Algebraic and geometric structures of Special Relativity

Einstein's Special Relativity: The Hyperbolic Geometric Viewpoint

The analytic hyperbolic geometric viewpoint of Einstein's special theory of relativity is presented.

The Boosts in the Noncommutative Special Relativity

From the quantum analog of the Iwasawa decomposition of $SL(2,C)$ group and the correspondence between quantum $SL(2,C)$ and Lorentz groups we deduce the different properties of the Hopf algebra representing the boost of particles in noncommutative special relativity. The representation of the boost in the Hilbert space states is investigated and the addition rules of the velocities are established from the coaction. The q-deformed Clebsch-Gordon coefficients descibing the transformed states of the evolution of particles in noncommutative special relativity are introduced and their explicit ca…

Space-time and special relativity from causal networks

We show how the Minkowskian space-time emerges from a topologically homogeneous causal network, presenting a simple analytical derivation of the Lorentz transformations, with metric as pure event-counting. The derivation holds generally for d=1 space dimension, however, it can be extended to d>1 for special causal networks.

Special Relativity over the Field of Rational Numbers

We investigate the question: what structures of numbers (as physical quantities) are suitable to be used in special relativity? The answer to this question depends strongly on the auxiliary assumptions we add to the basic assumptions of special relativity. We show that there is a natural axiom system of special relativity which can be modeled even over the field of rational numbers.

Special relativity in complex vector algebra

Many different mathematical languages have been invented to describe the ideas of Einstein's special relativity. One of the most powerful languages is the Minkowski space-time algebra of D. Hestenes. We discuss the ideas of special relativity in a complex 4-dimensional algebra of observables, which is algebraically isomorphic to the even subalgebra of Hestenes' space-time algebra.

Velocity addition in Special Relativity and in Newtonian Mechanics are isomorphic

In the one dimensional case, velocity addition in Special Relativity and in Newtonian Mechanics, respectively, are each a commutative group operation, and the two groups are isomorphic. There are infinitely many such isomorphisms, each indexed by one positive real parameter.

Dotted and Undotted Algebraic Spinor Fields in General Relativity

We investigate using Clifford algebra methods the theory of algebraic dotted and undotted spinor fields over a Lorentzian spacetime and their realizations as matrix spinor fields, which are the usual dotted and undotted two component spinor fields. We found that some ad hoc rules postulated for the covariant derivatives of Pauli sigma matrices and also for the Dirac gamma matrices in General Relativity cover important physical meaning, which is not apparent in the usual matrix presentation of the theory of two components dotted and undotted spinor fields. We also discuss some issues related to…

Comparison of the nonrelativistic limit of Amelino-Camelia and MS Doubly Special Relativity

This paper is devoted to the study of the nonrelativitic limit of Amelino-Camelia Doubly Special Relativity, and the corresponding modified Klein-Gordon and Dirac equations. We show that these equations reduce to the Schrodinger equations for the particle and the antiparticle with different inertial masses. However, their rest masses are the same. M. Coraddu and S. Mignemi have studied recently the non relativistic limit of the Magueijo-Smolin Doubly Special Relativity. We compare their results with our study, and show that these two models are reciprocal to each other in the nonrelativitic li…

Gyrogroups, the Grouplike Loops in the Service of Hyperbolic Geometry and Einstein's Special Theory of Relativity

In this era of an increased interest in loop theory, the Einstein velocity addition law has fresh resonance. One of the most fascinating aspects of recent work in Einstein's special theory of relativity is the emergence of special grouplike loops. The special grouplike loops, known as gyrocommutative gyrogroups, have thrust the Einstein velocity addition law, which previously has operated mostly in the shadows, into the spotlight.

On the formal statement of the special principle of relativity

The aim of the paper is to develop a proper mathematical formalism which can help to clarify the necessary conceptual plugins to the special principle of relativity and leads to a deeper understanding of the principle in its widest generality.

关于Andréka猜想：狭义相对论是经典运动学唯一可能的概念归约

On Andréka's Conjecture that special relativity is the only possible conceptual reduct of classical kinematics

该研究通过纯数学证明验证了Andréka猜想，表明定义等价下不存在介于狭义相对论与晚期经典运动学的时空中间模型，为解释转向狭义相对论的历史必然性提供了数理依据。