141 research outputs found
Electronic Detection of Gravitational Disturbances and Collective Coulomb Interactions
The cross section for a gravitational wave antenna to absorb a graviton may
be directly expressed in terms of the non-local viscous response function of
the metallic crystal. Crystal viscosity is dominated by electronic processes
which then also dominate the graviton absorption rate. To compute this rate
from a microscopic Hamiltonian, one must include the full Coulomb interaction
in the Maxwell electric field pressure and also allow for strongly
non-adiabatic transitions in the electronic kinetic pressure. The view that the
electrons and phonons constitute ideal gases with a weak electron phonon
interaction is not sufficiently accurate for estimating the full strength of
the electronic interaction with a gravitational wave.Comment: 7 pages LaTeX 1 figure afig1.ep
Phase Coherence in Quantum Brownian Motion
The quantum theory of Brownian motion is discussed in the Schwinger version
wherein the notion of a coordinate moving forward in time is replaced by
two coordinates, moving forward in time and moving backward
in time. The role of the doubling of the degrees of freedom is illustrated for
the case of electron beam two slit diffraction experiments. Interference is
computed with and without dissipation (described by a thermal bath). The notion
of a dissipative interference phase, closely analogous to the Aharonov-Bohm
magnetic field induced phase, is explored.Comment: 12 pages, LaTeX, 2 Figure
Quantum dissipation induced noncommutative geometry
The quantum statistical dynamics of a position coordinate x coupled to a
reservoir requires theoretically two copies of the position coordinate within
the reduced density matrix description. One coordinate moves forward in time
while the other coordinate moves backward in time. It is shown that quantum
dissipation induces, in the plane of the forward and backward motions, a
noncommutative geometry. The noncommutative geometric plane is a consequence of
a quantum dissipation induced phase interference which is closely analogous to
the Aharanov-Bohm effect.Comment: 12 pages, 2 figure
Infrared gluons, intrinsic transverse momentum and rising total cross-sections
We discuss the infrared limit for soft gluon kt-resummation and relate it to
physical observables such as the intrinsic transverse momentum and the high
energy limit of total cross-sections.Comment: 8 pages, 6 figures, Presented at Hadron Structure '09, Tatranska
Strba, September 2009, Slovacchia, to be published in the Conference
Proceeding
Compact Lattice QED and the Coulomb Potential
The potential energy of a static charge distribution on a lattice is
rigorously computed in the standard compact quantum electrodynamic model. The
method used follows closely that of Weyl for ordinary quantum electrodynamics
in continuous space-time. The potential energy of the static charge
distribution is independent of temperature and can be calculated from the
lattice version of Poisson's equation. It is the usual Coulomb potential.Comment: 6 pages, includes one figure in Topdrawer, NUB 3054/9
Non-Commutative Geometry and Measurements of Polarized Two Photon Coincidence Counts
Employing Maxwell's equations as the field theory of the photon, quantum
mechanical operators for spin, chirality, helicity, velocity, momentum, energy
and position are derived. The photon ``Zitterbewegung'' along helical paths is
explored. The resulting non-commutative geometry of photon position and the
quantum version of the Pythagorean theorem is discussed. The distance between
two photons in a polarized beam of given helicity is shown to have a discrete
spectrum. Such a spectrum should become manifest in measurements of two photon
coincidence counts. The proposed experiment is briefly described.Comment: Latex, 13 pages, 3 figure
Photon Total Cross-sections
We discuss present predictions for the total and
cross-sections, highlighting why predictions differ. We present results from
the Eikonal Minijet Model and improved predictions based on soft gluon
resummation.Comment: 7 pages, 10 figures, LaTeX, requires espcrc2.sty, Talk presented by
G. Pancheri at PHOTON-2003, International Meeting on Structure and
Interactions of the Photon, Frascati, Italy, April 7-11, 200
Neutrino oscillations in a model with a source and detector
We study the oscillations of neutrinos in a model in which the neutrino is
coupled to a localized, idealized source and detector. By varying the spatial
and temporal resolution of the source and detector we are able to model the
full range of source and detector types ranging from coherent to incoherent. We
find that this approach is useful in understanding the interface between the
Quantum Mechanical nature of neutrino oscillations on the one hand and the
production and detection systems on the other hand. This method can easily be
extended to study the oscillations of other particles such as the neutral K and
B mesons. We find that this approach gives a reliable way to treat the various
ambiguities which arise when one examines the oscillations from a wave packet
point of view. We demonstrate that the conventional oscillation formula is
correct in the relativistic limit and that several recent claims of an extra
factor of 2 in the oscillation length are incorrect. We also demonstrate
explicitly that the oscillations of neutrinos which have separated spatially
may be "revived" by a long coherent measurement.Comment: 30 pages, 6 figures, Late
Modeling pion and proton total cross-sections at LHC
To settle the question whether the growth with energy is universal for
different hadronic total cross-sections, we present results from theoretical
models for pion-proton, proton-proton and proton-antiproton total
cross-sections. We show that present and planned experiments at LHC can
differentiate between different models, all of which are consistent with
presently available (lower energy) data. This study is also relevant for the
analysis of those very high energy cosmic ray data which require reliable
pion-proton total cross-sections as seeds. A preliminary study of the total
pion-pion cross-sections is also made.Comment: 18 pages, 5 figures, submitted to Physics Letters
Probing the Higgs Field Using Massive Particles as Sources and Detectors
In the Standard Model, all massive elementary particles acquire their masses
by coupling to a background Higgs field with a non-zero vacuum expectation
value. What is often overlooked is that each massive particle is also a source
of the Higgs field. A given particle can in principle shift the mass of a
neighboring particle. The mass shift effect goes beyond the usual perturbative
Feynman diagram calculations which implicitly assume that the mass of each
particle is rigidly fixed. Local mass shifts offer a unique handle on Higgs
physics since they do not require the production of on-shell Higgs bosons. We
provide theoretical estimates showing that the mass shift effect can be large
and measurable, especially near pair threshold, at both the Tevatron and the
LHC.Comment: 6 pages, no figures; Version 2 corrects some typographical errors of
factors of 2 in equations 14, 17, 18 and 19 (all of the same origin) and
mentions a linear collider as an interesting place to test the results of
this pape
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