scholarly journals DENOUEMENT OF A WORMHOLE–BRANE ENCOUNTER

2009 ◽  
Vol 18 (12) ◽  
pp. 1809-1819
Author(s):  
ENRICO RODRIGO
Keyword(s):  
Black Holes ◽  
Dark Matter ◽  
Brane World ◽  
Dark Matter Candidate ◽  
Brane Worlds ◽  
Higher Dimensional ◽  
The Creation ◽  
World Ethos ◽  
Baby Universe

Higher-dimensional black holes have long been considered within the context of brane worlds. Recently, it was shown that the brane-world ethos also permits the consideration of higher-dimensional wormholes. When such a wormhole, pre-existing in the bulk, impinges upon our universe, taken to be a positive-tension three-brane, it can induce the creation in our universe of a wormhole of ordinary dimensionality. The throat of this wormhole might fully constrict, pinch off, and thus birth a baby universe. Alternatively, the induced wormhole might persist. I show that persistence is more likely and note that the persistent wormhole manifests itself as a particle-like object whose interaction with cosmic matter is purely gravitational. I consider the viability of this object as a dark matter candidate.

scholarly journals ROTATING BLACK HOLES IN HIGHER DIMENSIONAL BRANE WORLDS

2006 ◽  
Vol 15 (02) ◽  
pp. 171-188 ◽  
Author(s):  
GAUTAM SENGUPTA
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Causal Structure ◽  
Brane World ◽  
Black String ◽  
Brane Worlds ◽  
Rotating Black Hole ◽  
Geodesic Equations ◽  
Higher Dimensional ◽  
Rotating Black Holes

A black string generalization of the Myers–Perry N-dimensional rotating black hole is considered in an (N + 1)-dimensional Randall–Sundrum brane world. The black string intercepts the (N - 1) brane in a N-dimensional rotating black hole. We examine the diverse cases arising for various non-zero rotation components and obtain the geodesic equations for these space–times. The causal structure and asymptotics of the resulting brane world geometries are analyzed.

scholarly journals A constraint on light primordial black holes from the interstellar medium temperature

2021 ◽  
Author(s):  
Hyungjin Kim
Keyword(s):  
Black Holes ◽  
Dark Matter ◽  
Dwarf Galaxy ◽  
Dark Matter Candidate ◽  
Primordial Black Hole ◽  
Primordial Black Holes ◽  
Substantial Fraction ◽  
Interstellar Gas ◽  
Medium Temperature ◽  
Fast Electrons

Abstract Primordial black holes are a viable dark matter candidate. They decay via Hawking evaporation. Energetic particles from the Hawking radiation interact with interstellar gas, depositing their energy as heat and ionization. For a sufficiently high Hawking temperature, fast electrons produced by black holes deposit a substantial fraction of energy as heat through the Coulomb interaction. Using the dwarf galaxy Leo T, we place an upper bound on the fraction of primordial black hole dark matter. For M < 5 × 10−17M⊙, our bound is competitive with or stronger than other bounds.

scholarly journals Pendidikan Ilmu Astronomi Dari Historis Sampai Heliosentris

2018 ◽  
Vol 2 (2) ◽  
pp. 93-110
Author(s):  
Nabil Nabil
Keyword(s):  
Black Holes ◽  
Dark Matter ◽  
Dark Energy ◽  
Human Life ◽  
History Of Astronomy ◽  
The West ◽  
History Of ◽  
The Creation ◽  
The Universe ◽  
Origin Of The Universe

Science in human life is very important to illuminate every walk of life, both physical (material) and metaphysical (immaterial). The universe was born millions and even billions of years ago, so many astronomical physicists calculate the origin of the universe, so the creation of the theory of bigbang, black holes, dark energy, dark matter, newton gravity, etc. Astronomy is important in teaching to know the phenomena of the universe (general), and to know times of worship (specifically). Before entering the science, it is better to know the history of astronomy, both the history of theory, and the figures then the hierarchy between geocentric and heliocentric in several views, both from the view of a character, as well as the view of the scriptures. Indeed, when humans think about the universe, in this case about the center of the universe there will be a hierarchy with the scriptures. This is a matter between different reason and revelation. Therefore, in this paper I touch on the issue of Heliocentric and Geocentric. And do not forget the astronomical figures from the West and East.

scholarly journals Brane cosmology and the self-tuning of the cosmological constant in the presence of bulk black holes

2020 ◽  
Vol 80 (7) ◽  
Author(s):  
P. Betzios ◽  
O. Papadoulaki
Keyword(s):  
Black Hole ◽  
Cosmological Constant ◽  
Static Solution ◽  
Brane World ◽  
De Sitter ◽  
Brane Cosmology ◽  
Brane Worlds ◽  
Higher Dimensional ◽  
Self Tuning ◽  
Hole Geometry

Abstract Motivated by the holographic self-tuning proposal of the cosmological constant, we generalize and study the cosmology of brane-worlds embedded in a higher-dimensional bulk black hole geometry. We describe the equations and matching conditions in the case of flat, spherical and hyperbolic slicing of the bulk geometry and find the conditions for the existence of a static solution. We solve the equations that govern dynamical geometries in the probe brane limit and we describe in detail the resulting brane-world cosmologies. Of particular interest are the properties of solutions when the brane-world approaches the black hole horizon. In this case the geometry induced on the brane is that of de Sitter, whose entropy and temperature is related to those of the higher dimensional bulk black hole.

Sign in / Sign up

Export Citation Format

Share Document