations_Zerilli_Ex3.nb
• Ex1.pdf
• Ex2.pdf
• Ex3.pdf

11:00 → 11:30 Coffee break

11:30 → 13:30 Astrophysical black holes: theory and observations

he goal of these lectures is to introduce the students to the formalism of relativistic perturbation theory. We will study in particular the linear response of a BH to an external perturbation, and identify the various features of the emitted gravitational wave signals, focusing on the Quasi Normal Modes (QNMs), the black hole characteristic oscillation frequencies, and on their spectrum. We will investigate the connection between QNMs and null geodesics, and introduce different mathematical techniques used to compute their actual values. Finally, we will link QNMs to astrophysical observations, and study how they can be used to test pillars of Einstein theory, as the uniqueness of the Kerr metric.

Convener: Andrea Maselli

exercisesMaselli

• Equations_Zerilli_Ex3.nb
• Ex1.pdf
• Ex2.pdf
• Ex3.pdf

13:30 → 15:00 Lunch

15:00 → 16:30 Discussion time

16:30 → 17:30 Students' talks

16:30 Probing gravitational theories via primordial black holes

One of the common prepositions in theoretical physics is that modified gravity theories capture quantum gravity corrections to general relativity at a phenomenological level. A recent new window to probe these corrections presented itself in the form of studying the scalar induced GWs which are produced by primordial black holes (PBHs) through second-order gravitational effects. In my talk, I shall present explicitly how one can perform this analysis in the context of R^2 modified theories of gravity and possibly even in the context of Loop Quantum Cosmology scenarios.

Speaker: Charalampos Tzerefos

1630Tzerefos (Poland).pdf

16:50 Coupling metric-affine gravity to a Higgs-like scalar field

General relativity (GR) exists in different formulations. They are equivalent in pure gravity but generically lead to distinct predictions once matter is included. After a brief overview of various versions of GR, we focus on metric-affine gravity, which avoids any assumption about the vanishing of curvature, torsion, or nonmetricity. We use it to construct an action of a scalar field coupled nonminimally to gravity. It encompasses as special cases numerous previously studied models. Eliminating nonpropagating degrees of freedom, we derive an equivalent theory in the metric formulation of GR. Finally, we give a brief outlook of implications for Higgs inflation.

Speaker: Claire Rigouzzo

1650-Rigouzzo.pdf

17:10 A generalization of Einstein’s quadrupole formula for radiated energy in de Sitter spacetime

We consider gravitational radiation produced by a time changing matter source in de Sitter spacetime. A Killing horizon is used as a generalization of the conformal boundary used in the radiation theory in Minkowski spacetime. We derived the expression for the energy of the radiation passing through the horizon. Our result takes the form of a generalized quadrupole formula expressed in terms of the mass and pressure quadrupole moments and is written explicitly up to the first order in $\sqrt{\Lambda}$. The zeroth order term recovers the famous Einstein’s quadrupole formula obtained for the perturbed Minkowski spacetime, whereas the first order term is a new correction.

Speaker: Denis Dobkowski-Ryłko

1710-d_dobkowski_rylko.pdf

17:30 → 18:00 Coffee break

18:00 → 19:00 Students' talks

18:00 Massless Dirac Perturbations in a Consistent Model of Loop Quantum Gravity Black Holes: Quasinormal Modes and Greybody factor

We consider perturbations of the massless Dirac field in the background of a black hole solution found by Bodendorfer, Mele and Münch (BMM), using a polymerization technique that furnishes contributions inspired by loop quantum gravity. Using the 6th order WKB method, we analyzed its quasinormal modes for several modes, multipole numbers and the two classes of BMM black holes. We also considered the potential that governs these perturbations to analyze the bound on the greybody factor due the emission rates of particles. As results, we found that the loop quantum gravity parameters are responsible for raising the potential and the real and imaginary parts of the quasinormal frequencies and decrease the bound on the greybody factor for the two classes of black holes with more more prominent effects for the de-amplification case, which is compatible with previous analyses done for other fields.

