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Related papers: Hard Loops, Soft Loops, and High Density Effective…

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At sufficiently small $x$ where pQCD methods become insufficient we rewrote sum of dominant Feynman diagrams for single-scale hard processes in the form of the effective field theory where a quasiparticle corresponds to pQCD ladder. We…

High Energy Physics - Phenomenology · Physics 2016-09-06 B. Blok , L. Frankfurt

We analyze constraints from perturbative unitarity and crossing on the leading contributions of higher-dimension operators to the four-graviton amplitude in four spacetime dimensions, including constraints that follow from distinct helicity…

High Energy Physics - Theory · Physics 2022-05-03 Zvi Bern , Dimitrios Kosmopoulos , Alexander Zhiboedov

We develop a theory of superconductivity (or superfluidity) based on condensed fermion quartets focusing on the dilute spin-$\frac{1}{2}$ systems at zero temperature. In the spirit of the Bardeen--Cooper--Schrieffer ansatz, a variational…

Superconductivity · Physics 2026-05-29 Qiao-Ru Xu , Congjun Wu

Decoupling of heavy quarks at low energies can be described by means of an effective theory as shown by S. Weinberg in Ref. [1]. We study the decoupling of the charm quark by lattice simulations. We simulate a model, QCD with two degenerate…

High Energy Physics - Lattice · Physics 2017-11-22 Francesco Knechtli , Tomasz Korzec , Björn Leder , Graham Moir

QCD at fixed baryon number can be formulated in terms of transfer matrices explicitly defined in the canonical sectors. In the heavy-dense limit, the fermionic contributions to the canonical partition functions in terms of Polyakov loops…

High Energy Physics - Lattice · Physics 2021-10-29 Patrick Bühlmann , Urs Wenger

We show that the effective field theory of low energy modes in dense QCD has positive Euclidean path integral measure. The complexity of the measure of QCD at finite chemical potential can be ascribed to modes which are irrelevant to the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Deog Ki Hong , Stephen D. H. Hsu

The high density effective theory recently introduced by Hong and Hsu to describe ultradense relativistic fermionic matter is used to calculate the tree-level forward scattering amplitude between two particles at the Fermi surface. While…

High Energy Physics - Phenomenology · Physics 2009-11-10 Simon Hands

The success of the experimental program at the Tevatron re-inforced the idea that precision physics at hadron colliders is desirable and, indeed, possible. The Tevatron data strongly suggests that one-loop computations in QCD describe hard…

High Energy Physics - Phenomenology · Physics 2015-05-28 R. Keith Ellis , Zoltan Kunszt , Kirill Melnikov , Giulia Zanderighi

The generating functional for hard thermal loops in QCD is important in setting up a resummed perturbation theory. I review how this functional is related to the eikonal for a Chern-Simons theory, and using an auxiliary field, to the gauged…

High Energy Physics - Theory · Physics 2007-05-23 V. P. Nair

We argue that at sufficiently small Bjorken $x$ where pQCD amplitude rapidly increases with energy and violates probability conservation the shadowing effects in the single-scale small $x$ hard QCD processes can be described by an effective…

High Energy Physics - Phenomenology · Physics 2008-11-26 B. Blok , L. Frankfurt

Naive intuition about scale decoupling breaks down in the presence of fermion masses. Kinematic enhancements can greatly extend the range where one needs to keep a finite mass in calculations to obtain a correct result at even the O(1)…

High Energy Physics - Phenomenology · Physics 2024-09-19 Matthew Baumgart , Panagiotis Christeas

We develop a version of Soft Collinear Effective Theory (SCET) which includes finite quark masses, as well as Glauber gluons that describe the interaction of collinear partons with QCD matter. In the framework of this new effective field…

High Energy Physics - Phenomenology · Physics 2017-04-07 Zhong-Bo Kang , Felix Ringer , Ivan Vitev

Using methods of effective field theory, a systematic analysis of the fragmentation functions D_{a/H}(x,m_Q) of a hadron H containing a heavy quark Q is performed (with a=Q,Q_bar,q,q_bar,g). By integrating out pair production of virtual and…

High Energy Physics - Phenomenology · Physics 2007-06-15 Matthias Neubert

The properties of matter at finite baryon densities play an important role for the astrophysics of compact stars as well as for heavy ion collisions or the description of nuclear matter. Because of the sign problem of the quark determinant,…

High Energy Physics - Lattice · Physics 2017-04-05 Owe Philipsen

The axion is much lighter than all other degrees of freedom introduced by the Peccei-Quinn mechanism to solve the strong CP problem. It is therefore natural to use an effective field theory (EFT) to describe its interactions. Loop processes…

High Energy Physics - Phenomenology · Physics 2021-07-28 Gonzalo Alonso-Álvarez , Fatih Ertas , Joerg Jaeckel , Felix Kahlhoefer , Lennert J. Thormaehlen

Complimenting recent work on the effective field theory of cosmological large scale structures, here we present detailed approximate analytical results and further pedagogical understanding of the method. We start from the collisionless…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-02 Mark P. Hertzberg

We review recent theoretical developments in heavy quarkonium physics from the point of view of Effective Field Theories of QCD. We discuss Non-Relativistic QCD and concentrate on potential Non-Relativistic QCD. Our main goal will be to…

High Energy Physics - Phenomenology · Physics 2008-11-26 Nora Brambilla , Antonio Pineda , Joan Soto , Antonio Vairo

Effective field theory is applied to finite-density systems with an unnaturally large scattering length, such as neutron matter. A new organizational scheme is identified and connected with an expansion in inverse powers of the number of…

Nuclear Theory · Physics 2007-05-23 James V. Steele

We examine the equilibrium properties of hot, dilute, non-relativistic plasmas. The partition function and density correlation functions of a classical plasma with several species are expressed in terms of a functional integral over…

Plasma Physics · Physics 2009-10-31 Lowell S. Brown , Laurence G. Yaffe

A general effective action for quark matter at nonzero temperature and/or nonzero density is derived. Irrelevant quark modes are distinguished from relevant quark modes, and hard from soft gluon modes, by introducing two separate cut-offs…

Nuclear Theory · Physics 2017-08-23 P. T. Reuter , Q. Wang , D. H. Rischke