Publications

Order by: publication date number of citations

• Optimal mass variables for semivisible jets

  Kevin Pedro, Prasanth Shyamsundar

  SciPost Phys. Core 6, 067 (2023) · published 17 October 2023 | Toggle abstract · pdf

  Strongly coupled hidden sector theories predict collider production of invisible, composite dark matter candidates mixed with standard model hadrons in the form of semivisible jets. Classical mass reconstruction techniques may not be optimal for these unusual topologies, in which the missing transverse momentum comes from massive particles and has a nontrivial relationship to the visible jet momentum. We apply the artificial event variable network, a semisupervised, interpretable machine learning technique that uses an information bottleneck, to derive superior mass reconstruction functions for several cases of resonant semivisible jet production. We demonstrate that the technique can extrapolate to unknown signal model parameter values. We further demonstrate the viability of conducting an actual search for new physics using this method, by applying the learned functions to standard model background events from quantum chromodynamics.

  4 citations

• Chaos in the vicinity of a singularity in the three-body problem: The equilateral triangle experiment in the zero angular momentum limit

  Hugo D. Parischewsky, Alessandro A. Trani, Nathan W. C. Leigh

  SciPost Phys. Core 6, 016 (2023) · published 21 March 2023 | Toggle abstract · pdf

  We present numerical simulations of the gravitational three-body problem, in which three particles lie at rest close to the vertices of an equilateral triangle. In the unperturbed problem, the three particles fall towards the center of mass of the system to form a three-body collision, or singularity, where the particles overlap in space and time. By perturbing the initial positions of the particles, we are able to study chaos in the vicinity of the singularity. Here we cover both the singular region close to the unperturbed configuration and the binary-single scattering regime where one side of the triangle is very short compared to the other two. We make phase space plots to study the regular and ergodic subsets of our simulations and compare them with the outcomes expected from the statistical escape theory of the three-body problem. We further provide fits to the ergodic subset to characterize the properties of the left-over binaries. We identify the discrepancy between the statistical theory and the simulations in the regular subset of interactions, which only exhibits weak chaos. As we decrease the scale of the perturbations in the initial positions, the phase space becomes entirely dominated by regular interactions, according to our metric for chaos. Finally, we show the effect of general relativity corrections by simulating the same scenario with the inclusion of post-Newtonian corrections to the equations of motion.

  4 citations

• Underground laboratories

  Aldo Ianni

  SciPost Phys. Proc. 12, 007 (2023) · published 3 July 2023 | Toggle abstract · pdf

  A brief review on underground laboratories at the time of IDM 2022 is reported. General characteristics of these research infrastructures are discussed and a few highlights from different laboratories are reported. The idea of networking between underground laboratories is discussed.

  4 citations

• Boundary description of microstates of the two-dimensional black hole

  Amr Ahmadain, Alexander Frenkel, Krishnendu Ray, Ronak M. Soni

  SciPost Phys. 16, 020 (2024) · published 22 January 2024 | Toggle abstract · pdf

  We identify the microstates of the non-supersymmetric, asymptotically flat 2d black hole in the dual c=1 matrix quantum mechanics (MQM). We calculate the partition function of the theory using Hamiltonian methods and reproduce one of two conflicting results found by Kazakov and Tseytlin. We find the entropy by counting states and the energy by approximately solving the Schrödinger equation. The dominant contribution to the partition function in the double-scaling limit is a novel bound state that can be considered an explicit dual of the black hole microstates. This bound state is long-lived and evaporates slowly, exactly like a black hole in asymptotically flat space.

  4 citations

• Dipole symmetries from the topology of the phase space and the constraints on the low-energy spectrum

  Tomáš Brauner, Naoki Yamamoto, Ryo Yokokura

  SciPost Phys. 16, 051 (2024) · published 20 February 2024 | Toggle abstract · pdf

  We demonstrate the general existence of a local dipole conservation law in bosonic field theory. The scalar charge density arises from the symplectic form of the system, whereas the tensor current descends from its stress tensor. The algebra of spatial translations becomes centrally extended in presence of field configurations with a finite nonzero charge. Furthermore, when the symplectic form is closed but not exact, the system may, surprisingly, lack a well-defined momentum density. This leads to a theorem for the presence of additional light modes in the system whenever the short-distance physics is governed by a translationally invariant local field theory. We also illustrate this mechanism for axion electrodynamics as an example of a system with Nambu-Goldstone modes of higher-form symmetries.

