arXiv subjects

David Delepine

Publications and source records attributed to David Delepine.

At least 37 records · Page 2Linked to original sources

arXiv2026

Fractional epidemics from quantum loops

Classical compartmental models of epidemiology rely on well-mixed, local interaction approximations that fail to capture the heavy-tailed burst dynamics and long-range spatial correlations observed in real-world outbreaks. While fractional calculus is frequently employed to model these anomalous behaviors, fractional operators are introduced phenomenologically. In this work, we demonstrate that fractional space-time epidemic dynamics emerge naturally and rigorously from first principles using a non-equilibrium quantum field theory model. By mapping the stochastic contagion process to a gauge-mediated field theory via the Doi-Peliti formalism, we go beyond the static mean-field approximation to compute the full dynamical one-loop vacuum polarization. We prove that integrating out a dynamically fluctuating host vacuum generates anomalous momentum and frequency scaling. Transitioning back to coordinate space, this derives a coupled space-time fractional integro-differential equations, where the non-linear transmission vertex is governed by parabolic Riesz potentials and Riemann-Liouville time derivatives. We show that in the anomalous regime ($α< 2$), local Debye screening is modified, facilitating Lévy flight super-spreading and temporal avalanches. Consequently, the effective reproductive number ($R_{eff}$) ceases to be a scalar, transforming into a spectral dispersion relation bounded strictly by the ultraviolet spatial cutoff.

cond-mat.stat-mech↗

arXiv2026

A Universal Convolution-Based Pre-processor to Correct the Prevalence-Incidence Gap in SIR, SEIR, and SIRS Modeling

Traditional compartmental models, including SIR, SEIR, and SIRS frameworks, remain the analytical standard for epidemic forecasting. However, real-world data validation consistently reveals significant predictive failures, such as peak underestimations of up to 50%. This research identifies a persistent fundamental methodological error: the calibration of prevalence-based (stock) models using raw daily incidence (flow) data without proper transformation. We propose an integrated protocol utilizing an exponentially weighted convolution to reconstruct active cases from reported incidence: $I(t) \approx \frac{1}{p} \int_{0}^{t} NDC(τ) e^{-γ(t-τ)} dτ$. This transformation accounts for the recovery rate $γ$ and the ascertainment rate $p$. We demonstrate that increasing structural complexity, such as adding latency (SEIR) or waning immunity (SIRS), fails to resolve the incidence-prevalence gap. Simulation results show that without the proposed universal pre-processor, these advanced models inherit the systematic biases of misaligned data types, leading to significant errors in estimating latent periods and the "heavy tail" of endemicity. The proposed convolution transformation must serve as a universal prerequisite for any compartmental framework, bridging the gap between clinical reporting and mechanistic modeling.

physics.soc-ph↗

arXiv2021

Exploring new physics contributions to $CP$ violation in $τ^- \to K^-π^0ν_τ $

A general analysis of possible violation of CP in processes like $τ\to Kπν$, for unpolarized $τ$ is presented. In this paper, we derive the new contributions to the effective Hamiltonian governs $\vertΔS \vert=1$ semileptonic tau decays in the framework of two Higgs doublet model with generic Yukawa structure and Leptoquarks models. Within these models, we list all operators, in the effective Hamiltonian and provide analytical expression for their corresponding Wilson coefficients. Moreover, we analyze the role of the different contributions, originating from the scalar, vecor and tensor hadronic currents, in generating direct CP asymmetry in the decay rate of $τ^-\to K^-π^0ν_τ$. We show that non vanishing direct CP asymmetry in the decay rate of $τ^-\to K^-π^0ν_τ$ can be generated due to the presence of both, the weak phase in the Wilson coefficient corresponding to the tensor operator and the strong phase difference resulting from the interference between the form factors expressing the matrix elements of the vector and tensor hadronic currents. After taking into account all relevant constraints, we find that the generated direct CP asymmetry is of order $10^{-8}$ which is several orders of magnitude larger than the standard model prediction. We show also that, in two Higgs doublet model with generic Yukawa structure , direct local or non integrated CP violation can be as large as $0.3$ % not far from experimental possibilities. This kind of asymmetry can be generated due to the interference between vector and scalar contributions with different weak phases which is not the case in the SM.

