Publications

2025

• Improved phenomenology of $πN$ transition distribution amplitudes
  
  • Pire Bernard
  • Semenov-Tian-Shansky Kirill
  • Sznajder Paweł
  • Szymanowski Lech
  , 2026, 378, pp.05003. To study cross sections and polarization asymmetries for the processes $e p \to e n π^+$ and $e p \to e p π^0$ in the backward region, we develop a flexible phenomenological model for nucleon-to-pion transition distribution amplitudes ($πN$ TDAs), which are used in the QCD collinear factorization description of the scattering amplitudes. Our model is based on the two-component factorized Ansatz for the corresponding spectral densities, quadruple distribution. It takes into account the constraints for $πN$ TDAs arising from the threshold pion production theorem and also includes a forward limit contribution that can be fitted to experimental data. We examine the sensitivity of observable predictions to various modelling assumptions. (10.1051/epjconf/202637805003)
  DOI : 10.1051/epjconf/202637805003
• CTSEG: A segment picture quantum impurity solver based on TRIQS
  
  • Kavokine Nikita
  • Lu Hao
  • Ayral Thomas
  • Ferrero Michel
  • Wentzell Nils
  • Parcollet Olivier
  Journal of Open Source Software, Open Journals, 2025, 10 (109), pp.7425. Electron-electron interactions are a key determinant of the electrical and optical response properties in solid-state materials. Yet, the many-electron problem is outstandingly difficult, and can be tackled analytically only when interactions are weak, or in rare exactly solvable cases. One of the popular numerical schemes for addressing strongly interacting systems is dynamical mean-field theory (DMFT; Georges et al., 1996). In DMFT, the many-body problem formulated on a crystal lattice is self-consistently mapped onto a single atom (or impurity) immersed in an effective environment (or bath). The remaining computational task is then the solution of the impurity problem, which can be carried out through various quantum Monte Carlo algorithms (Gull et al., 2011). Here, we present an implementation of the continous time hybridization expansion algorithm in the segment picture (CTSEG) based on TRIQS, a comprehensive library for the numerical investigation of interacting quantum systems (Parcollet et al., 2015). (10.21105/joss.07425)
  DOI : 10.21105/joss.07425
• Prequantisation from the path integral viewpoint
  
  • Horváthy P A
  , 2025. <div><p>The quantum mechanically admissible definitions of the factor exp (i/ℏ)S(γ) in the Feynman integral are put in bijection with the prequantisations of Kostant and Souriau. The different allowed expressions of this factor -the inequivalent prequantisations -are classified. The theory is illustrated by the Aharonov-Bohm experiment and by identical particles.</p></div>
• Carrollian-holographic Derivation of BMS Flux-balance Laws
  
  • Fiorucci Adrien
  • Pekar Simon
  • Marios Petropoulos P
  • Vilatte Matthieu
  , 2025. We demonstrate that the BMS evolution equations for the mass and angular momentum aspects in asymptotically flat Einstein gravity follow from local Carroll, Weyl, and diffeomorphism invariance at the null conformal boundary, upon providing a minimalistic holographic dictionary as the sole input from the bulk. This result is a significant step in the quest for a flat-space holographic correspondence and offers a geometric implementation of the radiative degrees of freedom that source the boundary theory in the presence of bulk gravitational waves.
• The Ubiquity of Twisted Flux Ropes in the Quiet Sun
  
