Publications

2025

• Using the $W$ as a Standard Candle to Reach the Top: Calibrating Energy Correlator Based Top Mass Measurements
  
  • Holguin Jack
  • Moult Ian
  • Pathak Aditya
  • Procura Massimiliano
  • Schöfbeck Robert
  • Schwarz Dennis
  Physical Review Letters, American Physical Society, 2025, 134 (23), pp.368. The top quark mass plays a central role in our understanding of the Standard Model and its extrapolation to high energies. However, precision measurements of the top quark mass at hadron colliders are notoriously difficult, motivating the development of qualitatively new approaches to take advantage of the enormous datasets of top quarks at the Large Hadron Collider (LHC). Recent advances in jet substructure have enabled the precise theoretical description of angular correlations in energy flux. However, their application to precision mass measurements is less direct since they measure a dimensionless angular scale. Inspired by the use of standard candles in cosmology, we introduce a single energy correlator-based observable that reflects the characteristic angular scales of both the $W$-boson and the top quark masses. This gives direct access to the dimensionless quantity $m_{t}/m_{W}$, from which $m_{t}$ can be extracted in a well-defined short-distance mass scheme as a function of the well-known $m_{W}$ (our LHC Cepheid variable). We perform a Monte-Carlo-based study to demonstrate the properties of our observable and the statistical feasibility of its extraction from the Run 2 and 3 and High-Luminosity LHC data sets. The resulting $m_t$ has remarkably small uncertainties from non-perturbative effects and is insensitive to the parton distribution functions. We believe that our proposed observable provides a road map for a rich program to achieve a record precision top quark mass measurement at the LHC. (10.1103/j4sp-fcmd)
  DOI : 10.1103/j4sp-fcmd
• Physics case for quarkonium studies at the Electron Ion Collider
  
  • Boer Daniël
  • Flett Chris A
  • Flore Carlo
  • Kikoła Daniel
  • Lansberg Jean-Philippe
  • Nefedov Maxim
  • van Hulse Charlotte
  • Bhattacharya Shohini
  • Bor Jelle
  • Butenschoen Mathias
  • Ceccopieri Federico
  • Chen Longjie
  • Cheung Vincent
  • d'Alesio Umberto
  • Echevarria Miguel
  • Hatta Yoshitaka
  • Hyde Charles E
  • Kishore Raj
  • Kosarzewski Leszek
  • Lorcé Cédric
  • Li Wenliang
  • Li Xuan
  • Maxia Luca
  • Metz Andreas
  • Mukherjee Asmita
  • Muñoz Camacho Carlos
  • Murgia Francesco
  • Nadel-Turonski Pawel
  • Pisano Cristian
  • Qiu Jian-Wei
  • Rajesh Sangem
  • Rinaldi Matteo
  • Rittenhouse West Jennifer
  • Saleev Vladimir
  • Santiesteban Nathaly
  • Setyadi Chalis
  • Taels Pieter
  • Tu Zhoudunmin
  • Vitev Ivan
  • Vogt Ramona
  • Watanabe Kazuhiro
  • Yao Xiaojun
  • Yedelkina Yelyzaveta
  • Yoshida Shinsuke
  Prog.Part.Nucl.Phys., 2025, 142, pp.104162. The physics case for quarkonium-production studies accessible at the US Electron Ion Collider is described. (10.1016/j.ppnp.2025.104162)
  DOI : 10.1016/j.ppnp.2025.104162
• String Theory in a Pinch: Resolving the Gregory-Laflamme Singularity
  
  • Emparan Roberto
  • Sanchez-Garitaonandia Mikel
  • Tomašević Marija
  Journal of High Energy Physics, Springer, 2025, 02, pp.104. Thin enough black strings are unstable to growing ripples along their length, eventually pinching and forming a naked singularity on the horizon. We investigate how string theory can resolve this singularity. First, we study the string-scale version of the static non-uniform black strings that branch off at the instability threshold: "string-ball strings", which are linearly extended, self-gravitating configurations of string balls obtained in the Horowitz-Polchinski (HP) approach to near-Hagedorn string states. We construct non-uniform HP strings in spatial dimensions $d\leq 6$ and show that, as the inhomogeneity increases, they approach localized HP balls. By examining the thermodynamic properties of the different phases in the canonical and microcanonical ensembles, we find that, for a given mass, the uniform HP string will not evolve into a non-uniform or localized configuration. Building on these results and independent evidence from the evolution of the black string instability with $\alpha'$ corrections, we propose that string theory slows and eventually halts the pinching evolution at a classically stable stringy neck, with details depending on the dimension $d$. The system then enters a slower phase in which the neck gradually evaporates into radiation. We discuss this scenario as a framework for understanding how string theory resolves the formation of naked singularities. (10.1007/JHEP02(2025)104)
  DOI : 10.1007/JHEP02(2025)104
• Accessing Generalized Parton Distributions through 2 to 3 exclusive processes
  
