10 research outputs found
Luminosities of High-Redshift Objects in an Accelerating Universe
The results from the Supernova Cosmology Project indicate a relation between
cosmic distance and redshift that corresponds to an accelerating Universe, and,
as a consequence, the presence of an energy component with negative pressure.
This necessitates a re-evaluation of such astrophysical luminosities that have
been derived through conventional redshift analyses of, e.g., gamma-ray bursts
and quasars. We have calculated corrected luminosity distances within two
scenarios; the standard one with a non-zero cosmological constant, and the more
recently proposed ``quintessence'', with a slowly evolving energy-density
component. We find luminosity corrections from +30 to -40 per cent for
redshifts with . This finding implicates that the SCP data do not, by
themselves, require a revision of the current, rather qualitative modeling of
gamma-ray bursts and quasar properties.Comment: RevTeX, 4 pages, 2 postscript figures, submitted to PR
Diquark Properties and the TOV Equations
We present various results from including diquark properties and the gap
equations into the TOV equations for compact quark objects. One such property
is the diquark form factor, which has a strong influence on various quantities.
We discuss the consequences for quark stars.Comment: 6 pages, 4 eps-figures; presented by S.F. at "Compact Stars and the
QCD Phase Diagram", NORDITA, Copenhagen, August 2001; to be published in the
proceeding
Preon Trinity - a new model of leptons and quarks
A new model for the substructure of quarks, leptons and weak gauge bosons is
discussed. It is based on three fundamental and absolutely stable spin-1/2
preons. Its preon flavour SU(3) symmetry leads to a prediction of nine quarks,
nine leptons and nine heavy vector bosons. One of the quarks has charge
, and is speculated to be the top quark (whose charge has not been
measured). The flavour symmetry leads to three conserved lepton numbers in all
known weak processes, except for some neutrinos, which might either oscillate
or decay. There is also a (Cabibbo) mixing of the and quarks due to an
internal preon-antipreon annihilation channel. An identical channel exists
inside the composite , leading to a relation between the Cabibbo and
Weinberg mixing angles.Comment: 12 pages Latex, no figures; to be published in the Proceedings of
Beyond 99, Tegernsee, Germany, June 199
Preon trinity : a schematic model of leptons, quarks and heavy vector bosons
Quarks, leptons and heavy vector bosons are suggested to be composed of stable spin- (1/2) preons, existing in three flavours, combined according to simple rules. Straightforward consequences of an SU(3) preon-flavour symmetry are the conservation of three lepton numbers, oscillations and decays between some neutrinos, and the mixing of the d and s quarks, as well as of the vector fields W0 and B0. We find a relation between the Cabibbo and Weinberg mixing angles, and predict new (heavy) leptons, quarks and vector bosons, some of which might be observable at the Fermilab Tevatron and the future CERN LHC. A heavy neutrino might even be visible in existing data from the CERN LEP facility.Validerad; 2002; 20061216 (ysko
SFM and STM topographic studies of carbon-based surfaces exposed to deuterium plasma
Godkänd; 1994; 20120626 (nils)</p
Higgs pain? Take a preon!
The Higgs mechanism is the favourite cure for the main problem with electroweak unification, namely how to reconcile a gauge theory with the need for massive gauge bosons. This problem does not exist in preon models for quark and lepton substructure with composite and s, which, consequently, also avoid all other theoretical complications and paradoxes with the Higgs mechanism. We present a new, minimal preon model, which explains the family structure, and predicts several new, heavy quarks, leptons and vector bosons. Our preons obey a phenomenological supersymmetry, but without so-called squarks and sleptons, since this SUSY is effective only on the composite scale.Godkänd; 1997; 20070415 (ysko