Speaker: Saulo Soares de Albuquerque Filho

1800-Saulo_Phen_Quant_Grav_School_More_Summarized_Version.pdf

18:20 Fundamental decoherence from quantum spacetime

Speaker: Vittorio D'Esposito

1820-Vittorio_D'Esposito.pdf

19:15 → 20:45 Dinner

Tuesday 14 February

08:00 → 08:45 Breakfast

08:45 → 09:00 Announcements

09:00 → 11:00 Astrophysical black holes: theory and observations

he goal of these lectures is to introduce the students to the formalism of relativistic perturbation theory. We will study in particular the linear response of a BH to an external perturbation, and identify the various features of the emitted gravitational wave signals, focusing on the Quasi Normal Modes (QNMs), the black hole characteristic oscillation frequencies, and on their spectrum. We will investigate the connection between QNMs and null geodesics, and introduce different mathematical techniques used to compute their actual values. Finally, we will link QNMs to astrophysical observations, and study how they can be used to test pillars of Einstein theory, as the uniqueness of the Kerr metric.

Convener: Andrea Maselli

exercisesMaselli

• Equations_Zerilli_Ex3.nb
• Ex1.pdf
• Ex2.pdf
• Ex3.pdf

11:00 → 11:30 Coffee break

11:30 → 13:30 Students' talks

11:30 Determinism at a black hole singularity

Speaker: Martina Adamo

1-Admo-MARTINA_ADAMO (1).pdf

11:50 Quantum correction to black hole entropy

I will discuss the semiclassical brick wall method of calculating the entropy of black holes. The brick wall is based on the WKB approximation and it can be used to calculate black hole entropy's corrections due to, e.g., the inclusion of noncommutative geometry into Einstein's equations.

Speaker: Filip Požar

2-Filip_Pozar.pdf

12:10 Entanglement entropy and the emergence of an arrow of time in the early universe

Roger Penrose's Weyl curvature hypothesis can be extended to the quantum regime, where 'past singularities' have to be replaced by 'regions of small enough scale factors' in the configuration space of the wave function of the universe. At a fundamental level the justification for the quantum version of the Weyl Curvature hypothesis is expected to come from a full quantum theory of gravity : quantum geometrodynamics. Here we study a toy model of the universe (for a small scale factor, i.e. early universe) which has two scalar fields. We calculate the linear (entanglement) entropy which increases with the scale factor and hence the semi-classical time. This forms the basis of an arrow of time in the universe and can help understand the origin of irreversibility in our universe.

Speaker: Mritunjay Tyagi

3-Tyagi_Mritunjay _COST_WINTER_SCHOOL.pdf

12:30 Rainbow Oppenheimer-Snyder collapse and the entanglement entropy production

I derive a new model of black-to-white hole transition - the classical Oppenheimer-Snyder dust ball interior is modified with Loop Quantum Cosmology dynamics. I consider the rainbow metric approach for both pure dust ball collapse and the similar scenario accounting for scalar field perturbations. The collapsing matter bounces and reemerges in a new universe. Exterior geometry is extracted as well as the global causal structure of the process. I study entanglement entropy production to verify whether the black hole information paradox exists within the model.

Speaker: Michał Bobula

4-MichalBobulaWinterSchool.pdf

12:50 The time problem and primordial perturbations

The problem of time in physics arises from the conceptual discrepancies between non-relativistic and relativistic time.
The principle of general covariance in general relativity gives us the freedom to choose an arbitrary clock for our theory. In quantum mechanics, however, different choices of internal time variables are known to produce unitarily inequivalent quantum models.
In my presentation I will propose a fully analytical model of primordial gravitational waves propagating in a Friedman-Lema\^{i}tre-Robinson-Walker background with different clocks to study what are (if any) the dynamical predictions of quantum gravity models for large classical universes, which do not depend on the employed time variable.
Solving the Hamiltonian constraint of the model and fixing the internal time variable prior to quantization, we are able to study all the existing clocks and quantize them in a way that ensures a fixed ‘operator ordering’.
Hence, any quantum ambiguity found is safely ascribed to the different choice of clock.