  • Duplančić Goran
  • Nabeebaccus Saad
  • Passek-K. Kornelija
  • Pire Bernard
  • Szymanowski Lech
  • Wallon Samuel
  PoS - Proceedings of Science, SISSA, 2025, DIS2024, pp.228. We review our results on a new class of 2 to 3 exclusive processes, as a probe of both chiral-even and chiral-odd quark GPDs. We consider the exclusive photoproduction of a photon-meson pair, in the kinematics where the pair has a large invariant mass, described in the collinear factorization framework. We cover the whole kinematical range from medium energies in fixed target experiments to very large energies of colliders, by considering the experimental conditions of JLab 12-GeV, COMPASS, future EIC and LHC (in ultra-peripheral collisions) cases. Our analysis covers neutral and charged rho-mesons, as well as charged pions. The case of the rho-meson, depending on its polarization, provides access to either chiral-even or chiral-odd GPDs, at leading twist. We find that the order of magnitude of the obtained cross sections are sufficiently large for a dedicated experimental analysis to be performed, especially at JLab. Furthermore, we compute the linear photon beam polarization asymmetry, which we find to be sizeable, in the case of a longitudinally polarized $\rho$-meson or of a charged pion. These predictions are obtained for both asymptotic distribution amplitude (DA) and holographic DA. (10.22323/1.469.0228)
  DOI : 10.22323/1.469.0228
• Direct measurement of Tan's contact in a one-dimensional Lieb-Liniger gas
  
  • Huang Qi
  • Yao Hepeng
  • Chen Xuzong
  • Sanchez-Palencia Laurent
  Sci.Adv., 2025, 11 (40), pp.adv3727. The Tan contact has emerged as a pivotal quantity in characterizing many-body quantum systems, bridging microscopic short-range correlations to thermodynamic behavior. It is defined as the weight of universal $1/k^4$ fall off in momentum distribution tails, which can be measured directly in ultracold gases. So far, however, its direct measurement has been hindered in Bose gases due to interactions strongly affecting the expansion dynamics. Here, we present the first direct measurement of the Tan contact in a strongly-correlated Lieb-Liniger gas. Leveraging the one-dimensional geometry of our system, we implement a two-stage expansion scheme, yielding interaction-immune time-of-flight imaging. Our results show excellent agreement with theoretical predictions from quantum Monte Carlo calculations, which also provides independent thermometry of the experiment. By varying atom number, temperature, and interaction strength, we obtain results consistent with the universal scaling law predicted for the trapped Lieb-Liniger model. Our work paves the way for further characterization of the Lieb-Liniger gas across broad interaction regimes and holds promise for extension to other correlated quantum gases in confined geometries. (10.1126/sciadv.adv3727)
  DOI : 10.1126/sciadv.adv3727
• Hund flat band in a frustrated spinel oxide
  