  • Amari Tahar
  • Canou Aurélien
  • Velli Marco
  • Mikic Zoran
  • Alauzet Frederic
  • Buchlin Eric
  • Luciani Jean-François
  • Aly Jean-Jacques
  • Tarr Lucas
  The Astrophysical Journal Letters, Bristol : IOP Publishing, 2025, 984 (1), pp.L37. Abstract Models and observations have demonstrated that twisted flux ropes (TFRs) play a significant role in the structure and eruptive dynamics of active regions. Their role in the dynamics of the quiet Sun atmosphere has remained elusive, their fundamental relevance emerging mainly from theoretical models showing that they form and erupt as a result of flux cancellation. Here, Hinode high-resolution photospheric vector magnetic field measurements are integrated with advanced environment reconstruction models: TFRs develop on various scales and are associated with the appearance of mesospots. The developing TFRs contain sufficient free magnetic energy to match the requirements of the recently observed “campfires” discovered by Solar Orbiter in the quiet Sun. The free magnetic energy is found to be large enough to trigger eruptions, while the magnetic twist is large enough to trigger confined eruptions, heating the chromosphere. TFRs are also connected to larger-scale magnetic fields such as supergranulation loops, allowing the generation of Alfvén waves at the top of the chromosphere that can propagate along them. High-resolution magnetohydrodynamic simulations, incorporating subsurface dynamo activity at an unprecedented 30 km spatial resolution, confirm that TFRs are ubiquitous products of the permanent small-scale dynamo engine that feeds their formation, destabilization, eruption via flux emergence, submergence, and cancellation of their chromospheric feet, similar to the dynamics driving large-scale eruptive events. Future investigations, especially with the Daniel K. Inouye Solar Telescope and Solar Orbiter, will deepen our understanding of TFRs in the context of atmospheric heating. (10.3847/2041-8213/adb74f)
  DOI : 10.3847/2041-8213/adb74f
• Timelike Compton scattering on a spin-0 target with kinematic twist-4 precision
  
  • Martinez-Fernandez V.
  • Pire B.
  • Sznajder P.
  • Wagner J.
  Physical Review D, American Physical Society, 2025, 111 (7), pp.074034. We calculate the kinematic twist-3 and 4 corrections to the leading order amplitude of timelike Compton scattering (TCS) on a (pseudo-)scalar target, in the recently developed framework based on the conformal operator-product expansion. This allows us to compute the complete set of helicity amplitudes of the process, in particular those that vanish at leading twist. We compare the effects of higher twist contributions to TCS with those in deeply virtual Compton scattering (DVCS). Our estimates, based on a $\pi$-meson GPD model, indicate that these contributions are sizeable and will play a crucial role in the interpretation of data from current and forthcoming experiments.
• Timelike Compton scattering on a spin-0 target with kinematic twist-4 precision
  
  • Martínez-Fernández V.
  • Pire B.
  • Sznajder P.
  • Wagner J.
  Physical Review D, American Physical Society, 2025, 111 (7), pp.074034. We calculate the kinematic twist-3 and twist-4 corrections to the leading-order amplitude of timelike Compton scattering (TCS) on a (pseudo)scalar target, in the recently developed framework based on the conformal operator-product expansion. This allows us to compute the complete set of helicity amplitudes of the process, in particular those that vanish at leading twist. We compare the effects of higher-twist contributions to TCS with those in deeply virtual Compton scattering. Our estimates, based on a $pi$-meson GPD model, indicate that these contributions are sizeable and will play a crucial role in the interpretation of data from current and forthcoming experiments. (10.1103/PhysRevD.111.074034)
  DOI : 10.1103/PhysRevD.111.074034
• French HEP community input to the European Strategy for Particle Physics
  
  • Amhis Yasmine
  • Andrea Jeremy
  • Augé Etienne
  • Bolognesi Sara
  • Boonekamp Maarten
  • Calvet Samuel
  • Chapon Emilien
  • Contardo Didier
  • Couderc Fabrice
  • Crépé-Renaudin Sabine
  • D'Eramo Louis
  • Diaconu Cristinel
  • Dujany Giulio
  • Ferri Federico
  • Genest Marie-Hélène
  • Lavignac Stéphane
  • Levêque Jessica
  • Marquet Cyrille
  • Meregaglia Anselmo
  • Monteil Stephane
  • Muñoz Camacho Carlos
  • Portales Louis
  • Schwemling Philippe
  • Smith Christopher
  • Teixeira Ana M
  • Winn Michael
  , 2025. In view of the European Strategy for Particle Physics process, the French HEP community has organized a national process of collecting written contributions and has pursued a series of workshops culminating with a national symposium held in Paris on January 20-21, 2025 that involved over 280 scientists https://indico.in2p3.fr/event/34662/. The present document summarises the main conclusions of this bottom-up approach centred on the physics and technology motivations.
• Majorana bound states from cavity embedding in an interacting two-site Kitaev chain
  
