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2024, Academia.edu
According to R.P. Kerr, a black hole need not contain a singularity. Such an assertion prompted this author to explore alternate black-hole models where a singularity is unnecessary. The models presented here show that a sufficiently large black hole could contain a universe; that an average black hole could contain a neutron star. This paper also shows why micro-black holes are untenable and why a typical black hole has a mass of at least approximately three solar masses. As an additional bonus, the models presented conserve quantum information inside the black holes, and, are consistent with black-hole entropy and temperature.
International Journal of Modern Physics A, 2002
We describe some specific quantum black hole model. It is pointed out that the origin of a black hole entropy is the very process of quantum gravitational collapse. The quantum black hole mass spectrum is extracted from the mass spectrum of the gravitating source. The classical analog of quantum black hole is constructed.
2008
The modern notion of a black hole singularity is considered with reference to the Schwarzschild solution to Einstein's field equations of general relativity. A brief derivation of both the original and the modern line elements is given. The argument is put forward that the singularity occurring within the Schwarzschild line element that has been associated with the radius of the black hole event horizon is, in fact, merely a mathematical occurrence and does not exist physically. The real aim here, however, is to attempt to open up the whole problem, draw some conclusions, but finally to urge everyone to consider the points raised with no preconceived opinions and then come to their own final conclusion.
We consider the fundamental issues which dominate the question about the existence or non-existence of black hole horizons and singularities from both of the theoretical and observational points of view, and discuss some of the ways that black hole singularities can be prevented from forming at a classical level, i.e. without arguments of quantum gravity. In this way, we argue that black holes could have a different nature with respect with respect to the common belief. In fact, even remaining very compact astrophysics objects, they could be devoid of horizons and singularities. ``An important point is that it has been recently shown that the true BHs should have M = 0, hence the so called BHs could be something else [28].''
Journal of High Energy Physics, Gravitation and Cosmology, 2019
Applied Physics Research, 2019
With recent detection of black hole mergers by LIGO, the 'Black Holes' and 'Neutron Stars' have become common household names, albeit fanciful names in public domain. However, for the scientific community black holes are the ultimate paradoxes of nature. The claimed observations of black hole mergers are in fact interpretations of certain observations under the spacetime model of Relativity. These interpretations can change significantly with the change in operating model of the phenomenon. A black hole is believed to be a 'region of spacetime' exhibiting such strong gravitational effects that nothing, not even light can escape from it. We demonstrate in this paper that this conviction is based on erroneous derivation for the gravitational redshift and the correct derivation shows that a photon cannot be prevented from escaping a gravitating body of any mass and size. Due to erroneous depiction of spacetime as a physical entity in GR, a mathematical singularity predicted by Schwarzschild metric solution of EFE has been projected as a physical possibility in the form of Black Holes. To strengthen the physical basis of Black Hole creation, the observations of Super Nova explosions are being interpreted under core collapse models. The core collapse models are now regarded as the physical foundation of Black Holes and Neutron stars. In this paper we have established the invalidity of current core collapse models on the grounds of treating electrons, ions and nuclei as non-interacting particles and using kinetic theory of gases for analyzing compressive stresses in solid iron core.
Medicinal and Aromatic Plant Science and Biotechnology, 2012
Minerals have a diversified role in medicinal plant metabolism. Severity or scarcity of these causes multifarious effects in plant metabolism. Each and every aspect of plant biochemistry, physiology, anatomy, etc. is affected due to mineral nutrient composition of soils. Medicinal plants inherit resistance due to biosynthesis of bioactive substances (secondary metabolites) against the various types of diseases caused due to fungus, bacteria, viruses, mycoplasmas, insects and pests. The concentration of these minerals of both group i.e. activators or inhibitors present in the soil play a vital role in secondary plant metabolism. Minerals also play a major role in the reproduction of these medicinally important plants. Bioactive molecules of medical relevancy such as alkaloids, flavonoids, lignans, lipids, carbohydrates, resins, glycosides, phenolic compounds, volatile oils, vitamins, tannins etc. produced through various biosynthetic pathways of plants are a boon to urban, hilly and remote population of each nation. However, soils with different compositions of mineral elements adversely influence the metabolic activities of such valuable medicinal plants. Various physiological activities are governed through important mineral elements present in soils from where these are transferred to area where their need arises. So, accumulation and biosynthesis of these bioactive molecules in a plant system are widely dependent on the availability of mineral elements in the soil. Different developmental stages of the medicinal plants need supplementation of different macro-and micro-elements during its various growth and biosynthesis steps. This review deals with regulatory role of various mineral elements in each biological activities of different medicinal plants viz. Papaver, Catharanthus, Withania etc.
"The author is a scientist with peer-reviewed publications and a Ph.D. in cell and developmental biology from Harvard University. His knowledge of the material—historical and contemporary—and the rigor of his analysis are unimpeachable". Kirkus review.
Indo-European Linguistics and classical philology, 2024
GEBURTEN KIRCHE, 1991
Kabarak Journal of Law and Ethics, 2022
The Routledge Handbook of Second Language Acquisition, Morphosyntax, and Semantics, 2024
Cordis Revista Eletronica De Historia Social Da Cidade Issn 2176 4174, 2011
GEOPHYSICS, 2011
Guardianas. Las Mujeres de Guardia de Hierro, 2007
Uchenye Zapiski Kazanskogo Universiteta. Seriya Gumanitarnye Nauki, 2020
Nineteenth-Century French Studies, 2008
4-6 June 2025, University of Münster, Germany
Molecular Cell, 2008
The Professional Medical Journal, 2020
Número 6, Enero-Junio, 2018
Current Pediatric Reviews, 2005