Calendar

Gen
1
Gio
Positivity Constraints on Lorentz-breaking EFTs (Paolo Criminelli, ICTP) @ Aula 500 e online
Gen 1 1970@1:00 am–Feb 7 2106@7:28 am

Seminario di Fisica Teorica-

The coefficients of the operators of an effective field theory (EFT) are constrained to satisfy certain inequalities, under the (mild) assumption that the UV completion satisfies general requirements of causality and unitarity. We begin the extension of these ideas to theories where the Lorentz symmetry is spontaneously broken, as it happens in cosmology and condensed matter physics. Constraints are derived using dispersive arguments for the 2-point function of conserved currents and of the stress-energy tensor.

Per connettersi a zoom:

https://infn-it.zoom.us/j/93341311520?pwd=RklTcFFVWjdtUzR5TUZKM3V1TjJiQT09

Apr
14
Mer
The puzzling behavior of pentaquarks and tetraquarks @ on-line
Apr 14@11:00 am–12:00 pm

Colloquium – Dr.ssa Elena Santopinto
Quarks that combine in much more complex ways than scientists expected can have repercussions in many fields, not only in particle physics, but in astronomy, from neutron stars to dark matter. The recent observation by LHCb of a meson made of four charm quarks (T_cccc) and of three pentaquark states (P_c^+) has consecrated the subject of exotics as a hot topic. New experiments at LHC and Belle plan to shed light on this unexpected behavior
and try to understand the strong force at long distance. In this talk, some of the main experimental findings and theoretical predictions given before the experimental discoveries, regarding fully charm tetraquarks and pentaquarks, will be presented and discussed.

Per partecipare: gruppo Teams Università di Genova numero 1npbr0h (se si possiede un account Teams Unige, si può accedere con il codice. Se invece si possiede solo un account Teams INFN, scrivere a simone.marzani@ge.infn.it per essere aggiunti come ospiti).

Apr
21
Mer
Low mass Drell-Yan measurement in p-p collision at √s = 13 TeV using the ATLAS detector at the LHC @ on-line
Apr 21@11:00 am–12:00 pm

Seminario di Fenomenologia – Dr. Alessandro Guida (Genova Univ. and DESY Hamburg)

High energy physics experiments are performed at the Large Hadron Collider at CERN colliding bunches of protons at energies up to 13 TeV. The ATLAS experiment, with its multipurpose detector, studies the products of these colli- sions and compares the experimental measurements with the predictions of the Standard Model. This talk presents the study of the process Z/γ∗ → μμ at low invariant mass of the di-muon pair, in the region between 7 GeV and 60 GeV, below the Z boson resonance mass peak (mZ = 91.2 GeV). The single and double differential cross sections of the process are measured in 13 TeV proton-proton collisions at the LHC, using the ATLAS detector. The measurement explores an extreme region of the phase space and is sensitive to resummation results in the theoretical prediction. The analysis exploits the good resolution of the ATLAS detector in reconstructing low momentum muons. The main difficulties come instead from the high background component that enters in the event selection, the triggering of events and the modelling of some key physical quantities.The main features of the analysis, the studies done to overcome the main challenges, as well as the first results and comparison to theory predictions are presented in the talk.

Per partecipare: gruppo Teams Università di Genova numero 1npbr0h (se si possiede un account Teams Unige, si può accedere con il codice. Se invece si possiede solo un account Teams INFN, scrivere a simone.marzani@ge.infn.it per essere aggiunti come ospiti).

Apr
27
Mar
Measuring the muon magnetic anomaly with the Muon g-2 experiment at Fermilab @ on-line
Apr 27@11:00 am–12:00 pm

Seminario Colloquium – Dr. Marco Incagli (INFN Pisa)

The recently published result by the Fermilab Muon g-2 experiment on the muon anomaly a_mu, based on the first dataset collected in Spring 2018, confirms the discrepancy of the observed value from the currently Standard Model prediction, reaching 4.2 standard deviations. The data already collected, and currently under analysis, will half the current uncertainty, while the full dataset, including the run programmed to be concluded in June 2022, will reduce the error by a factor of 4, thus potentially allow for a discovery of new physics beyond the Standard Model.
After a historical introduction, the experiment will be reviewed, discussing the critical issues of the first set of data and how they have been addressed in view of the high statistics Runs.
Recent theoretical developments will be also presented.

Per partecipare: gruppo Teams Università di Genova numero 1npbr0h (se si possiede un account Teams Unige, si può accedere con il codice. Se invece si possiede solo un account Teams INFN, scrivere a simone.marzani@ge.infn.it per essere aggiunti come ospiti).

Apr
28
Mer
Broken translation invariance for fluids in external magnetic fields @ on-line
Apr 28@11:00 am–12:00 pm

Seminario di Fisica Teorica – Dr. Daniel Brattan (Genova Univ.)

I will review our recent works concerning a large class of systems with spontaneous, pseudo-spontaneous and explicitly broken translation invariance in the presence of an external magnetic field. In particular I will show how the Ward identities constrain the transport coefficients of hydrodynamics. We will discuss a holographic realisation of these analytic results and place them in the wider context of the quasi-hydrodynamic programme.

