A CPT anomaly

Threshold analyses and Lorentz violation

“…Moreover, a mechanism that could cause spontaneous Lorentz and CPT breaking in the framework of string field theory was discovered more than a decade ago [1]. Subsequent investigations have considered the possibility of Lorentz violation in other contexts, such as spacetime foam [2,3], nontrivial spacetime topology [4], loop quantum gravity [5], realistic noncommutative field theories [6], and spacetime-varying couplings [7]. Low-energy effects of Lorentz breaking are described by the Standard-Model Extension (SME) [8][9][10][11][12].…”

Gravitational anomaly and fundamental forces

“…As a consequence one can derive the condition, that there must be an even number of fermions in the fundamental representation [18][19][20][21]. For the connection with four-dimensional physics see [22,23].…”

Deriving Spin within a Discrete-Time Theory

“…3 The hamiltonian representation of the theory is obtained by introducing, besides the (constant) zero-th order momentum p µ [0] given by eq. (13), the other (non-constant) l-th order mo-…”

“…The concept of an elementary time-duration (a "quantum of time") has recently returned into fashion in GUTs [1], in String Theories [2], in Quantum Gravity [3], and in the approaches regarding spacetime either as a sort of quantum ether, or as a spacetime foam [4], or as endowed with a non-commutative geometry (like in Deformed or Double Special Relativity [5] 1 ). In particolar, the M-theory and the Loop Quantum Gravity (as in its version with semiclassical spin-network structure of spacetime) [6] lead even to a discrete space-time, in which a fundamental time-scale (or, equivalently, a mass-energy scale) naturally arises, besides and c.…”