  • Gómez-León Álvaro
  • Schirò Marco
  • Dmytruk Olesia
  Physical Review B, American Physical Society, 2025, 111 (15), pp.155410. Poor man's Majorana Bound States (MBS) arise in minimal Kitaev chains when the parameters are fine-tuned to a sweet spot. We consider an interacting two-site Kitaev chain coupled to a singlemode cavity and show that the sweet spot condition can be controlled with the cavity frequency and the hopping between sites. Furthermore, we demonstrate that photon-mediated effective interactions can be used to screen intrinsic interactions, improving the original quality of the MBS. We describe experimental signatures in the cavity transmission to detect their presence and quality. Our work proposes a new way to tune poor man's MBS in a quantum dot array coupled to a cavity. (10.1103/PhysRevB.111.155410)
  DOI : 10.1103/PhysRevB.111.155410
• Algorithm for computing perturbation series of dynamical mean field theory
  
  • Bertrand Corentin
  • Ferrero Michel
  • Parcollet Olivier
  Physical Review B, American Physical Society, 2025, 111 (16), pp.165120. We show how to use diagrammatic techniques to compute the weak-coupling perturbation series of the self-consistent solution to a Dynamical Mean Field Theory (DMFT) problem. This approach constitutes an alternative to using diagrammatic techniques directly as an impurity solver. It allows one to bypass the need of multiple perturbative series resummations within the DMFT self-consistency loop. It can be applied at or out of equilibrium, with any diagrammatic formalism, such as real times, imaginary times, or Matsubara frequencies formalisms. As a proof of principle, we illustrate our method with the half-filled Hubbard model on the Bethe lattice in the DMFT approximation, using Quantum Quasi-Monte Carlo (QQMC) to obtain the impurity perturbation series on the real time axis. (10.1103/PhysRevB.111.165120)
  DOI : 10.1103/PhysRevB.111.165120
• Effective tight-binding models in optical moiré potentials
  
  • Johnstone Dean
  • Mishra Shanya
  • Zhu Zhaoxuan
  • Sanchez-Palencia Laurent
  Physical Review A, American Physical Society, 2025, 111 (4), pp.043305. <div><p>A twist between two periodic systems offers the possibility to drastically control quantum transport properties. At discrete sets of commensurate twisting angles, a moiré periodic pattern is formed, and the low energy single-particle spectrum forms distinct bands and gaps. Here, we consider twisted systems at a commensurate angle made of two continuous-space periodic potentials. We devise a general approach, based on a hierarchy of energy scales, to derive effective tight-binding models that capture the energy spectrum, focusing on the case of square lattices. Localized states in the moiré unit cell are coupled by strong intra-cell and weak inter-cell tunnellings, generating a series of energy bands and sub-bands that correspond to distinct, periodic lattices. For sufficiently deep potentials, we find excellent agreement between the spectrum of the continuous-space system and the tight-binding approximation thus constructed. Our approach allows for the interpretation of moiré bandstructures and the extraction of parameters for the effective tight-binding models. Applications to the physics of many-body systems and extensions to other twisted models are also discussed.</p></div> <div>Class III Bands</div> (10.1103/PhysRevA.111.043305)
  DOI : 10.1103/PhysRevA.111.043305
• Linear and nonlinear supersymmetry in field and string theory
  
