Seminario di Fenomenologia –

The stochastic gravitational waves background is a rich resource of cosmological information, encoded both in its source statistics and its anisotropies. During their journey, the gravitational waves constituting the background encounter cosmic structures, which are able to modify the observed signal. According to the ratio between the wavelength of the wave, and the matter overdensities typical length-scale, interference and diffraction effects may arise, possibly boosting the signal’s amplitude or inducing a non-trivial polarization pattern. In this talk I will present results about the wave-optics limit of the stochastic gravitational wave background, and describe how we can use them to gain information about the matter content of the Universe.

Per connettersi a zoom:

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271Meeting ID: 857 318 5271

Seminario di Fisica Teorica –

I will present the classification of all unitary, rational conformal field theories with one non-trivial primary and central charge c < 25. (with Brandon Rayhaun, arXiv: 2208.05486). I will also, more briefly, review a partial classification of theories with two nontrivial primaries, as well as some new predictions on the existence of meromorphic CFT with central charge 32.

Per connettersi a zoom:

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271

Meeting ID: 857 318 5271

Seminario di Fisica Teorica –

Hydrodynamics is the effective theory that governs the transport of charge, energy and momentum at late times and large distances. In certain circumstances this description must be modified to include the fact that these charges decay very slowly; for example when there are chemical processes or spatial translation invariance is broken. In this talk I will primarily discuss how to incorporate such “relaxation” processes into the effective theory of a fluid driven by an electric field. Given sufficient time I will place this work in the larger context of the relaxed hydrodynamics programme and tease new results.

Per connettersi a zoom:

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271

Meeting ID: 857 318 5271

Seminario di Fenomenologia –

Axion-like particles (ALPs) are one of the most attractive solutions to the dark matter issue.

In this talk, I will discuss how to search for ALPs in astrophysical structures.

After some introduction, I will focus on the emission associated with their decay into photons.

The discussion will involve different ALP mass ranges and wavelength bands.

Per connettersi a zoom:

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271

Meeting ID: 857 318 5271

Seminario di Fisica Teorica –

This talk revolves about low-energy effective field theories with fractonic degrees of freedom characterised by mobility constraints. The fractonic features descend from spatially-dependent rigid symmetries, like sub-system symmetries and multipole symmetries. We focus mainly on the emergence of fractonic dynamics in standard elastic theory and generalization thereof. Elastic defects behave at low energy as fractons and they can be described as the charged objects of a dual gauge theory through Hubbard-Stratonovich duality. We propose to formulate such dual gauge theory purely in terms of standard vector gauge fields, as opposed to the customary formulation in terms of tensor gauge fields. The new formulation is promising in view of addressing some fundamental open questions related to the coupling of fractonic theories to a background geometry, relevant for their theoretical consolidation as well as for applications. If time allows, we also comment on the relation of fractons with dynamical breaking of translation symmetry and the possibility to UV complete some known fractonic models.

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271

Meeting ID: 857 318 5271

Seminario di Fenomenologia –

General-purpose Monte Carlo event generators are omnipresent in collider physics. As an introduction, I will discuss the various building blocks entering such tools. The talk will focus on the core part, the so-called parton-shower algorithm. I will what it is meant to achieve, i.e. connections with all-order calculations in perturbative QCD, and how it does it in practice, i.e. (usually) as a dipole shower. The main part of the talk will, describe the effort of the PanScales collaboration in order to improve the current state-of-the-art.

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271

Meeting ID: 857 318 5271

Seminario di Fenomenologia –

Although not being a dedicated heavy-flavour physics experiment at LHC, ATLAS experiment has a wide programme in that field and produces very competitive results. B-physics studies in ATLAS are mainly based on (multi-)muon signatures and benefit from large available statistics of pp collisions, perfect muon system and optimized triggers for B-physics.

An overview ATLAS B-physics opportunities is given, focusing on the triggers and updates made for LHC Run-3.

Selected recent results are discussed then, including onia production measurements and studies of B_c meson which aim at probing the QCD predictions, exotic hadron spectroscopy, and CP violation measurements in B decays, sensitive to possible BSM physics contributions.

Finally, future prospects are outlined for possible B-physics studies with Run-2 and Run-3 data.

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271

Meeting ID: 857 318 5271

Seminario di Fenomenologia –

I shall review novel approaches that I have explored over the years to extract information optimally from varied observations across the electromagnetic spectrum. The aims are varied as well, and in particular I shall discuss: optimising parameter constraints for the concordance cosmological model; testing the inflationary principle through measuring its non-Gaussian imprint on the cosmic large-scale structure; confirming the validity of general relativity on the largest cosmic scales; probing the particle nature of dark matter; and learning about the origin and composition of ultra-high energy cosmic rays.

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271

Meeting ID: 857 318 5271

Seminario di Fenomenologia –

The role of precise nuclear physics theories and models is increasing in neutrino physics. This has been recognized in low-energy neutrino experiments for many years, but recent progress of accelerator-based neutrino oscillation experiments emphasizes the importance of nuclear physics, or many-body nuclear problems. Modern neutrino oscillation experiments, such as T2K and NOvA, require us to simulate nucleon correlations, and this trend will continue with future experiments, including DUNE and Hyper-Kamiokande. Surprisingly, the need of such nuclear theory is everywhere in high-energy particle physics, and new calculations reveal previously ignored connections between nuclear physics and particle physics.

In this talk, I outline the status of neutrino interaction physics, focusing on the 1 to 10 GeV region which is critical to neutrino oscillation experiments. Special attention is paid to the recent developments in nuclear models which made contributions to neutrino physics.

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271

Meeting ID: 857 318 5271

Seminario di Fisica Teorica –

In this talk I will show that the main properties of the fracton quasiparticles can be derived from a generalized covariant Maxwell-like action. Starting from a rank-2 symmetric tensor field, a partially symmetric rank-3 tensor field strength can be built, which obeys a kind of Bianchi identity. The most general action invariant under the covariant “fracton” transformation consists of two independent terms: one describing Linearized Gravity (LG) and the other referable to fractons, a proof of the always suspected relation between fractons and gravitons. I will also discuss that, as claimed in the Literature, the fracton part can be reconduced to a generalized Maxwell theory. In particular, in the covariant generalization of the fracton theory, the equations describing the fracton limited mobility, i.e. the charge and dipole conservation, are not external constraints, but rather consequences of the field equations of motion, hence of the invariant action and, ultimately, of the fracton covariant symmetry.

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271

Meeting ID: 857 318 5271