Colloquium – Dr. Fabrizio Ferro (INFN Sezione di Genova)
The Odderon, first theorized in 1973, represents the C-odd counterpart of the Pomeron, the dominant Regge trajectory in the soft high energy diffractive interactions. The Odderon emerges not only in the Regge framework, but also in QCD theory where it can be modelled as an exchange of a colourless C-odd gluonic compound. States comprising two, three or more gluons are usually called “glueballs”, and their observation represents a key test of the QCD. The TOTEM experiment at LHC has performed total and differentialelastic p-p cross-section measurements at different LHC energies.
Since 2018 a first hint of the presence of the Odderon was found in TOTEM results. Now the discovery has been confirmed after a comparison with the p-bar-p data measured by the D0 collaboration at Fermilab. The comparison of the two experiment results led to the first experimental observation of the exchange of the Odderon with a significance of 5.4σ.
Per partecipare: collegarsi al meeting:
Topic: Colloquium: “TOTEM and D0: the observation of the Odderon”
Join Zoom Meeting
https://cern.zoom.us/j/67205268399?pwd=cmlMTkdEZEFONExwbytNODZBbXVBUT09
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Seminario di Fisica Teorica – Dr.ssa Elisa Ercolessi (Università di Bologna)
Quantum technologies offer a platform for analogue simulations and digital quantum computations of Lattice Gauge Theories within a Hamiltonian approach.
We will discuss the theoretical framework necessary to approximate the continuous theory, giving some examples of both abelian and non-abelian discrete models.
We will discuss how this approach allows also for the study of non-perturbative effects and real-time dynamics.
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Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271
Consiglio di Sezione – Preventivi
Preventivi
Seminario DIFI/INFN di Fenomenologia delle Particelle Elementari – Prof. Ian Moult (Yale University)
Collimated sprays of hadrons, called jets, are an emergent phenomenon of Quantum Chromodynamics (QCD) at high energies. Understanding the detailed energy flow, or substructure, of jets has come to play a central role at the Large Hadron Collider (LHC), where it has enabled new ways to search for physics beyond the Standard Model, as well as new insights into the strong interactions.
In this talk I will present recent developments in improving our theoretical understanding of jet substructure using insights from conformal field theory. I will show that jet substructure can be formulated as the study of matrix elements of particular lightray operators enabling the use of powerful techniques such as the operator product expansion (OPE), and providing an alternative approach to thinking about jet substructure more closely related to scaling phenomena. I will then show that the remarkable data quality of the LHC allows the scaling behavior predicted by the OPE to be directly measured in data, illustrating an interesting interplay between recent developments in CFT and LHC phenomenology.
Per partecipare: collegarsi al meeting Zoom
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271
Seminario di Fisica Teorica INFN/DIFI – Carlo Heissenberg (Nordita, Stockholm, Sweden)
The eikonal exponentiation of gravity amplitudes is a non-perturbative re- summation whereby certain high-energy divergent terms, which would naively violate unitarity bounds, combine into a harmless phase factor. Eikonal tech- niques also offer a natural strategy to calculate classical gravitational observables directly from the loop-expansion of scattering amplitudes. In this talk, I will discuss how the eikonal can be applied to obtain the deflection angle for the collision of two non-spinning black holes with generic center-of-mass energies, up to order O(G3). This calculation captures both conservative and dissipa- tive radiation-reaction effects, and yields a deflection angle with a smooth behavior at high energies, where it agrees with the universal massless result. Besides explicit two-loop calculations, I will also illustrate a shortcut to access radiation-reaction effects based on analyticity, unitarity and crossing symmetry. Finally, I will sketch how the classical limit of inelastic five-point amplitudes fits in the eikonal exponentiation of elastic four-point amplitudes and provides the leading-order waveforms for the emission of gravitational waves.
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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271
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Seminario di Fisica Teorica INFN/DIFI – Prof. Domenico Seminara (Università di Firenze e INFN)
Recently Jackiw-Teitelboim gravity has provided a 2D laboratory where to explore and investigate some ideas about quantum gravity. After reviewing some of these aspects,
I will discuss the nonperturbative structure of Jackiw-Teitelboim gravity at finite cutoff, as given by its proposed formulation in terms of a deformed Schwarzian quantum mechanics.
When expressed as a perturbative expansion in the deformation parameter, the disk partition function gives rise to an asymptotic series that admits a precise completion as prescribed
by resurgence theory. This formalism can be extended to arbitrary topologies using the basic gluing rules of the undeformed case. I will present exact results for general topologies
and show that these are captured by a suitable deformation of the Eynard-Orantin topological recursion.
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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271
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Seminario di Fenomenologia delle Particelle Elementari INFN/DIFI – Dr Lorenzo Ubaldi (SISSA)
After a brief introduction to the strong CP problem, I will introduce the axion as a solution and explain how it also provides a cold dark matter candidate. In the second part of my talk I will focus on cosmological scenarios with a low scale of inflation, and discuss a mechanism that can generate enough axion relics to match the observed dark matter abundance even in such scenarios.
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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271
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Seminario di Fisica Teorica INFN/DIFI – Davide Astesiano (Università dell’Insubria)
To analyze the dynamics of a single spiral galaxy, we will discuss the known class of exact stationary axially-symmetric solutions to Einstein gravity coupled with neutral dust. Differently from the Newtonian description of the same system where all the quantities are completely fixed once the velocity or the matter distribution are known, the class of the relativistic solutions provides additional degrees of freedom, making the applications of this system much more interesting and wide. Up to now, from the relativistic perspective the already proposed models for galaxies are the co-rotating and the differentially rotating model. While in the first case the velocity of the dust satisfies L_u(g) = 0, in the second case it differs from zero. What is interesting about these solutions is that the low energy limits are non equivalent to the Newtonian theory. In particular, the differentially rotating case generalize the known results of Balasin and Grumiller and further highlights the discrepancy between Newtonian theory of gravity and general relativity at low velocities and energy densities. Using these exact solutions, we push forward the idea that the “inertia” of the gravitational field can simulate dark matter effects. In fact, we show that non co-rotance further reduces the amount of energy density required to explain the rotation curves for spiral galaxies.
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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271
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