Weierstrass Type Representation for Marginally Trapped Surfaces in Minkowski 4-Space

Directly using the complex function theory and differential equation theory, we give a kind of Weierstrass representation formula for spacelike surfaces, especially, marginally trapped surfaces in 4-dimensional Minkowski space ${\mathbb E}^4_1$ .     

Null Surfaces and Their Singularities in Three-Dimensional Minkowski Space-Time

In this work we integrate the null geodesic equations in three-dimensional Minkowski space-time in order to obtain the light-cone cut function; that is, the function that describes the intersection, C_x ^a, of the light cone from each space-time point, _x ^a, with future null infinity I ⁺. Furthermore, using this result, we locate the singularities of the null surface obtained as the envelope of the past light cones from points on a deformed light-cone cut of I ⁺.     

Rotations with unit timelike quaternions in Minkowski 3-space

With the aid of quaternion algebra, rotation in Euclidean space may be dealt with in a simple manner. In this paper, we show that a unit timelike quaternion represents a rotation in the Minkowski 3-space. Also, we express Lorentzian rotation matrix generated with a timelike quaternion.     

Reconstructions of the Electron Dynamics in Magnetic Field and the Geometry of Complex Fermi Surfaces

Journal of Experimental and Theoretical Physics - The paper considers the semiclassical dynamics of electrons on complex Fermi surfaces in the presence of strong magnetic fields. The...     

Geometry of theSU 3 group

A parametrization of theSU ₃ group is given which is regular in the neighborhood of the unit element. The left-invariant differential forms are explicitly calculated, and a left- and right-invariant metric tensor is exhibited in these parameters.Work supported in part by a grant from Research Corporation, Providence, Rhode Island.     

Pitch functions of ruled surfaces and B-scrolls in Minkowski 3-space

In this paper, we define pitch function for any non developable ruled surfaces and use this notion to give a new characterization of B-scrolls in Minkowski 3-space.     

Equivariant Self-Similar Wave Maps from Minkowski Spacetime into 3-Sphere

We prove existence of a countable family of spherically symmetric self-similar wave maps from 3+1 Minkowski spacetime into the 3-sphere. These maps can be viewed as excitations of the ground state solution found previously by Shatah. The first excitation is particularly interesting in the context of the Cauchy problem since it plays the role of a critical solution sitting at the threshold for singularity formation. We analyze the linear stability of our wave maps and show that the number of unstable modes about a given map is equal to its nodal number. Finally, we formulate a condition under which these results can be generalized to higher dimensions. Received: 20 October 1999 / Accepted: 12 May 2000     

Fermion-meron interactions in Minkowski space-time

The interaction between massless isospinor fermions and a class of regular (classical) Yang-Mills fields in Minkowski space-time is analyzed. For the case in which the potential corresponds to the meron field of DeAlfaro, Fubini and Furlan the resulting Dirac equations are solved in general. Some properties of the general solution and the ensuing physical picture are briefly discussed.     

Meron-antimeron solution in Minkowski space

An elementary derivation, using Witten's Ansatz, is given of the elliptic meron-antimeron solution of the (Minkowski) SU(2) gauge theory in the W ₀=0 gauge.     

Casimir Effect for a Massless Spin-3/2 Field in Minkowski Spacetime

The Casimir effect has been studied for various quantum fields in both flat and curved spacetimes. As a further step along this line, we provide an explicit derivation of Casimir effect for massless spin-3/2 field with periodic boundary condition imposed in four-dimensional Minkowski spacetime. The corresponding results with Dirichlet ard Neumann boundary conditions are also discussed.     

Casimir Effect for a Massless Spin-3/2 Field in Minkowski Spacetime

The Casimir effect has been studied for various quantum fields in both fiat and curved spacetimes. As a further step along this line, we provide an explicit derivation of Casimlr effect for massless spin-3/2 field with periodic boundary condition imposed in four-dimensional Minkowski spacetime. The corresponding results with Dirichlet and Neumann boundary conditions are also discussed.     

3D black holes on a 2-brane in 4D Minkowski space

We investigate three-dimensional black hole solutions in the realm of pure and new massive gravity in 2+1 dimensions induced on a 2-brane embedded in a flat four-dimensional spacetime. There is no cosmological constant neither on the brane nor on the four-dimensional bulk. Only gravitational fields are turned on and we indeed find vacuum solutions as black holes in 2+1 dimensions even in the absence of any cosmological solution. There is a crossover scale that controls how far the three- or four-dimensional gravity manifests on the 2-brane. Our solutions also indicate that local BTZ and SdS₃ solutions can flow to local four-dimensional Schwarzschild-like black holes, as one probes from small to large distances, which is clearly a higher dimensional manifestation on the 2-brane. This is similar to the DGP scenario where the effects of extra dimensions for large probed distances along the brane manifest.     

Killing Symmetries of Generalized Minkowski Spaces, 3: Spacetime Translations in Four Dimensions

In this paper, we continue the study of the Killing symmetries of a N-dimensional generalized Minkowski space, i.e., a space endowed with a (in general non-diagonal) metric tensor, whose coefficients do depend on a set of non-metrical coordinates. We discuss here the translations in such spaces, by confining ourselves (without loss of generality) to the four-dimensional case. In particular, the results obtained are specialized to the case of a deformed Minkowski space (i.e. a pseudoeuclidean space with metric coefficients depending on energy).     

Superluminal transformations in complex Minkowski spaces

We calculate the mixing of real and imaginary components of space and time under the influence of superluminal boosts in thex direction. A unique mixing is determined for this superluminal Lorentz transformation when we consider the symmetry properties afforded by the inclusion of three temporal directions. Superluminal transformations in complex six-dimensional space exhibit unique tachyonic connections which have both remote and local space-time event connections.Supported in part by the Nuclear Science Division of the U.S. Department of Energy under contract No. W-7405-ENG-48.     

Minkowski domain walls in hyperbolic metamaterials

Minkowski domain walls are being actively considered in gravitation theory. They may form during a vacuum phase transition, or as a result of braneworld collision. Despite having interesting physical properties, Minkowski domain walls had remained in the theoretical domain only since their first introduction a few decades ago. Here we demonstrate how to make an electromagnetic analogue of a Minkowski domain wall using hyperbolic metamaterials. We analyze electromagnetic field behavior at the wall, and present a simple experimental model of “Minkowski domain wall” formation due to “collision” of two Minkowski spaces.     

Solving Bethe-Salpeter equation in Minkowski space

We develop a new method of solving the Bethe-Salpeter (BS) equation in Minkowski space. It is based on projecting the BS equation on the light-front (LF) plane and on the Nakanishi integral representation of the BS amplitude. This method is valid for any kernel given by the irreducible Feynman graphs. For massless ladder exchange, our approach reproduces analytically the Wick-Cutkosky equation. For massive ladder exchange, the numerical results coincide with the ones obtained by Wick rotation.