Presentations

If you are interested in giving a short (5-minute) presentation, please send a title and a short abstract (2-3 lines)  to Konstantinos Siampos ksiampos@auth.gr before June 3rd.

Speakes include

Evangelos Afxonidis – Slides

Title: Fractons and dipole symmetry breaking

Abstract: Fractons are limited mobility excitations appearing in dipole-conserving models. I will introduce quantum field theories for monopole and dipole charges, showing via large-N techniques that the effective action includes an immobile fractonic Nambu-Goldstone mode.

Naveena Kumara Athithamoole – Slides

Title: Dynamics of Gravitational Perturbations in Noncommutative Geometry

Abstract: This study investigates the dynamics of gravitational perturbations within the framework of Hopf algebra and noncommutative differential geometry. By focusing on a semi-Killing Drinfeld twist and a novel noncommutative Einstein equation, we analyze the polar gravitational perturbations on a noncommutative Schwarzschild background.

Vasil Avramov – Slides

Title: Various aspects of complexity of oscillators in a magnetic field

Abstract: The focus of the talk is on the notion of Nielsen complexity, which quantifies the closeness between two quantum states. We examine results for the quantum complexity of an harmonic oscillator in an external magnetic field and a thermofield double state constructed from the same system. We find several important limits and investigate the effects of the magnetic field on complexity.

Ertuğrul Ekiz – Slides

Title: Electric Carrollian Field Theories

Abstract: In this presentation, we will start with what is meant by Electric Carrollian Sector or Magnetic Carrollian Sector. Then, we discuss several important point of the Carrollian Field Theories. After reviewing Electric Carrollian Scalar Fields, we will discuss possible Electric Carrollian Fermion structure and their difference with Relativistic Fermions.

David Sola Gil – Slides

Title: Strong Cosmic Censorship in Kerr-Newman-de Sitter

Abstract: Christodoulou’s version of Strong Cosmic Censorship (SCC) seeks to restore predictability in General Relativity. This conjecture has been classically shown to be respected by Kerr de-Sitter black holes and violated by near-extremal Reissner-Nordström-de Sitter black holes. We will review SCC in the interpolating spacetime: Kerr-Newman-de Sitter, as studied in https://arxiv.org/pdf/2404.03724.

Antonios Kalogirou – Slides

Title: Ising Cosmology

Abstract: We propose that the deviation of the scalar spectrum index n_S of scalar fluctuations from unity may be controlled almost entirely by the critical exponent η of the d=3 Ising model. Furthermore, we compute the thermal propagators of the scalar field and propose that non-trivial thermal effects as seen by an ‘out’ observer can be encoded by η which fixes completely a number of cosmological observables.

Leonidas Karageorgos – Slides

Title: Renormalization of 2pt-function of Energy Momentum Tensor & RG flows.

Abstract: In this short presentation, I will discuss our research in progress, on renormalization issues concerning the two-point function of the Energy-Momentum Tensor for a Quantum Field Theory (QFT) in the vicinity of an interacting fixed point.

Stylianos Kastrinakis – Slides

Title: Conformal transformations on a graph and the associated metric

Abstract: A brief presentation will be given of the key points of the paper under publication “Graph theoretical approach to conformal correlators” by professor Nikos Irges and Stylianos Kastrinakis, namely the construction of a conformally covariant metric on a weighted graph, how the correlator of N scalar operators can be expressed as the determinant of this metric and the metric’s possible role in constraining conformal data.

Tatiana Mihaescu – Slides

Title: Entanglement and steering in Gaussian quantum states

Abstract: In this presentation I will engage with the topic of quantum correlations, such as entanglement and steering, in Gaussian quantum states. This type of continuous variable systems are most commonly encountered in quantum optics experiments, while also being applicable to quantum information tasks.

Theodoros Nakas – Slides

Title: Black-hole solutions with primary scalar hair

Abstract: We present explicit black holes endowed with primary scalar hair within the shift-symmetric subclass of Beyond Horndeski theories. We observe that when the scalar hair is close to zero, the solutions closely resemble the Schwarzschild spacetime, while as the scalar hair increases, the metric solutions gradually depart from General Relativity. Notably, for a particular relation between mass and scalar hair, the central singularity completely disappears, resulting in the formation of regular black holes or solitons. This talk is based on the paper https://inspirehep.net/literature/2712204

Gabriele Pisacane – Slides

Title: Neutron interferometry to probe the Dark sector of the universe

Abstract: Dark matter is one of the mysteries of modern physics. There are many candidates for its explanation, from micro black holes to axions. In this work we develop a possible method to analyze one of these candidates, the mirror matter, via geometric invariants.

Shanmugapriya Prakasam – Slides

Title: Supersymmetric index for small black holes

Abstract: The macroscopic index computed in accordance with recently developed techniques at the two derivative level does not produce the desired matching with the well known microscopic counting for small black holes. In a subspace of the horizon of the black hole where the solution is singular, higher derivative corrections become important. A corrected macroscopic index including these higher derivative contributions produces the known microscopic results up to an overall numerical constant.

Filip Požar – Slides

Title: Twisted Hopf algebra modules are also twisted

Abstract: I will sketch a short proof of the fact that Drinfeld Twisted Hopf algebra’s modules can be obtained from the “untwisted” Hopf algebra’s modules by twisting them with the same Drinfeld element. This applies to the modules of spacetime functions, tensor algebra, vector fields etc.

Jonas Rongen – Whiteboard

Title: (Boost-Agnostic) Hydrodynamics

Abstract: Hydrodynamics can be understood as an effective field theoretical description of interacting systems close to thermal equilibrium in the long-wavelength limit. The dynamics of these systems are governed by the conservation of energy and momentum, and possibly a set of U(1) charge conservation laws. I will give a brief introduction to hydrodynamics in the absence of boost symmetry and its relation to holography.

Raoul Serao – Slides

Title: On the quantumness of gravity

Abstract: I will illustrate the role that entanglement can have in understanding one of the big open question in theoretical physics: quantum gravity. I will analyse the rising of a gravitational induced entanglement and the role of the decoherence in determining a minimum distance.

Dionysios – Stylianos Stefas – Slides

Title: Formulation of Gravity as a Gauge Theory on Covariant Noncommutative (Fuzzy) Spaces.

Abstract: This presentation explores the formulation of gravity as a gauge theory on covariant noncommutative (fuzzy) spaces. By extending the isometry group and employing a gauge theoretic approach an action is developed which, after a spontaneous symmetry breaking, provides a framework for noncommutative gravity.

Marko Stojanovic – Slides

Title: Constant roll inflation with tachyon field in the holographic RSII cosmology

Abstract: We consider a constant-roll inflation scenario, where the second slow-roll parameter remains constant. The scenario, when inflation is driven by a tachyon field, is focussed on the holographic second Randall-Sundrum (RSII) cosmology. The corresponding observational parameters, the scalar spectral index and the tensor-to scalar ratio, are determined and their values are compared with observational data.