Speaker: Alice Boldrin

5-Boldrin-Alice-presentation2023.pdf

13:10 Prescriptions and analytic control over quantum dynamics in loop quantum cosmology

Ambiguities of the so-called Thiemann regularization in Loop Quantum Cosmology lead to freedom in how to construct a particular quantization prescription, which in turn may significantly affect the mathematical structure of the quantum model and its dynamical predictions. Out of several prescriptions presented in the literature I will focus on one showing somewhat counterintuitive properties, often referred as mLQC-II. Its mathematical structure will be discussed in detail. It will be further used as an example for testing a variant of a semiclassical treatment that allows to analytically probe the dynamics of LQC systems with high order quantum corrections and with good control of the approximations for a wide variety of LQC/geometrodynamics models. This method will be in particular used to find (in the approximation of macroscopic universe) the quantum trajectory of the volume as analytic function of the internal clock and the so called central moments of the constants of motion.

Speaker: Maciej Kowalczyk

6-Kowalczyk-Wojanów23-MK.pdf

13:30 → 15:00 Lunch

15:00 → 19:15 free time

19:15 → 20:45 Dinner

Wednesday 15 February

08:00 → 08:45 Breakfast

08:45 → 09:00 Announcements

09:00 → 11:00 Astrophysical black holes: theory and observations

he goal of these lectures is to introduce the students to the formalism of relativistic perturbation theory. We will study in particular the linear response of a BH to an external perturbation, and identify the various features of the emitted gravitational wave signals, focusing on the Quasi Normal Modes (QNMs), the black hole characteristic oscillation frequencies, and on their spectrum. We will investigate the connection between QNMs and null geodesics, and introduce different mathematical techniques used to compute their actual values. Finally, we will link QNMs to astrophysical observations, and study how they can be used to test pillars of Einstein theory, as the uniqueness of the Kerr metric.

Convener: Andrea Maselli

exercisesMaselli

• Equations_Zerilli_Ex3.nb
• Ex1.pdf
• Ex2.pdf
• Ex3.pdf

11:00 → 11:30 Coffee break

11:30 → 13:30 Astrophysical black holes: theory and observations (tutorials)

Convener: Andrea Maselli

MaselliExercises2

• Mathematica_1.zip
• Mathematica_2.zip
• Mathematica_3.zip
• Wrocwlaw_2023.pdf

13:30 → 15:00 Lunch

15:00 → 16:00 Students' talks

15:00 Quasinormal modes in teleparallel gravity

Small perturbations of spherical symmetric Schwarzschild backgrounds in General Relativity have been already discussed since 1957 by Regge and Wheeler [1] and the quasinormal frequencies of relativistic stars and black holes that emit gravitational waves have been investigated by Nollert [2], Kokkotas and Schmidt [3] as well since 1999. Considering the quite recent detection of gravitational waves in 2015 [4], it is interesting to go back to the topic of quasinormal modes. General Relativity -though a quite successful theory of gravity- is not able to address several issues like the nature of dark matter and dark energy and the accelerated expansion of the universe. Modified theories of gravity appear to be better candidates. We consider in particular the metric teleparallel theory where the gravitational field is not mediated by the curvature as in GR but instead by the torsion [5]. We discuss how we approach the topic of quasinormal modes in this theory following the recent master thesis work by Asuküla [6]. [1] T. Regge and J. A. Wheeler, "Stability of a Schwarzschild Singularity", Phys. Rev. 108, 1063–1069 (1957) [2] K. D. Kokkotas and B. G. Schmidt, "Quasi-Normal Modes of Stars and Black Holes", Living Reviews in Relativity 2 (1999) [3] H.-P. Nollert, "Quasinormal modes: the characteristic ’sound’ of black holes and neutron stars", Classical and Quantum Gravity 16, R159–R216 (1999) [4] B. P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration), "Observation of Gravitational Waves from a Binary Black Hole Merger", Phys. Rev. Lett. 116, 061102 (2016) [5] K. Hayashi and T. Shirafuji, "New general relativity", Phys. Rev. D 19, 3524–3553 (1979) [6] H. Asuküla, "Quasinormal modes of Schwarzschild black holes in 1-parameter New General Relativity" (2021) (Master Thesis, Institute of Physics, University of Tartu)

