720 research outputs found
Law Behind Second Law of Thermodynamics --Unification with Cosmology--
In an abstract setting of a general classical mechanical system as a model
for the universe we set up a general formalism for a law behind the second law
of thermodynamics, i.e. really for "initial conditions". We propose a
unification with the other laws by requiring similar symmetry and locality
properties.Comment: 17 page
Prediction for Nonabelian Fine Structure Constants from Multicriticality
In developing a model for predicting the nonabelian gauge coupling constants
we argue for the phenomenological validity of a ``principle of multiple point
criticality''. This is supplemented with the assumption of an ``(grand)
anti-unified'' gauge group that, at the Planck scale, breaks down
to the diagonal subgroup. Here is the number of generations which is
assumed to be 3. According to this ``multiple point criticality principle'',
the Planck scale experimental couplings correspond to multiple point couplings
of the bulk phase transition of a lattice gauge theory (with gauge group
). Predictions from this principle agree with running
nonabelian couplings (after an extrapolation to the Planck scale using the
assumption of a ``desert'') to an accuracy of 7\%. As an explanation for the
existence of the multiple point, a speculative model using a glassy lattice
gauge theory is presented.Comment: 42, NBI-HE-93-2
Why odd-space and odd-time dimensions in even-dimesional spaces?
We are answering the question why 4-dimensional space has the metric 1+3 by
making a general argument from a certain type of equations of motion linear in
momentum for any spin (except spin zero) in any even dimension d. All known
free equations for non-zero spin for massless fields belong to this type of
equations. Requiring Hermiticity(This is a generalization of an earlier work
which shows that without assuming the Lorentz invariance -which in the present
work is assumed- the Weyl equation follows using Hermiticity.) of the equations
of motion operator as well as irreducibility with respect to the Lorentz group
representation, we prove that only metrics with the signature corresponding to
q time + (d - q) space dimensions with q being odd exist. Correspondingly, in
four dimensional space, Nature could only make the realization of 1+3
dimensional space.Comment: (only small corrections made
Trying to understand the Standard Model parameters
We stress the importance of the circa 20 parameters in the Standard Model,
which are not fixed by the model but only determined experimentally, as a
window to the physics beyond the Standard Model. However, it is a tiny window
in as far as these numbers contain only the information corresponding to about
one line of text. Looking for a method to study these coupling and mass
parameters, we put forward the idea of the Multiple Point Principle as a first
step. This principle states that Nature adjusts the coupling and mass
parameters so as to make many different vacuum states exist and have
approximately the same energy densities (cosmological constants). As an
illustrative application, we put up the proposal that a small increase (maybe
only an infinitesimal one) in the value of the top quark coupling constant
could lead to a new vacuum phase; in this new phase the binding of a bound
state of 6 top quarks and 6 anti-top quarks becomes so strong as to become a
tachyon and condense in the vacuum. Assuming the existence of a third
degenerate vacuum at the fundamental energy scale, we present a solution to the
hierarchy problem of why the ratio of the fundamental scale to the electroweak
scale is so large. We also present a 5 parameter fit to the orders of magnitude
of the quark-lepton masses and mixing angles in the Family Replicated Gauge
Group Model. In this model, the Standard Model gauge group and a gauged B-L
(baryon number minus lepton number) is extended to one set of gauge fields for
each family of fermions.Comment: Institute address corrected and one reference adde
Cosmological constant in SUGRA models with Planck scale SUSY breaking and degenerate vacua
The empirical mass of the Higgs boson suggests small to vanishing values of the quartic Higgs self-coupling and the corresponding beta function at the Planck scale, leading to degenerate vacua. This leads us to suggest that the measured value of the cosmological constant can originate from supergravity (SUGRA) models with degenerate vacua. This scenario is realised if there are at least three exactly degenerate vacua. In the first vacuum, associated with the physical one, local supersymmetry (SUSY) is broken near the Planck scale while the breakdown of the SU(2)W×U(1)Y symmetry takes place at the electroweak (EW) scale. In the second vacuum local SUSY breaking is induced by gaugino condensation at a scale which is just slightly lower than ΛQCD in the physical vacuum. Finally, in the third vacuum local SUSY and EW symmetry are broken near the Planck scale
Five adjustable parameter fit of quark and lepton masses and mixings
AbstractWe develop a model of ours fitting the quark and lepton masses and mixing angles by removing from the model a Higgs field previously introduced to organise a large atmospheric mixing angle for neutrino oscillations. Due to the off-diagonal elements dominating in the seesaw neutrino mass matrix the large atmospheric mixing angle comes essentially by itself. It turns out that we have now only five adjustable Higgs field vacuum expectation values needed to fit all the masses and mixings order of magnitudewise taking into account the renormalisation group runnings in all sectors. The CHOOZ angle comes out close to the experimental bound
The (11112) model on a 1+1 dimensional lattice
We study the chiral gauge model (11112) of four left-movers and one
right-mover with strong interactions in the 1+1 dimensional lattice. Exact
computations of relevant -matrix elements demonstrate a loophole that so
constructed model and its dynamics can possibly evade the ``no-go'' theorem of
Nielsen and Ninomiya.Comment: 15 pages, 1 fig. to appear in Phys. Rev.
Chiral symmetry restoration and axial vector renormalization for Wilson fermions
Lattice gauge theories with Wilson fermions break chiral symmetry. In the
U(1) axial vector current this manifests itself in the anomaly. On the other
hand it is generally expected that the axial vector flavour mixing current is
non-anomalous. We give a short, but strict proof of this to all orders of
perturbation theory, and show that chiral symmetry restauration implies a
unique multiplicative renormalization constant for the current. This constant
is determined entirely from an irrelevant operator in the Ward identity. The
basic ingredients going into the proof are the lattice Ward identity, charge
conjugation symmetry and the power counting theorem. We compute the
renormalization constant to one loop order. It is largely independent of the
particular lattice realization of the current.Comment: 11 pages, Latex2
A serum biomarker reflecting collagen type I degradation (C1M) is an independent risk factor for acute myocardial infarction in postmenopausal women: results from the PERF study
BioConcens: Biomass and bioenergy production agriculture – consequences for soil fertility, environment, spread of animal parasites and socio-economy
The research programme called “international research cooperation and organic integrity” was commenced for a period 2006-2010. It is coordinated by DARCOF (The Danish Research Centre for Organic Farming). The whole programme, with acronym DARCOF III, consists of 15 projects (http://www.darcof.dk/research/darcofiii/index.html). One of them is BIOCONCENS - Biomass and bioenergy production in organic farming – consequences for soil fertility, environment, spread of animal parasites and socio-economy (http://www.bioconcens.elr.dk/uk/). The production of bioenergy in organic agriculture (OA) can reduce its dependency of fossil fuels and decrease green house gasses emission; consequently it will increase sustainability of organic farms. Biorefinery concept based on co-production of biogas, bioethanol and protein fodder in organic farming will be developed within the BIOCONCENS project and the background for the project and the different work packages will be presented in this paper
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