English
Related papers

Related papers: Three-loop HTL Free Energy for QED

200 papers

We compute higher order contributions to the free energy of noncommutative quantum electrodynamics at a nonzero temperature $T$. Our calculation includes up to three-loop contributions (fourth order in the coupling constant $e$). In the…

High Energy Physics - Theory · Physics 2009-09-29 F. T. Brandt , J. Frenkel , C. M. Muramoto

We calculate the two-loop pressure of a plasma of quarks and gluons at finite temperature and chemical potential using the hard thermal loop perturbation theory (HTLpt) reorganization of finite temperature/density quantum chromodynamics.…

High Energy Physics - Phenomenology · Physics 2013-05-10 Najmul Haque , Munshi G. Mustafa , Michael Strickland

In this proceedings we present a state-of-the-art method of calculating thermodynamic potential at finite temperature and finite chemical potential, using Hard Thermal Loop perturbation theory (HTLpt) up to next-to-next-leading-order…

High Energy Physics - Phenomenology · Physics 2016-03-03 Aritra Bandyopadhyay , Najmul Haque , Munshi G. Mustafa , Michael Strickland , Nan Su

Naively resummed perturbative approximations to the thermodynamic functions of QCD do not converge at phenomenologically relevant temperatures. Here we review recent results of a three-loop hard-thermal-loop perturbation theory calculation…

High Energy Physics - Phenomenology · Physics 2011-05-27 Michael Strickland , Jens O. Andersen , Lars E. Leganger , Nan Su

Effective-field-theory methods are used to separate the free energy for a nonabelian gauge theory at high temperature $T$ into the contributions from the momentum scales $T$, $gT$, and $g^2T$, where $g$ is the coupling constant at the scale…

High Energy Physics - Phenomenology · Physics 2009-07-09 Eric Braaten , Agustin Nieto

The free energy for QCD at high temperature $T$ is calculated to order $g^5$ using effective-field-theory methods to separate the contributions from the momentum scales $T$ and $gT$. The effects of the scale $T$ enter through the…

High Energy Physics - Phenomenology · Physics 2016-08-24 Eric Braaten , Agustin Nieto

We reconsider the two-loop electron self-energy in quantum electrodynamics. We present a modern calculation, where all relevant two-loop integrals are expressed in terms of iterated integrals of modular forms. As boundary points of the…

High Energy Physics - Phenomenology · Physics 2024-08-22 Ina Hönemann , Kirsten Tempest , Stefan Weinzierl

We consider our recently obtained general structure of two point (self-energy and propagator) functions of quarks and gluons in a nontrivial background like a heat bath and an external magnetic field. Based on this, here we have computed…

High Energy Physics - Phenomenology · Physics 2019-09-02 Aritra Bandyopadhyay , Bithika Karmakar , Najmul Haque , Munshi G. Mustafa

We compute the photon self-energy to three loops in Quantum Electrodynamics. The method of differential equations for Feynman integrals and a complete $\epsilon$-factorization of the former allow us to obtain fully analytical results in…

High Energy Physics - Theory · Physics 2025-12-15 Felix Forner , Christoph Nega , Lorenzo Tancredi

We discuss resummation strategies for free energy in quantum field theories at nonzero temperatures T. We point out that resummations should be performed for the short- and long-distance parts separately in order to avoid spurious…

High Energy Physics - Phenomenology · Physics 2009-11-07 G. Cvetic , R. Koegerler

We have developed a new simulation algorithm for free-energy calculations. The method is a multidimensional extension of the replica-exchange method. While pairs of replicas with different temperatures are exchanged during the simulation in…

Statistical Mechanics · Physics 2009-10-31 Yuji Sugita , Akio Kitao , Yuko Okamoto

I show how to compute the exact one-loop thermal correction to the free energy of a soliton. The method uses the effective potential as an auxiliary step to ensure that the soliton is quantized around the appropriate vacuum. The exact…

High Energy Physics - Theory · Physics 2009-11-07 N. Graham

The successive perturbative estimates of the pressure of QCD at high temperature T show no sign of convergence, unless the coupling constant g is unrealistically small. Exploiting known results of an effective field theory which separates…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. -P. Blaizot , E. Iancu , A. Rebhan

A new method is proposed for the calculation of the free energy of an N-component Phi^4 theory at finite temperature. The method combines a perturbative treatment of the hard modes with a non-perturbative treatment in the effectively…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stefan Leupold

Scalar QED is used to study approximations in thermal field theory beyond the Hard Thermal Loop resummation scheme. For this purpose the photon self energy is calculated for external momenta of the order e^2T using Hard Thermal Loop…

High Energy Physics - Phenomenology · Physics 2009-10-31 Stefan Leupold , Markus H. Thoma

We discuss the hard dense loop perturbation theory approach for studying the thermodynamics of strongly magnetized dense quark matter. The free energy of quarks and gluons have been calculated for one-loop quark and gluon self-energies,…

Nuclear Theory · Physics 2025-07-01 Sarthak Satapathy , Sumit , Salman Ahamad Khan

In this review some recent multi-loop results obtained in the framework of perturbative Quantum Chromodynamics (QCD) and Quantum Electrodynamics (QED) are discussed. After reviewing the most advanced techniques used for the computation of…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Steinhauser

Starting from a nonperturbative expression for entropy and density obtained from $\Phi$-derivable two-loop approximations to the thermodynamic potential, a quasiparticle model for the thermodynamics of QCD can be developed which…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Rebhan

Using an approach developed in the context of zero-temperature QCD to systematically sum higher order effects whose form is fixed by the renormalization group equation, we sum to all orders the leading log (LL) and next-to-leading log (NLL)…

High Energy Physics - Phenomenology · Physics 2009-11-07 D. G. C. McKeon , A. Rebhan

We compute the next-to-leading order (NLO) hard correction to the gluon self-energy tensor with arbitrary soft momenta in a hot and/or dense weakly coupled plasma in Quantum Chromodynamics. Our diagrammatic computations of the two-loop and…

High Energy Physics - Phenomenology · Physics 2023-11-14 Tyler Gorda , Risto Paatelainen , Saga Säppi , Kaapo Seppänen