Speaker: Vasilki Karanasou

2-VKaranasou-Winter school.pdf

15:20 Energy and entropy in the Geometrical Trinity of gravity

All energy is gravitational energy. That is the consequence of the equivalence principle, according to which gravity is the universal interaction. The physical charges of this interaction have remained undisclosed, but the Advent of the Geometrical Trinity opened a new approach to this foundational problem. Here it is shown to provide a background-independent unification of the previous, noncovariant approaches of Bergmann-Thomson, Cooperstock, Einstein, von Freud, Landau-Lifshitz, Papapetrou and Weinberg. First, the Noether currents are derived for a generic Palatini theory of gravity coupled with generic matter fields, and then the canonical i.e. the unique charges are robustly derived and analysed, particularly in the metric teleparallel and the symmetric teleparallel versions of General Relativity. These results, and their application to black holes and gravitational waves, are new.

Speaker: Débora Aguiar Gomes

1-Cost_Débora.pdf

15:40 5D Chern-Simons Gravity, RS Braneworld and Holography

Five-dimensional Chern-Simons gravity is very interesting theory that allows for a space-time to have both nonzero curvature and torsion , yet it is defined in one higher number of dimensions than we currently experimentally observe. In this talk, we will review some aspects of five-dimensional Chern-Simons gravity with AdS gauge group. Using holography as our guiding tool, we will write down the equations of a gravity (coupled with a cutoff CFT) on the Randall-Sundrum brane, thus establishing a connection with four-dimensional physics. We then construct some explicit but simple solutions of those equations.

Speaker: Dusan Djordjevic

3-DusanDjordjevic (1).pdf

16:00 → 16:30 Coffee break

16:30 → 17:30 Students' talks

16:30 Quantum Euler angles and agency-dependent spacetime

Speaker: Domenico Frattulillo

4-Domenico_Frattulillo_4.pdf

16:50 θ-angle physics of two color QCD: fixed baryon charge and near conformal dynamics

Speaker: Alessandra D'Alise

5-ALESSANDRA_D'ALISE.pdf

17:10 Solving constraints using quantum computers

One of the central difficulties in the quantization of the gravitational interactions is that they are described by a set of constraints. We propose and investigate a new methods of solving constraints equations, which employ a variational quantum computing approach and projection approach, possible to implement on quantum computers. For the purpose of testing our methods, both an emulator of a quantum computer and the IBM superconducting quantum computer have been used.

Speaker: Grzegorz Czelusta

6-Czelusta.pdf

17:30 → 19:00 Discussion time

19:15 → 20:45 Dinner

Thursday 16 February

08:00 → 08:45 Breakfast

08:45 → 09:00 Announcements

09:00 → 11:00 Modified gravity theories

Newtonian gravity was a very successful gravitational theory in agreement with all observations and experiments up to late 19th century, where the enhancement of observational/experimental precision, as well as the improvement of theoretical calculations, led to tensions, which in turn led to general relativity. General relativity is a very successful gravitational theory in agreement with all observations and experiments, however we may have entered the era where the enhancement of observational/experimental precision, as well as the improvement of theoretical calculations, leads to tensions, whose solution may require to construct a modified theory of gravity. Modified gravity must have general relativity as a particular limit, in the same way that general relativity has Newtonian gravity as a particular limit.

