String in Horava-Lifshitz Gravity

We generalize recent analysis of the dynamics of point particle in Horava-Lifshitz background to the case of string probe when we replace the Hamiltonian constraint of the Polyakov string with the constraint that breaks Lorentz invariance of target space-time. Then we find corresponding Lagrangian and argue that the world-sheet theory is invariant under foliation preserving diffeomorphism. Finally we discuss the Hamiltonian dynamics and show that this is well defined on condition that the world-sheet lapse function obeys the projectability condition.Comment: 20 pages, references adde

Black hole solutions in Horava-Lifshitz Gravity with cubic terms

We study four dimensional non-projectable Horava-Lifshitz type gravity, in the case of an action with terms, cubic in curvature. For special choices of the free parameters of the model, we obtain two new analytic black hole solutions which exhibit the standard Schwarzschild asymptotic behavior in the large distance limit. The effect of cubic terms in the short range behavior of the black hole solutions is discussed.Comment: 25 pages, 3 figures, accepted in Phys. Rev.

Liouville-Lifshitz theory in 3+1 dimensions

We consider a four-dimensional theory in the z=3 Lifshitz context, with an exponential (Liouville) potential. We determine the exact renormalized potential of the theory and derive the non-perturbative relation between the renormalized and bare couplings. In addition, we show that Lorentz symmetry is naturally generated by quantum fluctuations in the infrared regime, and conclude that the model can be relevant to High Energy Physics

Developing and exploiting linguistic resources in research and in the didactics of Specialised Translation

This paper outlines the main state-of-the-art linguistic resources that can be developed and used in the research and in the didactics of Specialised Translation. In addition, it points to the still largely unexplored potential from the combination of Corpus Linguistics, Descriptive Translation Studies and Systemic Functional Linguistics into a single scientific and research agenda, to the benefit of both translation practitioners and trainee translators.

Viable f(T) models are practically indistinguishable from LCDM

We investigate the cosmological predictions of several $f(T)$ models, with up to two parameters, at both the background and the perturbation levels. Using current cosmological observations (geometric supernovae type Ia, cosmic microwave background and baryonic acoustic oscillation and dynamical growth data) we impose constraints on the distortion parameter, which quantifies the deviation of these models from the concordance $\Lambda$ cosmology at the background level. In addition we constrain the growth index $\gamma$ predicted in the context of these models using the latest perturbation growth data in the context of three parametrizations for $\gamma$. The evolution of the best fit effective Newton constant, which incorporates the $f(T)$-gravity effects, is also obtained along with the corresponding $1\sigma$ error regions. We show that all the viable parameter sectors of the $f(T)$ gravity models considered practically reduce these models to $\Lambda$CDM. Thus, the degrees of freedom that open up to $\Lambda$CDM in the context of $f(T)$ gravity models are not utilized by the cosmological data leading to an overall disfavor of these models.Comment: 16 pages, 9 figures, changes match published versio

Power spectra from an inflaton coupled to the Gauss-Bonnet term

We consider power-law inflation with a Gauss-Bonnet correction inspired by string theory. We analyze the stability of cosmological perturbations and obtain the allowed parameter space. We find that for GB-dominated inflation ultra-violet instabilities of either scalar or tensor perturbations show up on small scales. The Gauss-Bonnet correction with a positive (or negative) coupling may lead to a reduction (or enhancement) of the tensor-to-scalar ratio in the potential-dominated case. We place tight constraints on the model parameters by making use of the WMAP 5-year data.Comment: 5 pages, 4 figures, RevTeX, references added, published versio

Developing and exploiting linguistic resources in research and in the didactics of Specialised Translation

This paper outlines the main state-of-the-art linguistic resources that can be developed and used in the research and in the didactics of Specialised Translation. In addition, it points to the still largely unexplored potential from the combination of Corpus Linguistics, Descriptive Translation Studies and Systemic Functional Linguistics into a single scientific and research agenda, to the benefit of both translation practitioners and trainee translators.