Related papers: A stringy black string and a stringy black hole in…
The Ba\~nados-Teitelboim-Zanelli (BTZ) black hole metric solves the three-dimensional Einstein's theory with a negative cosmological constant as well as all the generic higher derivative gravity theories based on the metric; as such it is a…
We study two classes of static uniform black string solutions in a (4+1)-dimensional SU(2) Einstein-Yang-Mills model. These configurations possess a regular event horizon and corresponds in a 4-dimensional picture to axially symmetric black…
The three-dimensional static and circularly symmetric solution of the Einstein-Born-Infeld-dilaton system is derived. The solutions corresponding to low energy string theory are investigated in detail, which include black hole solutions if…
The last three years have again seen new exciting developments in the area of higher dimensional black objects. For black objects with noncompact higher dimensions, the solution space was exlored further within the blackfold approach and…
In this paper, by means of regularisation procedure via $r\to \sqrt{r^2+l_0^2}$ (where $l_0$ can play the role of zero point length), we first modify the gravitational and electromagnetic potentials in two dimensions and then we solve the…
We generalize the entropy function formalism to five-dimensional and four-dimensional non-extremal black holes in string theory. In the near horizon limit, these black holes have BTZ metric as part of the spacetime geometry. It is shown…
We construct analytical solutions describing black holes and black strings in the Einstein $SU(N)$-non-linear sigma model in $(3+1)$ dimensions. This construction is carried out using the maximal embbeding ansatz of $SU(2)$ together with…
We discuss properties of black holes which are pierced by special configurations of cosmic strings. For static black holes we consider radial strings in the limit when the number of strings grows to infinity while the tension of each single…
We present a new class of spinning black hole solutions in $(2+1)$-dimensional general relativity minimally coupled to a dilaton with potential $e^{b\phi}\Lambda$. When $b=4$, the corresponding spinning black hole is a solution of low…
A C-metric type solution for general relativity with cosmological constant is presented in 2+1 dimensions. It is interpreted as a three-dimensional black hole accelerated by a strut. Positive values of the cosmological constant are…
We obtain cosmological four dimensional solutions of the low energy effective string theory by reducing a five dimensional black hole, and black hole--de Sitter solution of Einstein gravity down to four dimensions. The appearance of a…
Computations in general relativity have revealed an interesting phase diagram for the black hole - black string phase transition, with three different black objects present for a range of mass values. We can add charges to this system by…
As argued in arXiv:2104.10172, introducing a non-minimally coupled scalar field, three-dimensional Einstein gravity can be extended by infinite families of theories which admit simple analytic generalizations of the charged BTZ black hole.…
We investigate string or branelike solutions for four-dimensional vacuum Einstein equations in the presence of cosmological constant. For the case of negative cosmological constant, the Banados-Teitelboim-Zanelli black string is the only…
Generalizations of the Black Hole geometry of Ba\~nados, Teitelboim and Zanelli (BTZ) are presented. The theory is three-dimensional vacuum Einstein theory with a negative cosmological constant. The $n$-black-hole solution has $n$…
In this paper, we obtain two different static black string solutions by considering as sources axisymmetric dark matter distributions in 3+1 dimensions. These solutions tend asymptotically to the usual static and uncharged black string…
We obtain cosmological four dimensional solutions of the low energy effective string theory by reducing a five dimensional black hole, and black hole--de Sitter solution of the Einstein gravity down to four dimensions. The appearance of a…
We report the existence of unstable, s-wave modes, for black strings in Gauss-Bonnet theory (which is quadratic in the curvature) in seven dimensions. This theory admits analytic uniform black strings that in the transverse section are…
When two point particles, coupled to three dimensional gravity with a negative cosmological constant, approach each other with a sufficiently large center of mass energy, then a BTZ black hole is created. An explicit solution to the…
In the first part of this talk, I consider some exact string solutions in curved spacetimes. In curved spacetimes with a Killing vector (timelike or spacelike), the string equations of motion and constraints are reduced to the Hamilton…