We briefly review general relativity, mentioning its (arbitrary or guided by experiments and observations) assumptions and considerations. Then we abandon them, resulting to various modified theories of gravity, including f(R) and f(G) gravity, scalar-tensor and Horndeski theories, massive gravity, torsional theories, f(T) and teleparallel Horndeski gravity, etc, mentioning their possible smoking guns in cosmological, black-hole, as well as gravitational-wave observations.

Convener: Emmanuel Saridakis (National Technical University of Athens & National Observatory of Athens)

11:00 → 11:30 Coffee break

11:30 → 13:30 Modified gravity theories

Newtonian gravity was a very successful gravitational theory in agreement with all observations and experiments up to late 19th century, where the enhancement of observational/experimental precision, as well as the improvement of theoretical calculations, led to tensions, which in turn led to general relativity. General relativity is a very successful gravitational theory in agreement with all observations and experiments, however we may have entered the era where the enhancement of observational/experimental precision, as well as the improvement of theoretical calculations, leads to tensions, whose solution may require to construct a modified theory of gravity. Modified gravity must have general relativity as a particular limit, in the same way that general relativity has Newtonian gravity as a particular limit.

We briefly review general relativity, mentioning its (arbitrary or guided by experiments and observations) assumptions and considerations. Then we abandon them, resulting to various modified theories of gravity, including f(R) and f(G) gravity, scalar-tensor and Horndeski theories, massive gravity, torsional theories, f(T) and teleparallel Horndeski gravity, etc, mentioning their possible smoking guns in cosmological, black-hole, as well as gravitational-wave observations.

Convener: Emmanuel Saridakis (National Technical University of Athens & National Observatory of Athens)

13:30 → 15:00 Lunch

15:00 → 16:00 Cosmology: observations

What is observable in cosmology from a theorist’s perspective. The state and prospects of observational data in cosmology. How to connect cosmological theory with data, using some notions of statistics, machine learning, and Bayesian analysis as applied to cosmology.

Convener: Benjamin Wandelt

16:00 → 16:30 Coffee break

16:30 → 17:30 Cosmology: observations

What is observable in cosmology from a theorist’s perspective. The state and prospects of observational data in cosmology. How to connect cosmological theory with data, using some notions of statistics, machine learning, and Bayesian analysis as applied to cosmology.

Convener: Benjamin Wandelt

17:30 → 19:00 Discussion time

19:15 → 20:45 Dinner

Friday 17 February

08:00 → 08:45 Breakfast

08:45 → 09:00 Announcements

09:00 → 11:00 Cosmology: observations

What is observable in cosmology from a theorist’s perspective. The state and prospects of observational data in cosmology. How to connect cosmological theory with data, using some notions of statistics, machine learning, and Bayesian analysis as applied to cosmology.

Convener: Benjamin Wandelt

11:00 → 11:30 Coffee break

11:30 → 13:30 Cosmology: observations

What is observable in cosmology from a theorist’s perspective. The state and prospects of observational data in cosmology. How to connect cosmological theory with data, using some notions of statistics, machine learning, and Bayesian analysis as applied to cosmology.

Convener: Benjamin Wandelt

13:30 → 15:00 Lunch

15:00 → 16:00 Modified gravity theories

Newtonian gravity was a very successful gravitational theory in agreement with all observations and experiments up to late 19th century, where the enhancement of observational/experimental precision, as well as the improvement of theoretical calculations, led to tensions, which in turn led to general relativity. General relativity is a very successful gravitational theory in agreement with all observations and experiments, however we may have entered the era where the enhancement of observational/experimental precision, as well as the improvement of theoretical calculations, leads to tensions, whose solution may require to construct a modified theory of gravity. Modified gravity must have general relativity as a particular limit, in the same way that general relativity has Newtonian gravity as a particular limit.

We briefly review general relativity, mentioning its (arbitrary or guided by experiments and observations) assumptions and considerations. Then we abandon them, resulting to various modified theories of gravity, including f(R) and f(G) gravity, scalar-tensor and Horndeski theories, massive gravity, torsional theories, f(T) and teleparallel Horndeski gravity, etc, mentioning their possible smoking guns in cosmological, black-hole, as well as gravitational-wave observations.