hep-ph↗

arXiv2020

Morphology and numerical characteristics of epidemic curves for SARS-Cov-II using Moyal distribution

In this paper, it is shown that the Moyal distribution is an excelent tool to study the SARS-Cov-II (Covid-19) epidemiological associated curves and its propagation. The Moyal parameters give all the information to describe the form and the impact of the illness outbreak in the different affected countries and its global impact. We checked that the Moyal distribution can accurately fit the daily report of {\it{new confirmed cases of infected people}} (NCC) per country, in that places where the contagion is reaching their final phase, describing the beginning, the most intense phase and the descend of the contagion, simultaneously . In order to achieve the purpose of this work, it is important to work with a complete and well compilated set of the data to be used to fit the curves. Data from European countries like France, Spain, Italy Belgium, Sweden, United Kingdom, Denmark and others like USA and China, have been used. Also, the correlation between the parameters of the Moyal distribution fitting and the general public health measures imposed in each country, have been discussed. A relation between those policies and the features of the Moyal distribution, in terms of their parameters and critical points, is shown; from that, it can be seen that the knowledge of the time evolution of the epidemiological curve, their critical points, superposition properties and rates of the rising and the ending, could help to find a way to estimate the efficiency of social distancing measures, imposed in each country, and anticipate the different phases of the pandemic.

q-bio.PE↗

arXiv2019

New Physics signature in $D^0 (\bar{D}^0)\to f$ effective width asymmetries

Violation of charge conjugation-parity ($\rm CP$) symmetry plays a major rule in the dominance of matter in our universe. A kind of $\rm CP$ violation results from the asymmetry of the life time measured in $M^0$ and $\bar M^0$, here $M$ is a heavy meson, decays to final states which is referred in the literature as $A_Γ^f$. In this paper, we give an estimation of the upper bound on $|A_Γ^f|$ for the Cabibbo Favored $D^0 \rightarrow K^- π^+$ decay process in different models. We show that in the standard model, $|A_Γ^f| \lesssim\mathcal{O} (10^{-10})$. Recently a bound on $A_Γ^f$ has been obtained: $(A^f_Γ)^{Exp.}= (1.6 \pm 1)\times 10^{-4}$. This result motivates further studies on $A_Γ^f$ in beyond standard model physics. In the framework of two Higgs doublet model with generic Yukawa structure, we show that $|A_Γ^{f}|\lesssim \mathcal{O} (10^{-7})$ which is several orders of magnitude smaller than the current experimental value. Finally, in the framework of left-right symmetric models in which the mixing between the left and the right gauge bosons is allowed and the left-right symmetry is not manifest at unification scale, we find that $A_Γ^f$ can be as large as $|A_Γ^f|\lesssim\mathcal{O} (10^{-5})$ which is one order of magnitude smaller than the experimentally measured value by LHCb collaborators.

hep-ph↗

arXiv2019

Direct CP violation in $D^+ \to K^0(\bar K^0) π^+$ decays as a probe for new physics

In this paper we investigate CP violation in charged decays of $D$ meson. Particularly, we study the direct CP asymmetry of the Cabibbo favored non-leptonic $D^+ \rightarrow \bar K^0 π^+$ and the doubly Cabibbo-suppressed decay mode $D^+ \rightarrow K^0 π^+$ within standard model, two Higgs doublet model with generic Yukawa structure and left right symmetric models. In the standard model, we first derive the contributions from box and di-penguin diagrams contributing to their amplitudes which are relevant to the generation of the weak phases essential for non-vanishing direct CP violation. Then, we show that these phases are so tiny leading to a direct CP asymmetry of order $10^{-11}$ in both decay modes. Regarding the two Higgs doublet model with generic Yukawa structure and after taking into account all constraints on the parameter space of the model, we show that the enhanced direct CP asymmetries can be 6 and 7 orders of magnitudes larger than the standard model prediction for $D^+ \rightarrow \bar K^0 π^+$ and $D^+ \rightarrow K^0 π^+$ respectively. Finally, within left right symmetric models, we find that sizable direct CP asymmetry of ${\mathcal O } (10^{-3})$ can be obtained for the decay mode $D^+ \rightarrow \bar K^0 π^+$ after respecting all relevant constraints.

