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the black hole equilibrium problem been solved
 in Proc. of the 8th Marcel Grossmann Meeting on Relativistic Astrophysics  MG 8
, 1997
"... Abstract. When the term “black hole ” was originally coined in 1968, it was immediately conjectured that the only pure vacuum equilibrium states were those of the Kerr family. Efforts to confirm this made rapid progress during the “classical phase ” from 1968 to 1975, and some gaps in the argument h ..."
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Abstract. When the term “black hole ” was originally coined in 1968, it was immediately conjectured that the only pure vacuum equilibrium states were those of the Kerr family. Efforts to confirm this made rapid progress during the “classical phase ” from 1968 to 1975, and some gaps in the argument have been closed during more recent years. However the presently available demonstration is still subject to undesirably restrictive assumptions such as nondegeneracy of the horizon, as well as analyticity and causality in the exterior. 1
Energy dominance and the Hawking Ellis vacuum conservation theorem
"... Abstract. At a time when uninhibited speculation about negative tension – and by implication negative mass density – world branes has become commonplace, it seems worthwhile to call attention to the risk involved in sacrificing traditional energy positivity postulates such as are required for the cl ..."
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Abstract. At a time when uninhibited speculation about negative tension – and by implication negative mass density – world branes has become commonplace, it seems worthwhile to call attention to the risk involved in sacrificing traditional energy positivity postulates such as are required for the classical vacuum stability theorem of Hawking and Ellis. As well as recapitulating the technical content of this reassuring (when applicable) theorem, the present article provides a new, rather more economical proof. 1. Introduction. Although overshadowed by other more recent contributions – such as the noboundary recipe for creation of an entire universe – one of the most obvious subjects for reminiscence on the auspicious occasion of this 60th birthday celebration for Stephen Hawking is his central role in the foundation of classical
Fast Quantum Algorithms for Handling Probabilistic and Interval Uncertainty
, 2003
"... this paper, we show how the use of quantum computing can speed up some computations related to interval and probabilistic uncertainty. We end the paper with speculations on whether (and how) "hypothetic" physical devices can compute NPhard problems faster than in exponential time ..."
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Cited by 7 (7 self)
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this paper, we show how the use of quantum computing can speed up some computations related to interval and probabilistic uncertainty. We end the paper with speculations on whether (and how) "hypothetic" physical devices can compute NPhard problems faster than in exponential time
Exotic Material as Interactions Between Scalar Fields”, Progress in Physics 2, 24, (2006), proceedings of Space Technology and Applications International Forum (STAIF2005), edited by
 AIP Conference Proceedings 504
, 2005
"... Many theoretical papers refer to the need to create exotic materials with average negative energies for the formation of space propulsion anomalies such as “wormholes” and “warp drives”. However, little hope is given for the existence of such material to resolve its creation for such use. From the s ..."
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Many theoretical papers refer to the need to create exotic materials with average negative energies for the formation of space propulsion anomalies such as “wormholes” and “warp drives”. However, little hope is given for the existence of such material to resolve its creation for such use. From the standpoint that nonminimally coupled scalar fields to gravity appear to be the current direction mathematically. It is proposed that exotic material is really scalar field interactions. Within this paper the GinzburgLandau (GL) scalar fields associated with superconductor junctions is investigated as a source for negative vacuum energy fluctuations, which could be used to study the interactions among energy fluctuations, cosmological scalar (i. e., Higgs) fields, and gravity. 1
τ l
"... The spinor representation of the Lorentz group does not accept simple generalization with the group GL(4, R) of general linear coordinate transformations. The Dirac equation may be written for an arbitrary choice of a coordinate system and a metric, but the covariant linear transformations of the fo ..."
