Related papers: Self-interacting scalar fields at high-temperature
We analyse the high temperature behaviour of softly broken supersymmetric theories taking into account the role played by effective non-renormalizable terms generated by the decoupling of superheavy degrees of freedom or the Planck scale…
We investigate scalar-tensor theories, motivated by dark energy models, in the strong gravity regime around the black hole at the centre of our galaxy. In such theories general relativity is modified since the scalar field couples to…
Since an acceptable dark matter candidate may interact only weakly with ordinary matter and radiation, it is of interest to consider the limiting case where the dark matter interacts only with gravity and itself, the matter originating by…
Cosmological models describing the non-gravitational interaction between dark matter and dark energy are based on some phenomenological choices of the interaction rates between dark matter and dark energy. There is no such guiding rule to…
Using transfer-matrix method a correspondence between $2D$ classical spin systems ($2D$ Ising model and six-vertex model) and $1D$ quantum spin systems is considered. We find the transfer matrix in two limits - in a well-known…
We demonstrate that self-interacting dark matter models with interactions mediated by light particles can have significant deviations in the matter power-spectrum and detailed structure of galactic halos when compared to a standard cold…
For heavy quarkonia of moderate energy, we generalize the relevant successful theory, non-relativistic Quantum Chromodynamics (NRQCD), to include interactions in nuclear matter. The new resulting theory, NRQCD with Glauber gluons, provides…
In a ghost-condensate model of dark energy the combined dynamics of the scalar field and gravitation is shown to impose non-trivial restriction on the self-interaction of the scalar field. Using this restriction we show that the choice of a…
Since the initial investigation by Matsui and Satz heavy quark bound states at finite temperature have been subject to numerous studies. The derivation of a finite-temperature potential from first principles was attempted only recently…
We study a self-interacting scalar field theory in the presence of a \delta-function background potential. The role of surface interactions in obtaining a renormalizable theory is stressed and demonstrated by a two-loop calculation. The…
We investigate the high-energy properties of matter theories coupled to quantum gravity. Specifically, we show that quantum gravity fluctuations generically induce matter self-interactions in a scalar theory. Our calculations apply within…
We present a scenario where a $Z_2$-symmetric scalar field $\phi$ first drives cosmic inflation, then reheats the Universe but remains out-of-equilibrium itself, and finally comprises the observed dark matter abundance, produced by particle…
It may prove useful in cosmology to understand the behavior of the energy distribution in a scalar field that interacts only with gravity and with itself by a pure quartic potential, because if such a field existed it would be…
This thesis includes several original results. All of them are already published or submitted for publication. I present here the short summary of main results: The ultraviolet singular structure of the bulk-to-bulk propagators for higher…
We study the relational cosmological dynamics emerging from interacting group field theory (GFT) models minimally coupled to a massless clock scalar field and a self-interacting scalar field. We focus on two broad classes of GFT…
We review the difficulties of the generalized Chaplygin gas model to fit observational data, due to the tension between background and perturbative tests. We argue that such issues may be circumvented by means of a self-interacting scalar…
In this work, we study interaction between dark energy and dark matter, where dark energy is described by a massive vector field, and dark matter is modelled as a fluid. We present a new interaction term, which affects only perturbations…
On the basis of a new method to derive the effective action the nonperturbative concept of "dynamical generation" is explained. A non-trivial, non-Hermitian and PT-symmetric solution for Wightman's scalar field theory in four dimensions is…
If dark matter has strong self-interactions, future astrophysical and cosmological observations, together with a clearer understanding of baryonic feedback effects, might be used to extract the velocity dependence of the dark matter…
We investigate the interaction between dark energy and dark matter in the framework of irreversible thermodynamics of open systems with matter creation/annihilation. We consider dark energy and dark matter as an interacting two component…