hep-ph↗

arXiv2017

CP violation in $D^0 \to K^+ π^- $

In this paper we study the direct CP asymmetry of the doubly Cabibbo-suppressed decay mode $D^0 \to K^+ π^- $ within standard model and two Higgs doublet model with generic Yukawa structure. In the standard model we derive the corrections to the tree level amplitude, generated from the box and di-penguin diagrams, required for generating the weak CP violating phases. We show that these phases are so tiny leading to a direct CP asymmetry of order $10^{-9}$. Regarding the two Higgs doublet model with generic Yukawa structure we derive the Wilson coefficients relevant to $D^0 \to K^+ π^- $. After taking into account all constraints on the parameter space of the model we show that charged Higgs couplings to quarks can lead to a direct CP asymmetry of order $10^{-3}$ which is $6$ orders of magnitude larger than the standard model prediction.

hep-ph↗

arXiv2015

Effects of an H-mu-tau coupling in quarkonium lepton flavor violation decays

In this work we study the consistency of a possible non-vanishing coupling $Hμτ$ of the order of $3.6\times 10^{-3}$ as pointed recently by the CMS and ATLAS collaborations, with measured lepton flavor violation processes involving quarkonium. We show that the most promising channel to confirm this excess is to look for the lepton flavor tau decay into a $f_0$ and $μ$ where the experimental limit could strongly improved with the new B factories as Belle II.

hep-ph↗

arXiv2014

New Physics effects in D^+ \rightarrow K^- π^+ π^+

In this paper, we study the Cabibbo favored three body non-leptonic D^+ \rightarrow K^- π^+ π^+ decay. We show that the corresponding direct CP asymmetry is so tiny in the framework of the Standard Model and is out of the experimental range. Motivated by this result we extend the study of the CP asymmetry to include a toy model with CP violating weak phase equals 20 degrees in a_2, a model with extra gauge bosons within Left-Right Grand Unification models and a model with charged Higgs boson. We show that the toy model can strongly improve the SM prediction of the CP asymmetry to be about 30%. The largest CP asymmetry can be achieved in the non-manifest Left-Right models where a CP asymmetry up to 25% can be reached. For the two Higgs doublets models the CP asymmetry is of order 10^{-3}.

hep-ph↗

arXiv2012

Observation of CP violation in $D^0 \rightarrow K^- π^+ $ as a smoking gun for New Physics

In this paper, we study the Cabibbo favored non-leptonic $D^0$ decays into $K^- π^+$ decays. First we show that, within the Standard Model, the corresponding CP asymmetry is strongly suppressed and out of the experimental range even taking into account the large strong phases coming from final state Interactions. We show also that although new physics models with extra sequential generation can enhance the CP asymmetry by few orders of magnitude however the resulting CP asymmetry is still far from experimental range. The most sensitive New Physics Models to this CP asymmetry comes from no-manifest Left-Right models where a CP asymmetry up to 10% can be reached and general two Higgs models extension of SM where a CP asymmetry of order $10^{-2}$ can be obtained without being in contradiction with the experimental constraints on these models.

hep-ph↗

arXiv2012

Neutrino Spin Flavor Precession and Leptogenesis

We argue that ΔL=2 neutrino spin flavor precession, induced by the primordial magnetic fields, could have a significant impact on the leptogenesis process that accounts for the baryon asymmetry of the universe. Although the extra galactic magnetic fields is extremely weak at present time (about 10^{-9} Gauss), the primordial magnetic filed at the electroweak scale could be quite strong (of order 10^{17} Gauss). Therefore, at this scale, the effects of the spin flavor precession are not negligible. We show that the lepton asymmetry may be reduced by 50% due to the spin flavor precession. In addition, the leptogenesis will have different feature from the standard scenario of leptogenesis, where the lepton asymmetry continues to oscillate even after the electroweak phase transition.