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The spinor representation of the Lorentz group does not accept simple generalization with the group GL(4, R) of general linear coordinate transformations. The Dirac equation may be written for an arbitrary choice of a coordinate system and a metric, but the covariant linear transformations of the fourcomponent Dirac spinor exist only for isometries. For usual diagonal Minkowski metric the isometry is the Lorentz transformation. On the other hand, it is possible to define the Dirac operator on the space of antisymmetric (exterior) forms, and in such a case the equation is covariant for an arbitrary general linear transformation. The space of the exterior forms is sixteendimensional, but usual Dirac equation is defined for fourdimensional complex space of Dirac spinors. Using suggested analogy, in present paper is discussed possibility to consider the space of Dirac spinors as some “subsystem ” of a bigger space, where the group GL(4, R) of General Relativity acts in a covariant way. For such purposes in this article is considered both Grassmann algebra of complex antisymmetric forms and Clifford algebra of Dirac matrices. Both algebras have same dimension as linear spaces, but different structure of multiplication. The underlying sixteendimensional linear space also may be considered either as space of complex 4 ×4 matrices, or as space of states of two particles: the initial Dirac spinor and some auxiliary system. It is shown also, that such approach is in good agreement with well known idea to consider Dirac spinor as some ideal of Clifford algebra. Some other possible implications of given model are also discussed. r
τ l
"... The spinor representation of the Lorentz group does not accept simple generalization with the group GL(4, R) of general linear coordinate transformations. The Dirac equation may be written for an arbitrary choice of a coordinate system and a metric, but the covariant linear transformations of the fo ..."
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The spinor representation of the Lorentz group does not accept simple generalization with the group GL(4, R) of general linear coordinate transformations. The Dirac equation may be written for an arbitrary choice of a coordinate system and a metric, but the covariant linear transformations of the fourcomponent Dirac spinor exist only for isometries. For usual diagonal Minkowski metric the isometry is the Lorentz transformation. On the other hand, it is possible to define the Dirac operator on the space of antisymmetric (exterior) forms, and in such a case the equation is covariant for an arbitrary general linear transformation. The space of the exterior forms is sixteendimensional, but usual Dirac equation is defined for fourdimensional complex space of Dirac spinors. Using suggested analogy, in present paper is discussed possibility to consider the space of Dirac spinor as some “subsystem ” of a bigger space, where the group GL(4, R) of general relativity acts in a covariant way. For such purposes in this article is considered both Grassmann algebra of complex antisymmetric forms and Clifford algebra of Dirac matrices. Both algebras have same dimension as linear spaces, but different structure of multiplication. The underlying sixteendimensional linear space also may be considered either as space of complex 4 × 4 matrices, or as space of states of two particles, there state of initial Dirac spinor is situated as subsystem. It is shown also, that such approach is in good agreement with well known idea to consider Dirac spinor as some ideal of Clifford algebra. Some other possible implications of given model are also discussed. r
mlq header will be provided by the publisher Fast Quantum Algorithms for Handling Probabilistic and Interval Uncertainty
, 2003
"... In many reallife situations, we are interested in the value of a physical quantity y that is difficult or impossible to measure directly. To estimate y, we find some easiertomeasure quantities x1,..., xn which are related to y by a known relation y = f(x1,..., xn). Measurements are never 100 % ac ..."
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In many reallife situations, we are interested in the value of a physical quantity y that is difficult or impossible to measure directly. To estimate y, we find some easiertomeasure quantities x1,..., xn which are related to y by a known relation y = f(x1,..., xn). Measurements are never 100 % accurate; hence, the measured values ˜xi are different from xi, and the resulting estimate ˜y = f(˜x1,..., ˜xn) is different from the desired value y = f(x1,..., xn). How different can it be? Traditional engineering approach to error estimation in data processing assumes that we know the probabildef ities of different measurement errors ∆xi = ˜xi − xi. In many practical situations, we only know the upper bound ∆i for this error; hence, after the measurement, the only information that we have about xi is that it def belongs to the interval xi = [˜xi − ∆i, ˜xi + ∆i]. In this case, it is important to find the range y of all possible values of y = f(x1,..., xn) when xi ∈ xi. We start the paper with a brief overview of the computational complexity of the corresponding interval computation problems. Most of the related problems turn out to be, in general, at least NPhard. In this paper, we show how the use of quantum computing can speed up some computations related to interval and probabilistic uncertainty. We end the paper with speculations on whether (and how) “hypothetic ” physical devices can compute NPhard problems faster than in exponential time. Most of the paper’s results were first presented at NAFIPS’2003 [30]. Copyright line will be provided by the publisher 1 Introduction: Data Processing