Related papers: Large-scale messengers from arbitrary spin fields
The quantum theory of a harmonic oscillator with a time dependent frequency arises in several important physical problems, especially in the study of quantum field theory in an external background. While the mathematics of this system is…
We conjecture that the time-reversal-even component of the pair production rate $\Gamma$ of particles in background fields in conformal 3+1 dimensional field theories is given by the anomalous trace $\langle T^\mu_{\ \mu}\rangle$ of the…
Nontrivial translation matrices occur for spin (A,B)+(C,D) with |A-C| = |B-D| = 1/2, necessarily associating a (C,D) field with a spin (A,B) field. Including translation matrices in covariant non-unitary Poincare representations also…
Free massive higher spin fields in weak background gravitational fields are discussed. Contrary to the spin one case, higher spin fields should have nontrivial non-minimal couplings to the curvature. A precise analysis is given for the spin…
A `covariant' field that transforms like a relativistic field operator is required to be a linear combination of `canonical' fields that transform like annihilation and creation operators and with invariant coefficients. The Invariant…
We offer a clear physical explanation for the emergence of the quantum operator formalism, by revisiting the role of the vacuum field in quantum mechanics. The vacuum or random zero-point radiation field has been shown previously, using the…
We suggest a new mechanism for generation of large-scale magnetic field in the hot plasma of early universe which is based on the parity violation in weak interactions and depends neither on helicity of matter turbulence resulting in the…
The covariant description of massless particles of arbitrary spin typically employs symmetric tensors of rank $s$ and rests on a local symmetry carried by symmetric tensor parameters of rank $s-1$, suitably generalizing the $U(1)$…
We consider the resonant production of fermions from an oscillating axial background. The classical evolution of the axial field is given by that of a massive pseudovector field, as suggested by the renormalizability of the theory. We look…
It has been shown that the massless irreducible representations of the Poincar\'e group with continuous spin can be obtained from a classical point particle action which admits a generalization to a conformally invariant string action. The…
The vacuum state in quantum field theory is known to exhibit an important number of fundamental physical features. In this work we explore the possibility that this state could also present a non-trivial space-time structure on large…
Starting from certain causality conditions and a discrete form of general covariance, we derive a very general family of classically stochastic, sequential growth dynamics for causal sets. The resulting theories provide a relatively…
It has been shown in literature that a possible mechanism of mass generation for gauge fields is through a topological coupling of vector and tensor fields. After integrating over the tensor degrees of freedom, one arrives at an effective…
Particle creation by strong and time-varying backgrounds is a robust prediction of quantum field theory. Another well-established feature of field theory is that classical symmetries do not always extend to the quantized theory. When this…
We present universal formulas for particle production from gravitational inhomogeneities. In the massless limit the result is strikingly simple and completely determined by the two-point function of the energy-momentum tensor that is fixed…
We give a broad overview of a construction of a theory for matter on fixed causal set backgrounds. We introduce the Sorkin-Johnston formalism for a free (real) scalar field theory that is applicable to regions of continuum spacetimes as…
We construct relativistic-invariant spinning-particle Lagrangian without auxiliary variables. Spin is considered as a composed quantity constructed on the base of non-Grassmann vector-like variable. The variational problem guarantees both…
We study the generation of magnetic fields during the stage of particle production resulting from spinodal instabilities during phase transitions out of equilibrium. The main premise is that long-wavelength instabilities that drive the…
We investigate the propagation of electromagnetic fields and potentials in the plasma of the early Universe, assuming a Friedmann-Robertson-Walker background with negative curvature. Taking over results from classical plasma physics, we…
A light scalar degree of freedom, as the one possibly responsible for the accelerated expansion of the Universe, could leave observable traces in the inspiral gravitational wave signal of binary systems. In order to study these effects, we…