383 research outputs found
Inflating Brane inside hyper-spherically symmetric defects
Static and inflating brane world models are considered in -dimensions
with a non zero bulk cosmological constant and with a hyper-spherically
symmetric topological defect residing in the extra dimensions. Several
vacuum solutions can be constructed explicitely when the bulk and inflating
constants are non zero. We study how these solutions are deformed by the
presence of a global monopole for generic values of and a local monopole
for . New types of solutions, regular and periodic in the radial variable
relative to the extra dimensions, are constructed.Comment: 23 pages, 9 figures, results extended, references adde
The Born-Infeld Sphaleron
We study the SU(2) electroweak model in which the standard Yang-Mills
coupling is supplemented by a Born-Infeld term. The deformation of the
sphaleron and bisphaleron solutions due to the Born-Infeld term is investigated
and new branches of solutions are exhibited. Especially, we find a new branch
of solutions connecting the Born-Infeld sphaleron to the first solution of the
Kerner-Gal'tsov series.Comment: 8 pages, 5 Postscript figures; new results on Bisphalerons added;
minor modification
SU(5) Gravitating Monopoles
Spherically symmetric solutions of the SU(5) Einstein-Yang-Mills-Higgs system
are constructed using the harmonic map ansatz \cite{IS}. This way the problem
reduces to solving a set of ordinary differential equations for the appropriate
profile functions.Comment: 12 pages, 3 Figure
The 1-soliton in the SO(3) gauged Skyrme model with mass term
The solitons of the SO(3) gauged Skyrme model with no pion-mass potential
were studied in Refs. {nl,jmp}. Here, the effects of the inclusion of this
potential are studied. In contrast with the (ungauged) Skyrme model, where the
effect of this potential on the solitons is marginal, here it turns out to be
decisive, resulting in very different dependence of the energy as a function of
the Skyrme coupling constant.Comment: new title, typos corrected, LaTeX, 8 pages, 4 figure
Inflating branes inside abelian strings
We study a 6-dimensional brane world model with an abelian string residing in
the two extra dimensions. We study both static as well as inflating branes and
find analytic solutions for the case of trivial matter fields in the bulk. Next
to singular space-times, we also find solutions which are regular including
cigar-like universes as well as solutions with periodic metric functions. These
latter solutions arise if in a singular space-time a static brane is replaced
by an inflating brane. We determine the pattern of generic solutions for
positive, negative and zero bulk cosmological constant.Comment: 14 Latex pages, 11 postscript figures; references added, discussion
extended; reference adde
Non-abelian magnetic black strings versus black holes
We present dimensional pure magnetic Yang-Mills (YM) black strings (or
branes) induced by the dimensional Einstein-Yang-Mills-Dilaton black
holes. Born-Infeld version of the YM field makes our starting point which goes
to the standard YM field through a limiting procedure. The lifting from black
holes to black strings, (with less number of fields) is by adding an extra,
compact coordinate. This amounts to the change of horizon topology from
to a product structure. Our black string in dimensions is a
rather special one, with uniform Hawking temperature and non-asymptotically
flat structure. As the YM charge becomes large the string gets thinner to tend
into a breaking point and transform into a % dimensional black hole.Comment: 5 pages no figure; Final version to appear in EPJ
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