ABSTRACT We review some properties of solutions to 5D Einstein gravity with a discrete fifth dimension. Those properties depend on the discretization scheme we use. In particular, we find that the neglect of the lapse field (along the... more
ABSTRACT We review some properties of solutions to 5D Einstein gravity with a discrete fifth dimension. Those properties depend on the discretization scheme we use. In particular, we find that the neglect of the lapse field (along the discretized direction) gives rise to Randall–Sundrum-type metric with a negative tension brane. However, no brane source is required. The inclusion of the lapse field gives rise to solutions whose continuum limit is gauge fixed by the discretization scheme. We show also that the models allow a continuous mass spectrum for the gravitons with an effective 4D interaction at small scales.
We study a stationary "black" brane in M/superstring theory. Assuming BPS-type relations between the first-order derivatives of metric functions, we present general stationary black brane solutions with a traveling wave for the... more
We study a stationary "black" brane in M/superstring theory. Assuming BPS-type relations between the first-order derivatives of metric functions, we present general stationary black brane solutions with a traveling wave for the Einstein equations in D-dimensions. The solutions are given by a few independent harmonic equations (and plus the Poisson equation). General solutions are constructed by superposition of a complete set of those harmonic functions. Using the hyperspherical coordinate system, we explicitly give the solutions in 11-dimensional M theory for the case with M2-M5 intersecting branes and a traveling wave. Compactifying these solutions into five dimensions, we show that these solutions include the BMPV black hole and the Brinkmann wave solution. We also find new solutions similar to the Brinkmann wave. We prove that the solutions preserve the 1/8 supersymmetry if the gravi-electromagnetic field F, which is a rotational part of gravity, is self-dual. We also ...
This paper proposes an M-theory(MT)-derived special type of bijective particle (toy-)theory (BPT), in which each type geometric/topological entity (brane) is assigned one and only one type of physical particle and vice versa. BPT is... more
This paper proposes an M-theory(MT)-derived special type of bijective particle (toy-)theory (BPT), in which each type geometric/topological entity (brane) is assigned one and only one type of physical particle and vice versa. BPT is essentially a topological/geometrical toy-theory (and mainly an exercise of imagination) which tries to explain gravity as a quantum field mediated by 3 types of scale-specific hypothetical massless, heavy and ultra-heavy gravitons: BPT may be thus considered a “trigravity” toy-theory and proposes a way to (at least partially) fill the “gap” between M-Theory (on which BPT is based) and the Standard model (SM) of particle physics. BPT also offers alternative geometrical explanations for rest mass and for electromagnetic charge. This paper continues (from alternative angles of view) the work of other past articles/preprints of the same author in physics (listed from the newest to the oldest).
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In this paper we make a first step toward determining 4-dimensional data from higher dimensional superstring theory and considering these as underlying structures for the theory. First, we explore connections of exotic smoothings of R^4... more
In this paper we make a first step toward determining 4-dimensional data from higher dimensional superstring theory and considering these as underlying structures for the theory. First, we explore connections of exotic smoothings of R^4 and certain configurations of NS and D-branes, both classical and (generalized) quantum using C* algebras. Effects of some small exotic R^4's, when localized on S^3,