402 citations · 2.3k across the 45 of their papers we have counts for
23 papers · 1 filter
Hyperscaling violating black holes in scalar-torsion theories
Georgios Kofinas
We study a gravity theory where a scalar field with potential, beyond its minimal coupling, is also coupled through a non-minimal derivative coupling with the torsion scalar which…
Avoidance of singularities in asymptotically safe Quantum Einstein Gravity
Georgios Kofinas, Vasilios Zarikas
New general spherically symmetric solutions have been derived with a cosmological "constant" Λas a source. This Λfield is not constant but it satisfies the properties of the asympt…
Conformal mass in Einstein-Gauss-Bonnet AdS gravity
Dileep P. Jatkar, Georgios Kofinas, Olivera Miskovic +1
In this paper, we show that the physical information given by conserved charges for asymptotically AdS spacetimes in Einstein-Gauss-Bonnet AdS gravity is encoded in the electric pa…
Conformal Mass in AdS gravity
Dileep P. Jatkar, Georgios Kofinas, Olivera Miskovic +1
We show that the Ashtekar-Magnon-Das (AMD) mass and other conserved quantities are equivalent to the Kounterterm charges in the asymptotically AdS spacetimes that satisfy the Einst…
Self-gravitating branes again
Georgios Kofinas, Maria Irakleidou
We raise on theoretical grounds the question of the physical relevance of Israel matching conditions and their generalizations to higher codimensions, the standard cornerstone of t…
A solution of the coincidence problem based on the recent galactic core black hole mass density increase
Georgios Kofinas, Vasilios Zarikas
A mechanism capable to provide a natural solution to two major cosmological problems, i.e. the cosmic acceleration and the coincidence problem, is proposed. A specific brane-bulk e…
Classical ultrarelativistic bremsstrahlung in extra dimensions
D. V. Gal'tsov, G. Kofinas, P. Spirin +1
The emitted energy and the cross-section of classical scalar bremsstrahlung in massive particle collisions in D=4+d dimensional Minkowski space M_D as well as in the brane world M_…
On Horava-Lifshitz "Black Holes"
Elias Kiritsis, Georgios Kofinas
The most general spherically symmetric solution with zero shift is found in the non-projectable Horava-Lifshitz class of theories with general coupling constants. It contains as sp…
The consistency of codimension-2 braneworlds and their cosmology
Christos Charmousis, Georgios Kofinas, Antonios Papazoglou
We study axially symmetric codimension-2 cosmology for a distributional braneworld fueled by a localised 4D perfect fluid, in a 6D Lovelock theory. We argue that only the matching…
Horava-Lifshitz Cosmology
Elias Kiritsis, Georgios Kofinas
The cosmological equations suggested by the non-relativistic renormalizable gravitational theory proposed by Hořava are considered. It is pointed out that the early universe cosmol…
Universal Kounterterms in Lovelock AdS gravity
Georgios Kofinas, Rodrigo Olea
We show the universal form of the boundary term (Kounterterm series) which regularizes the Euclidean action and background-independent definition of conserved quantities for any Lo…
Universal regularization prescription for Lovelock AdS gravity
Georgios Kofinas, Rodrigo Olea
A definite form for the boundary term that produces the finiteness of both the conserved quantities and Euclidean action for any Lovelock gravity with AdS asymptotics is presented.…
Gravitating defects of codimension-two
Georgios Kofinas, Theodore Tomaras
Thin gravitating defects with conical singularities in higher codimensions and with generalized Israel matching conditions are known to be inconsistent for generic energy-momentum.…
Vacuum energy in Einstein-Gauss-Bonnet AdS gravity
Georgios Kofinas, Rodrigo Olea
A finite action principle for Einstein-Gauss-Bonnet AdS gravity is presented. The boundary term, which is different for even and odd dimensions, is a functional of the boundary met…
Brane-bulk energy exchange : a model with the present universe as a global attractor
G. Kofinas, G. Panotopoulos, T. N. Tomaras
The role of brane-bulk energy exchange and of an induced gravity term on a single braneworld of negative tension and vanishing effective cosmological constant is studied. It is sho…
On braneworld cosmologies from six dimensions, and absence thereof
Georgios Kofinas
We consider (thin) braneworlds with conical singularities in six-dimensional Einstein-Gauss-Bonnet gravity with a bulk cosmological constant. The Gauss-Bonnet term is necessary in…
Conservation equation on braneworlds in six dimensions
Georgios Kofinas
We study braneworlds in six-dimensional Einstein-Gauss-Bonnet gravity. The Gauss-Bonnet term is crucial for the equations to be well-posed in six dimensions when non-trivial matter…
Brane cosmology with curvature corrections
G. Kofinas, R. Maartens, E. Papantonopoulos
We study the cosmology of the Randall-Sundrum brane-world where the Einstein-Hilbert action is modified by curvature correction terms: a four-dimensional scalar curvature from indu…
Black Holes on the Brane with Induced Gravity
G. Kofinas, E. Papantonopoulos, V. Zamarias
An analysis of a spherically symmetric braneworld configuration is performed when the intrinsic curvature scalar is included in the bulk action. In the case when the electric part…
Black Hole Solutions in Braneworlds with Induced Gravity
G. Kofinas, E. Papantonopoulos, V. Zamarias
We extent our previous study on spherically symmetric braneworld solutions with induced gravity, including non-local bulk effects. We find the most general static four-dimensional…
Cosmological evolution with brane-bulk energy exchange
E. Kiritsis, G. Kofinas, N. Tetradis +2
The consequences for the brane cosmological evolution of energy exchange between the brane and the bulk are analysed in detail, in the context of a non-factorizable background geom…
Spherically Symmetric Braneworld Solutions with R_{4} term in the Bulk
G. Kofinas, E. Papantonopoulos, I. Pappa
An analysis of a spherically symmetric braneworld configuration is performed when the intrinsic curvature scalar is included in the bulk action; the vanishing of the electric part…
New Perspectives on Moving Domain Walls in (A)dS_(5) Space
Georgios Kofinas
A new moving domain wall solution is obtained for a flat 3-universe. This consists of a bulk metric depending on both time and the extra coordinate, plus a dynamically interacting…