1,188 research outputs found
Non-Unitary and Unitary Transitions in Generalized Quantum Mechanics, New Small Parameter and Information Problem Solving
Quantum Mechanics of the Early Universe is considered as deformation of a
well-known Quantum Mechanics. Similar to previous works of the author, the
principal approach is based on deformation of the density matrix with
concurrent development of the wave function deformation in the respective
Schr{\"o}dinger picture, the associated deformation parameter being interpreted
as a new small parameter. It is demonstrated that the existence of black holes
in the suggested approach in the end twice causes nonunitary transitions
resulting in the unitarity. In parallel this problem is considered in other
terms: entropy density, Heisenberg algebra deformation terms, respective
deformations of Statistical Mechanics, - all showing the identity of the basic
results. From this an explicit solution for Hawking's informaion paradox has
been derived.Comment: 18 page
Sensitivity of spherical gravitational-wave detectors to a stochastic background of non-relativistic scalar radiation
We analyze the signal-to-noise ratio for a relic background of scalar
gravitational radiation composed of massive, non-relativistic particles,
interacting with the monopole mode of two resonant spherical detectors. We find
that the possible signal is enhanced with respect to the differential mode of
the interferometric detectors. This enhancement is due to: {\rm (a)} the
absence of the signal suppression, for non-relativistic scalars, with respect
to a background of massless particles, and {\rm (b)} for flat enough spectra, a
growth of the signal with the observation time faster than for a massless
stochastic background.Comment: four pages, late
Intermediate-mass-ratio-inspirals in the Einstein Telescope. II. Parameter estimation errors
We explore the precision with which the Einstein Telescope (ET) will be able
to measure the parameters of intermediate-mass-ratio inspirals (IMRIs). We
calculate the parameter estimation errors using the Fisher Matrix formalism and
present results of a Monte Carlo simulation of these errors over choices for
the extrinsic parameters of the source. These results are obtained using two
different models for the gravitational waveform which were introduced in paper
I of this series. These two waveform models include the inspiral, merger and
ringdown phases in a consistent way. One of the models, based on the transition
scheme of Ori & Thorne [1], is valid for IMBHs of arbitrary spin, whereas the
second model, based on the Effective One Body (EOB) approach, has been
developed to cross-check our results in the non-spinning limit. In paper I of
this series, we demonstrated the excellent agreement in both phase and
amplitude between these two models for non-spinning black holes, and that their
predictions for signal-to-noise ratios (SNRs) are consistent to within ten
percent. We now use these models to estimate parameter estimation errors for
binary systems with masses 1.4+100, 10+100, 1.4+500 and 10+500 solar masses
(SMs), and various choices for the spin of the central intermediate-mass black
hole (IMBH). Assuming a detector network of three ETs, the analysis shows that
for a 10 SM compact object (CO) inspiralling into a 100 SM IMBH with spin
q=0.3, detected with an SNR of 30, we should be able to determine the CO and
IMBH masses, and the IMBH spin magnitude to fractional accuracies of 0.001,
0.0003, and 0.001, respectively. We also expect to determine the location of
the source in the sky and the luminosity distance to within 0.003 steradians,
and 10%, respectively. We also assess how the precision of parameter
determination depends on the network configuration.Comment: 21 pages, 5 figures. One reference corrected in v3 for consistency
with published version in Phys Rev
Covariant Helicity-Coupling Amplitudes: A New Formulation
We have worked out covariant amplitudes for any two-body decay of a resonance
with an arbitrary non-zero mass, which involves arbitrary integer spins in the
initial and the final states. One key new ingredient for this work is the
application of the total intrinsic spin operator which is given
directly in terms of the generators of the Poincar\'e group.
Using the results of this study, we show how to explore the Lorentz factors
which appear naturally, if the momentum-space wave functions are used to form
the covariant decay amplitudes. We have devised a method of constructing our
covariant decay amplitudes, such that they lead to the Zemach amplitudes when
the Lorentz factors are set one
Pure States, Mixed States and Hawking Problem in Generalized Quantum Mechanics
This paper is the continuation of a study into the information paradox
problem started by the author in his earlier works. As previously, the key
instrument is a deformed density matrix in quantum mechanics of the early
universe. It is assumed that the latter represents quantum mechanics with
fundamental length. It is demonstrated that the obtained results agree well
with the canonical viewpoint that in the processes involving black holes pure
states go to the mixed ones in the assumption that all measurements are
performed by the observer in a well-known quantum mechanics. Also it is shown
that high entropy for Planck remnants of black holes appearing in the
assumption of the Generalized Uncertainty Relations may be explained within the
scope of the density matrix entropy introduced by the author previously. It is
noted that the suggested paradigm is consistent with the Holographic Principle.
