arXiv subjects

Alessandra D'Alise

Publications and source records attributed to Alessandra D'Alise.

14 recordsLinked to original sources

arXiv2026

Affine Symmetry and the Group-Theoretic Basis of the Unruh Effect

A massless scalar field in two spacetime dimensions splits into two independent sectors of left and right-moving modes on the light cone. At the quantum level, these two sectors carry a representation of the group of affine transformations of the real line, with translations corresponding to transformations generated by light-cone momenta and dilations given by light-cone Rindler momenta formed by a linear combination of generators of boosts and dilations. One-particle states for inertial observers are eigenvectors of translation generators belonging to irreducible representations of the affine group. Rindler one-particle states are related to eigenfunctions of the generator of dilations. We show that simple manipulations connecting these two representations involving the Mellin transform can be used to derive the thermal spectrum of Rindler particles observed by an accelerated observer. Beyond providing a representation-theoretic basis for vacuum thermal effects, our results suggest that analogous phenomena may arise in any quantum system admitting realizations of translation and dilation eigenstates.

hep-th↗

arXiv2025

Four-Fermion Deformations on Line Defects in QED$_4$ with Yukawas

We elucidate the dynamics induced by a Wilson Line of charge $q$ and electron charge $e$ in $QED_4$ coupled to a real scalar via Yukawa interactions. We observe that there is a range of the fixed product $e^2 q$ with $e\rightarrow 0$ and $q\rightarrow \infty$ for which four-fermion operators play a dominant role for the dynamics of the theory. We uncover the fixed-point dynamics of the theory and analyze their critical behavior.

hep-th↗

arXiv2025

On the $θ$-angle physics of QCD under pressure: The strange and isospin phase diagram

We unveil the impact of the $θ$-angle on the QCD phase diagram at nonzero isospin and strangeness chemical potentials for three light flavors and different quark mass ratios. We establish the phase boundaries as well as the nature of the associated phase transitions. The order parameters and the physical spectrum in the different phases are determined. We further elucidate the physics around $θ=π$ where we discover a novel parity-preserving superfluid phase. Finally, we comment on Dashen's phenomenon in the superfluid phases when varying the number of light flavors.

hep-ph↗

arXiv2024

A Temporal Playbook for Multiple Wave Dengue Pandemic from Latin America and Asia to Italy

We show that the epidemiological Renormalization Group (eRG) framework is a useful and minimal tool to effectively describe the temporal evolution of the Dengue multi-wave pandemics. We test the framework on the Dengue history of several countries located in both Latin America and Asia. We also observe a strong correlation between the total number of infected individuals and the changes in the local temperature. Our results further support the expectation that global warming is bound to increase the cases of Dengue worldwide. We then move to investigate, via the eRG, the recent outbreak in Fano, Italy and offer our projections.

q-bio.PE↗

arXiv2024

Information index augmented eRG to model vaccination behaviour: A case study of COVID-19 in the US

Recent pandemics triggered the development of a number of mathematical models and computational tools apt at curbing the socio-economic impact of these and future pandemics. The need to acquire solid estimates from the data led to the introduction of effective approaches such as the \emph{epidemiological Renormalization Group} (eRG). A recognized relevant factor impacting the evolution of pandemics is the feedback stemming from individuals' choices. The latter can be taken into account via the \textit{information index} which accommodates the information--induced perception regarding the status of the disease and the memory of past spread. We, therefore, show how to augment the eRG by means of the information index. We first develop the {\it behavioural} version of the eRG and then test it against the US vaccination campaign for COVID-19. We find that the behavioural augmented eRG improves the description of the pandemic dynamics of the US divisions for which the epidemic peak occurs after the start of the vaccination campaign. Our results strengthen the relevance of taking into account the human behaviour component when modelling pandemic evolution. To inform public health policies, the model can be readily employed to investigate the socio-epidemiological dynamics, including vaccination campaigns, for other regions of the world.

