This book contains articles by experts on the plasma phase of quantum chromodynamics, and the plasma phase of electroweak interactions. The former plasma phase is being tested at RHIC (Brookhaven), and has been tested at CERN. Both plasmas have played roles in the development of the Universe since the Big Bang. A third topic is that of the high density colour superconductive state of matter, which may be present in the core of neutron stars.
The SEWM2002 workshop, like the ones before, brought together theoretical physicists working on thermal field theory and, more generally, on (resummation) techniques for deriving effective actions based on QCD and the electroweak standard model of elementary particle physics, but describing nonstandard situations. The focus was on the temperature/chemical potential phase diagram of QCD, considered both analytically and with lattice gauge theory, equilibrium and nonequilibrium thermo field theory, and on heavy ion physics. Other related topics were “small x physics” in QCD, electroweak baryogenesis, inflation, and dark energy in the early universe.
The standard model (SM) of particle physics is a hugely successful theory of nature, but it is incomplete. E.g., it cannot explain finite SM neutrino masses or the origin of the primordial baryon asymmetry (BAU). One way to address such problems is to postulate the existence of new but hidden particles. This thesis studies such "hidden sectors" in two ways: 1) An effective theory approach, where electroweak (EW) and GeV scale portal effective theories (PETs) are constructed that couple the SM to a generic light hidden mediator of spin 0, 1⁄2, or 1. The EW scale PETs include all portal operators of dimension d≤5. The GeV scale PETs additionally include all leading order (LO) flavour changing portal operators of dimension d≤6,7. They are used to derive a LO PET chiral perturbation theory Lagrangian that describes hidden sector induced light meson transitions in fixed target experiments like NA62 or SHiP. 2) An investigation of the type-I seesaw model, which couples the SM to n≥2 sterile neutrinos that can generate a BAU via “leptogenesis”. It is shown that thermal and spectator effects can result in a sign-flip and strong relative enhancement of the BAU in high-scale leptogenesis with two hierarchical sterile neutrinos of vanishing initial abundance. Much lighter sterile neutrinos may be detected via lepton number violating (LNV) decays at colliders, but LNV decays could be suppressed relative to lepton number conserving decays for 't Hooft natural parameter choices. It is shown that the corresponding parameter space consists of three regions: (a)with unsuppressed LNV decays, (b)with suppressed LNV decays, (c)with suppressed and unsuppressed LNV decays.
This book contains articles by experts on the plasma phase of quantum chromodynamics, and the plasma phase of electroweak interactions. The former plasma phase is being tested at RHIC (Brookhaven), and has been tested at CERN. Both plasmas have played roles in the development of the Universe since the Big Bang. A third topic is that of the high density colour superconductive state of matter, which may be present in the core of neutron stars.
The physics of strongly interacting matter in an external magnetic field is presently emerging as a topic of great cross-disciplinary interest for particle, nuclear, astro- and condensed matter physicists. It is known that strong magnetic fields are created in heavy ion collisions, an insight that has made it possible to study a variety of surprising and intriguing phenomena that emerge from the interplay of quantum anomalies, the topology of non-Abelian gauge fields, and the magnetic field. In particular, the non-trivial topological configurations of the gluon field induce a non-dissipative electric current in the presence of a magnetic field. These phenomena have led to an extended formulation of relativistic hydrodynamics, called chiral magnetohydrodynamics. Hitherto unexpected applications in condensed matter physics include graphene and topological insulators. Other fields of application include astrophysics, where strong magnetic fields exist in magnetars and pulsars. Last but not least, an important new theoretical tool that will be revisited and which made much of the progress surveyed in this book possible is the holographic principle - the correspondence between quantum field theory and gravity in extra dimensions. Edited and authored by the pioneers and leading experts in this newly emerging field, this book offers a valuable resource for a broad community of physicists and graduate students.
