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Full-Text Articles in Physics
A Proposal On Culling & Filtering A Coxeter Group For 4d, N = 1 Spacetime Susy Representations: Revised, D. E. A. Gates, S. James Gates, Kory Stiffler
A Proposal On Culling & Filtering A Coxeter Group For 4d, N = 1 Spacetime Susy Representations: Revised, D. E. A. Gates, S. James Gates, Kory Stiffler
Dartmouth Scholarship
We present an expanded and detailed discussion of the mathematical tools required to cull and filter representations of the Coxeter Group BC 4 into providing bases for the construction of minimal off-shell representations of the 4D, N" role="presentation" style="box-sizing: border-box; display: inline-table; line-height: normal; letter-spacing: normal; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">NN = 1 spacetime supersymmetry algebra.
Gravitational Origin Of The Weak Interaction's Chirality, Stephon Alexander, Antonino Marcianò, Lee Smolin
Gravitational Origin Of The Weak Interaction's Chirality, Stephon Alexander, Antonino Marcianò, Lee Smolin
Dartmouth Scholarship
We present a new unification of the electro-weak and gravitational interactions based on the joining the weak SU(2) gauge fields with the left handed part of the space- time connection, into a single gauge field valued in the complexification of the local Lorentz group. Hence, the weak interactions emerge as the right handed chiral half of the space-time connection, which explains the chirality of the weak interaction. This is possible, because, as shown by Plebanski, Ashtekar, and others, the other chiral half of the space-time connection is enough to code the dynamics of the gravitational degrees of freedom. This unification …
Inflation In (Super-)Renormalizable Gravity, Fabio Briscese, Antonino Marcianò, Leonardo Modesto, Emmanuel N. Saridakis
Inflation In (Super-)Renormalizable Gravity, Fabio Briscese, Antonino Marcianò, Leonardo Modesto, Emmanuel N. Saridakis
Dartmouth Scholarship
We investigate a (super-)renormalizable and ghost-free theory of gravity, showing that under a natural (exponential) ansatz of the form factor and a suitable truncation it can give rise to the Starobinsky inflationary theory in cosmological frameworks, and thus offering a theoretical justification of its origin. We study the corresponding inflationary evolution and we examine the generation of curvature perturbations, adapting the f(R)-like equations in a symmetry-reduced FLRW metric. Furthermore, we analyze how the ultraviolet regime of a simply renormalizable and unitary theory of gravity is also compatible with the Starobinsky action, and hence we show that such a theory could …
Gauge Field Preheating At The End Of Inflation, J. Tate Deskins, John T. Giblin Jr., Robert R. Caldwell
Gauge Field Preheating At The End Of Inflation, J. Tate Deskins, John T. Giblin Jr., Robert R. Caldwell
Dartmouth Scholarship
Here we consider the possibility of preheating the Universe via the parametric amplification of a massless, U(1) abelian gauge field. We assume that the gauge field is coupled to the inflaton via a conformal factor with one free parameter. We present the results of high-resolution three-dimensional simulations of this model and show this mechanism efficiently preheats the Universe to a radiation-dominated final state.
Information Content Of Spontaneous Symmetry Breaking, Marcelo Gleiser, Nikitas Stamatopoulos
Information Content Of Spontaneous Symmetry Breaking, Marcelo Gleiser, Nikitas Stamatopoulos
Dartmouth Scholarship
We propose a measure of order in the context of nonequilibrium field theory and argue that this measure, which we call relative configurational entropy (RCE), may be used to quantify the emergence of coherent low-entropy configurations, such as time-dependent or time-independent topological and nontopological spatially extended structures. As an illustration, we investigate the nonequilibrium dynamics of spontaneous symmetry breaking in three spatial dimensions. In particular, we focus on a model where a real scalar field, prepared initially in a symmetric thermal state, is quenched to a broken-symmetric state. For a certain range of initial temperatures, spatially localized, long-lived structures known …
Deformed Lorentz Symmetry And Relative Locality In A Curved/Expanding Spacetime, Giovanni Amelino-Camelia, Antonino Marcianò, Marco Matassa, Giacomo Rosati
Deformed Lorentz Symmetry And Relative Locality In A Curved/Expanding Spacetime, Giovanni Amelino-Camelia, Antonino Marcianò, Marco Matassa, Giacomo Rosati
Dartmouth Scholarship
The interest of part of the quantum-gravity community in the possibility of Planck-scale-deformed Lorentz symmetry is also fueled by the opportunities for testing the relevant scenarios with analyses, from a signal-propagation perspective, of observations of bursts of particles from cosmological distances. In this respect the fact that so far the implications of deformed Lorentz symmetry have been investigated only for flat (Minkowskian) spacetimes represents a very significant limitation, since for propagation over cosmological distances the curvature/expansion of spacetime is evidently tangible. We here provide a significant step toward filling this gap by exhibiting an explicit example of Planck-scale-deformed relativistic symmetries …
Casimir Forces And Non-Newtonian Gravitation, Roberto Onofrio
Casimir Forces And Non-Newtonian Gravitation, Roberto Onofrio
Dartmouth Scholarship
The search for non-relativistic deviations from Newtonian gravitation can lead to new phenomena signalling the unification of gravity with the other fundamental interactions. Various recent theoretical frameworks indicate a possible window for non-Newtonian forces with gravitational coupling strength in the micrometre range. The major expected background in the same range is attributable to the Casimir force or variants of it if dielectric materials, rather than conducting ones, are considered. Here we review the measurements of the Casimir force performed so far in the micrometre range and how they determine constraints on non-Newtonian gravitation, also discussing the dominant sources of false …
Affinity For Scalar Fields To Dissipate, Arjun Berera, Rudnei O. Ramos
Affinity For Scalar Fields To Dissipate, Arjun Berera, Rudnei O. Ramos
Dartmouth Scholarship
The zero-temperature effective equation of motion is derived for a scalar field interacting with other fields. For a broad range of cases, involving interaction with as few as one or two fields, dissipative regimes are found for the scalar field system. The zero-temperature limit constitutes a baseline effect that will be prevalent in any general statistical state. Thus, the results found here provide strong evidence that dissipation is the norm not the exception for an interacting scalar field system. For application to inflationary cosmology, this provides convincing evidence that warm inflation could be a natural dynamics once proper treatment of …
Inhomogeneous Nucleation In A Quark-Hadron Pphase Transition, P. Shukla, A. K. Mohanty, S. K. Gupta, Marcelo Gleiser
Inhomogeneous Nucleation In A Quark-Hadron Pphase Transition, P. Shukla, A. K. Mohanty, S. K. Gupta, Marcelo Gleiser
Dartmouth Scholarship
The effect of subcritical hadron bubbles on a first-order quark-hadron phase transition is studied. These subcritical hadron bubbles are created due to thermal fluctuations, and can introduce a finite amount of phase mixing (quark phase mixed with hadron phase) even at and above the critical temperature. For reasonable choices of surface tension and correlation length, as obtained from the lattice QCD calculations, we show that the amount of phase mixing at the critical temperature remains below the percolation threshold. Thus, as the system cools below the critical temperature, the transition proceeds through the nucleation of critical-size hadron bubbles from a …