37,984 research outputs found
Is Alice burning or fuzzing?
Recently, Almheiri, Marolf, Polchinski and Sully (AMPS) have suggested a
Gedankenexperiment to test black hole complementarity. They claim that the
postulates of black hole complementarity are mutually inconsistent and choose
to give up the "absence of drama" for an infalling observer. According to them
the black hole is shielded by a firewall no later than Page time. This has
generated some controversy. We find that an interesting picture emerges when we
take into account objections from the advocates of fuzzballs. We reformulate
AMPS' Gedankenexperiment in the decoherence picture of quantum mechanics and
find that low energy wave packets interact with the radiation quanta rather
violently while high energy wave packets do not. This is consistent with
Mathur's recent proposal of fuzzball complementarity for high energy quanta
falling into fuzzballs.Comment: 14 pages, 6 figures; v3: References added, discussions of some parts
changed substantially, conclusions unaltere
W' signatures with odd Higgs particles
We point out that W' bosons may decay predominantly into Higgs particles
associated with their broken gauge symmetry. We demonstrate this in a
renormalizable model where the W' and W couplings to fermions differ only by an
overall normalization. This "meta-sequential" W' boson decays into a scalar
pair, with the charged one subsequently decaying into a W boson and a neutral
scalar. These scalars are odd under a parity of the Higgs sector, which
consists of a complex bidoublet and a doublet. The W' and Z' bosons have the
same mass and branching fractions into scalars, and may show up at the LHC in
final states involving one or two electroweak bosons and missing transverse
energy.Comment: 24 page
Solving the More Difficult Aspects of Electric Motor Thermal Analysis in Small and Medium Size Industrial Induction Motors
With the ever-increasing pressure on electric motor manufacturers to develop smaller and more efficient electric motors, there is a need for more thermal analysis in parallel with the traditional electromagnetic design. Attention to the thermal design can be rewarded by major improvements in the overall performance. Technical papers published to date highlight a number of thermal design issues that are difficult to analyze. This paper reviews some of these issues and gives advice on how to deal with them when developing algorithms for inclusion in design software
Companions of Qsos at Redshift 1.1
We discuss broad- and narrow-band imaging of 7 arcmin fields of 14 QSOs with
redshift ~1.1. The narrow-band filters were chosen to detect redshifted [O II]
3727A, and the broad bands are R and I, which correspond to rest wavelengths
{}~3300A and ~3800A. In 100 arcsec subfields surrounding the QSOs, we detect an
excess of typically 15 detected objects over the background of 25. Several of
the QSO subfields also contain an excess of blue (R-I < 1.0) galaxies compared
with the other subfields. Finally, several of the QSO subfields contain an
excess of galaxies with significant narrow-band flux compared with the other
subfields, and many of these are also blue. Most of the QSOs are radio-quiet in
a region of sky overpopulated with z=1.1 QSOs, and 3 others are radio-loud from
other parts of the sky. We suggest that most of these z=1.1 QSOs are in compact
groups of starbursting galaxies. In our data, there is no significant
difference between radio-loud and radio-quiet QSOs. We discuss cosmic
evolutionary implications.Comment: 9 pages Plain Tex, 8 figures upon request, SISSA-DAO-94-00
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