9,703 research outputs found
Nonlinear transforms of momenta and Planck scale limit
Starting with the generators of the Poincar\'e group for arbitrary mass (m)
and spin (s) a nonunitary transformation is implemented to obtain momenta with
an absolute Planck scale limit. In the rest frame (for ) the transformed
energy coincides with the standard one, both being . As the latter tends to
infinity under Lorentz transformations the former tends to a finite upper limit
where is the Planck length and the
mass-dependent nonleading terms vanish exactly for zero rest mass.The invariant
is conserved for the transformed momenta. The speed of light continues
to be the absolute scale for velocities. We study various aspects of the
kinematics in which two absolute scales have been introduced in this specific
fashion. Precession of polarization and transformed position operators are
among them. A deformation of the Poincar\'e algebra to the SO(4,1) deSitter one
permits the implementation of our transformation in the latter case. A
supersymmetric extension of the Poincar\'e algebra is also studied in this
context.Comment: 10 pages, no figures, corrected some typo
Canonical factorization and diagonalization of Baxterized braid matrices: Explicit constructions and applications
Braid matrices , corresponding to vector representations,
are spectrally decomposed obtaining a ratio for
the coefficient of each projector appearing in the decomposition. This
directly yields a factorization for the braid
matrix, implying also the relation .This is
achieved for for all and
also for various other interesting cases including the 8-vertex matrix.We
explain how the limits can be interpreted to provide
factorizations of the standard (non-Baxterized) braid matrices. A systematic
approach to diagonalization of projectors and hence of braid matrices is
presented with explicit constructions for
and various other cases
such as the 8-vertex one. For a specific nested sequence of projectors
diagonalization is obtained for all dimensions. In each factor our
diagonalization again factors out all dependence on the spectral parameter
as a diagonal matrix. The canonical property implemented in the
diagonalizers is mutual orthogonality of the rows. Applications of our
formalism to the construction of operators and transfer matrices are
indicated. In an Appendix our type of factorization is compared to another one
proposed by other authors.Comment: 38 pages, no figure
Computation of outflow rates from accretion disks around black holes
We self-consistently estimate the outflow rate from the accretion rates of an
accretion disk around a black hole in which both the Keplerian and the
sub-Keplerian matter flows simultaneously. While Keplerian matter supplies
soft-photons, hot sub-Keplerian matter supplies thermal electrons. The
temperature of the hot electrons is decided by the degree of inverse
Comptonization of the soft photons. If we consider only thermally-driven flows
from the centrifugal pressure-supported boundary layer around a black hole, we
find that when the thermal electrons are cooled down, either because of the
absence of the boundary layer (low compression ratio), or when the surface of
the boundary layer is formed very far away, the outflow rate is negligible. For
an intermediate size of this boundary layer the outflow rate is maximal. Since
the temperature of the thermal electrons also decides the spectral state of a
black hole, we predict that the outflow rate should be directly related to the
spectral state.Comment: 9 pages, 5 figure
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