Publications

Order by: publication date number of citations

• BFKL phenomenology: resummation of high-energy logs in inclusive processes

  Francesco Giovanni Celiberto, Michael Fucilla, Dmitry Yu. Ivanov, Mohammed M. A. Mohammed, Alessandro Papa

  SciPost Phys. Proc. 10, 002 (2022) · published 10 August 2022 | Toggle abstract · pdf

  We present recent phenomenological studies, tailored on kinematic configurations typical of current and forthcoming analyses at the LHC, for two novel probe channels of the BFKL resummation of energy logarithms. Particular attention is drawn to the behavior of distributions differential in azimuthal angle and rapidity, where significant high-energy effects are expected.

  5 citations

• Accelerating equilibrium spin-glass simulations using quantum annealers via generative deep learning

  Giuseppe Scriva, Emanuele Costa, Benjamin McNaughton, Sebastiano Pilati

  SciPost Phys. 15, 018 (2023) · published 20 July 2023 | Toggle abstract · pdf

  Adiabatic quantum computers, such as the quantum annealers commercialized by D-Wave Systems Inc., are routinely used to tackle combinatorial optimization problems. In this article, we show how to exploit them to accelerate equilibrium Markov chain Monte Carlo simulations of computationally challenging spin-glass models at low but finite temperatures. This is achieved by training generative neural networks on data produced by a D-Wave quantum annealer, and then using them to generate smart proposals for the Metropolis-Hastings algorithm. In particular, we explore hybrid schemes by combining single spin-flip and neural proposals, as well as D-Wave and classical Monte Carlo training data. The hybrid algorithm outperforms the single spin-flip Metropolis-Hastings algorithm. It is competitive with parallel tempering in terms of correlation times, with the significant benefit of a much shorter equilibration time.

  5 citations

• Nonlinear Luttinger liquid: Exact result for the Green function in terms of the fourth Painlevé transcendent

  Tom Price, Dmitry L. Kovrizhin, Austen Lamacraft

  SciPost Phys. 2, 005 (2017) · published 21 February 2017 | Toggle abstract · pdf

  We show that exact time dependent single particle Green function in the Imambekov-Glazman theory of nonlinear Luttinger liquids can be written, for any value of the Luttinger parameter, in terms of a particular solution of the Painlev\'e IV equation. Our expression for the Green function has a form analogous to the celebrated Tracy-Widom result connecting the Airy kernel with Painlev\'e II. The asymptotic power law of the exact solution as a function of a single scaling variable $x/\sqrt{t}$ agrees with the mobile impurity results. The full shape of the Green function in the thermodynamic limit is recovered with arbitrary precision via a simple numerical integration of a nonlinear ODE.

  5 citations

• A splash in a one-dimensional cold gas

  Subhadip Chakraborti, Abhishek Dhar, P. L. Krapivsky

  SciPost Phys. 13, 074 (2022) · published 29 September 2022 | Toggle abstract · pdf

  We consider a set of hard point particles distributed uniformly with a specified density on the positive half-line and all initially at rest. The particle masses alternate between two values, $m$ and $M$. The particles interact via collisions that conserve energy and momentum. We study the cascade of activity that results when the left-most particle is given a positive velocity. At long times we find that this leads to two fascinating features in the observed dynamics. First, in the bulk of the gas, a shock front develops separating the cold gas from a thermalized region. The shock-front travels sub-ballistically, with the bulk described by self-similar solutions of Euler hydrodynamics. Second, there is a splash region formed by the recoiled particles which move ballistically with negative velocities. The splash region is completely non-hydrodynamic and we propose two conjectures for the long time particle dynamics in this region. We provide a detailed analytic understanding of these coexisting regimes. These are supported by the results of molecular dynamics simulations.

  5 citations

• Beyond Fermi's golden rule with the statistical Jacobi approximation

  David M. Long, Dominik Hahn, Marin Bukov, Anushya Chandran

  SciPost Phys. 15, 251 (2023) · published 22 December 2023 | Toggle abstract · pdf

  Many problems in quantum dynamics can be cast as the decay of a single quantum state into a continuum. The time-dependent overlap with the initial state, called the fidelity, characterizes this decay. We derive an analytic expression for the fidelity after a quench to an ergodic Hamiltonian. The expression is valid for both weak and strong quenches, and timescales before finiteness of the Hilbert space limits the fidelity. It reproduces initial quadratic decay and asymptotic exponential decay with a rate which, for strong quenches, differs from Fermi's golden rule. The analysis relies on the statistical Jacobi approximation (SJA), which was originally applied in nearly localized systems, and which we here adapt to well-thermalizing systems. Our results demonstrate that the SJA is predictive in disparate regimes of quantum dynamics.

