Publications

2025

• Exploring orbital angular momentum and spin-orbit correlation for gluons at the Electron-Ion Collider
  
  • Bhattacharya Shohini
  • Boussarie Renaud
  • Hatta Yoshitaka
  Physical Review D, American Physical Society, 2025, 111 (3), pp.034019. In our previous work [Phys. Rev. Lett. 128, 182002 (2022)], we introduced a pioneering observable aimed at experimentally detecting the orbital angular momentum (OAM) of gluons. Our focus was on the longitudinal double spin asymmetry observed in exclusive dijet production during electron-proton scattering. We demonstrated the sensitivity of the $\cos \phi$ angular correlation between the scattered electron and proton as a probe for gluon OAM at small-$x$ and its intricate interplay with gluon helicity. This current work provides a comprehensive exposition, diving further into the aforementioned calculation with added elaboration and in-depth analysis. We reveal that, in addition to the gluon OAM, one also gains access to the spin-orbit correlation of gluons. We supplement our work with a detailed numerical analysis of our observables for the kinematics of the Electron-Ion Collider. In addition to dijet production, we also consider the recently proposed semi-inclusive diffractive deep inelastic scattering process which potentially offers experimental advantages over dijet measurements. Finally, we investigate quark-channel contributions to these processes and find an unexpected breakdown of collinear factorization. (10.1103/PhysRevD.111.034019)
  DOI : 10.1103/PhysRevD.111.034019
• The infrared-safe Minkowskian Curci-Ferrari model
  
  • Oribe Santiago
  • Peláez Marcela
  • Reinosa Urko
  Physical Review D, American Physical Society, 2025, 112 (1), pp.014005. We discuss the existence of Landau-pole-free renormalization group trajectories in the Minkowskian version of the Curci-Ferrari model as a function of a running parameter $q^2$ associated to the four-vector $q$ at which renormalization conditions are imposed, and which can take both space-like ($\smash{q^2<0}$) and time-like ($\smash{q^2>0}$) values. We discuss two possible extensions of the infrared-safe scheme defined in Ref. [Phys. Rev. D, 84, 045018, 2011] for the Euclidean version of the model, which coincide with the latter in the space-like region upon identifying $\smash{Q^2\equiv-q^2}$ with the square of the renormalization scale in that reference. The first extension uses real-valued renormalization factors and leads to a flow in the time-like region with a similar structure as the flow in the space-like region (or in the Euclidean model), including a non-trivial fixed point and a family of trajectories bounded at all scales by the value of the coupling at this fixed point. Interestingly, the fixed point in the time-like region has a much smaller value of $\lambda\equiv g^2N/16\pi^2$ than the corresponding one in the space-like region, a value closer to the perturbative boundary $\smash{\lambda=1}$. However, in this real-valued infrared-safe scheme, the flow cannot connect the time-like and space-like regions. Thus, it is not possible to deduce the relevant time-like flow trajectory from the sole knowledge of a space-like flow trajectory. To try to cure this problem, we investigate a second extension of the Euclidean IR-safe scheme, which allows for complex-valued renormalization factors. We discuss under which conditions these schemes can make sense and study their ability to connect space- and time-like flow trajectories. In particular, we investigate to which types of time-like trajectories the perturbative space-like trajectories are mapped onto. (10.1103/gxg3-5vxr)
  DOI : 10.1103/gxg3-5vxr
• Triviality proof for mean-field $\varphi_4^4$-theories
  
  • Wang Pierre
  • Kopper Christoph
  Journal of Mathematical Physics, American Institute of Physics (AIP), 2025, 66 (6), pp.062302. The differential equations of the Wilson renormalization group are a powerful tool to study the Schwinger functions of Euclidean quantum field theory. In particular renormalization theory can be based entirely on inductively bounding their perturbatively expanded solutions. Recently the solutions of these equations for scalar field theory have been analysed rigorously without recourse to perturbation theory, at the cost of restricting to the mean-field approximation. In particular it was shown there that one-component $\varphi^4_4$-theory is trivial if the bare coupling constant of the UV regularized theory is not large. This paper presents progress w.r.t. Kopper's previous paper on asymptotically free solutions of the mean-field scalar flow equations: 1. The upper bound on the bare coupling is sent to infinity and the proof is extended to $O(N)$ vector models. 2. The unphysical infrared cutoff used for technical simplicity is replaced by a physical mass. (10.1063/5.0231068)
  DOI : 10.1063/5.0231068
• Twist corrections to exclusive vector meson production in a saturation framework
  