  • Oh Dongjin
  • Hampel Alexander
  • Wakefield Joshua P
  • Moen Peter
  • Smit Steef
  • Luo Xiangyu
  • Zonno Marta
  • Gorovikov Sergey
  • Leandersson Mats
  • Polley Craig
  • Kundu Asish K
  • Rajapitamahuni Anil
  • Vescovo Elio
  • Jozwiak Chris
  • Bostwick Aaron
  • Rotenberg Eli
  • Isobe Masahiko
  • Verma Manish
  • Crispino Matteo
  • Grundner Martin
  • Kugler Fabian B
  • Parcollet Olivier
  • Schollwöck Ulrich
  • Takagi Hidenori
  • Damascelli Andrea
  • Sangiovanni Giorgio
  • Checkelsky Joseph G
  • Georges Antoine
  • Comin Riccardo
  Proceedings of the National Academy of Sciences of the United States of America, National Academy of Sciences, 2025, 122 (45), pp.1-9. Electronic flat bands associated with quenched kinetic energy and heavy electron mass have attracted great interest for promoting strong electronic correlations and emergent phenomena such as high-temperature charge fractionalization and superconductivity. Intense experimental and theoretical research has been devoted to establishing the rich non-trivial metallic and heavy fermion phases intertwined with such localized electronic states. Here, we investigate the transition metal oxide spinel LiV2O4, an enigmatic heavy fermion compound lacking localized f orbital states. We use angle-resolved photoemission spectroscopy and dynamical mean field theory to reveal a new kind of correlation-induced flat band with suppressed inter-atomic electron hopping arising from intra-atomic Hund coupling. The appearance of heavy quasiparticles is ascribed to a proximate orbital-selective Mott state characterized by fluctuating local moments as evidenced by complementary magnetotransport measurements. The spectroscopic fingerprints of long-lived quasiparticles and their disappearance with increasing temperature further support the emergence of a high-temperature bad metal state observed in transport data. This work resolves a long-standing puzzle on the origin of heavy fermion behavior and unconventional transport in LiV2O4. Simultaneously, it opens a new path to achieving flat bands through electronic interactions in d-orbital systems with geometrical frustration, potentially enabling the realization of exotic phases of matter such as the fractionalized Fermi liquids. (10.1073/pnas.2518213122)
  DOI : 10.1073/pnas.2518213122
• Testing strong-field QED with the avalanche precursor
  
  • Mironov A.A
  • Bulanov S.S
  • Di Piazza A
  • Grech M
  • Lancia L
  • Meuren S
  • Palastro J
  • Riconda C
  • Rinderknecht H.G
  • Tzeferacos P
  • Gregori G
  Phys.Plasmas, 2025, 32 (9), pp.093302. A two-beam high-power laser facility is essential for the study of one of the most captivating phenomena predicted by strong-field quantum electrodynamics (QED) and yet unobserved experimentally: the avalanche-type cascade. In such a cascade, the energy of intense laser light can be efficiently transformed into high-energy radiation and electron-positron pairs. The future 50-petawatt-scale laser facility NSF OPAL will provide unique opportunities for studying such strong-field QED effects, as it is designed to deliver two ultra-intense, tightly focused laser pulses onto the interaction point. In this work, we investigate the potential of such a facility for studying elementary particle and plasma dynamics deeply in the quantum radiation-dominated regime, and the generation of QED avalanches. With 3D particle-in-cell simulations, we demonstrate that QED avalanche precursors can be reliably triggered under realistic laser parameters and layout (namely, focusing $f/2$, tilted optical axes, and non-ideal co-pointing) with the anticipated capabilities of NSF OPAL. We demonstrate that seed electrons can be efficiently injected into the laser focus by using targets of three types: a gas of heavy atoms, an overcritical plasma, and a thin foil. A strong positron and high-energy photon signal is generated in all cases. The cascade properties can be identified from the final particle distributions, which have a clear directional pattern. At increasing laser field intensity, such distributions provide signatures of the transition, first, to the radiation-dominated interaction regime, and then to a QED avalanche. Our findings can also be used for designing related future experiments. (10.1063/5.0283438)
  DOI : 10.1063/5.0283438
• Ionospheric Conductances at the Giant Planets of the Solar System: A Comparative Study of Ionization Sources and the Impact of Meteoric Ions
  