Because of this, a conjecture is made about the possibility for obtaining the
Generalized Uncertainty Relations from the covariant entropy bound at high
energies in the same way as R. Bousso has derived Heisenberg uncertainty
principle for the flat space.Comment: 12 pages,no figures,some corrections,new reference
Gravitational radiative corrections from effective field theory
In this paper we construct an effective field theory (EFT) that describes
long wavelength gravitational radiation from compact systems. To leading order,
this EFT consists of the multipole expansion, which we describe in terms of a
diffeomorphism invariant point particle Lagrangian. The EFT also systematically
captures "post-Minkowskian" corrections to the multipole expansion due to
non-linear terms in general relativity. Specifically, we compute long distance
corrections from the coupling of the (mass) monopole moment to the quadrupole
moment, including up to two mass insertions. Along the way, we encounter both
logarithmic short distance (UV) and long wavelength (IR) divergences. We show
that the UV divergences can be (1) absorbed into a renormalization of the
multipole moments and (2) resummed via the renormalization group. The IR
singularities are shown to cancel from properly defined physical observables.
As a concrete example of the formalism, we use this EFT to reproduce a number
of post-Newtonian corrections to the gravitational wave energy flux from
non-relativistic binaries, including long distance effects up to 3PN ()
order. Our results verify that the factorization of scales proposed in the NRGR
framework of Goldberger and Rothstein is consistent up to order 3PN.Comment: 37 pages, LaTeX. Published versio
The Universe as a Nonuniform Lattice in the Finite-Dimensional Hypercube II.Simple Cases of Symmetry Breakdown and Restoration
This paper continues a study of field theories specified for the nonuniform
lattice in the finite-dimensional hypercube with the use of the earlier
described deformation parameters. The paper is devoted to spontaneous breakdown
and restoration of symmetry in simple quantum-field theories with scalar
fields. It is demonstrated that an appropriate deformation opens up new
possibilities for symmetry breakdown and restoration. To illustrate, at low
energies it offers high-accuracy reproducibility of the same results as with a
nondeformed theory. In case of transition from low to higher energies and vice
versa it gives description for new types of symmetry breakdown and restoration
depending on the rate of the deformation parameter variation in time, and
indicates the critical points of the previously described lattice associated
with a symmetry restoration. Besides, such a deformation enables one to find
important constraints on the initial model parameters having an explicit
physical meaning.Comment: 9 pages,Revte
Nonrenormalization theorems for N=2 Super Yang-Mills
The BRST algebraic proofs of the the nonrenormalization theorems for the beta
functions of N=2 and N=4 Super Yang-Mills theories are reviewed.Comment: 3 pages, contribution to SUSY 2000 Encyclopedi
Symmetries and Observables for BF-theories in Superspace
The supersymmetric version of a topological quantum field theory describing
flat connections, the super BF-theory, is studied in the superspace formalism.
A set of observables related to topological invariants is derived from the
curvature of the superspace. Analogously to the non-supersymmetric versions,
the theory exhibits a vector-like supersymmetry. The role of the vector
supersymmetry and an additional new symmetry of the action in the construction
of observables is explained.Comment: 11 pages, LaTe
Deformed Density Matrix and Generalized Uncertainty Relation in Thermodynamics
A generalization of the thermodynamic uncertainty relations is proposed. It
is done by introducing of an additional term proportional to the interior
energy into the standard thermodynamic uncertainty relation that leads to
existence of the lower limit of inverse temperature. The authors are of the
opinion that the approach proposed may lead to proof of these relations. To
this end, the statistical mechanics deformation at Planck scale. The
statistical mechanics deformation is constructed by analogy to the earlier
quantum mechanical results. As previously, the primary object is a density
matrix, but now the statistical one. The obtained deformed object is referred
to as a statistical density pro-matrix. This object is explicitly described,
and it is demonstrated that there is a complete analogy in the construction and
properties of quantum mechanics and statistical density matrices at Plank scale
(i.e. density pro-matrices). It is shown that an ordinary statistical density
matrix occurs in the low-temperature limit at temperatures much lower than the
Plank's. The associated deformation of a canonical Gibbs distribution is given
explicitly.Comment: 15 pages,no figure
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