  4 citations

• Duality in quantum transport models

  Rouven Frassek, Cristian Giardinà, Jorge Kurchan

  SciPost Phys. 10, 135 (2021) · published 8 June 2021 | Toggle abstract · pdf

  We develop the 'duality approach', that has been extensively studied for classical models of transport, for quantum systems in contact with a thermal 'Lindbladian' bath. The method provides (a) a mapping of the original model to a simpler one, containing only a few particles and (b) shows that any dynamic process of this kind with generic baths may be mapped onto one with equilibrium baths. We exemplify this through the study of a particular model: the quantum symmetric exclusion process introduced in [D. Bernard, T. Jin, Phys. Rev. Lett. 123, 080601 (2019)]. As in the classical case, the whole construction becomes intelligible by considering the dynamical symmetries of the problem.

  4 citations

• Higher-genus Fay-like identities from meromorphic generating functions

  Konstantin Baune, Johannes Broedel, Egor Im, Artyom Lisitsyn, Yannis Moeckli

  SciPost Phys. 18, 093 (2025) · published 14 March 2025 | Toggle abstract · pdf

  A possible way of constructing polylogarithms on Riemann surfaces of higher genera facilitates integration kernels, which can be derived from generating functions incorporating the geometry of the surface. Functional relations among polylogarithms rely on identities for those integration kernels. In this article, we derive identities for Enriquez' meromorphic generating function and investigate the implications for the associated integration kernels. The resulting identities are shown to be exhaustive and therefore reproduce all identities for Enriquez' kernels conjectured in arXiv:2407.11476 recently.

  4 citations

• Two-parton scattering in the high-energy limit: climbing two- and three-Reggeon ladders

  G. Falcioni, E. Gardi, N. Maher, C. Milloy, L. Vernazza

  SciPost Phys. Proc. 7, 007 (2022) · published 20 June 2022 | Toggle abstract · pdf

  We review recent progress on the calculation of scattering amplitudes in the high-energy limit. We start by illustrating the shockwave formalism, which allows one to calculate amplitudes as iterated solutions of rapidity evolution equations. We then focus on our recent results regarding 2 -> 2 parton scattering. We present the calculation of the imaginary part of the amplitude, at next-to-leading logarithmic accuracy in the high-energy logarithms, formally to all orders, and in practice to 13 loops. We then discuss the computation of the real part of the amplitude at next-to-next-to-leading logarithmic accuracy and through four loops. Both computations are carried in full colour, and provide new insight into the analytic structure of scattering amplitudes and their infrared singularity structure.

  4 citations

• Conjectures about the structure of strong- and weak-coupling expansions of a few ground-state observables in the Lieb-Liniger and Yang-Gaudin models

  Guillaume Lang

  SciPost Phys. 7, 055 (2019) · published 23 October 2019 | Toggle abstract · pdf

  In this paper, we apply experimental number theory to two integrable quantum models in one dimension, the Lieb-Liniger Bose gas and the Yang-Gaudin Fermi gas with contact interactions. We identify patterns in weak- and strong-coupling series expansions of the ground-state energy, local correlation functions and pressure. Based on the most accurate data available in the literature, we make a few conjectures about their mathematical structure and extrapolate to higher orders.

  4 citations

• Matrix method and the suppression of Runge's phenomenon

  Shui-Fa Shen, Wei-Liang Qian, Jie Zhang, Yu Pan, Yu-Peng Yan, Cheng-Gang Shao

  SciPost Phys. Core 7, 034 (2024) · published 5 June 2024 | Toggle abstract · pdf

  Higher-degree polynomial interpolations carried out on uniformly distributed nodes are often plagued by overfitting, known as Runge's phenomenon. This work investigates Runge's phenomenon and its suppression in various versions of the matrix method for black hole quasinormal modes. It is shown that an appropriate choice of boundary conditions gives rise to desirable suppression of oscillations associated with the increasing Lebesgue constant. For the case of discontinuous effective potentials, where the application of the above boundary condition is not feasible, the recently proposed scheme with delimited expansion domain also leads to satisfactory results. The onset of Runge's phenomenon and its effective suppression are demonstrated by evaluating the relevant waveforms. Furthermore, we argue that both scenarios are either closely related to or practical imitations of the Chebyshev grid. The implications of the present study are also addressed.

  4 citations