17,999 research outputs found
Neutral heavy lepton production at next high energy linear colliders
The discovery potential for detecting new heavy Majorana and Dirac neutrinos
at some recently proposed high energy colliders is discussed. These
new particles are suggested by grand unified theories and superstring-inspired
models. For these models the production of a single heavy neutrino is shown to
be more relevant than pair production when comparing cross sections and
neutrino mass ranges.
The process is calculated
including on-shell and off-shell heavy neutrino effects.
We present a detailed study of cross sections and distributions that shows a
clear separation between the signal and standard model contributions, even
after including hadronization effects.Comment: 4 pages including 15 figures, 1 table. RevTex. Accepted in Physical
Review
Relaxing to a three dimensional brane junction
We suggest a mechanism which leads to 3+1 space-time dimensions. The Universe
assumed to have nine spatial dimensions is regarded as a special nonlinear
oscillatory system -- a kind of Einstein solid. There are p-brane solutions
which manifest as phase oscillations separating different phase states. The
presence of interactions allows for bifurcations of higher dimensional spaces
to lower dimensional ones in the form of brane junctions. We argue this is a
natural way to select lower dimensions.Comment: RevTex, 5 pages; version to appear in Europhys. Let
Cosmology in the Universe with distance dependent Lorentz-violating bakground
We consider a cosmological setup with the inflaton field in the presence of a
redshift dependent Lorentz-violating time-like background to address the
inflationary regime and other phases of the Universe. We also show that the
regime of dark energy at large distances (low redshifts) is essentially
dominated by the presence of the Lorentz-violating background.Comment: 8 pages, no figure, Latex, to appear in AHE
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