  • Boussarie Renaud
  • Fucilla Michael
  • Szymanowski Lech
  • Wallon Samuel
  Physical Review D, American Physical Society, 2025, 111 (1), pp.014032. We develop a framework combining the higher-twist formalism of exclusive processes in the $s$ channel with the semi-classical effective description of small-$x$ physics in the $t$ channel. We apply it to transversely polarized light vector meson production, $\gamma^{*} p \rightarrow V (\rho, \varphi ,\omega) \; p$, which starts at the next-to-leading power and for which a purely collinear treatment leads to end-point singularities. The result is obtained in the most general kinematics, including both forward and non-forward cases by preserving the full impact parameter dependence in the non-perturbative correlators, in both momentum and coordinate space representations. A systematic expansion of the Wilson lines in terms of Reggeized gluon fields is performed in order to obtain the results in the weak-field BFKL approximation. These new results will allow for investigating the dilute-to-dense regime transition of QCD for a wide class of observables. (10.1103/PhysRevD.111.014032)
  DOI : 10.1103/PhysRevD.111.014032
• Berry Phases in the Bosonization of Nonlinear Edge Modes
  
  • Beauvillain Mathieu
  • Oblak Blagoje
  • Petropoulos Marios P.
  Physical Review B, American Physical Society, 2025, 112 (12), pp.125136. We consider chiral, generally nonlinear density waves in one dimension, modelling the bosonized edge modes of a two-dimensional fermionic topological insulator. Using the coincidence between bosonization and Lie-Poisson dynamics on an affine U(1) group, we show that wave profiles which are periodic in time produce Berry phases accumulated by the underlying fermionic field. These phases can be evaluated in closed form for any Hamiltonian, and they serve as a diagnostic of nonlinearity. As an explicit example, we discuss the Korteweg-de Vries equation, viewed as a model of nonlinear quantum Hall edge modes. (10.1103/68f9-3td6)
  DOI : 10.1103/68f9-3td6
• Pressure inside hadrons: criticism, conjectures, and all that
  
  • Lorcé Cédric
  • Schweitzer Peter
  Acta Physica Polonica B, Jagellonian University, Cracow, 2025, 56 (3), pp.3-A17. The interpretation of the energy-momentum tensor form factor $D(t)$ of hadrons in terms of pressure and shear force distributions is discussed, concerns raised in the literature are reviewed, and ways to reconcile the concerns with the interpretation are indicated. (10.5506/aphyspolb.56.3-a17)
  DOI : 10.5506/aphyspolb.56.3-a17
• Higher derivative couplings with multi-tensor multiplets in 6D supergravity, action and anomalies
  
  • Bossard Guillaume
  • Kleinschmidt Axel
  • Sezgin Ergin
  Journal of High Energy Physics, Springer, 2025, 03, pp.108. We revisit six-dimensional (1,0) supergravity coupled to nT tensor multiplets and Yang-Mills fields for nT>1 for which no covariant action exists. We construct the action in the Henneaux-Teitelboim approach and in the presence of a gauge anomaly. We moreover obtain the supersymmetric Green-Schwarz counterterm for the gravitational anomaly for arbitrary matter content. (10.1007/JHEP03(2025)108)
  DOI : 10.1007/JHEP03(2025)108
• Causal and Stable Superfluid Hydrodynamics
  
  • Hoult Raphael E
  • Shukla Ashish
  Journal of High Energy Physics, Springer, 2025, 04, pp.172. We investigate the linearized stability and causality properties of relativistic viscous superfluid hydrodynamics. The Landau-Lifshitz-Clark-Putterman formulation for the theory of relativistic viscous superfluids suffers from the same instability and acausality issues as the relativistic Navier-Stokes equation for normal fluids when written in the formulations of Eckart or Landau and Lifshitz. We show that conditions to ensure stability and causality can be satisfied with judicious redefinitions of the hydrodynamic variables. The conditions we obtain hold at non-zero superfluid velocity as well. (10.1007/JHEP04(2025)172)
  DOI : 10.1007/JHEP04(2025)172
• Entropy, purity and gluon cascades at high energies with recombinations and transitions to vacuum
  
  • Kutak Krzysztof
  • Praszałowicz Michał
  European Physical Journal C: Particles and Fields, Springer Verlag (Germany), 2025, 85 (10), pp.1215. We study one dimensional dipole cascade models in the high-energy limit of QCD. Motivated by data on hadron multiplicities in the LHCb kinematical range, we generalize existing cascade models for splitting and recombination to account also for transitions to the vacuum. This modification allows us to describe the data. Furthermore, we perform both analytical and numerical studies of the cascades and find that the cascade including loop corrections, as well as the one accounting for transitions to the vacuum, can both be related to the Negative Binomial Distribution. In the latter case, however, one must properly normalize the cascade to account for transitions to the vacuum. We also study the scaling properties of the cascades and identify new regimes, which we call "focal" and "parallel." Finally, we investigate the Quantum Information (QI) measures of the cascades, which allow us to highlight their distinctive properties. (10.1140/epjc/s10052-025-14981-6)
  DOI : 10.1140/epjc/s10052-025-14981-6
• 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
• 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
• 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
• 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
• 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