  • Casagrande Gabriele
  , 2025. The current state of high-energy physics is characterized by a division into two distinct branches. On one side, we have the Standard Model of particle physics, which has been tested with great precision and confirmed as the theory describing the physics at the TeV scale. On the other side, it is clear that this theory is incomplete. First, it must be coupled to gravity, following the principles of Einstein's general relativity. Second, a quantum description of gravitational interactions must be developed, just as with all other forces. The only example that has consistently realized this unification so far is String Theory, which lives near the Planck scale. Following the effective field theory paradigm, one expects these two branches - string theory in the UV and the Standard Model in the IR of the energy spectrum - to be linked through a series of lower-energy effective models, each associated with a specific energy scale between the TeV and the Planck mass, gradually revealing the features of the quantum theory of gravity. However, how to explicitly realize this connection is far from clear and well-understood.Bridging this gap is one of the main challenges of modern days high-energy physics. In this respect, a crucial role is played by supersymmetry. The reason is that supersymmetry has strong motivations to be realized on both branches of the energy spectrum we seek to connect. On the field theory side, it represents the only possible extension of the Poincare group, and its realization as a local symmetry automatically yields the gravitational interaction. On the string side, it is an essential element of the worldsheet theory in order to describe fermionic excitations and to ensure the stability of string vacua, and, moreover, the field theory limit of such superstring theories are supergravity theories. In addition, supersymmetry provides also with a well-defined framework in which to embed the effective flow from String Theory to the Standard Model. Being the latter obviously non-supersymmetric, supersymmetry must be spontaneously broken at some stage, and the scale of supersymmetry breaking becomes the vehicle with which the UV physics propagates at lower energies.In this thesis we investigate effective field and string theories, in which supersymmetry is realized - and broken - in different ways. The first construction of this type that we present are effective theories with nonlinearly realized supersymmetry, obtained through the formalism of constrained superfields. We prove a criterion to identify inconsistent constraints, we formulate, their improved version, and propose, along these lines, improved supergravity models of inflation. Then, we discuss a peculiar phenomenological application of such a framework, the gravitational production of massive gravitinos in time-dependent backgrounds, highlighting some physical subtleties of its standard description, particularly severe in the case of the gravitino.The focus moves then to pure supergravity in four dimensions. In this context, we analyze the leading-order coupling to supergravity of the rigid multiplet of the massive spin-2 field, by means of the supercurrent superfield formalism. The result of our analysis is that there exist a single consistent class of such couplings. This is fundamentally distinct from the one obtained by compactifying higher-dimensional supergravity, and it is interestingly associated to the highest-possible cutoff scale that these effective theories can reach.Finally, we consider type II B string theory and construct a novel orientifold projection, of the Scherk-Schwarz type, which breaks supersymmetry entirely. The salient features of this theory are that the O-planes couple only to the twisted sector and that it is invariant under S-duality, which can be interpret as the result of an F-theory compactification. We also construct the D-branes spectrum, analyze their stability, and compare with previous similar constructions. (10.70675/39673729za6b2z4ff7za756za06fa58564cd)
  DOI : 10.70675/39673729za6b2z4ff7za756za06fa58564cd
• Scattering from an external field in quantum chromodynamics at high energies: From foundations to interdisciplinary connections
  
  • Angelopoulou Athanasia-Konstantina
  • Le Anh Dung
  • Munier Stéphane
  SciPost Physics Lecture Notes, SciPost, 2025, pp.92. We review the factorization of the S S -matrix elements in the context of particle scattering off an external field, which can serve as a model for the field of a large nucleus. The factorization takes the form of a convolution of light cone wave functions describing the physical incoming and outgoing states in terms of bare partons, and products of Wilson lines. The latter represent the interaction between the bare partons and the external field. Specializing to elastic scattering amplitudes of onia at very high energies, we introduce the color dipole model, which formulates the calculation of the modulus-squared of the wave functions in quantum chromodynamics with the help of a branching random walk, and the scattering amplitudes as observables on this classical stochastic process. Methods developed for general branching processes produce analytical formulas for the asymptotics of such observables, and thus enable one to derive exact large-rapidity expressions for onium-nucleus cross sections, from which electron-nucleus cross sections may be inferred. (10.21468/SciPostPhysLectNotes.92)
  DOI : 10.21468/SciPostPhysLectNotes.92
• Efficiency of neural quantum states in light of the quantum geometric tensor
  
