arXiv subjects
Publications and source records attributed to Ricardo Gallego Torromé.
We argue that in a framework for emergent quantum mechanics, the weak equivalence principle is a consequence of concentration of measure in large dimensional spaces of $1$-Lipshitz functions. Furthermore, as a consequence of the emergent framework and the properties that we assume for the fundamental dynamics, it is argued that gravity must be a classical, emergent interaction.
A geometric framework for metrics of maximal acceleration which is applicable to large proper accelerations is discussed, including a theory of connections associated with the geometry of maximal acceleration. In such a framework it is shown that the uniform bound on the proper maximal acceleration implies an uniform bound for certain bilinear combinations of the Riemannian curvature components in the domain of the spacetime where curvature is finite.
In this paper we consider classical electrodynamic theories with maximal acceleration and some of their phenomenological consequences for laser-plasma acceleration. It is shown that in a recently proposed higher order jet theory of electrodynamics, the maximal effective acceleration reachable by a consistent bunch of point charged particles being accelerated by the wakefield is damped for bunches containing large number of charged particles. We argue that such prediction of the theory is falsifiable. In the case of Born-Infeld kinematics, laser-plasma acceleration phenomenology provides an upper bound for the Born-Infeld parameter $b$. Improvements in the beam qualities will imply stronger constraints on $b$.
Let $M$ be a smooth manifold and $\mathcal{S}$ a semi-spray defined on a sub-bundle $\mathcal{C}$ of the tangent bundle $TM$. In this work it is proved that the only non-trivial $k$-jet approximation to the exact geodesic deviation equation of $\mathcal{S}$, linear on the deviation functions and invariant under an specific class of local coordinate transformations is the Jacobi equation. However, if the linearity property on the dependence in the deviation functions is not imposed, then there are differential equations whose solutions admit $k$-jet approximations and are invariant under arbitrary coordinate transformations. As an example of higher order geodesic deviation equations we study the first and second order geodesic deviation equations for a Finsler spray.
Maximal accelerations are related to the existence of a minimal time for a given physical system. Such a minimal time can be either an intrinsic time scale of the system or connected to a quantum gravity induced ultraviolet cut off. In this paper we pedagogically introduce the four major formulations for kinematics accounting for a maximal acceleration. Some phenomenological repercussion are offered as hints for future investigations.
General relativity is incomplete because it cannot describe quantum effects of space-time. The complete theory of quantum gravity is not yet known and to date no observational evidence exists that space-time is quantized. However, in most approaches to quantum gravity the space-time manifold of general relativity is only an effective limit that, among other things like higher curvature terms, should receive corrections stemming from space-time defects. We here develop a modification of general relativity that describes local space-time defects and solve the Friedmann equations. From this, we obtain the time-dependence of the density of defects. It turns out that the defects' density dilutes quickly, somewhat faster even than radiation.
A geometric interpretation for quantum correlations and entanglement according to a particular framework of emergent quantum mechanics is developed. The mechanism described is based on two ingredients: 1. At an hypothetical sub-quantum level description of physical systems, the dynamics has a regime where it is partially ergodic and 2. A formal projection from a two-dimensional time mathematical formalism of the emergent quantum theory to the usual one-dimensional time formalism of quantum dynamics. Observable consequences of the theory are obtained. Among them we show that quantum correlations must be instantaneous from the point of view of the spacetime description, but the spatial distance up to which they can be observed must be bounded. It is argued how our mechanism avoids Bell theorem and Kochen-Specken theorem. Evidence for non-signaling faster than the speed of light in our proposal is discussed.
Given a Finsler space (M,F) on a manifold M, the averaging method associates to Finslerian geometric objects affine geometric objects} living on $M$. In particular, a Riemannian metric is associated to the fundamental tensor $g$ and an affine, torsion free connection is associated to the Chern-Rund connection. As an illustration of the technique, a generalization of the Gauss-Bonnet theorem to Berwald surfaces using the average metric is presented. The parallel transport and curvature endomorphisms of the average connection are obtained. The holonomy group for a Berwald space is discussed. New affine, local isometric invariants of the original Finsler metric. The heredity of the property of symmetric space from the Finsler space to the average Riemannian metric is proved.
The notion of singular generalized Finsler spacetime and singular generalized Berwald spacetime are introduced and their relevance for the description of classical gravity discussed. A method to construct examples of such generalized Berwald spacetimes is sketched. The method is applied at two different levels of generality. First, a class of flat, singular generalized Berwald spacetimes is obtained. Then in an attempt of further generalization, a class of non-flat generalized Berwald spacetimes is presented and the associated Einstein field equations are discussed. In this context, an argument in favour of a small value of the cosmological constant is given. The physical significance of the models is briefly discussed in the last section.
