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PubblicazioneRedshift-space distortions in massive neutrinos cosmologies( 2025)We study the Kaiser formula for biased tracers in massive neutrino cosmologies by comparing its predictions with a large set of N-body simulations. In particular, we examine the ambiguity in the definition of the peculiar velocity contribution at linear level, whether it should be expressed in terms of the total matter velocity field or only the cold-matter component, comprised of cold dark matter and baryons. We revisit and extend previous qualitative studies on the topic with larger statistics and including a full fit of halo power spectrum and halo-matter cross-power spectrum measurements. We find clear evidence that the clustering of halos in redshift space is correctly described assuming that halo velocity is tracing the velocity field of cold-matter. The opposite assumption provides a worse fit to the simulated data and can lead to a spurious running of nuisance parameters in the perturbative galaxy power spectrum model.
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PubblicazioneQuantum signatures and decoherence during inflation from deep subhorizon perturbations( 2026)In order to shed light on the quantum-to-classical transition of the primordial perturbations in single field inflation, we investigate the decoherence of large-scale (superhorizon) scalar curvature perturbations. The latter are considered as an open quantum system which undergoes quantum decoherence induced by a time-dependent environment of deep subhorizon tensorial modes through the trilinear interactions predicted by General Relativity. A complete calculation is a complex one and still to be fully performed. We advance in that direction, and we elaborate on various aspects that have been overlooked in the literature. We first prove that, in full generality, a time dependent subhorizon environment can be relevant for decoherence during inflation, by considering derivativeless interactions, which, in our case, give the most important results. For the first time, the time dependence of the environment is properly taken into account by modifying the quantum master equation. Important non-Markovian effects pop up, instead, when dealing with derivative interactions. We adopt a possible way to treat them which has been recently proposed and seems well suited for our case. Our results show that when considering the interplay between derivativeless and derivative interactions, decoherence is slowed down. This underlines the importance of accounting for all the interactions in open quantum-system calculations in an inflationary setting. We finally compute the quantum corrections to cosmological correlation functions, by solving the transport equations induced by the quantum master equation. We also compare the results to the solutions obtained by an alternative method previously used in the literature. We observe a resummation of the quantum corrections to the power-spectrum of the Sasaki Mukhanov variable v, which is a general property of quantum master equations. We extend these results to the bispectrum of v.
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PubblicazioneHydrogen Detachment in Diprotic Aromatics: O–H versus N–H Photodissociation in m-Aminophenol( 2026)While the photochemistry of aromatics with a labile hydrogen atom has been broadly characterized through molecular beam experiments and electronic structure simulations, much less is known regarding the photodissociation of species with more than one exchangeable hydrogen. Fundamental questions like the relative probabilities for the scission of the different X-H bonds, the involved excited states and reaction mechanism, or even the possible photogeneration of diradicals and H2 as a byproduct, remain largely unexplored. On the basis of nonadiabatic molecular dynamics simulations at the TDDFT level, confronted and validated against CASSCF/NEVPT2 calculations, this study addresses these questions for m-aminophenol, a diprotic heteroaromatic compound featuring hydroxyl and amino functions. We find unequal propensities for O-H and N-H dissociation, and the stabilization of the radical products. Data science tools allow us to identify the reaction coordinates leading to dissociation in each case, identifying two very different pathways that result in the observed trends.
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PubblicazioneBounds from D/H on baryogenesis models( 2026)We review the constraints on baryon inhomogeneities derived from measurements of the deuterium abundance, D/H, and apply them to a range of baryogenesis models. In particular, we derive bounds on electroweak baryogenesis as well as on more exotic scenarios. Our results show that, across most of the relevant parameter space, electroweak baryogenesis remains largely unconstrained by current and foreseeable D/H measurements. By contrast, the constraints on alternative scenarios are significantly stronger and can exclude regions of parameter space that would otherwise remain viable.