q-bio.PE↗

arXiv2024

Entanglement entropy and horizon temperature in conformal quantum mechanics

The generators of radial conformal symmetries in Minkowski space-time can be put in correspondence with generators of time evolution in conformal quantum mechanics. Within this correspondence we show that in conformal quantum mechanics the state corresponding to the inertial vacuum for a conformally invariant field in Minkowski space-time has the structure of a thermofield double. The latter is built from a bipartite "vacuum state" corresponding to the ground state of the generators of hyperbolic time evolution. These can evolve states only within a portion of the time domain. When such generators correspond to conformal Killing vectors mapping a causal diamond in itself and generators of dilations, the temperature of the thermofield double reproduces, respectively, the diamond temperature and the Milne temperature found for massless fields in Minkowski space-time. Moreover, we compute the entanglement entropy associated to the thermofield double states obtaining a UV divergent logarithmic behaviour akin to known results in two-dimensional conformal field theory where the entangling boundary is point-like.

hep-th↗

arXiv2024

New Physics Pathways from B Processes

We re-consider recent measures of $R_{K}$ and $R_{K^*}$, now compatible with the Standard Model expectations, as well as the results for the process $\text{BR}(B_s \rightarrow μ^+ μ^-)$ alongside earlier determinations of $R_{D^{(\ast)}}$ and $\text{BR}(B_c \rightarrow τν)$. We provide analytic constraints on the associated Wilson coefficients in both the $b \to s$ and the $b \to c$ sectors. These allow us to estimate the scale of potential New Physics for generic extensions of the Standard Model. We then use the results to constrain the leptoquark landscape.

hep-ph↗

arXiv2024

Scaling results for charged sectors of near conformal QCD

We provide the leading near conformal corrections on a cylinder to the scaling dimension $Δ_Q^\ast$ of fixed isospin charge $Q$ operators defined at the lower boundary of the Quantum Chromodynamics conformal window: \begin{equation} Δ_Q = Δ_Q^\ast +\left(\frac{m_σ}{4 πν}\right)^2 \, Q^{\fracΔ{3}} B_1 + \left(\frac{m_π(θ)}{4πν} \right)^4\ Q^{\frac{2}{3}(1-γ)} B_2 + \mathcal{O}\left ( m_σ^4 , m_π^8, m_σ^2 m_π^4\right) \ . \nonumber \end{equation} The results are expressed in powers of the dilaton and pion masses in units of the chiral symmetry breaking scale $4πν$ with the theta-angle dependence encoded directly in the pion mass. The characteristic $Q$-scaling is dictated by the quark mass operator anomalous dimension $γ$ and the one characterising the dilaton potential $Δ$. The coefficients $B_i$ with $i=1,2$ depend on the geometry of the cylinder and properties of the nearby conformal field theory.

hep-th↗

arXiv2023

Cornering Quantum Gravity

After introducing the covariant phase space calculus, Noether's theorems are discussed, with particular emphasis on Noether's second theorem and the role of gauge symmetries. This is followed by the enunciation of the theory of asymptotic symmetries, and later its application to gravity. Specifically, we review how the BMS group arises as the asymptotic symmetry group of gravity at null infinity. Symmetries are so powerful and constraining that memory effects and soft theorems can be derived from them. The lectures end with more recent developments in the field: the corner proposal as a unified paradigm for symmetries in gravity, the extended phase space as a resolution to the problem of charge integrability, and eventually the implications of the corner proposal on quantum gravity.

hep-th↗

arXiv2023

The Dilatonic Dynamics of Baryonic Crystals, Branes and Spheres

We systematically analyze the impact of dilatonic dynamics on Skyrme spheres, crystals and branes. The effects of the dilatonic model parameters, encompassing different underlying near-conformal dynamics, on the macroscopic properties of Skyrmions such as their mass and radius, are discussed. For spheres and crystals we identify special values of the ratio of the decay constants for which the second order differential equations reduce to a solvable first order system. Additionally, in the case of the crystals, the dilaton presence spatially separates the baryon and isospin charge distributions. For branes, we show how the dilaton smooths out their configurations. Our results are expected to have wide implications from the study of near-conformal dynamics stemming from QCD-like theories to phenomenological investigations of nuclear matter in extreme regimes.