Convener: Emmanuel Saridakis (National Technical University of Athens & National Observatory of Athens)

16:00 → 16:30 Coffee break

16:30 → 17:30 Modified gravity theories

Newtonian gravity was a very successful gravitational theory in agreement with all observations and experiments up to late 19th century, where the enhancement of observational/experimental precision, as well as the improvement of theoretical calculations, led to tensions, which in turn led to general relativity. General relativity is a very successful gravitational theory in agreement with all observations and experiments, however we may have entered the era where the enhancement of observational/experimental precision, as well as the improvement of theoretical calculations, leads to tensions, whose solution may require to construct a modified theory of gravity. Modified gravity must have general relativity as a particular limit, in the same way that general relativity has Newtonian gravity as a particular limit.

We briefly review general relativity, mentioning its (arbitrary or guided by experiments and observations) assumptions and considerations. Then we abandon them, resulting to various modified theories of gravity, including f(R) and f(G) gravity, scalar-tensor and Horndeski theories, massive gravity, torsional theories, f(T) and teleparallel Horndeski gravity, etc, mentioning their possible smoking guns in cosmological, black-hole, as well as gravitational-wave observations.

Convener: Emmanuel Saridakis (National Technical University of Athens & National Observatory of Athens)

17:30 → 19:00 Discussion time

19:15 → 20:45 Dinner

Saturday 18 February

08:00 → 08:45 Breakfast

08:45 → 09:00 Announcements

09:00 → 11:00 Search for Lorentz Invariance Violation with time-lag on gamma-ray Cherenkov Telescope data : From the data to the time lag constraints

This lecture will be dedicated to present the full work needed form the Cherenkov Telescope data to the analysis of LIV induced time-lag. This lecture will start with a presentation of gamma ray data and their production, and how they are analysed to produce high level results. We will work in a concrete way in real open data of the HESS cherenkov Telescope in order to assess the temporal and energetic distribution of an AGN flare. This first work will lead us to the next step, to extract constraints on an energy dependent time-lag from these real data. We will learn first how to produce Toy Monte Carlo data in order to test in safe environments time lag assessment, and in a second step work with real data.

Convener: Sami Caroff

tutorial_LIV.pdf

11:00 → 11:30 Coffee break

11:30 → 13:30 Search for Lorentz Invariance Violation with time-lag on gamma-ray Cherenkov Telescope data : From the data to the time lag constraints

This lecture will be dedicated to present the full work needed form the Cherenkov Telescope data to the analysis of LIV induced time-lag. This lecture will start with a presentation of gamma ray data and their production, and how they are analysed to produce high level results. We will work in a concrete way in real open data of the HESS cherenkov Telescope in order to assess the temporal and energetic distribution of an AGN flare. This first work will lead us to the next step, to extract constraints on an energy dependent time-lag from these real data. We will learn first how to produce Toy Monte Carlo data in order to test in safe environments time lag assessment, and in a second step work with real data.

Convener: Sami Caroff

tutorial_LIV.pdf

13:30 → 15:00 Lunch

15:00 → 16:00 Students' talks

15:00 Study of Universe Transparency in an LIV Framework

Speaker: Filip Rescic

1-Reščić-LIV_FR.pdf

15:20 LIV search with the Crab Pulsar

Speaker: Anna Campoy Ordaz

2-CAMPOY_ORDAZ-LIV_search_with_the_Crab_Pulsar_ANNA_CAMPOY_ORDAZ.pdf

15:40 Atom interferometry and small-scale tests of general relativity

Since the first appearance of general relativity in 1916, various experiments have been conducted to test the theory. Due to the weakness of the interactions involved, all of the documented tests were carried out in a gravitational field generated by objects of an astronomical scale. We explain what atom interferometers are and how they can be used to test general relativity in the small-scale regime (M. Myszkowski, General Relativity and Gravitation, Vol.54, 2022).

