25,268 research outputs found
Interpretation of Quantum Field Theories with a Minimal Length Scale
It has been proposed that the incorporation of an observer independent
minimal length scale into the quantum field theories of the standard model
effectively describes phenomenological aspects of quantum gravity. The aim of
this paper is to interpret this description and its implications for scattering
processes.Comment: replaced with published versio
Higgs Boson in RG running Inflationary Cosmology
An intriguing hypothesis is that gravity may be non-perturbatively
renormalizable via the notion of asymptotic safety. We show that the Higgs
sector of the SM minimally coupled to asymptotically safe gravity can generate
the observed near scale-invariant spectrum of the Cosmic Microwave Background
through the curvaton mechanism. The resulting primordial power spectrum places
an upper bound on the Higgs mass, which for finely tuned values of the curvaton
parameters, is compatible with the recently released Large Hadron Collider
data.Comment: 7 pages, no figur
Unified theory for external and internal attributes and symmetries of fundamental fermions
An unorthodox unified theory is developed to describe external and internal
attributes and symmetries of fundamental fermions, quarks and leptons. Basic
ingredients of the theory are an algebra which consists of all the
triple-direct-products of Dirac gamma-matrices and a triple-spinor-field,
called a triplet field, defined on the algebra. The algebra possesses three
commutative sub-algebras which describe, respectively, the external space-time
symmetry, the family structure and the internal color symmetry of quarks and
leptons. The triplet field includes threefold (fourfold) repetitionary modes of
spin 1/2 component fields with SU(3) (SU(4)) color symmetry. It is possible to
qualify the Yukawa interaction and to make a new interpretation of its coupling
constants naturally in an intrinsic mechanism of the triplet field formalism.
The Dirac mass matrices with quasi-democratic structure are derived as an
illustration
Theory of Complex Scattering Lengths
We derive a generalized Low equation for the T-matrix appropriate for complex
atom-molecule interaction. The properties of this new equation at very low
energies are studied and the complex scattering length and effective range are
derived.Comment: 9 page
The Solar Proton Burning Process Revisited In Chiral Perturbation Theory
The proton burning process p + p -> d + e(+) + \nu(e), important for the
stellar evolution of main-sequence stars of mass equal to or less than that of
the Sun, is computed in effective field theory using chiral perturbation
expansion to the next-to-next-to leading chiral order. This represents a
model-independent calculation consistent with low-energy effective theory of
QCD comparable in accuracy to the radiative np capture at thermal energy
previously calculated by first using very accurate two-nucleon wavefunctions
backed up by an effective field theory technique with a finite cut-off. The
result obtained thereby is found to support within theoretical uncertainties
the previous calculation of the same process by Bahcall and his co-workers.Comment: 30 pages, 2 eps files, aaspp4.sty needed, slightly modified, to be
published in Ap.
The resultant parameters of effective theory
This is the 4-th paper in the series devoted to a systematic study of the
problem of mathematically correct formulation of the rules needed to manage an
effective field theory. Here we consider the problem of constructing the full
set of essential parameters in the case of the most general effective
scattering theory containing no massless particles with spin J > 1/2. We
perform the detailed classification of combinations of the Hamiltonian coupling
constants and select those which appear in the expressions for renormalized
S-matrix elements at a given loop order.Comment: 21 pages, 4 LaTeX figures, submitted to Phys. Rev.
Six-dimensional Methods for Four-dimensional Conformal Field Theories
The calculation of both spinor and tensor Green's functions in
four-dimensional conformally invariant field theories can be greatly simplified
by six-dimensional methods. For this purpose, four-dimensional fields are
constructed as projections of fields on the hypercone in six-dimensional
projective space, satisfying certain transversality conditions. In this way
some Green's functions in conformal field theories are shown to have structures
more general than those commonly found by use of the inversion operator. These
methods fit in well with the assumption of AdS/CFT duality. In particular, it
is transparent that if fields on AdS approach finite limits on the boundary
of AdS, then in the conformal field theory on this boundary these limits
transform with conformal dimensionality zero if they are tensors (of any rank),
but with conformal dimension 1/2 if they are spinors or spinor-tensors.Comment: Version accepted for publication in Physical Review D. References to
earlier work added in footnote 2. Minor errors corrected. 24 page
Spontaneous violation of CP symmetry in the strong interactions
Some time ago Dashen pointed out that spontaneous CP violation can occur in
the strong interactions. I show how a simple effective Lagrangian exposes the
remarkably large domain of quark mass parameters for which this occurs. I close
with some warnings for lattice simulations.Comment: 10 pages, 1 figure; final version to appear in PR
II. The Standard Model in the Isotopic Foldy-Wouthuysen Representation without Higgs Bosons in the Fermion Sector. Spontaneous Breaking of Parity and "Dark Matter" Problems
The Standard Model with massive fermions is formulated in the isotopic
Foldy-Wouthuysen representation. SU(2)xU(1) - invariance of the theory in this
representation is independent of whether fermions possess mass or not, and,
consequently, it is not necessary to introduce interactions between Higgs
bosons and fermions. The study discusses a possible relation between
spontaneous breaking of parity in the isotopic Foldy-Wouthuysen representation
and the composition of elementary particles of "dark matter".Comment: 12 page
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