9,716 research outputs found
Generalized q-deformed Correlation Functions as Spectral Functions of Hyperbolic Geometry
We analyse the role of vertex operator algebra and 2d amplitudes from the
point of view of the representation theory of infinite dimensional Lie
algebras, MacMahon and Ruelle functions. A p-dimensional MacMahon function is
the generating function of p-dimensional partitions of integers. These
functions can be represented as amplitudes of a two-dimensional c=1 CFT. In
this paper we show that p-dimensional MacMahon functions can be rewritten in
terms of Ruelle spectral functions, whose spectrum is encoded in the
Patterson-Selberg function of three dimensional hyperbolic geometry.Comment: 12 pages, no figure
An unified cosmological evolution driven by a mass dimension one fermionic field
An unified cosmological model for an Universe filled with a mass dimension
one (MDO) fermionic field plus the standard matter fields is considered. After
a primordial quantum fluctuation the field slowly rolls down to the bottom of a
symmetry breaking potential, driving the Universe to an inflationary regime
that increases the scale factor for about 71 e-folds. After the end of
inflation, the field starts to oscillate and can transfer its energy to the
standard model particles through a reheating mechanism. Such a process is
briefly discussed in terms of the admissible couplings of the MDO field with
the electromagnetic and Higgs fields. We show that even if the field loses all
its kinetic energy during reheating, it can evolve as dark matter due a
gravitational coupling (of spinorial origin) with baryonic matter. Since the
field acquires a constant value at the bottom of the potential, a non-null,
although tiny, mass term acts as a dark energy component nowadays. Therefore,
we conclude that MDO fermionic field is a good candidate to drive the whole
evolution of the Universe, in such a way that the inflationary field, dark
matter and dark energy are described by different manifestations of a single
field.Comment: 22 pages, 5 figure
Euclidean thermal spinor Green's function in the spacetime of a straight cosmic string
Within the framework of the quantum field theory at finite temperature on a
conical space, we determine the Euclidean thermal spinor Green's function for a
massless spinor field. We then calculate the thermal average of the
energy-momentum tensor of a thermal bath of massless fermions. In the
high-temperature limit, we find that the straight cosmic string does not
perturb the thermal bathComment: 11 pages, latex, no figure
Tratado internacional de recursos genéticos e suas implicações para o melhoramento genético de plantas.
O Tratado Internacional de Recursos Fitogenéticos para a Alimentação e Agricultura tem como objetivos principais a conservação e o uso dos recursos fitogenéticos para a alimentação e a agricultura, e a justa e eqüitativa distribuição dos benefÃcios que resultem de seu uso, isso feito em harmonia com a Convenção de Biodiversidade, para uma agricultura sustentável e para a segurança alimentar.Palestra
Operator Product on Locally Symmetric Spaces of Rank One and the Multiplicative Anomaly
The global multiplicative properties of Laplace type operators acting on
irreducible rank one symmetric spaces are considered. The explicit form of the
multiplicative anomaly is derived and its corresponding value is calculated
exactly, for important classes of locally symmetric spaces and different
dimensions.Comment: Int. Journal of Modern Physics A, vol. 18 (2003), 2179-218
Massive scalar field near a cosmic string
The function of a massive scalar field near a cosmic string is
computed and then employed to find the vacuum fluctuation of the field. The
vacuum expectation value of the energy-momentum tensor is also computed using a
point-splitting approach. The obtained results could be useful also for the
case of self-interacting scalar fields and for the finite-temperature Rindler
space theory.Comment: 15 pages, standard LaTeX, no figures. Reference [14] correcte
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