hep-ph↗

arXiv2011

Supersymmetric contribution to B to rho K and B to pi K^* decays in SCET

We analyze the supersymmetric contributions to the direct CP asymmetries of the decays $B \to πK^*$ and $B\toρK$ within Soft Collinear Effective Theory. We extend the Standard Model analysis of these asymmetries to include the next leading order QCD corrections. We find that, even with QCD correction, the Standard Model predictions can not accommodate the direct CP asymmetries in these decay modes. Using Mass Insertion Approach, we show that non-minimal flavor SUSY contributions mediated by gluino exchange can enhance the CP asymmetries significantly and thus can accommodate the experimental results.

hep-ph↗

arXiv2009

Leptogenesis and Reheating in Complex Hybrid Inflation

We study the transformation into a baryon asymmetry of a charge initially stored in a complex (waterfall) scalar field at the end of a hybrid inflation phase as described in Ref[1]. The waterfall field is coupled to right-handed neutrinos, and is also responsible for their Majorana masses. The charge is finally transferred to the leptons of the Standard Model through the decay of the right-handed neutrinos without introducing new CP violating interactions. Other needed processes, like the decay of the inflaton field and the reheating of the Universe are also discussed in detail.

hep-ph↗

arXiv2009

A new strategy for probing the Majorana neutrino CP violating phases and masses

We propose a new strategy for detecting the CP-violating phases and the effective mass of muon Majorana neutrinos by measuring observables associated with neutrino-antineutrino oscillations in $π^{\pm}$ decays. Within the generic framework of quantum field theory, we compute the non-factorizable probability for producing a pair of same-charged muons in $π^{\pm}$ decays as a distinctive signature of $ν_μ-\bar{ν_μ}$ oscillations. We show that an intense neutrino beam through a long baseline experiment is favored for probing the Majorana phases. Using the neutrino-antineutrino oscillation probability reported by MINOS collaboration, a new stringent bound on the effective muon-neutrino mass is derived.

hep-ph↗

arXiv2009

QFT results for neutrino oscillations and New Physics

The CP asymmetry in neutrino oscillations, assuming new physics at production and/or detection processes, is analyzed. We compute this CP asymmetry using the standard quantum field theory within a general new physics scenario that may generate new sources of CP and flavor violation. Well known results for the CP asymmetry are reproduced in the case of V -A operators, and additional contributions from new physics operators are derived. We apply this formalism to SUSY extensions of the Standard Model where the contributions from new operators could produce a CP asymmetry observable in the next generation of neutrino experiments.

hep-ph↗

arXiv2007

Complex Hybrid Inflation and Baryogenesis

We propose a hybrid inflation model with a complex waterfall field which contains an interaction term that breaks the U(1) global symmetry associated to the waterfall field charge. We show that the asymmetric evolution of the real and imaginary parts of the complex field during the phase transition at the end of inflation translates into a charge asymmetry. The latter strongly depends on the vev of the waterfall field, which is well constrained by diverse cosmological observations.

hep-ph↗

arXiv2007

CP violation in Semi-Leptonic $τ$ decays

We study CP violation in semi-leptonic $τ$ decays and we determine the conditions necessary to be able to define a observable CP asymmetry. We apply these conditions in both models, the standard model for the electroweak interactions and its supersymmetric extensions. In the first case, the leading order contribution to the direct CP asymmetry in $τ^{\pm} \to K^{\pm}π^0 ν_τ$ decay rates is evaluated. In the second case,we compute the SUSY effective hamiltonian that describes the $|ΔS|=1$ semileptonic decays of tau leptons. We show that SUSY contributions may enhance the CP asymmetry of $τ\to K πν_τ$ decays by several orders of magnitude compared to the standard model expectations.

hep-ph↗

arXiv2001

Indirect Bounds on Z-> mu e and Lepton Flavor Violation at Future Colliders

Motivated by the interest in lepton number violating processes, we study the connection between the rate of Z -> mu e decay and those of the low-energy processes mu ->3 e, and mu -> e conversion in nuclear field. We show that if the vector or axial Z form factors are dominant, Br(Z->mu e) is not observable, while if the Z dipole form factors are dominant, the relatively weak indirect bound Br(Z->mu e)<7 10^{-9} does not fully preclude a signal at future colliders, as TESLA. We finally comment on the relation of Z->mu e with Z->tau e and Z->tau mu decays, and suggest a simple scaling law for these three processes.

hep-ph↗