13,998 research outputs found
A Rigorous Proof of Fermi Liquid Behavior for Jellium Two-Dimensional Interacting Fermions
Using the method of continuous constructive renormalization group around the
Fermi surface, it is proved that a jellium two-dimensional interacting system
of Fermions at low temperature remains analytic in the coupling constant
for where is some numerical constant
and is the temperature. Furthermore in that range of parameters, the first
and second derivatives of the self-energy remain bounded, a behavior which is
that of Fermi liquids and in particular excludes Luttinger liquid behavior. Our
results prove also that in dimension two any transition temperature must be
non-perturbative in the coupling constant, a result expected on physical
grounds. The proof exploits the specific momentum conservation rules in two
dimensions.Comment: 4 pages, no figure
Interstellar helium in interplanetary space
The velocity distribution function of He(+) in the solar wind at 1 AU is calculated with the assumption that the source is photoionization of a cold (T = 100 K), neutral interstellar wind. If the spiral magnetic field is noise free, the velocity distribution is diffuse and would not produce a peak at 4(E over Q) sub H in an E over Q particle spectrum. If the velocity of the interstellar wind with respect to the sun lies in the ecliptic, a large variation of the He(+) number density with respect to ecliptic longitude is expected
Remarkable virtual SUSY effects in production at high energy hadron colliders
We present a complete 1-loop study of the electroweak corrections to the
process in MSSM and SM.
The occurrence of a number of remarkable properties in the behavior of the
helicity amplitudes at high energies is stressed, and the crucial role of the
virtual SUSY contributions in establishing them, is emphasized. The approach to
asymptopia of these amplitudes is discussed, comparing the effects of the
logarithmic and constant contributions to the mass suppressed ones, which are
relevant at lower energies. Applying crossing to , we obtain all
subprocesses needed for the 1-loop electroweak corrections to
-production at LHC. The SUSY model dependence of such a production is
then studied, and illustrations are given for the transverse momentum
distribution, as well as the angular distribution in the subprocess center of
mass.Comment: 21 pages, 12 figures, version to appear in Phys.Rev.
Ultralight reactive metal foams produced as structural shapes in space: System design
This autonomous experiment for foaming metals in space involved: (1) payload support structure; (2) furnace and foaming apparatus; (3) electronic controls; (4) battery power; and (5) metallurgy. Emphasis was laid on a modular design which was easily modifiable and which offered maximum durability, safety, and failure tolerance
Constructive Field Theory and Applications: Perspectives and Open Problems
In this paper we review many interesting open problems in mathematical
physics which may be attacked with the help of tools from constructive field
theory. They could give work for future mathematical physicists trained with
the constructive methods well within the 21st century
Fermionic functional renormalization group for first-order phase transitions: a mean-field model
First-order phase transitions in many-fermion systems are not detected in the
susceptibility analysis of common renormalization-group (RG) approaches. Here
we introduce a counterterm technique within the functional
renormalization-group (fRG) formalism which allows access to all stable and
metastable configurations. It becomes possible to study symmetry-broken states
which occur through first-order transitions as well as hysteresis phenomena.
For continuous transitions, the standard results are reproduced. As an example,
we study discrete-symmetry breaking in a mean-field model for a commensurate
charge-density wave. An additional benefit of the approach is that away from
the critical temperature for the breaking of discrete symmetries large
interactions can be avoided at all RG scales.Comment: 17 pages, 8 figures. v2 corrects typos, adds references and a
discussion of the literatur
A new culture method for biochemical studies of the circadian clock
A new culture method for biochemical studies of the circadian cloc
Circadian periodicity in acetate non-utilizing mutants
Circadian periodicity in acetate non-utilizing mutant
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