  • Clément Noé
  • Nakamura Yuki
  • Blanc Michel
  • Wang Yuxian
  • Al Saati Sariah
  Journal of Geophysical Research Space Physics, American Geophysical Union/Wiley, 2025, 130 (1), pp.e2024JA033061. The dynamics of giant planet magnetospheres is controlled by a complex interplay between their fast rotation, their interaction with the solar wind, and their diverse internal plasma and momentum sources. In the ionosphere, the Hall and Pedersen conductances are two key parameters that regulate the intensity of currents coupling the magnetosphere and the ionosphere, and the rate of angular momentum transfer and power carried by these currents. We perform a comparative study of Hall and Pedersen conductivities and conductances in the four giant planets of our Solar System -Jupiter, Saturn, Uranus and Neptune. We use a generic ionospheric model (restraining the studied ions to H + 3 , CH + 5 , and meteoric ions) to study the dependence of conductances on the structure and composition of these planets' upper atmospheres and on the main ionization sources (photoionization, ionization by precipitating electrons, and meteoroid ablation). After checking that our model reproduces the conclusions of Nakamura et al. ( 2022), https://doi.org/10.1029/2022ja030312 at Jupiter, that is, the contribution of meteoric ions to the height-integrated conductances is non-negligible, we show that this contribution could also be non-negligible at Saturn, Uranus and Neptune, compared with ionization processes caused by precipitating electrons of energies lower than a few keV (typical energies on these planets). However, because of their weaker magnetic field, the conductive layer of these planets is higher than the layer where meteoric ions are mainly produced, limiting their role in magnetosphere-ionosphere coupling. (10.1029/2024ja033061)
  DOI : 10.1029/2024ja033061
• The Yukawa potential of a non-homogeneous sphere, with new limits on an ultralight boson
  
  • Fayet Pierre
  Physical Review D, American Physical Society, 2025, 112 (9), pp.095018. Extremely weak long-range forces may lead to apparent violations of the Equivalence Principle. The final MICROSCOPE result, leading at 95 % c.l. to $|δ| < 4.5 \times 10^{-15}$ or $6.5 \times 10^{-15}$ for a positive or negative Eötvös parameter $δ$, requires taking into account the spin of the mediator, and the sign of $Δ(Q/A_r)_{\rm{Ti-Pt}}$ ($Q$ denoting the new charge involved). A coupling to $B-L$ or $B$ should verify $|g_{B-L}|<1.1 \times 10^{-25}$ or $|g_{B}| < 8 \times 10^{-25}$, for a spin-1 mediator of mass $m < 10^{-14}$ eV$/c^2$, with slightly different limits of $1.3 \times 10^{-25}$ or $\,6.6 \times 10^{-25}$ in the spin-0 case. The limits increase with $m$, in a way which depends on the density distribution within the Earth. This involves an hyperbolic form factor, expressed through a bilateral Laplace transform as $Φ(x=mR)= \langle\,\sinh mr/mr \,\rangle$, related by analytic continuation to the Earth form factor $Φ(ix)= \langle \,\sin mr/mr \,\rangle $. It may be expressed as $Φ(x) = \frac{3}{x^2}\, (\cosh x - \frac{\sinh x}{x}) \times\, \barρ(x)/ρ_0\,$, where $\barρ(x)$ is an effective density, decreasing from the average $ρ_0$ at $m=0$ down to the density at the periphery. We give general integral or multishell expressions of $Φ(x)$, evaluating it, and $\barρ(x)$, in a simplified 5-shell model. $Φ(x)$ may be expanded as $\, \sum \frac{x^{2n}}{(2n+1)!} \frac{\langle \,r^{2n}\,\rangle}{R^{2n}} \simeq 1 + .0827\ x^2 + .00271 \ x^4 + 4.78 \times 10^{-5}\,x^6 + 5.26\times 10^{-7}\, x^8 +\ ... \ $, absolutely convergent for all $x$ and potentially useful up to $x\approx 5$. The coupling limits increase at large $x$ like $mR \ e^{mz/2}/\sqrt{1+mr}$ ($z=r-R$ being the satellite altitude), getting multiplied by $\simeq 1.9,\ 34$, or $1.2\times 10^9$, for $m = 10^{-13},\ 10^{-12}$ or $10^{-11}$ eV$/c^2$, respectively. (10.1103/17wc-xxjm)
  DOI : 10.1103/17wc-xxjm
• Topological p-wave Superconductors with Disorder and Interactions
  
  • del Pozo Frederick
  • Herviou Loïc
  • Dmytruk Olesia
  • Hur Karyn Le
  Physical Review B, American Physical Society, 2025, 111 (7), pp.075170. interacting and disordered topological phases of coupled Kitaev wires, which may support further realistic applications of Majorana fermions. We develop a variety of analytical, mathematical and numerical methods for one and two-coupled wires, associated with a topological marker accessible from real-space correlation functions on the wire(s). We verify the stability of the topological superconducting phase and quantify disorder effects close to the quantum phase transitions, e.g. through two-point correlation functions or using a renormalization group (RG) analysis of disorder. We show for the first time that the double critical Ising (DCI) phase -- a fractional Majorana liquid characterized by a pair of half central charges and topological numbers -- is stabilized by strong interactions against disorder which respects the inversion symmetry between the wires (ie. parity conservation on each wire). In the presence of an inter-wire hopping term, the DCI phase turns into a protected topological phase with a bulk gap. We study the localization physics developing along the critical line for weaker interactions. (10.1103/PhysRevB.111.075170)
  DOI : 10.1103/PhysRevB.111.075170
• Relativistic energy-momentum tensor distributions in a polarized nucleon
  
