7,087 research outputs found
On p-Adic Sector of Adelic String
We consider construction of Lagrangians which are candidates for p-adic
sector of an adelic open scalar string. Such Lagrangians have their origin in
Lagrangian for a single p-adic string and contain the Riemann zeta function
with the d'Alembertian in its argument. In particular, we present a new
Lagrangian obtained by an additive approach which takes into account all p-adic
Lagrangians. The very attractive feature of this new Lagrangian is that it is
an analytic function of the d'Alembertian. Investigation of the field theory
with Riemann zeta function is interesting in itself as well.Comment: 10 pages. Presented at the 2nd Conf. on SFT and Related Topics,
Moscow, April 2009. Submitted to Theor. Math. Phy
Why does the clustering of haloes depend on their formation history
We discuss in the framework of the excursion set formalism a recent discovery
from N-body simulations that the clustering of haloes of given mass depends on
their formation history. We review why the standard implementation of this
formalism is unable to explain such dependencies, and we show that this can, in
principle, be rectified by implementing in full an ellipsoidal collapse model
where collapse depends not only on the overdensity but also on the shape of the
initial density field. We also present an alternative remedy for this
deficiency, namely the inclusion of collapse barriers for pancakes and
filaments, together with the assumption that formation history depends on when
these barriers are crossed. We implement both these extensions in a generalised
excursion set method, and run large Monte Carlo realisations to quantify the
effects. Our results suggest that effects as large as those found in
simulations can only arise in the excursion set formalism if the formation
history of a halo does indeed depend on the size of its progenitor filaments
and pancakes. We also present conditional distributions of progenitor pancakes
and filaments for low-mass haloes identified at present epoch, and discuss a
recent claim by Mo et.al. that most low-mass haloes were embedded in massive
pancakes at .Comment: 11 pages, 8 figures, submitted to MNRA
Toward Open-Closed String Theoretical Description of Rolling Tachyon
We consider how the time-dependent decay process of an unstable D-brane
should be described in the full (quantum) open-closed string theory. It is
argued that the system, starting from the unstable D-brane configuration, will
evolve in time into the time-independent open string tachyon vacuum
configuration which we assume to be finite, with the total energy conserved. As
a concrete realization of this idea, we construct a toy model describing the
open and closed string tachyons which admits such a time-dependent solution.
The structure of our model has some resemblance to that of open-closed string
field theory.Comment: 1+10 pages, 6 figures. v2: a reference adde
Nonlocal Dynamics of p-Adic Strings
We consider the construction of Lagrangians that might be suitable for
describing the entire -adic sector of an adelic open scalar string. These
Lagrangians are constructed using the Lagrangian for -adic strings with an
arbitrary prime number . They contain space-time nonlocality because of the
d'Alembertian in argument of the Riemann zeta function. We present a brief
review and some new results.Comment: 8 page
Zeta Nonlocal Scalar Fields
We consider some nonlocal and nonpolynomial scalar field models originated
from p-adic string theory. Infinite number of spacetime derivatives is
determined by the operator valued Riemann zeta function through d'Alembertian
in its argument. Construction of the corresponding Lagrangians L starts
with the exact Lagrangian for effective field of p-adic tachyon
string, which is generalized replacing p by arbitrary natural number n and then
taken a sum of over all n. The corresponding new objects we
call zeta scalar strings. Some basic classical field properties of these fields
are obtained and presented in this paper. In particular, some solutions of the
equations of motion and their tachyon spectra are studied. Field theory with
Riemann zeta function dynamics is interesting in its own right as well.Comment: 13 pages, submitted to Theoretical and Mathematical Physic
Frames of reference in spaces with affine connections and metrics
A generalized definition of a frame of reference in spaces with affine
connections and metrics is proposed based on the set of the following
differential-geometric objects:
(a) a non-null (non-isotropic) vector field,
(b) the orthogonal to the vector field sub space,
(c) an affine connection and the related to it covariant differential
operator determining a transport along the given non-null vector filed.
On the grounds of this definition other definitions related to the notions of
accelerated, inertial, proper accelerated and proper inertial frames of
reference are introduced and applied to some mathematical models for the
space-time. The auto-parallel equation is obtained as an Euler-Lagrange's
equation. Einstein's theory of gravitation appears as a theory for
determination of a special frame of reference (with the gravitational force as
inertial force) by means of the metrics and the characteristics of a material
distribution.
PACS numbers: 0490, 0450, 1210G, 0240VComment: 17 pages, LaTeX 2
Descent Relations and Oscillator Level Truncation Method
We reexamine the oscillator level truncation method in the bosonic String
Field Theory (SFT) by calculation the descent relation =Z_3<V_2|. For
the ghost sector we use the fermionic vertices in the standard oscillator
basis. We propose two new schemes for calculations. In the first one we assume
that the insertion satisfies the overlap equation for the vertices and in the
second one we use the direct calculations. In both schemes we get the correct
structures of the exponent and pre-exponent of the vertex <V_2|, but we find
out different normalization factors Z_3.Comment: 21 pages, 10 figures, Late
The Schrodinger Wave Functional and Closed String Rolling Tachyon
In this short note we apply Schrodinger picture description of the
minisuperspace approach to the closed string tachyon condensation. We will
calculate the rate of produced closed string and we will show that the density
of high massive closed string modes reaches the string density in time of order
one in string units.Comment: 12 page
Dual equivalence in models with higher-order derivatives
We introduce a class of higher-order derivative models in (2,1) space-time
dimensions. The models are described by a vector field, and contain a
Proca-like mass term which prevents gauge invariance. We use the gauge
embedding procedure to generate another class of higher-order derivative
models, gauge-invariant and dual to the former class. We show that the results
are valid in arbitrary (d,1) space-time dimensions when one discards the
Chern-Simons and Chern-Simons-like terms. We also investigate duality at the
quantum level, and we show that it is preserved in the quantum scenario. Other
results include investigations concerning the gauge embedding approach when the
vector field couples with fermionic matter, and when one adds nonlinearity.Comment: RevTex4, 14 pages; new version includes duality at the quantum level,
and new references. To be published in J. Phys.
Extended Weyl Calculus and Application to the Phase-Space Schr\"{o}dinger Equation
We show that the Schr\"{o}dinger equation in phase space proposed by
Torres-Vega and Frederick is canonical in the sense that it is a natural
consequence of the extended Weyl calculus obtained by letting the Heisenberg
group act on functions (or half-densities) defined on phase space. This allows
us, in passing, to solve rigorously the TF equation for all quadratic
Hamiltonians.Comment: To appear in J. Phys. A: Math. and genera
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