  • Dash Sidhartha
  • Gravina Luca
  • Vicentini Filippo
  • Ferrero Michel
  • Georges Antoine
  Communications Physics, Nature Research, 2025, 8 (1), pp.92. Neural quantum state (NQS) ans\"atze have shown promise in variational Monte Carlo algorithms by their theoretical capability of representing any quantum state. However, the reason behind the practical improvement in their performance with an increase in the number of parameters is not fully understood. In this work, we systematically study the efficiency of restricted Boltzmann Machines (RBMs) to represent the ground states in different phases of the spin-1 bilinear-biquadratic model, as the hidden layer density $\alpha$ increases. We train our ansatz by minimizing two different loss functions: 1) energy, and 2) infidelity of the NQS ansatz w.r.t. that of the exact ground state. We observe that the accuracy of our ansatz saturates with $\alpha$ in both cases. We demonstrate that this can be explained by looking at the spectrum of the quantum geometric tensor (QGT). We find that the rank of the QGT saturates beyond a certain $\alpha$, and we emphasize that it corresponds to the \textit{dimension of the relevant manifold} for an optimized NQS. This provides a useful diagnostics for the practical representation power of an NQS ansatz. (10.1038/s42005-025-02005-4)
  DOI : 10.1038/s42005-025-02005-4
• The electronic structure, crystal fields, and magnetic anisotropy in RECo5 magnets
  
  • Zhang Zhen
  • Kutepov Andrey
  • Pourovskii Leonid
  • Antropov Vladimir
  AIP Advances, American Institute of Physics- AIP Publishing LLC, 2025, 15 (3). The current progress in describing rare-earth-based magnets' electronic structure and magnetic properties is discussed. We use several currently popular electronic structure methods to show the typical values of critical parameters that define the physics of RECo5 (RE = rare earth atom) materials. The magnetic moments and magnetic anisotropy of 4f atoms are obtained using several approaches, including anisotropic 4f-charge density-constrained DFT and DFT+HI methods. We also suggest the introduction of "penalty" functional for obtaining correct variational total energy in the traditional Hund's rule-constrained DFT-based techniques. The applicability and future extensions are discussed. The proposed combination of methods is potentially suitable for high-throughput computational searches of new rare-earth-containing magnetic materials. (10.1063/9.0000877)
  DOI : 10.1063/9.0000877
• A unique coupling of the massive spin-2 field to supergravity
  
  • Bossard Guillaume
  • Casagrande Gabriele
  • Dudas Emilian
  • Loty Adrien
  , 2025. We show that the coupling of a massive spin-2 field to undeformed N=1 supergravity in four dimensions is unique, leading to a specific non-minimal coupling to the Riemann tensor. The massive spin-2 coupling reproduces the one of an oscillator mode in open string theory, while the massive spin-1 coupling includes a higher-derivative term that is expected to violate causality in the background of a gravitational shock wave. We argue that the resolution of causality and the unitarity bound in the Regge limit require the introduction of infinitely many higher-spin fields similar to the Regge trajectories in string theory, therefore providing an argument in favour of the string lamppost principle with minimal supersymmetry in four dimensions. To obtain this result, we construct the general stress-energy tensor multiplet for the massive spin-2 multiplet with N=1 supersymmetry.
• Observation of ponderomotively driven bow shock using Thomson scattering
  
