Blar i Vitenskapelige publikasjoner (IMF) på emneord "VDP::Matematikk og Naturvitenskap: 400::Fysikk: 430"

Viser treff 61-80 av 80

    • Stable solvers for real-time Complex Langevin 

      Alvestad, Daniel; Larsen, Rasmus Normann; Rothkopf, Alexander Karl (Peer reviewed; Journal article, 2021-08)
      This study explores the potential of modern implicit solvers for stochastic partial differential equations in the simulation of real-time complex Langevin dynamics. Not only do these methods offer asymptotic stability, ...

    • Statistics on Lefschetz thimbles: Bell/Leggett-Garg inequalities and the classical-statistical approximation 

      Tranberg, Anders; Millington, P; Mou, Zonggang; Saffin, Paul M. (Peer reviewed; Journal article, 2021)
      Inspired by Lefschetz thimble theory, we treat Quantum Field Theory as a statistical theory with a complex Probability Distribution Function (PDF). Such complex-valued PDFs permit the violation of Bell-type inequalities, ...

    • Stochastic gravitational wave background from stellar origin binary black holes in LISA 

      Babak, Stanislav; Caprini, Chiara; Figueroa, Daniel G.; Karnesis, Nikolaos; Marcoccia, Paolo; Nardini, Germano; Pieroni, Mauro; Ricciardone, Angelo; Sesana, Alberto; Torrado, Jesús (Peer reviewed; Journal article, 2023)
      We use the latest constraints on the population of stellar origin binary black holes (SOBBH) from LIGO/Virgo/KAGRA (LVK) observations, to estimate the stochastic gravitational wave background (SGWB) they generate in the ...

    • Stochastic inflation from quantum field theory and the parametric dependence of the effective noise amplitude 

      Andersen, Jens Oluf; Tranberg, Anders; Eriksson, Magdalena Britt (Peer reviewed; Journal article, 2022-02)
      The non-linear dynamics of long-wavelength cosmological fluctuations may be phrased in terms of an effective classical, but stochastic evolution equation. The stochastic noise represents short-wavelength modes that continually ...

    • Symmetry and Equivalence in Teleparallel Gravity 

      Coley, Alan; van den Hoogen, Robert; McNutt, David Duncan (Peer reviewed; Journal article, 2020-07)
      In theories such as teleparallel gravity and its extensions, the frame basis replaces the metric tensor as the primary object of study. A choice of coordinate system, frame basis, and spin-connection must be made to obtain ...

    • T3-invariant heterotic Hull-Strominger solutions 

      Svanes, Eirik Eik; Acharya, Bobby S.; Kinsella, Alex (Peer reviewed; Journal article, 2021-01)
      We consider the heterotic string on Calabi-Yau manifolds admitting a Strominger-Yau-Zaslow fibration. Upon reducing the system in the T3-directions, the Hermitian Yang-Mills conditions can then be reinterpreted as a complex ...

    • Thermalization and dynamical spectral properties in the quark-meson model 

      Shen, Lisa; Berges, Jürgen; Pawlowski, Jan M.; Rothkopf, Alexander Karl (Peer reviewed; Journal article, 2020-07)
      We investigate the nonequilibrium evolution of the quark-meson model using two-particle irreducible effective action techniques. Our numerical simulations, which include the full dynamics of the order parameter of chiral ...

    • Thermalization of weakly coupled non-Abelian plasmas at next-to-leading order 

      Fu, Yu; Ghiglieri, Jacopo; Iqbal, Shahin; Kurkela, Eero Aleksi (Peer reviewed; Journal article, 2023)
      We employ the QCD kinetic theory, including next-to-leading(NLO) order corrections in coupling constant, to study the evolution of weakly coupled non-Abelian plasmas towards thermal equilibrium. For two characteristic ...

    • Thermodynamics of antiferromagnetic solids in magnetic fields 

      Brauner, Tomas; Hofmann, Christoph (Peer reviewed; Journal article, 2020)
      We analyze the thermodynamic properties of antiferromagnetic solids subjected to a combination of mutually orthogonal uniform magnetic and staggered fields. Low- temperature series for the pressure, order parameter and ...