  • Won Ho-Yeon
  • Lorcé Cédric
  Physical Review D, American Physical Society, 2025, 111 (9), pp.094021. We study in detail the relativistic distributions of energy, longitudinal momentum, longitudinal energy flux, and longitudinal thrust inside nucleons based on the quantum phase-space formalism. Similar to recent studies on the electromagnetic current, we include the effects of the nucleon polarization and show that the latter are essential for understanding how the Breit frame distributions transform under a longitudinal Lorentz boost. We also explicitly demonstrate that, in the infinite-momentum frame, these distributions allow one to recover not only the ``good'' but also the ``bad'' components of the light-front energy-momentum tensor distributions. (10.1103/PhysRevD.111.094021)
  DOI : 10.1103/PhysRevD.111.094021
• Using net quark number gain to probe the phases of QCD
  
  • Mari Surkau V. Tomas
  • Reinosa Urko
  Journal of Subatomic Particles and Cosmology, Elsevier, 2025, 4, pp.100227. We discuss an observable that probes the content of a QCD medium at finite temperature and chemical potential, the net quark number gain. It is the response of the thermal bath to a static quark or antiquark probe. While insignificant at high temperatures, it reveals the bath’s tendency to form meson-like or baryon-like configurations (depending on the probe and chemical potential) at low temperatures, which would screen the probe’s color charge. The net quark number gain also helps explain how a single quark/antiquark can be added to a supposedly confining medium in the first place: the latter provides the missing quarks/antiquarks to form hadron-like states. We sketch the derivation of this general result for temperatures much smaller than the constituent quark masses and discuss possible further applications to study the various features of the QCD phase diagram. (10.1016/j.jspc.2025.100227)
  DOI : 10.1016/j.jspc.2025.100227
• Constraining Glueball Couplings
  
  • Guerrieri Andrea L
  • Hebbar Aditya
  • van Rees Balt C
  Physical Review D, American Physical Society, 2025, 112 (9), pp.094023. We set up a numerical S-matrix bootstrap problem to rigorously constrain bound state couplings given by the residues of poles in elastic amplitudes. We extract upper bounds on these couplings that follow purely from unitarity, crossing symmetry, and the Roy equations within their proven domain of validity. First we consider amplitudes with a single spin 0 or spin 2 bound state, both with or without a self-coupling. Subsequently we investigate amplitudes with the spectrum of bound states corresponding to the estimated glueball masses of pure SU(3) Yang-Mills. In the latter case the 'glue-hedron', the space of allowed couplings, provides a first-principles constraint for future lattice estimates. (10.1103/f46t-xp36)
  DOI : 10.1103/f46t-xp36
• Quark confinement from an infrared safe approach
  
  • Peláez Marcela
  • Reinosa Urko
  • Serreau Julien
  • Tissier Matthieu
  • Wschebor Nicolás
  Physical Review D, American Physical Society, 2025, 112 (9), pp.094017. We revisit the nonabelian dipole problem in the context of a simple semiclassical approach which incorporates some essential features of the infrared sector of Yang-Mills theories in the Landau gauge, in particular, the fact that the running coupling remains of moderate size at infrared scales. We obtain a simple flux-tube solution in a controlled approximation scheme, that we compare to the results of lattice simulations. (10.1103/rk6n-t66l)
  DOI : 10.1103/rk6n-t66l
• Universality of the microcanonical entropy at large spin
  