  • Milder A L
  • Bruulsema C
  • Hüller S
  • Walsh C
  • Rozmus W
  • Yin L
  • Ludwig J
  • Farmer W A
  • Albright B J
  • Rose H A
  • Swadling G
  Physical Review Research, American Physical Society, 2025, 7, pp.013163. <div><p>High energy speckled lasers are known to exert ponderomotive forces on a plasma, this can reduce flow transverse to the propagation of the beams. When coupled with a supersonic flow, this has been shown to lead to formation of a shock that travels against the flow. Experiments conducted on the OMEGA laser facility have used Thomson scattering to observe density and velocity changes consistent with this ponderomotively driven shock. Comparisons of the data with hydrodynamic simulations with the ponderomotive force, particle-in-cell simulations with a full Maxwell field solver, and hydrodynamic simulations without the ponderomotive force show that this shock feature is only reproduced with accounting for the ponderomotive force.</p></div> (10.1103/PhysRevResearch.7.013163)
  DOI : 10.1103/PhysRevResearch.7.013163
• Twisted orientifold planes and S-duality without supersymmetry
  
  • Bossard Guillaume
  • Casagrande Gabriele
  • Dudas Emilian
  Journal of High Energy Physics, Springer, 2025, 2025 (2), pp.62. We show that the coupling of a massive spin-2 field to undeformed N = 1 supergravity in four dimensions is unique, leading to a specific non-minimal coupling to the Riemann tensor. The massive spin-2 coupling reproduces the one of an oscillator mode in open string theory, while the massive spin-1 coupling includes a higher-derivative term that is expected to violate causality in the background of a gravitational shock wave. We argue that the resolution of causality and the unitarity bound in the Regge limit require the introduction of infinitely many higher-spin fields similar to the Regge trajectories in string theory, therefore providing an argument in favour of the string lamppost principle with minimal supersymmetry in four dimensions. To obtain this result, we construct the general stress-energy tensor multiplet for the massive spin-2 multiplet with N = 1 supersymmetry. (10.1007/JHEP02(2025)062)
  DOI : 10.1007/JHEP02(2025)062
• Magnetic phase diagram of the three-dimensional doped Hubbard model
  
  • Rampon Liam
  • Šimkovic Fedor
  • Ferrero Michel
  Physical Review Letters, American Physical Society, 2025, 134 (6), pp.066502. We establish the phase diagram of the Hubbard model on a cubic lattice for a wide range of temperatures, dopings and interaction strengths, considering both commensurate and incommensurate magnetic orders. We use the dynamical mean-field theory together with an efficient method to compute the free energy which enable the determination of the correct ordering vectors. Besides an antiferromagnetic state close to half-filling, we identify a number of different magnetic spiral phases with ordering vectors $(q,\pi,\pi)$, $(q,q,\pi)$ and $(q,q,q)$ as well as a region with close competition between them, hinting at spatial phase separation or at the onset of a stripe phase. Additionally, we extensively study several thermodynamic properties with direct relevance to cold-atom experiments: the entropy, energy and double-occupancy. (10.1103/PhysRevLett.134.066502)
  DOI : 10.1103/PhysRevLett.134.066502
• Stabilité d'écoulements d'intérêt pour la fusion par confinement inertiel : perturbations optimales
  