    • Thoughts about the utility of perturbative QCD in the cores of neutron stars – contribution to a roundtable discussion on neutron stars and QCD 

      Kurkela, Eero Aleksi (Peer reviewed; Journal article, 2022)
      In this contribution, I discuss the utility that perturbative QCD offers in studying the matter in the cores of neutron stars. I discuss the reasons why perturbative QCD can constrain the equation of state at densities far ...

    • Topological G2 and Spin(7) strings at 1-loop from double complexes 

      Ashmore, Anthony; Coimbra, André; Strickland-Constable, Charles; Svanes, Eirik Eik; Tennyson, David (Peer reviewed; Journal article, 2022)
      We study the topological G2 and Spin(7) strings at 1-loop. We define new double complexes for supersymmetric NSNS backgrounds of string theory using generalised geometry. The 1-loop partition function then has a target-space ...

    • Towards dielectric relaxation at a single molecule scale 

      Stetsovych, V; Feigl, Simon; Vranik, Radovan; Wit, Barelt; Rauls, Eva; Samal, Michal; Stary, Ivo; Muellegger, Stefan; Nejedly, Jindrich (Peer reviewed; Journal article, 2022)
      Dielectric relaxation lies at the heart of well-established techniques of dielectric spectroscopy essential to diverse fields of research and technology. We report an experimental route for increasing the sensitivity of ...

    • Towards learning optimized kernels for complex Langevin 

      Alvestad, Daniel; Larsen, Rasmus Normann; Rothkopf, Alexander Karl (Peer reviewed; Journal article, 2023)
      We present a novel strategy aimed at restoring correct convergence in complex Langevin simulations. The central idea is to incorporate system-specific prior knowledge into the simulations, in order to circumvent the NP-hard ...

    • Towards the nucleon hadronic tensor from lattice QCD 

      Liang, Jian; Draper, Terrence; Liu, Keh-Fei; Rothkopf, Alexander Karl; Yang, Yi-Bo (Peer reviewed; Journal article, 2020-06)
      We present the first calculation of the hadronic tensor on the lattice for the nucleon. The hadronic tensor can be used to extract structure functions in deep inelastic scatterings and to provide information for neutrino-nucleon ...

    • Transmission in pseudospin-1 and pseudospin-3/2 semimetals with linear dispersion through scalar and vector potential barriers 

      Mandal, Ipsita (Peer reviewed; Journal article, 2020-09)
      We investigate the tunneling of pseudospin-1 and pseudospin-3/2 quasiparticles through a barrier consisting of both electrostatic and vector potentials, existing uniformly in a finite region along the transmission axis. ...

    • Transport Properties of Superfluid Phonons in Neutron Stars 

      Manuel, Cristina; Tolos Rigueiro, Laura (Peer reviewed; Journal article, 2021-03)
      We review the effective field theory associated with the superfluid phonons that we use for the study of transport properties in the core of superfluid neutrons stars in their low temperature regime. We then discuss the ...

    • Tunneling in Fermi systems with quadratic band crossing points 

      Mandal, Ipsita (Peer reviewed; Journal article, 2020-08)
      We investigate the tunneling of quasiparticles through a rectangular potential barrier of finite height and width, in 2d and 3d semimetals with band structures consisting of a quadratic band crossing point. We compute the ...

    • Universal Black Holes 

      Hervik, Sigbjørn; Ortaggio, Marcello (Peer reviewed; Journal article, 2020-02)
      We prove that a generalized Schwarzschild-like ansatz can be consistently employed to construct d-dimensional static vacuum black hole solutions in any metric theory of gravity for which the Lagrangian is a scalar invariant ...

    • Universal spacetimes in four dimensions 

      Hervik, Sigbjørn; Pravda, Vojtech; Pravdova, Alena (Journal article; Peer reviewed, 2017-10)
      Universal spacetimes are exact solutions to all higher-order theories of gravity. We study these spacetimes in four dimensions and provide necessary and sufficient conditions for universality for all Petrov types except ...

    • Wick-rotations of pseudo-Riemannian Lie groups 

      Helleland, Christer (Peer reviewed; Journal article, 2020)
      We study Wick-rotations of left-invariant metrics on Lie groups, using results from real GIT (Helleland and Hervik, 2018; Helleland and Hervik, 2019). An invariant for Wick-rotation of Lie groups is given, and we describe ...