57 citations · 347 across the 23 of their papers we have counts for
24 papers
Resurgence and semiclassical expansion in two-dimensional large- sigma models
Hiromichi Nishimura, Toshiaki Fujimori, Tatsuhiro Misumi +2
The resurgence structure of the 2d sigma model at large is studied with a focus on an IR momentum cutoff scale that regularizes IR singularities in the semiclassical…
Deconfinement and CP-breaking at in Yang-Mills theories and a novel phase for SU(2)
Shi Chen, Kenji Fukushima, Hiromichi Nishimura +1
We discuss the deconfinement and the CP-breaking phase transitions at in Yang-Mills theories. The 't Hooft anomaly matching prohibits the confined phase with CP symmetry and…
Free energy of a Holonomous Plasma
Chris P. Korthals Altes, Hiromichi Nishimura, Robert D. Pisarski +1
At a nonzero temperature T, a constant field generates nontrivial eigenvalues of the thermal Wilson line. We discuss contributions to the free energy of s…
Conundrum for the free energy of a holonomous gluonic plasma at cubic order
Christiaan P. Korthals Altes, Hiromichi Nishimura, Robert D. Pisarski +1
We compute the term in the free energy for a gauge theory with nonzero holonomy at nonzero temperature. If the holonomy is generated kinematically by the introdu…
High-temperature domain walls of QCD with imaginary chemical potentials
Hiromichi Nishimura, Yuya Tanizaki
We study QCD with massless quarks on under symmetry-twisted boundary conditions with small compactification radius, i.e. at high temperatures. Under suitab…
Thermal effective potential for the Polyakov loop to higher loop order
Hiromichi Nishimura, Chris Korthals-Altes, Robert D. Pisarski +1
This is a progress report on the calculation of the effective potential for the Polyakov loop in pure gauge theory beyond two-loop order. We introduce a new approach using…
Possible higher order phase transition in large- gauge theory at finite temperature
Hiromichi Nishimura, Robert D. Pisarski, Vladimir V. Skokov
We analyze the phase structure of gauge theory at finite temperature using matrix models. Our basic assumption is that the effective potential is dominated by double-t…
Finite-temperature phase transitions of third and higher order in gauge theories at large
Hiromichi Nishimura, Robert D. Pisarski, Vladimir V. Skokov
We study phase transitions in gauge theories at nonzero temperature using matrix models. Our basic assumption is that the effective potential is dominated by double tr…
Gradient flows without blow-up for Lefschetz thimbles
Yuya Tanizaki, Hiromichi Nishimura, Jacobus J. M. Verbaarschot
We propose new gradient flows that define Lefschetz thimbles and do not blow up in a finite flow time. We study analytic properties of these gradient flows, and confirm them by num…
Liquid-Gas Phase Transitions and Symmetry in Quantum Field Theories
Hiromichi Nishimura, Michael C. Ogilvie, Kamal Pangeni
A general field-theoretic framework for the treatment of liquid-gas phase transitions is developed. Starting from a fundamental four-dimensional field theory at nonzero temperature…
Complex spectrum of spin models for finite-density QCD
Hiromichi Nishimura, Michael Ogilvie, Kamal Pangeni
We consider the spectrum of transfer matrix eigenvalues associated with Polyakov loops in lattice QCD at strong coupling. The transfer matrix at finite density is non-Hermitian, an…
Complex spectrum of finite-density lattice QCD with static quarks at strong coupling
Hiromichi Nishimura, Michael C. Ogilvie, Kamal Pangeni
We calculate the spectrum of transfer matrix eigenvalues associated with Polyakov loops in finite-density lattice QCD with static quarks. These eigenvalues determine the spatial be…
Evading the sign problem in the mean-field approximation through Lefschetz-thimble path integral
Yuya Tanizaki, Hiromichi Nishimura, Kouji Kashiwa
The fermion sign problem appearing in the mean-field approximation is considered, and the systematic computational scheme of the free energy is devised by using the Lefschetz-thimb…
Gravitational collapse of thin shells: Time evolution of the holographic entanglement entropy
Ville Keranen, Hiromichi Nishimura, Stefan Stricker +2
We study the dynamics of gravitationally collapsing massive shells in AdS spacetime, and show in detail how one can determine extremal surfaces traversing them. The results are use…
Complex saddle points in finite-density QCD
Hiromichi Nishimura, Michael C. Ogilvie, Kamal Pangeni
We consider complex saddle points in QCD at finite temperature and density, which are constrained by symmetry under charge and complex conjugations. This approach naturally incorpo…
Complex Saddle Points and Disorder Lines in QCD at finite temperature and density
Hiromichi Nishimura, Michael C. Ogilvie, Kamal Pangeni
The properties and consequences of complex saddle points are explored in phenomenological models of QCD at non-zero temperature and density. Such saddle points are a consequence of…
Scalar field collapse with negative cosmological constant
R. Baier, Hiromichi Nishimura, S. A. Stricker
The formation of black holes or naked singularities is studied in a model in which a homogeneous time-dependent scalar field with an exponential potential couples to four dimension…
Transport coefficients of two-flavor superconducting quark matter
Mark G. Alford, Hiromichi Nishimura, Armen Sedrakian
Background: The two-flavor color superconducting (2SC) phase of quark matter is a possible constituent of the core of neutron stars. To assess its impact on the observable behavior…
Universality in holographic entropy production
Ville Keranen, Hiromichi Nishimura, Stefan Stricker +2
We consider the time evolution of two entropy-like quantities, the holographic entanglement entropy and causal holographic information, in a model of holographic thermalization dua…
Complex saddle points in QCD at finite temperature and density
Hiromichi Nishimura, Michael C. Ogilvie, Kamal Pangeni
The sign problem in QCD at finite temperature and density leads naturally to the consideration of complex saddle points of the action or effective action. The global symmetry $\mat…
Confinement in a Higgs Model on
Hiromichi Nishimura, Michael C. Ogilvie
We determine the phase structure of an SU(2) gauge theory with an adjoint scalar on using semiclassical methods. There are two global symmetries: a s…
Phase Structure of Confining Theories on R^3 x S^1
Hiromichi Nishimura, Michael C. Ogilvie
Recent work on QCD-like theories on R^3 x S^1 has revealed that a confined phase can exist when the circumference L of S^1 is sufficiently small. Adjoint QCD and double-trace defor…
PNJL model for adjoint fermions
Hiromichi Nishimura, Michael C. Ogilvie
Recent work on QCD-like theories has shown that the addition of adjoint fermions obeying periodic boundary conditions to gauge theories on R^3 X S^1 can lead to a restoration of ce…
A PNJL Model for Adjoint Fermions with Periodic Boundary Conditions
Hiromichi Nishimura, Michael C. Ogilvie
Recent work on QCD-like theories has shown that the addition of adjoint fermions obeying periodic boundary conditions to gauge theories on can lead to a restora…