  • Pal Sridip
  • Qiao Jiaxin
  • van Rees Balt C
  Communications in Mathematical Physics, Springer Verlag, 2025, 406 (12), pp.302. We consider rigorous consequences of modular invariance for two-dimensional unitary non-rational CFTs with $c > 1$. Simple estimates for the torus partition function can lead to remarkably strong results. We show in particular that the spectral density of spin-$J$ operators must grow like $\exp\left( \pi \sqrt{\frac{2}{3}(c-1) J} \right)/\sqrt{2J}$ in any twist interval at or above $(c-1)/12$, with a known twist-dependent prefactor. This proves that the large $J$ spectrum becomes dense even without averaging over spins. For twists below $(c-1)/12$ we establish that the growth must be strictly slower. Finally, we estimate how fast the maximal gap between two spin-$J$ operators must go to zero as $J$ becomes large. (10.1007/s00220-025-05442-y)
  DOI : 10.1007/s00220-025-05442-y
• The center-symmetric Landau gauge meets the lattice
  
  • van Egmond Duifje Maria
  • Oliveira Orlando
  • Reinosa Urko
  • Serreau Julien
  • Silva Paulo J
  • Tissier Matthieu
  Physical Review D, American Physical Society, 2025, 112 (1), pp.014512. A lattice implementation of the recently introduced center-symmetric Landau gauge is discussed and its predictions confronted with numerical Monte Carlo simulations. It is shown that the link average and the link correlators computed in that gauge are order parameters of the confinement-deconfinement transition at nonzero temperature. Strictly speaking, this requires a specific treatment of the Gribov copies that we discuss in detail. The numerical simulations comply with the theoretical predictions for the link average computed below and above the deconfinement temperature. Our results show that, within appropriately chosen gauges, one can construct local order parameters for center symmetry, as proxies for the non-local Polyakov loop. (10.1103/jcmj-jng4)
  DOI : 10.1103/jcmj-jng4
• Nucleon tensor form factors at large $N_{c}$
  
  • Ghim Nam-Yong
  • Won Ho-Yeon
  • Kim June-Young
  • Kim Hyun-Chul
  Physical Review D, American Physical Society, 2025, 111 (7), pp.074024. We investigate nucleon tensor form factors in the large-$N_{c}$ limit. In this picture, the nucleon emerges as a state of the $N_c$ valence quarks, which were bound by pion mean fields that were created by the presence of the valence quarks self-consistently. We find that the tensor charge ($g^{u-d}_{T}=0.99$) and the anomalous tensor magnetic moment ($\kappa^{u+d}_{T}=7.61$) are dominated by valence quarks, while the tensor quadrupole moment ($Q^{u-d}_{T}=-7.02$) shows significant sea quark effects. We examine how these quantities vary as the average size of the pion mean field is changed, showing interpolation between non-relativistic quark and Skyrme limits. We also observe that $g^{u-d}_{T}$ and $\kappa^{u+d}_{T}$ depend weakly on the pion mass. In contrast, $Q^{u-d}_{T}$ exhibits strong enhancement near the chiral limit. The numerical results are in good agreement with available lattice QCD data and provide predictions for unmeasured quantities. (10.1103/PhysRevD.111.074024)
  DOI : 10.1103/PhysRevD.111.074024
• Mott Transition and Volume Law Entanglement with Neural Quantum States
  
  • Gauvin-Ndiaye Chloé
  • Tindall Joseph
  • Moreno Javier Robledo
  • Georges Antoine
  Physical Review Letters, American Physical Society, 2025, 134 (7), pp.076502. The interplay between delocalisation and repulsive interactions can cause electronic systems to undergo a Mott transition between a metal and an insulator. Here we use neural network hidden fermion determinantal states (HFDS) to uncover this transition in the disordered, fully-connected Hubbard model. Whilst dynamical mean-field theory (DMFT) provides exact solutions to physical observables of the model in the thermodynamic limit, our method allows us to directly access the wavefunction for finite system sizes well beyond the reach of exact diagonalisation. We directly benchmark our results against state-of-the-art calculations obtained using a Matrix Product State (MPS) ansatz. We demonstrate how HFDS is able to obtain more accurate results in the metallic regime and in the vicinity of the transition, with the volume law of entanglement exhibited by the system being prohibitive to the MPS ansatz. We use the HFDS method to calculate the amplitudes of the wavefunction, the energy and double occupancy, the quasi-particle weight and the energy gap, hence providing novel insights into this model and the nature of the transition. Our work paves the way for the study of strongly correlated electron systems with neural quantum states. (10.1103/PhysRevLett.134.076502)
  DOI : 10.1103/PhysRevLett.134.076502
• Spin-orbit correlation and spatial distributions for spin-0 hadrons
  
