52,151 research outputs found
General Formulation of Quantum Analysis
A general formulation of noncommutative or quantum derivatives for operators
in a Banach space is given on the basis of the Leibniz rule, irrespective of
their explicit representations such as the G\^ateaux derivative or commutators.
This yields a unified formulation of quantum analysis, namely the invariance of
quantum derivatives, which are expressed by multiple integrals of ordinary
higher derivatives with hyperoperator variables. Multivariate quantum analysis
is also formulated in the present unified scheme by introducing a partial inner
derivation and a rearrangement formula. Operator Taylor expansion formulas are
also given by introducing the two hyperoperators and with the inner derivation .
Physically the present noncommutative derivatives express quantum fluctuations
and responses.Comment: Latex file, 29 pages, no figur
Absorption Probability of De Sitter Horizon for Massless Fields with Spin
The evaluation of the absorption coefficients are important for particle
emission caused by Hawking radiation. In the case of cosmological particle
emission from the event horizon in De Sitter space, it is known that the scalar
wave functions are solved in terms of Legendre functions. For fields with
higher spin, the solution has been examined with low frequency approximation.
We shows that the radial equations of the fields with spin and
can be solved analytically in terms of the hypergeometric functions. We
calculate the absorption probability using asymptotic expansion for high
frequency limit. It turns out that the absorption coefficients are universal to
all bosonic fields; They depend only on the angular momentum and not spin. In
the case of spin fermions, we can also find non-vanishing absorption
probability in contrast to the previously known result.Comment: 7 pages, Late
Large basis ab initio shell model investigation of 9-Be and 11-Be
We are presenting the first ab initio structure investigation of the loosely
bound 11-Be nucleus, together with a study of the lighter isotope 9-Be. The
nuclear structure of these isotopes is particularly interesting due to the
appearance of a parity-inverted ground state in 11-Be. Our study is performed
in the framework of the ab initio no-core shell model. Results obtained using
four different, high-precision two-nucleon interactions, in model spaces up to
9\hbar\Omega, are shown. For both nuclei, and all potentials, we reach
convergence in the level ordering of positive- and negative-parity spectra
separately. Concerning their relative position, the positive-parity states are
always too high in excitation energy, but a fast drop with respect to the
negative-parity spectrum is observed when the model space is increased. This
behavior is most dramatic for 11-Be. In the largest model space we were able to
reach, the 1/2+ level has dropped down to become either the first or the second
excited state, depending on which interaction we use. We also observe a
contrasting behavior in the convergence patterns for different two-nucleon
potentials, and argue that a three-nucleon interaction is needed to explain the
parity inversion. Furthermore, large-basis calculations of 13-C and 11-B are
performed. This allows us to study the systematics of the position of the first
unnatural-parity state in the N=7 isotone and the A=11 isobar. The 11-B run in
the 9\hbar\Omega model space involves a matrix with dimension exceeding 1.1 x
10^9, and is our largest calculation so far. We present results on binding
energies, excitation spectra, level configurations, radii, electromagnetic
observables, and 10-Be+n overlap functions.Comment: 17 pages, 12 figures To be published in Phys. Rev. C Resubmitted
version. Minor change
Evaluation of Periods via Fibrations in Seiberg-Witten Theories and in Type-II String
We show how to evaluate the periods in Seiberg-Witten theories and in
K3-fibered Calabi-Yau manifolds by using fibrations of the theories. In the
Seiberg-Witten theories, it is shown that the dual pair of fields can be
constructed from the classical fields in a simple form. As for Calabi-Yau
manifolds which are fibrations of K3 surface, we obtain the solutions of the
Picard-Fuchs equations from the periods of K3 surface. By utilizing the
expression of periods for two-parameter models of type-II string, we derive the
solutions of the Picard-Fuchs equations around the points of enhanced gauge
symmetry and show a simple connection to the SU(2) Seiberg-Witten theory.Comment: 16 pages, Latex, no figures, a reference correcte
BPS Analysis of the Charged Soliton Solutions of D-brane Worldvolume Theory from the Viewpoint of Target-space Supersymmetry
We investigate BPS properties of the charged soliton solutions of D-brane
worldvolume theory, which is described by the supersymmetric Dirac-Born-Infeld
action, by means of the N=2 target-space supersymmetry algebra. Our results
agree with those obtained previously. We also extend our BPS analysis to the
case where axion background exists.Comment: 11 pages, LaTeX, 3 eps figures, v2: references corrected, a note
added, minor changes, v3: references corrected, notes added, equations added,
discussions adde
Classically Integrable Cosmological Models with a Scalar Field
New classes of classically integrable models in the cosmological theories
with a scalar field are obtained by using freedoms of defining time and fields.
In particular, some models with the sum of exponential potentials in the flat
spatial metric are shown to be integrable. The model with the Sine-Gordon
potential can be solved in terms of analytic continuation of the non-periodic
Toda field theory.Comment: 10 pages, Late
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