A new numerical integration method for examining a black hole structure was realized. Black hole solutions with dilatonic hair of 4D low energy effective SuperString Theory action with GaussBonnet quadratic curvature contribution were studied, using this method, inside and outside the event horizon. Thermodynamical properties of this solution were also studied. 0260Lj, 0270Rw, 0425Dm, 0470Bw, 0470Dy

The Gauss -Bonnet invariant is one of the most promising candidates for a quadratic curvature correction to the Einstein action in expansions of supersymmetric string theory. We study the evaporation of such Schwarzschild -Gauss -Bonnet black holes which could be formed at future colliders if the Planck scale is of order a TeV, as predicted by some modern brane world models. We show that, beyond the dimensionality of space, the corresponding coupling constant could be measured by the LHC. This opens new windows for physics investigation in spite of the possible screening of microphysics due to the event horizon.PACS Numbers: 04.70.Dy (Quantum aspects of black holes), 11.25.-w (Strings and branes), 13.90.+i (phenomenology of elementary particles)

Abstract. The endpoint of black hole evaporation is a very intriguing problem of modern physics. Based on Einstein-dilaton-Gauss-Bonnet four dimensional string gravity model we show that black holes do not disappear and should become relics at the end of the evaporation process. The possibility of experimental detection of such remnant black holes is investigated. If they really exist, these objects could be a considerable part of the non baryonic dark matter in our Universe.

We test the subclasses of Horndeski gravity without Vainshtein mechanism in the strong field regime of binary pulsars. We find the rate of energy losses via the gravitational radiation predicted by such theories and compare our results with observational data from quasi-circular binaries PSR J1738+0333, PSR J0737-3039, PSR J1012+5307. In addition, we consider few specific cases: the hybrid metric-Palatini f(R)-gravity and massive Brans-Dicke theory.

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We perform analytical and numerical study of static spherically symmetric solutions in the context of Brans-Dicke-like cosmological model by Elizalde et al. [1] with an exponential potential. In this model the phantom regime arises without the appearance of any ghost degree of freedom due to the specific form of coupling. For the certain parameter ranges the model contains a regular solution which we interpret as a wormhole in an otherwise dS Universe. We put several bounds on the parameter values: ω < 0, α 2 /|ω| < 10 −5 , 22.7 φ 0 25 . The numerical solution could mimic the Schwarzschild one, so the original model is consistent with astrophysical and cosmological observational data. However differences between our solution and the Schwarzschild one can be quite large, so black hole candidate observations could probably place further limits on the φ 0 value.

We show that the non-locality recently identified in quantum gravity using resummation techniques propagates to the matter sector of the theory. We describe these non-local effects using effective field theory techniques. We derive the complete set of non-local effective operators at order N G 2 for theories involving scalar, spinor, and vector fields. We then use recent data from the Large Hadron Collider to set a bound on the scale of space-time non-locality and find M ⋆ > 3 × 10 −11 GeV.

Gauss-Bonnet gravity provides one of the most promising frameworks to study curvature corrections to the Einstein action in supersymmetric string theories, while avoiding ghosts and keeping second order field equations. Although Schwarzschild-type solutions for Gauss-Bonnet black holes have been known for long, the Kerr-Gauss-Bonnet metric is missing. In this paper, a five dimensional Gauss-Bonnet approximation is analytically derived for spinning black holes and the related thermodynamical properties are briefly outlined.