  • Thiriet Jean-Gabriel
  , 2025. La fusion par confinement inertiel (FCI) vise à déclencher des réactions de fusion thermonucléaire en implosant une capsule sphérique à l'aide d'un rayonnement intense. Le développement d'instabilités hydrodynamiques pendant l’implosion en dégrade la symétrie et reste le principal obstacle au déclenchement de ces réactions. De nombreux efforts ont été déployés au cours des dernières décennies pour capturer les instabilités hydrodynamiques les plus dangereux pour la FCI. Deux approches sont classiquement mises en oeuvre dans l'analyse de ces instabilités : l'étude de l'amplification temporelle de perturbations initiales ou aux limites bien choisies et l'étude des mécanismes physiques en jeu au cours de phases élémentaires de l'implosion (écoulement d'ablation, d'onde de choc, d'onde de détente, etc) ou pour des modèles simplifiés d'implosion. Bien que ces approches aient permis une meilleure compréhension des instabilités hydrodynamiques en FCI, elles restent incomplètes et sont susceptibles de ne pas capturer des perturbations qui pourraient s'avérer critique pour l'écoulement. La nature transitoire des phénomènes hydrodynamiques et la durée finie d'une implosion soulignent la nécessité d'analyses en temps courts de perturbations. L'analyse non-modale de stabilité hydrodynamique répond à ce besoin en permettant l'identification systématique de dynamiques transitoires de perturbations via la recherche de perturbations optimales initiales ou de frontières. Dans une étude précédente, une recherche de perturbations initiales optimales a permis d'identifier des croissances transitoires dominantes de perturbations linéaires dans un écoulement d'ablation (Varillon, 2019).Dans ce travail, nous élargissons cette analyse non-modale de stabilité linéaire à d'autres écoulements d'intérêts en FCI (onde de détente, compression homogène isentropique) et au problème de perturbations optimales de frontières. Les caractères non-stationnaire, compressible, stratifié de ces écoulements et les déformations de leur frontières posent autant de difficultés. Dans ce cadre une analyse de stabilité non-modale requiert une méthode d'optimisation de type direct-adjoint. La formulation des équations adjointes est établie ici par la méthode de dualité, corroborant celle précédemment obtenue par la méthode des mulitplicateurs de Lagrange. Une recherche de perturbations initiales optimales est mise en oeuvre pour une compression homogène isentropique mettant en lumière des croissances transitoires dans l'écoulement due à la propagation d'ondes acoustiques. La méthode d'optimisation de perturbations de frontières est d'abord illustrée dans le cas de la perturbation de la tête d'une onde de détente isentropique. En particulier, l'épaisseur de la détente et la longueur d'onde transverse de la perturbation jouent un rôle déterminant dans l'amplification des perturbations. Enfin cette méthode est appliquée à la recherche de perturbations optimales au front de choc amont d'une onde d'ablation auto-semblable. (10.70675/1173bd34z805ez49d5z86f8z9b6b1de76247)
  DOI : 10.70675/1173bd34z805ez49d5z86f8z9b6b1de76247
• Back-to-back dijet production in DIS at next-to-eikonal accuracy and twist-3 gluon TMDs
  
  • Altinoluk Tolga
  • Beuf Guillaume
  • Czajka Alina
  • Marquet Cyrille
  Physical Review D, American Physical Society, 2025. 38 pages (10.1103/PhysRevD.111.014010)
  DOI : 10.1103/PhysRevD.111.014010
• Universal Waterfall Feature in Cuprate Superconductors: Evidence of a Momentum-Driven Crossover
  
  • Bacq-Labreuil Benjamin
  • Fawaz Chafic
  • Okazaki Yuichi
  • Obata Yukiko
  • Cercellier Hervé
  • Lefevre Patrick
  • Bertran François
  • Santos-Cottin David
  • Yamamoto Hajime
  • Yamada Ikuya
  • Azuma Masaki
  • Horiba Koji
  • Kumigashira Hiroshi
  • d'Astuto Matteo
  • Biermann Silke
  • Lenz Benjamin
  Physical Review Letters, American Physical Society, 2025, 134, pp.016502. We study two related universal anomalies of the spectral function of cuprates, so called waterfall and high-energy kink features, by a combined cellular dynamical mean-field theory and angle-resolved photoemission study for the oxychloride Na$_x$Ca$_{2-x}$CuO$_2$Cl$_2$ (Na-CCOC). Tracing their origin back to an interplay of spin-polaron and local correlation effects both in undoped and hole-doped (Na-)CCOC, we establish them as a universal crossover between regions differing in the momentum dependence of the coupling and not necessarily in the related quasiparticles' energies. The proposed scenario extends to doping levels coinciding with the cuprate's superconducting dome and motivates further investigations of the fate of spin-polarons in the superconducting phase. (10.1103/PhysRevLett.134.016502)
  DOI : 10.1103/PhysRevLett.134.016502
• Numerical study of Darcy's law of yield stress fluids on a deep tree-like network
  