Speaker: Mikolaj Myszkowski

3-Myszkowski-Atom interferometry and small-scale tests of general relativity.pdf

16:00 → 16:30 Coffee break

16:30 → 17:50 Students' talks

16:30 Noncommutative gravity using twists

The formalism of Hopf algebras and Drinfeld twist are introduced along with noncommutative star-product. Star-product is then generalised to differential-geometric structures: vector fields, forms, connection,... Perturbations of Schwarzschild spacetime are then investigated as a practical example. A brief overview of the standard BH perturbation theory can also be given (depending on the duration of the talk): first order metric correction, decomposition into spherical tensor harmonics, axial and polar modes, Regge-Wheeler gauge and potential.

Speaker: Nikola Herceg

4-Herceg-Noncommutative gravity using twists.pdf

16:50 k-Braided noncommutative field theory

Speaker: Maria Grazia Di Luca

5-Maria Grazia Di Luca-k-Braided non-commutative field theory.pdf

17:10 Total momentum and other Noether charges for particles interacting in a quantum spacetime

Speaker: Giuseppe Fabiano

6-giuseppe fabiano .pdf

17:30 κ-deformed complex fields, (discrete) symmetries, and charges

In this talk I will briefly describe a construction of a κ-deformed complex scalar field theory, while at the same time shedding light on the behaviour of discrete and continuous symmetries in this formalism. This in turn will open the way to the study of the application of this formalism to actual physical processes. I will then conclude with some comments and prospects for the future.

Speaker: Andrea Bevilacqua

7-AndreaBevilacquaPresentation.pdf

17:50 → 19:00 Discussion time

19:15 → 20:45 Dinner

Sunday 19 February

08:00 → 08:45 Breakfast

08:45 → 09:00 Announcements

09:00 → 11:00 Cornering quantum gravity

These lectures aim at giving a freshen perspective on classical gravitational theories as a starting point for quantum physics. We review the covariant phase space formalism and Noether's theorems, insisting in particular on gauge symmetries. In the presence of boundaries, part of the otherwise pure gauge symmetries becomes physical. Such symmetries are called asymptotic (to the boundary) symmetries, and are the crucial ingredient of these lectures. We show how they are the underlying symmetry structure of memory effects in electromagnetism and gravity, and how they lead to the soft theorems. This allows us to enunciate the infrared triangle relating memories, symmetries, and soft theorems. We then formulate the corner proposal, which is a novel approach to quantum gravity, based again on these symmetries. We first prove how a careful understanding of embeddings provides a canonical gravitational Poisson bracket for us. Secondly, we comment on how the corner proposal helps us focussing on classical features that are more suitable for quantization. We conclude with a list of future steps to be made to shed new light on quantum gravity. To elucidate and familiarize with the important results, exercises are proposed and solved throughout the lectures.

Convener: Luca Ciambelli

11:00 → 11:30 Coffee break

11:30 → 13:30 Quantum gravity phenomenology at the dawn of multi-messenger astronomy

Convener: Giovanni Amelino-Camelia

13:30 → 15:00 Lunch

15:00 → 16:00 Cornering quantum gravity

These lectures aim at giving a freshen perspective on classical gravitational theories as a starting point for quantum physics. We review the covariant phase space formalism and Noether's theorems, insisting in particular on gauge symmetries. In the presence of boundaries, part of the otherwise pure gauge symmetries becomes physical. Such symmetries are called asymptotic (to the boundary) symmetries, and are the crucial ingredient of these lectures. We show how they are the underlying symmetry structure of memory effects in electromagnetism and gravity, and how they lead to the soft theorems. This allows us to enunciate the infrared triangle relating memories, symmetries, and soft theorems. We then formulate the corner proposal, which is a novel approach to quantum gravity, based again on these symmetries. We first prove how a careful understanding of embeddings provides a canonical gravitational Poisson bracket for us. Secondly, we comment on how the corner proposal helps us focussing on classical features that are more suitable for quantization. We conclude with a list of future steps to be made to shed new light on quantum gravity. To elucidate and familiarize with the important results, exercises are proposed and solved throughout the lectures.