hep-ph↗

arXiv2023

Charging the conformal window at nonzero $θ$ angle

We determine the impact of the $θ$-angle and axion physics on the near conformal dynamics of the large-charge baryon sector of $SU(2)$ gauge theories with $N_f$ fermions in the fundamental representation. We employ an effective approach featuring Goldstone and dilaton degrees of freedom augmented by the topological terms in the theory. We investigate how different dilaton potentials, including the ones for which a systematic counting scheme can be established, affect the results. Via state-operator correspondence we compute the corrections to the would-be conformal dimensions of the lowest large-charge operators as a function of the $θ$ term and dilaton potential.

hep-th↗

arXiv2023

Entanglement entropy in conformal quantum mechanics

We consider sets of states in conformal quantum mechanics associated to generators of time evolution whose orbits cover different regions of the time domain. States labelled by a continuous global time variable define the two-point correlation functions of the theory seen as a one-dimensional conformal field theory. Such states exhibit the structure of a thermofield double built on bipartite eigenstates of generators of non-global time evolution. In terms of the correspondence between radial conformal symmetries in Minkowski spacetime and time evolution in conformal quantum mechanics proposed in arXiv:2002.01836, arXiv:2103.07228, such generators coincide with conformal Killing vectors tangent to worldlines of Milne and diamond observers at constant radius. The temperature of the thermofield double states in conformal quantum mechanics reproduces the temperatures perceived by such diamond and Milne observers. We calculate the entanglement entropy associated to the thermofield double states and obtain a UV divergent logarithmic behaviour analogous to known results in two-dimensional conformal field theory in which the entangling boundary is point-like.

hep-th↗

arXiv2022

The $θ$-angle and axion physics of two-color QCD at fixed baryon charge. Part I

We analyze the impact of the $θ$-angle and axion dynamics for two-color (in fact any $Sp(2N)$) QCD at nonzero baryon charge and as a function of the number of matter fields on the vacuum properties, the pattern of chiral symmetry breaking as well as the spectrum of the theory. We show that the vacuum acquires a rich structure when the underlying $CP$ violating topological operator is added to the theory. We discover novel phases and analyse the order of their transitions characterizing the dynamics of the odd and even number of flavours. We further determine the critical chemical potential as function of the $θ$ angle separating the normal from the superfluid phase of the theory. Our results will guide numerical simulations and novel tests of the model's dynamics. The results are also expected to better inform phenomenological applications of the model ranging from composite Higgs physics to strongly interacting massive dark matter models featuring number changing interactions. In the companion work \cite{PartII} we repurpose and upgrade the approach to determine the impact of the $θ$-angle and axion physics on non-perturbative near conformal dynamics related to the fixed baryon charge sector.

hep-th↗

arXiv2022

Standard model anomalies: Lepton flavour non-universality, g-2 and W-mass

We critically analyze the body of results that hints to the existence of New Physics from possible violations of lepton universality observed by the LHCb experiment in the $μ/e$ ratios $R_{K}$ and $R_{K^*}$ to the $g-2$ lepton anomalies. The analysis begins with a theoretical, in depth, study of the $μ/e$ ratios $R_{K}$ and $R_{K^*}$ as well as the process $B_s \rightarrow μ^+ μ^-$. Here we consider the impact of complex Wilson coefficients and derive constraints on their imaginary and real parts. We then move to a comprehensive comparison with experimental results. We show that, by fitting a single Wilson coefficient, the deviations from the Standard Model are at the $4.7σ$ level when including only the hadronic insensitive observables while it increases to $6.1σ$ when including also the hadronic sensitive ones. When switching on all relevant Wilson coefficients and combining both hadronic sensitive and insensitive data into the fit, the deviation from the Standard Model peaks at $7.2σ$ and decreases at the $4.9σ$ level if we assume that the central values of $R_K$ and $R_{K^{\ast}}$ are taken to be unity. We further estimate other unaccounted for SM contributions and show that their inclusion still requires New Physics to fit the data. We then introduce the $g-2$ lepton anomalies as well as the most recent $W$-mass results. Different theoretical models are considered that can explain the discrepancies from the Standard Model. In the final part of our work we estimate the impact of the forthcoming data from LHCb (coming from LHC Run3) and Belle II, when it will have accumulated about $5~ab^{-1}$.

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