A model for the dynamics of a classical point charged particle interacting with higher order jet fields is introduced. In this model, the dynamics of the charged particle is described by an implicit ordinary second order differential equation. Such equation is free of run-away and pre-accelerated solutions of Dirac's type. The theory is Lorentz invariant, compatible with the first law of Newton and Larmor's power radiation formula. Few implications of the new equation in the phenomenology of non-neutral plasmas is considered.
A geometric theory for spacetimes whose world lines associated with physical particles have an upper bound for the proper acceleration is developed. After some fundamental remarks on the requirements that the classical dynamics for point particles should hold, the notion of generalized metric and a theory of maximal proper acceleration are introduced. A perturbative approach to metrics of maximal proper acceleration is discussed and we show how it provides a consistent theory where the associated Lorentzian metric corresponds to the limit when the maximal proper acceleration goes to infinity. Then several of the physical and kinematical properties of the maximal acceleration metric are investigated, including a discussion of the rudiments of the causal theory and the introduction of the notions of radar distance and celerity function. We discuss the corresponding modification of the Einstein mass-energy relation when the associated Lorentzian geometry is flat. In such context it is also proved that the physical dispersion relation is relativistic. Two possible physical scenarios where the modified mass-energy relation could be confronted against experiment are briefly discussed.
In a recent paper (arXiv:1412.6000) a general mechanism for emergence of cosmological space-time geometry from a quantum gravity setting was devised and departure from standard dispersion relations for elementary particle were predicted. We elaborate here on this approach extending the results obtained in that paper and showing that generically such a framework will not lead to higher order modified dispersion relations in the matter sector. Furthermore, we shall discuss possible phenomenological constraints to this scenarios showing that space-time will have to be by nowadays classical to a very high degree in order to be consistent with current observations.
Models for deterministic quantum mechanics of Cartan-Randers type are introduced, together with the fundamental notions of the concentration of measure theory. We explain how the application of the concentration of measure to Cartan-Randers models provides a framework from which it emerge 1. The invariance under infinitesimal diffeomorphisms of the macroscopic dynamics 2. A mechanism for reduction of the quantum state and 3. The Weak Equivalence Principle.
The action of parity inversion, time inversion and charge conjugation operations on several differential equations for a classical point charged particle are described. Moreover, we consider the notion of {\it symmetrized acceleration} $Δ_q$ that for models of point charged electrodynamics is sensitive to deviations from the standard Lorentz force equation. It is shown that $Δ_q$ can be observed with current or near future technology and that it is an useful quantity for probing radiation reaction models. To illustrate these points we consider four different models for the dynamics of point charged particles and radiation reaction.
Using an extension to isometries of the associated Sasaki structure, we establish a Lie transformation group structure for the set of isometries of a pseudo-Finsler conical metric.
We consider specific deterministic quantum models of Cartan-Randers type and show how a dualized abelian gauge symmetry, diffeomorphism invariance, the Principle of Inertia, reversibility of phenomenological dynamics, maximal acceleration and maximal propagation speed for matter arise from such models in an phenomenological description. Two particular predictions are highlighted: the first is the value of maximal acceleration is universal and has the value of order 10^{52} m/s^2. The second prediction is that gauge symmetries in phenomenological models must come dualized and containing an abelian sector.
Motivated by obtaining a consistent mathematical description for the radiation reaction of point charged particles in linear classical electrodynamics, a theory of generalized higher order tensors and differential forms is introduced. The generalization of some fundamental notions of the differential geometry and the theory of differential forms is presented. In particular, the cohomology and integration theories for generalized higher order forms are developed, including the Cartan calculus, a generalization of de Rham cohomology and a version of Thom's isomorphism theorem. We consider in detail a special type of generalized higher order tensors associated with bounded maximal $n$-acceleration and use it as a model of spacetime. A generalization of electrodynamic theory with higher order fields is introduced. We show that combining the generalized higher order fields with maximal acceleration geometry the evolution of a point charged particle interacting with the generalized higher order fields can be described by solutions of an implicit second order ordinary differential equation. In flat space such equation is Lorentz invariant, does not have pre-accelerated solutions of Dirac's type or run-away solutions, it is compatible with Newton's first law of dynamics and with the covariant Larmor's power radiation law. A generalization of the Maxwell-Lorentz theory is also introduced. The theory is linear in the field sector and it reduces to the standard Maxwell-Lorentz electrodynamics when the maximal acceleration is infinite. Finally, we discuss the assumptions of our framework in addition to some predictions of the theory.
As a natural application of the {\it theory of geometric averaging} in Finsler geometry and generalized Finsler geometry, a new approach to investigate {\it generalized Finsler geometry}, based on a convex invariance of the average structures, is introduced.