Convener: Luca Ciambelli

16:00 → 16:30 Coffee break

16:30 → 18:30 Search for Lorentz Invariance Violation with time-lag on gamma-ray Cherenkov Telescope data : From the data to the time lag constraints

This lecture will be dedicated to present the full work needed form the Cherenkov Telescope data to the analysis of LIV induced time-lag. This lecture will start with a presentation of gamma ray data and their production, and how they are analysed to produce high level results. We will work in a concrete way in real open data of the HESS cherenkov Telescope in order to assess the temporal and energetic distribution of an AGN flare. This first work will lead us to the next step, to extract constraints on an energy dependent time-lag from these real data. We will learn first how to produce Toy Monte Carlo data in order to test in safe environments time lag assessment, and in a second step work with real data.

Convener: Sami Caroff

tutorial_LIV.pdf

19:15 → 20:45 Dinner

Monday 20 February

08:00 → 08:45 Breakfast

08:45 → 09:00 Announcements

09:00 → 11:00 Cornering quantum gravity

These lectures aim at giving a freshen perspective on classical gravitational theories as a starting point for quantum physics. We review the covariant phase space formalism and Noether's theorems, insisting in particular on gauge symmetries. In the presence of boundaries, part of the otherwise pure gauge symmetries becomes physical. Such symmetries are called asymptotic (to the boundary) symmetries, and are the crucial ingredient of these lectures. We show how they are the underlying symmetry structure of memory effects in electromagnetism and gravity, and how they lead to the soft theorems. This allows us to enunciate the infrared triangle relating memories, symmetries, and soft theorems. We then formulate the corner proposal, which is a novel approach to quantum gravity, based again on these symmetries. We first prove how a careful understanding of embeddings provides a canonical gravitational Poisson bracket for us. Secondly, we comment on how the corner proposal helps us focussing on classical features that are more suitable for quantization. We conclude with a list of future steps to be made to shed new light on quantum gravity. To elucidate and familiarize with the important results, exercises are proposed and solved throughout the lectures.

Convener: Luca Ciambelli

11:00 → 11:30 Coffee break

11:30 → 13:30 Quantum gravity phenomenology at the dawn of multi-messenger astronomy

Convener: Giovanni Amelino-Camelia

13:30 → 15:00 Lunch

15:00 → 16:00 Cornering quantum gravity

These lectures aim at giving a freshen perspective on classical gravitational theories as a starting point for quantum physics. We review the covariant phase space formalism and Noether's theorems, insisting in particular on gauge symmetries. In the presence of boundaries, part of the otherwise pure gauge symmetries becomes physical. Such symmetries are called asymptotic (to the boundary) symmetries, and are the crucial ingredient of these lectures. We show how they are the underlying symmetry structure of memory effects in electromagnetism and gravity, and how they lead to the soft theorems. This allows us to enunciate the infrared triangle relating memories, symmetries, and soft theorems. We then formulate the corner proposal, which is a novel approach to quantum gravity, based again on these symmetries. We first prove how a careful understanding of embeddings provides a canonical gravitational Poisson bracket for us. Secondly, we comment on how the corner proposal helps us focussing on classical features that are more suitable for quantization. We conclude with a list of future steps to be made to shed new light on quantum gravity. To elucidate and familiarize with the important results, exercises are proposed and solved throughout the lectures.

Convener: Luca Ciambelli

16:00 → 16:30 Coffee break

16:30 → 18:30 Quantum gravity phenomenology at the dawn of multi-messenger astronomy

Convener: Giovanni Amelino-Camelia

19:15 → 20:45 Dinner

Tuesday 21 February

08:00 → 08:45 Breakfast