Calendar

Mar
6
Mer
COSMOLOGY OF THE QCD AXION: FROM THERMAL TO INFLATIONARY PRODUCTION (Alessio Notari, Universitat de Barcelona) @ Aula 501
Mar 6@2:00 pm–3:30 pm

Seminario Fisica Teorica

The axion is a hypothetical particle that could explain the absence of CP violation in QCD and has a very rich cosmological phenomenology.
In particular a population of thermally produced axions is expected to exist, in addition to a cold dark matter population. I discuss a new conservative bound on the axion mass, from production in the early universe from scattering with pions. In addition I will show that to exploit the reach of upcoming cosmological surveys, non-perturbative calculations above the QCD crossover are needed. Moreover I will also review production from other Standard Model particles (quarks, leptons).
Then, I will discuss the axion cold dark matter population, showing that its abundance depends on non-trivial evolution during primordial inflation.
Finally I will discuss the non-standard case of a heavy QCD axion, which could give rise to a detectable gravitational wave signal at Pulsar Timing Arrays or at interferometers.

Per connettersi a zoom:

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Mar
7
Gio
Inflationary scenario and de Sitter conjecture ( Dr Kunihito Uzawa, Kwansei Gakuin Univ. and Keio Univ.) @ Aula 605
Mar 7@2:00 pm–3:00 pm

Seminario Fisica Teorica

Several simple criteria were proposed to assess if vacua emerging from an effective scalar field theory are part of the string “landscape” or “swampland”. However, there has been little attempt to examine the swampland criterion against explicit context of kinetic terms made up of scalar fields. In this presentation, we discuss the universal behavior that in the region wherein the moduli are expected to be stable, the theory of gravity may be part of the landscape. By contrast, in the region where they may be faithful runaway potential, in the sense they possess a finite kinetic term for scalar field, the theory should thus be part of the swampland. We also consider the inflationary scenario interpolating between the cosmological landscape and the swampland and establish the part of the domain of existence where the swampland criteria are violated.

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Mar
13
Mer
Holographic match of subleading corrections to the BPS entropy of AdS5 black holes (Dr. Alejandro Ruiperez, INFN Roma 2) @ Aula 501
Mar 13@2:00 pm–3:00 pm

Seminario di Fisica Teorica

The Bekenstein-Hawking entropy of supersymmetric AdS5 black holes is matched holographically via the Legendre transform of the superconformal index on the second sheet. In this talk I shall show how this approach can be extended to account for subleading corrections to the Bekenstein-Hawking entropy, which are computed in the gravity side by adding suitable higher-derivative corrections. After reviewing the universal case studied in 2208.01007 (and 2304.06101), I will focus on ongoing work aimed to understand the case in which the black hole is charged under additional flavor symmetries.

Per connettersi a zoom:

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Mar
20
Mer
TBA (Saso Grozdanov, Edimburgh)
Mar 20@2:00 pm–3:00 pm
Mar
27
Mer
SMEFT vs HEFT for new physics searches at the LHC (Ilaria Brivio, Università di Bologna) @ Aula 501
Mar 27@2:00 pm–3:00 pm

Semina di Fenomenologia delle Particelle Elementari

Over a decade after the Higgs discovery, the hunt for physics beyond the Standard Model is incorporating more and more searches for small, non-resonant traces of new physics, that can be described by an Effective Field Theory (EFT).
The so-called Standard Model EFT (SMEFT) is now the standard framework used for these searches. The Higgs EFT (HEFT) is an alternative extension of the SM, which differs from SMEFT in the representation chosen for the scalar fields, a feature that results in a higher complexity and that, so far, has made HEFT less attractive for phenomenological studies.
Nevertheless, it is well-established that HEFT is more general than SMEFT, implying the existence of BSM scenarios which would be captured by the former but not by the latter. HEFT could also represent a useful candle to test the validity of the dimension-6 SMEFT approximation, an issue that has been raising significant concerns for LHC measurements.
After an introduction to the two frameworks, the first half of the talk will give an overview of the phenomenological characterization of HEFT and SMEFT. The second part will explore more formal aspects of the HEFT-SMEFT interplay, that build on a geometric description of the scalar sector.

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Apr
3
Mer
Precise QCD for associated top production ( Dr Simone Devoto, U. Ghent) @ Aula 501
Apr 3@2:00 pm–3:00 pm

Seminario di Fenomenologia delle Particelle Elementari

The production of a top quark pair in association with a heavy boson is a class of processes of high importance at LHC, both for precision Standard Model studies and new physics searches: top-pair production in association with a Higgs boson allows for a direct measurement of the top-quark Yukawa coupling, while the cross section of top-pair production in association with a W boson has been observed consistently higher than the Standard Model value by different experimental collaborations.
In this talk we present our recent computation of the NNLO QCD corrections to both these processes, with an emphasis on their phenomenological applications.

Per connettersi a zoom:

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

Apr
10
Mer
TBA (Prof Matteo Viel (SISSA))
Apr 10@2:00 pm–3:00 pm

Physics Colloquia

Apr
17
Mer
TBA (Ilaria Archidiacono, UniMi)
Apr 17@2:00 pm–3:00 pm
Apr
24
Mer
TBA (Alessandro Giachino, IFIC)
Apr 24@2:00 pm–3:00 pm
Mag
8
Mer
Climate change: from science to action (Dr Elisabetta VIGNATI (Head of Unit and Deputy Director Joint Research Centre Directorate C, Energy, Mobility and Climate Clean Air and Climate Unit))
Mag 8@2:00 pm–3:00 pm

Physics Colloquia
Abstract:
Climate change is one of the most challenging global issues that humankind faces. The earth average surface temperature has risen more than 1 degree since the pre-industrial time and 2023 was the warmest year since 1880, year when modern measurement records began. The basic chemistry and physics of climate change have been understood for more than a century and effects already well documented. Science and research have significantly improved our understanding of the causes and our response options: human activities are estimated to have caused the temperature increase since pre-industrial time and global warming is projected to increase if substantial and sustained actions to reduce the human impact are not taken soon. Exploring the pivotal role of science in shaping international and European climate change policy, we delve into the dynamic interplay between scientific advancements and policy decisions as the scientific community’s influence is undeniable, driving evidence-based strategies that navigate the complex challenges of climate change.