  5 citations

• Hybrid high-energy/collinear factorization in a heavy-light dijets system reaction

  Andrèe Dafne Bolognino, Francesco Giovanni Celiberto, Michael Fucilla, Dmitry Yu. Ivanov, Alessandro Papa

  SciPost Phys. Proc. 8, 068 (2022) · published 12 July 2022 | Toggle abstract · pdf

  We propose the inclusive hadroproduction of a heavy-light dijet system, as a new channel for the investigation of high energy QCD. We build up a hybrid factorization that incorporates a partial next-to-leading BFKL resummation inside the standard collinear description of observables. We present a detailed analysis of different observables: cross-section summed over azimuthal angles and differential in rapidity and azimuthal distribution. The stability that these distributions show under higher-order corrections motivates our interest in future studies, doable at new generation colliding machines.

  5 citations

• Magnetic properties of the putative higher-order topological insulator EuIn$_2$As$_2$

  Tomasz Toliński, Dariusz Kaczorowski

  SciPost Phys. Proc. 11, 005 (2023) · published 5 June 2023 | Toggle abstract · pdf

  In higher-order topological insulator (HOTI), a gap is preserved both for the bulk and the surface states, and only hinges or corners become gapless. Recently, it has been predicted that the antiferromagnetic compound EuIn$_2$As$_2$ can host both the HOTI and axion insulator features. Preliminary experimental confirmation of this finding was obtained using angle-resolved photoemission spectroscopy. The main objective of this work was to characterize the anisotropic magnetic properties of single-crystalline EuIn$_2$As$_2$. In addition, complementary studies on the transport properties, heat capacity, and magnetocaloric effect in this compound were performed.

  5 citations

• Optimal, fast, and robust inference of reionization-era cosmology with the 21cmPIE-INN

  Benedikt Schosser, Caroline Heneka, Tilman Plehn

  SciPost Phys. Core 8, 037 (2025) · published 10 April 2025 | Toggle abstract · pdf

  Modern machine learning will allow for simulation-based inference from reionization-era 21cm observations at the Square Kilometre Array. Our framework combines a convolutional summary network and a conditional invertible network through a physics-inspired latent representation. It allows for an efficient and extremely fast determination of the posteriors of astrophysical and cosmological parameters, jointly with well-calibrated and on average unbiased summaries. The sensitivity to non-Gaussian information makes our method a promising alternative to the established power spectra.

  5 citations

• kdotpy: k·p theory on a lattice for simulating semiconductor band structures

  Wouter Beugeling, Florian Bayer, Christian Berger, Jan Böttcher, Leonid Bovkun, Christopher Fuchs, Maximilian Hofer, Saquib Shamim, Moritz Siebert, Li-Xian Wang, Ewelina M. Hankiewicz, Tobias Kießling, Hartmut Buhmann, Laurens W. Molenkamp

  SciPost Phys. Codebases 47 (2025) · published 28 January 2025 | Toggle abstract · pdf

  The software project kdotpy provides a Python application for simulating electronic band structures of semiconductor devices with k·p theory on a lattice. The application implements the widely used Kane model, capable of reliable predictions of transport and optical properties for a large variety of topological and non-topological materials with a zincblende crystal structure. The application automates the tedious steps of simulating band structures. The user inputs the relevant physical parameters on the command line, for example materials and dimensions of the device, magnetic field, and temperature. The program constructs the appropriate matrix Hamiltonian on a discretized lattice of spatial coordinates and diagonalizes it. The physical observables are extracted from the eigenvalues and eigenvectors and saved as output. The program is highly customizable with a large set of configuration options and material parameters.

  5 citations

• The MSHT20 Parton Distribution Functions

  R.S. Thorne, S. Bailey, T. Cridge, L. Harland-Lang, A.D. Martin

  SciPost Phys. Proc. 8, 018 (2022) · published 11 July 2022 | Toggle abstract · pdf

  We present the new MSHT20 set of parton distribution functions (PDFs) of the proton, determined from a global analysis of the available hard scattering data and superseding the MMHT14 sets. The parameterisation is now adapted and extended and we include a large number of new data sets: the final HERA and Tevatron data, and a significant number of LHC data sets on vector boson production, inclusive jets and top quark distributions. We include up to NNLO QCD corrections for all data sets that play a major role in the fit. There are some changes to central PDF values and a significant reduction in the uncertainties, but the PDFs and the predictions using them are generally within one standard deviation of the MMHT14 results. We discuss the phenomenological impact of our results.

  5 citations