103,520 research outputs found
Associated scalar-vector production at the LHC within an effective Lagrangian approach
We consider the case in which a strong dynamics is responsible for
Electro-Weak Symmetry Breaking (EWSB) and both a scalar and a vector ,
respectively a singlet and a triplet under a custodial , are
relevant and have a mass below the cut-off . In this
framework we study the total cross sections for the associated production
at the LHC at 14 TeV as functions of two independent free parameters.Comment: To appear in the Proceedings of IFAE2010 - Incontri di Fisica delle
Alte Energie, Rome, Italy, 7-9 April 201
Schrodinger representation for the polarized Gowdy model
The polarized Gowdy model is, in a standard gauge, characterized
by a point particle degree of freedom and a scalar field degree of freedom
obeying a linear field equation on . The Fock
representation of the scalar field has been well-studied. Here we construct the
Schrodinger representation for the scalar field at a fixed value of the Gowdy
time in terms of square-integrable functions on a space of distributional
fields with a Gaussian probability measure. We show that ``typical'' field
configurations are slightly more singular than square-integrable functions on
the circle. For each time the corresponding Schrodinger representation is
unitarily equivalent to the Fock representation, and hence all the Schrodinger
representations are equivalent. However, the failure of unitary
implementability of time evolution in this model manifests itself in the mutual
singularity of the Gaussian measures at different times.Comment: 13 page
The Problems of Time and Observables: Some Recent Mathematical Results
We present 2 recent results on the problems of time and observables in
canonical gravity. (1) We cannot use parametrized field theory to solve the
problem of time because, strictly speaking, general relativity is not a
parametrized field theory. (2) We show that there are essentially no local
observables for vacuum spacetimes.Comment: Talk presented at the Lanczos Centenary Conference 3 pages, plain Te
A Deformation Theory of Self-Dual Einstein Spaces
The self-dual Einstein equations on a compact Riemannian 4-manifold can be
expressed as a quadratic condition on the curvature of an (spin)
connection which is a covariant generalization of the self-dual Yang-Mills
equations. Local properties of the moduli space of self-dual Einstein
connections are described in the context of an elliptic complex which arises in
the linearization of the quadratic equations on the curvature. In
particular, it is shown that the moduli space is discrete when the cosmological
constant is positive; when the cosmological constant is negative the moduli
space can be a manifold the dimension of which is controlled by the
Atiyah-Singer index theorem.Comment: 13 page
Covariant Phase Space Formulation of Parametrized Field Theories
Parametrized field theories, which are generally covariant versions of
ordinary field theories, are studied from the point of view of the covariant
phase space: the space of solutions of the field equations equipped with a
canonical (pre)symplectic structure. Motivated by issues arising in general
relativity, we focus on: phase space representations of the spacetime
diffeomorphism group, construction of observables, and the relationship between
the canonical and covariant phase spaces.Comment: 22 page
Natural Symmetries of the Yang-Mills Equations
We define a natural generalized symmetry of the Yang-Mills equations as an
infinitesimal transformation of the Yang-Mills field, built in a local, gauge
invariant, and Poincar\'e invariant fashion from the Yang-Mills field strength
and its derivatives to any order, which maps solutions of the field equations
to other solutions. On the jet bundle of Yang-Mills connections we introduce a
spinorial coordinate system that is adapted to the solution subspace defined by
the Yang-Mills equations. In terms of this coordinate system the complete
classification of natural symmetries is carried out in a straightforward
manner. We find that all natural symmetries of the Yang-Mills equations stem
from the gauge transformations admitted by the equations.Comment: 23 pages, plain Te
Socially Optimal Criminal Justice System Waiting Times: A More General Theoretical Analysis
Criminal justice system delay, which is defined as the time elapsing between the defendant being charged and the case being listed at court, has up to some point, socially valuable flexibility value. This insight borrowed from the options literature in finance, makes it potentially possible to formally model and estimate socially optimal criminal justice system waiting times. This exercise is attempted in this paper by randomising the defendant’s probability of conviction, which is a critical argument in the defendant’s expected cost of going to trial and the monetary value of a conviction to society .The probability of conviction is assumed to conform to a uniform probability distribution with increasing variability until the trial date. What drives this variability is a continuous stream of information impacting on the defendant’s probability of conviction, which is continuously evaluated by the defendant and prosecutor as they formulate their different strategies given their respective conflicting objectives. Endogenising the probability of conviction in this way enables the respective payoffs of the defendant and prosecutor to be expressed as dynamic net present values per unit of time. The economic value of this flexibility to wait is measured as the rate of change in the sum of these dynamic NPVs per unit of time. Socially optimal delay is defined as the trial wait, which maximises the dollar value of the sum of the economic value of flexibility to the prosecutor (society) and the defendant simultaneously, and is the optimal time to list the case at the court. The corresponding dollar value is the total marginal social value of delay. Corresponding to the socially optimal wait and the total marginal social value of delay will be the optimal sentence discount for the prosecutor (society) to offer the defendant and the defendant’s optimal plea. Society makes a trade off between two conflicting objectives, the need to ensure justice to the defendant as legally and morally defined with the need to resolve the issue as quickly as possible.
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