The persistent discrepancies between predictions of the standard cosmological model and high-precision measurements across multiple probes remain a significant challenge in modern cosmology. Over the past decade, mounting evidence for tensions in key cosmological parameters - derived through both model-dependent and independent methods - has motivated the exploration of extensions to the...
In this talk [based on 2602.10078], I will show how measurements of the intergalactic medium (IGM) temperature from the Lyman-α forest can be used to constrain long-lived dark sector particles with lifetimes larger than 10¹⁶ s. Such particles deposit energy into the IGM through decays to Standard Model states, thereby modifying its late-time thermal history. I will also revisit constraints on...
LIGO, VIRGO and Kagra (just to name a few) represent outstanding feats of engineering that have launched us in a new era of gravitational-wave (GW) detection. Even so, we may wonder whether their sensitivity is enough to detect very high-frequency signals of beyond-Standard-Model origin, such as those sourced by primordial stochastic GW backgrounds, primordial black holes, or black hole...
Resonant production via active–sterile neutrino oscillations in the presence of large lepton asymmetries (the Shi–Fuller mechanism) remains a compelling scenario for keV-scale sterile neutrino dark matter. For a long time, the constraints on such asymmetries were obtained thanks to big bang nucleosynthesis and cosmic microwave background measurements, but did not properly account for the...
The dynamics of neutrinos and antineutrinos at MeV temperatures sets the Standard Model prediction for the effective number of relativistic species, N_{eff}, a key target for upcoming CMB and BBN measurements. Reaching a suitable theoretical accuracy demands control over sub-percent effects in the relevant interaction rates. In this talk I will review recent progress on precision calculations...
The particle nature of dark matter remains one of the most important open questions in physics. An intriguing clue is the γ-ray excess observed by Fermi-LAT toward the Galactic Center, whose spectrum resembles the expected signal from annihilating weakly interacting massive particles. However, many conventional dark matter models are now strongly constrained by direct detection and collider...
Indirect searches for Dark Matter (DM) particles with mass in the MeV - GeV scale have received significant attention lately. Pair-annihilations of such DM particles in the Galaxy can give rise to MeV - GeV gamma-rays via prompt emission, sub-GeV e+e-'s in cosmic-rays, as well as a broad photon spectrum ranging from X-rays to soft gamma-rays, produced by the secondary emissions from DM induced...
The piezoaxionic effect enables the conversion of axion-induced nuclear Schiff moments into measurable voltages in piezoelectric crystals. We propose a heterodyne implementation in which controlled nuclear spin dynamics are used to mix the axion oscillation frequency with the nuclear Larmor frequency. This produces sideband signals that allow frequency scanning through the applied magnetic field.
Gauge-fermion theories and their IR fate remain puzzling mysteries in QFT, even after decades of study. Beyond their theoretical interest, they may play a natural role in extensions of the Standard Model, such as grand unified theories, dynamical symmetry breaking, and models of quark and lepton substructure. Yet our limited understanding of their nonperturbative dynamics severely hampers...
We compute hadronic vacuum polarization, an observable whose precision limits several important tests of the Standard Model, using two-flavor chiral perturbation theory to three loops (next-to-next-to-next-to-leading order). Particular attention is given to the loop integrals, several of which are not found in literature, and which display a novel set of relations beyond what is found through...
The spectrum of light hadrons encodes essential information about the non-perturbative dynamics of QCD. Most observed hadrons are resonances, rigorously defined as poles of scattering amplitudes in the complex energy plane. Their properties, such as masses, widths, and couplings, are therefore determined by the analytic structure of the amplitudes describing low-energy hadronic interactions....
Quarkonia are bound states formed by a heavy-quark pair. They are commonly described within the framework of non-relativistic QCD. Yet, this description is not sufficient to fully exploit data involving quarkonium production, which still hide precious information and call for theoretical improvements. In this talk, I will try to give a (biased) perspective on what quarkonium physics can teach...
We begin by reviewing how NLL accuracy is achieved in modern parton showers—highlighting the recent Sherpa implementation—and then introduce our new information-theoretic matching framework to achieve beyond NLL accuracy. By minimizing a Kullback–Leibler functional under constraints set by precision QCD input observables (including theory uncertainties), we embed high-order predictions into...
We will discuss the recent developments in renormalization group improvements of the cold and dense QCD pressure (Phys. Rev. D 111, 034020 and Phys. Rev. Lett. 129, 212001) at next-to-next-to leading order (NNLO) through the renormalization group optimized perturbation theory (RGOPT) and at all-order resummation of the soft modes. RGOPT applied for the very first time at NNLO displayed a...
Very high energy electrons passing through ordinary matter initiate electromagnetic showers that are produced by bremsstrahlung and pair production. At extremely high energies, the quantum-mechanical duration of these processes becomes longer than the mean free time for elastic scattering in the medium, which leads to a significant suppression of bremsstrahlung (and pair production). This...