  • Lorcé Cédric
  • Song Qin-Tao
  Physics Letters B, Elsevier, 2025, 864, pp.139433. The spin-orbit correlation in spin-0 hadrons can be investigated through the kinetic energy-momentum tensor form factor $\tilde F^q(t)$. We observe that the latter is also related to a torque about the radial direction, which we interpret as a chiral stress. If we neglect the quark mass contribution, then $\tilde F^q(t)$ is simply proportional to the electromagnetic form factor for spin-0 hadrons, and the spin-orbit correlation is equal to minus half of the valence quark number. Given the extensive studies on the electromagnetic form factor for spin-0 hadrons such as pions, kaons, and the $\alpha$ particle, we present the spatial distributions of chiral stress and kinetic spin-orbit correlation based on current parametrizations of the pion electromagnetic form factor. (10.1016/j.physletb.2025.139433)
  DOI : 10.1016/j.physletb.2025.139433
• Probing gluonic saturation in deeply virtual meson production beyond leading power
  
  • Boussarie Renaud
  • Fucilla Michael
  • Szymanowski Lech
  • Wallon Samuel
  Physical Review Letters, American Physical Society, 2025, 134 (4), pp.041901. Exclusive diffractive meson production represents a golden channel for investigating gluonic saturation inside nucleons and nuclei. In this letter, we settle a systematic framework to deal with beyond leading power corrections at small-$x$, including the saturation regime, and obtain the $\gamma^{*} \rightarrow M (\rho, \phi, \omega)$ impact factor with both incoming photon and outgoing meson carrying arbitrary polarizations. This is of particular interest since the saturation scale at modern colliders, although entering a perturbative regime, is not large enough to prevents higher-twist effects to be sizable. (10.1103/PhysRevLett.134.041901)
  DOI : 10.1103/PhysRevLett.134.041901
• Topological Matter and Fractional Entangled Geometry
  
  • Le Hur Karyn
  Phys.Rept., 2025, 1104, pp.1-42. Here, we review our progress on a geometrical approach of quantum physics and topological crystals starting from nature, electrodynamics of planets and linking with Dirac magnetic monopoles and gauge fields. The Bloch sphere of a quantum spin-$\frac{1}{2}$ particle can also acquire an integer topological charge in the presence of a radial magnetic field. We show that the global topological properties are revealed from the poles of the surface allowing a correspondence between smooth fields, metric and quantum distance. The information is transported from each pole to the equatorial plane on a thin Dirac string. We develop the theory, "the quantum topometry" in space and time, and present applications on transport from a Newtonian approach, on a quantized photo-electric effect from circular dichroism of light towards topological band structures of crystals. The occurrence of robust edge modes related to the topological lattice models are revealed analytically when deforming the sphere or ellipse onto a cylinder. The topological properties of the quantum Hall effect, the quantum anomalous Hall effect and the quantum spin Hall effect on the honeycomb lattice can be measured locally in the Brillouin zone from the light-matter coupling. The formalism allows us to include interaction effects from the momentum space. Interactions may also result in fractional entangled geometry within the curved space. We develop a relation between entangled wavefunction in quantum mechanics, coherent superposition of geometries, a way to one-half topological numbers and Majorana fermions. We show realizations in topological matter. We present a relation between axion electrodynamics, topological insulators on a surface of a cube and the two-spheres' model via the meron.
• Theorems for the Lightcone Bootstrap
  
  • van Rees Balt C
  SciPost Physics, SciPost Foundation, 2025, 18 (6), pp.207. Consider a conformally covariant four-point function of identical scalar operators with a discrete spectrum, a twist gap, and compatible with the unitarity conditions. We give a mathematical proof confirming that the spectrum and OPE coefficients at large spin and fixed twist always become that of a generalized free field theory. (10.21468/SciPostPhys.18.6.207)
  DOI : 10.21468/SciPostPhys.18.6.207
• Can outcome communication explain Bell nonlocality?
  
