19,727 research outputs found
Method of using photovoltaic cell using poly-N-vinylcarbazole complex Patent
Method of producing output voltage from photovoltaic cell using poly-N-vinyl carbazole complexed with iodin
An introduction to interactive sonification
The research field of sonification, a subset of the topic of auditory display, has developed rapidly in recent decades. It brings together interests from the areas of data mining, exploratory data analysis, human–computer interfaces, and computer music. Sonification presents information by using sound (particularly nonspeech), so that the user of an auditory display obtains a deeper understanding of the data or processes under investigation by listening
Renormalization Group and Effective Potential in Classically Conformal Theories
We derive a general formula for the RG improved effective (Coleman-Weinberg)
potential for classically conformal models, applying it to several examples of
physical interest, and in particular a model of QCD coupled via quarks to a
colorless scalar field. The closed form expressions allow us to discuss the
range of validity of the effective potential as well as the issue of `large
logarithms' in a way different from previous such analyses. Remarkably, in all
examples considered, convexity of the effective potential is restored by the RG
improvement, or otherwise the potential becomes unstable. In the former case,
symmetry breaking becomes unavoidable due to the appearance of an infrared
barrier , which hints at a so far unsuspected link between
and the scale of electroweak symmetry breaking.Comment: 17 pages, 2 figures, formulas corrected, references adde
Conformal Anomaly and Off-Shell Extensions of Gravity
The gauge dependence of the conformal anomaly for spin 3/2 and spin 2 fields
in non-conformal supergravities has been a long standing puzzle. In this Letter
we argue that the `correct' gauge choice is the one that follows from requiring
all terms that would imply a violation of the Wess-Zumino consistency condition
to be absent in the counterterm, because otherwise the usual link between the
anomaly and the one-loop divergence becomes invalid. Remarkably, the `good'
choice of gauge is the one that confirms our previous result that a complete
cancellation of conformal anomalies in D=4 can only be achieved for N-extended
(Poincar\'e) supergravities with
Conformal invariance from non-conformal gravity
We discuss the conditions under which classically conformally invariant
models in four dimensions can arise out of non-conformal (Einstein) gravity. As
an `existence proof' that this is indeed possible we show how to derive N=4
super Yang Mills theory with any compact gauge group G from non-conformal
gauged N=4 supergravity as a special flat space limit. We stress the role that
the anticipated UV finiteness of the (so far unknown) underlying theory of
quantum gravity would have to play in such a scheme, as well as the fact that
the masses of elementary particles would have to arise via quantum
gravitational effects which mimic the conformal anomalies of standard (flat
space) UV divergent quantum field theory.Comment: 18 page
Conformal Anomalies and Gravitational Waves
We argue that the presence of conformal anomalies in gravitational theories
can lead to observable modifications to Einstein's equations via the induced
anomalous effective actions, whose non-localities can overwhelm the smallness
of the Planck scale. The fact that no such effects have been seen in recent
cosmological or gravitational wave observations therefore imposes strong
restrictions on the field content of possible extensions of Einstein's theory:
all viable theories should have vanishing conformal anomalies. We then show
that a complete cancellation of conformal anomalies in D=4 for both the
invariant and the Euler (Gauss-Bonnet) invariant can only be achieved for
N-extended supergravities with , as well as for M theory compactified
to four dimensions.Comment: 4 page
Conformal Symmetry and the Standard Model
We re-examine the question of radiative symmetry breaking in the standard
model in the presence of right-chiral neutrinos and a minimally enlarged scalar
sector. We demonstrate that, with these extra ingredients, the hypothesis of
classically unbroken conformal symmetry, besides naturally introducing and
stabilizing a hierarchy, is compatible with all available data; in particular,
there exists a set of parameters for which the model may remain viable even up
to the Planck scale. The decay modes of the extra scalar field provide a unique
signature of this model which can be tested at LHC.Comment: 13 pages, 6 figures, version to be published in Phys. Lett.
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