Per partecipare: gruppo Teams Università di Genova numero 1npbr0h (se si possiede un account Teams Unige, si può accedere con il codice. Se invece si possiede solo un account Teams INFN, scrivere a simone.marzani@ge.infn.it per essere aggiunti come ospiti).

Mag
3
Lun
CDS @ on-line
Mag 3@2:00 pm–3:00 pm

Consiglio di Sezione – Consuntivi

Ordine del Giorno:
1) Comunicazioni del Direttore dal Consiglio Direttivo
2) Presentazioni dei consuntivi da parte dei Coordinatori
3) Politica pubblicazioni Open Access (intervento di Andrea Chincarini)
2) Varie ed eventuali

Mag
5
Mer
Holographic correlators in AdS_3 @ on-line
Mag 5@11:00 am–12:00 pm

Seminario di Fisica Teorica – Dr. Stefano Giusto (Genova Univ.)

I will review recent results on the computation of correlators in the strongly coupled CFT holographically dual to AdS$_3times S^3$ in the limit of large central charge. The derivation of the correlators bypasses the standard technique based on Witten diagrams and uses the geometry dual to coherent multi-particle states. I will also discuss various properties of the correlators: their Regge limit, their OPE analysis and a surprising 6D conformal symmetry that constrains the correlators.

Per partecipare: gruppo Teams Università di Genova numero 1npbr0h (se si possiede un account Teams Unige, si può accedere con il codice. Se invece si possiede solo un account Teams INFN, scrivere a simone.marzani@ge.infn.it per essere aggiunti come ospiti).

Mag
12
Mer
Turbulent hydrodynamics in strongly correlated Kagome materials @ on-line
Mag 12@11:00 am–12:00 pm

Seminario di Fisica Teorica – Dr. Ioannis Mattheakakis (Wurzburg Univ.)

In recent years a lot of interest has been directed towards realizing strongly-coupled electronic fluids. This interest is partly because a stronger coupling enables the transition to the hydrodynamic regime and partly because of the novel transport phenomena such a fluid promises. Strongly-coupled fluids are also a natural and fertile ground for testing and refining our understanding of AdS/CFT and holography in general. In this talk, I will first show that Kagome materials with a relativistic spectrum are a compelling platform for realizing strongly-coupled fluids. Then, I will employ holography to estimate their ratio of shear viscosity to entropy density. With that estimate at hand, I will finally argue that strongly-coupled Kagome fluids put for the first time non-linear hydrodynamic phenomena such as turbulence within experimental reach.

Per partecipare: collegarsi al meeting Zoom

Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271

Mag
19
Mer
The legacy of HL-LHC for the Standard Model EFT @ on-line
Mag 19@11:00 am–12:00 pm

Seminario di Fenomenologia – Dr. Riccardo Torre (INFN Sezione di Genova)

The LHC and HL-LHC physics program is not even half-way and the absence of new physics signals claims for a strategy to build what will be the HL-LHC legacy in terms of new physics searches. The lack of signals of light new physics have put the model independent Effective Field Theory (EFT) approach forefront in looking for deviations of observables from their Standard Model predictions. There are mainly three directions in which the EFT program is meeting precision and is expanding its potentials: on-shell Higgs measurements, low energy observables (flavor), and high energy precision. These three are generally described by different sectors of the Standard Model EFT (SMEFT): schematically, Higgs on-shell observables correspond to Higher Dimensional Operators (HDO) involving additional Higgs fields, flavor observables to SMEFT operators at scales well below the EW gauge boson masses (both flavor violating and flavor conserving), while high energy observables correspond to similar operators at scales much above the EW gauge boson masses. Obviously, exploiting the interplay of the three, and combining their information, becomes crucial in building an overall picture.
In this talk I will introduce the three directions highlighted above and then focus on the third: high energy precision. I will introduce the concept of BSM measurements (to be contrasted with SM measurements and BSM searches) and try to motivate why, in my view, this will be the crucial step needed to build what could become the HL-LHC legacy.

Per partecipare: collegarsi al meeting Zoom

Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271

Mag
26
Mer
Semiclassical gravity and evaporation of dynamical black holes sourced by the quantum trace anomaly @ online
Mag 26@11:00 am–12:00 pm

Seminario di Fisica Teorica – Paolo Meda (Università di Genova e INFN di Genova)

A first approximation to describe the interplay between quantum matter and gravity is given by the quantum field on curved spacetimes and the semiclassical gravity, in which the backreaction of a quantum matter field propagating over a fixed spacetime geometry can be analyzed by using the so-called semiclassical Einstein equation. In this framework, the evaporation of four-dimensional spherically symmetric black holes can be explained by the appearance of an ingoing negative energy flux at the apparent horizon, which induces a negative variation of the black hole mass. I will show that this flux can be sourced by the trace anomaly of the quantum stress-energy tensor in case of a massless conformally-coupled scalar field once a certain averaged energy condition is assumed outside the horizon. As an example, I will compute the negative flux and the rate of evaporation in the Vaidya spacetime, which describes the exterior geometry of a null radiating star.

Per partecipare: collegarsi al meeting Zoom

Topic: Theory and Pheno seminars

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