  • Vieira Carlos
  • de Gois Carlos
  • Lauand Pedro
  • Antunes Porto Lucas Emanuel
  • Designolle Sébastien
  • Quintino Marco Túlio
  , 2025. A central aspect of quantum information is that correlations between spacelike separated observers sharing entangled states cannot be reproduced by local hidden variable (LHV) models, a phenomenon known as Bell nonlocality. If one wishes to explain such correlations by classical means, a natural possibility is to allow communication between the parties. In particular, LHV models augmented with two bits of classical communication can explain the correlations of any two-qubit state. Would this still hold if communication is restricted to measurement outcomes? While in certain scenarios with a finite number of inputs the answer is yes, we prove that if a model must reproduce all projective measurements, then for any qubit-qudit state the answer is no. In fact, a qubit-qudit under projective measurements admits an LHV model with outcome communication if and only if it already admits an LHV model without communication. On the other hand, we also show that when restricted sets of measurements are considered (for instance, when the qubit measurements are in the upper hemisphere of the Bloch ball), outcome communication does offer an advantage. This exemplifies that trivial properties in standard LHV scenarios, such as deterministic measurements and outcome-relabelling, play a crucial role in the outcome communication scenario. (10.48550/arXiv.2510.12886)
  DOI : 10.48550/arXiv.2510.12886
• Enhanced Strange Metallicity due to Hubbard-<math display="inline"><mi>U</mi></math> Coulomb Repulsion
  
  • Hardy Andrew
  • Parcollet Olivier
  • Georges Antoine
  • Patel Aavishkar A
  Physical Review Letters, American Physical Society, 2025, 134 (3), pp.036502. We solve a model of electrons with Hubbard-<math display="inline"><mrow><mi>U</mi></mrow></math> Coulomb repulsion and a random Yukawa coupling to a two-dimensional bosonic bath, using an extended dynamical mean field theory scheme. Our model exhibits a quantum critical point, at which the repulsive component of the electron interactions strongly enhances the effects of the quantum critical bosonic fluctuations on the electrons, leading to a breakdown of Fermi liquid physics and the formation of a strange metal with “Planckian” [<math display="inline"><mrow><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><msub><mrow><mi>k</mi></mrow><mrow><mi>B</mi></mrow></msub><mi>T</mi><mo>/</mo><mi>ℏ</mi><mo stretchy="false">)</mo></mrow></math>] quasiparticle decay rates at low temperatures <math display="inline"><mi>T</mi><mo stretchy="false">→</mo><mn>0</mn></math>. Furthermore, the eventual Mott transition that occurs as the repulsion is increased seemingly bounds the maximum decay rate in the strange metal. Our results provide insight into low-temperature strange metallicity observed in proximity to a Mott transition, as is observed, for instance, in recent experiments on certain moiré materials. (10.1103/PhysRevLett.134.036502)
  DOI : 10.1103/PhysRevLett.134.036502
• Interacting topological quantum aspects with light and geometrical functions
  
  • Le Hur Karyn
  Phys.Rept., 2025, 1104, pp.1-42. I review my recent progress and develop a geometrical approach in the quantum with light as a guide, from the vector potential in classical physics, revealing that topological properties can be equivalently measured from the poles of a sphere. The topological state is induced on the Bloch sphere of a spin-1/2 particle from a radial magnetic field related to the physics of Skyrmions. This shows a relation between the global topological response being measured at the poles, the response to a circularly polarized field and the quantum metric. I show how this approach is helpful for the classification of matter with the detection of the global topological invariant at specific points in the Brillouin zone, e.g. the Dirac points, from the responses to electromagnetic waves such as circularly polarized light and from new geometrical functions associated to the quantum metric measuring the quantum Hall and spin Hall conductivities. The <math display="inline" id="d1e807" altimg="si392.svg"><mi>M</mi></math> point associated to the Brillouin zone of the honeycomb lattice also reveals the topological signature. Interactions are included in momentum space within a stochastic variational approach. In a realistic quantum model of interacting spins, this leads to fractional topological entangled aspects with a correspondence between a pair of half invariants and a Einstein–Podolsky–Rosen (EPR) pair or Bell state at one pole. I also formulate a correspondence between fractional topological numbers and resonating valence bond states. This approach gives further insight on the characterization of topological matter linked to superconductivity, protected topological semimetals in two dimensions and on the search of Majorana fermions for topologically protected quantum information. We also address a correspondence with the fractional quantum Hall effect and surface states of three-dimensional topological insulators. (10.1016/j.physrep.2024.11.003)
  DOI : 10.1016/j.physrep.2024.11.003