  • Munier Stéphane
  • Rosso Alberto
  Journal of Statistical Mechanics: Theory and Experiment, IOP Publishing, 2025, 2025 (1), pp.013301. Understanding the flow dynamics of yield stress fluids in porous media presents a substantial challenge. Both experiments and extensive numerical simulations frequently show a non-linear relationship between the flow rate and the pressure gradient, deviating from the traditional Darcy law. In this article, we consider a tree-like porous structure and utilize an exact mapping with the directed polymer (DP) with disordered bond energies on the Cayley tree. Specifically, we adapt an algorithm recently introduced by Brunet et al. [Europhys. Lett. 131, 40002 (2020)] to simulate exactly the tip region of branching random walks with the help of a spinal decomposition, to accurately compute the flow on extensive trees with several thousand generations. Our results confirm the asymptotic predictions proposed by Schimmenti et al. [Phys. Rev. E 108, L023102 (2023)], tested therein only for moderate trees of about 20 generations. (10.1088/1742-5468/ad9c4d)
  DOI : 10.1088/1742-5468/ad9c4d
• Visions in Quantum Gravity
  
  • Buoninfante Luca
  • Knorr Benjamin
  • Kumar K. Sravan
  • Platania Alessia
  • Anselmi Damiano
  • Basile Ivano
  • Bjerrum-Bohr N.Emilj
  • Brandenberger Robert
  • Carrillo González Mariana
  • Davis Anne-Christine
  • Dittrich Bianca
  • Di Vecchia Paolo
  • Donoghue John F
  • Dowker Fay
  • Dvali Gia
  • Eichhorn Astrid
  • Giddings Steven B
  • Gnecchi Alessandra
  • Gubitosi Giulia
  • Heisenberg Lavinia
  • Kallosh Renata
  • Koshelev Alexey S
  • Liberati Stefano
  • Modesto Leonardo
  • Moniz Paulo
  • Oriti Daniele
  • Papadoulaki Olga
  • Pawlowski Jan M
  • Percacci Roberto
  • Rachwał Lesław
  • Sakellariadou Mairi
  • Salvio Alberto
  • Stelle Kellogg
  • Surya Sumati
  • Tseytlin Arkady
  • Turok Neil
  • van Riet Thomas
  • Woodard Richard P
  SciPost Phys.Comm.Rep., 2025, pp.11. To deepen our understanding of Quantum Gravity and its connections with black holes and cosmology, building a common language and exchanging ideas across different approaches is crucial. The Nordita Program "Quantum Gravity: from gravitational effective field theories to ultraviolet complete approaches" created a platform for extensive discussions, aimed at pinpointing both common grounds and sources of disagreements, with the hope of generating ideas and driving progress in the field. This contribution summarizes the twelve topical discussions held during the program and collects individual thoughts of speakers and panelists on the future of the field in light of these discussions. (10.21468/SciPostPhysCommRep.11)
  DOI : 10.21468/SciPostPhysCommRep.11
• Magnetic Anti-de Sitter Wormholes as seeds for Higgs Inflation
  
  • Betzios Panos
  • Gialamas Ioannis D
  • Papadoulaki Olga
  Physical Review D, American Physical Society, 2025, 111 (12), pp.123542. We show how certain types of magnetic asymptotically Anti-de Sitter Euclidean wormholes can catalyze the onset of inflation. These wormholes can be embedded as saddle point solutions of General Relativity coupled to the Standard Model, the inflaton being identified with the Higgs particle. Our scenario is based on the assumption that the quantum effective potential for the Higgs turns negative at a certain high energy window, in line with current measured values for the Higgs and Top quark masses. Within our proposal, we can estimate various parameters and physical quantities of interest, in consistency with current observational bounds. (10.1103/9w85-fyhs)
  DOI : 10.1103/9w85-fyhs