The irreducibility of a representation of a real Lie algebra may depend on whether the representation space is a real or complex Hilbert space. The unitary projective representations of the Poincare group on complex Hilbert spaces were studied by Wigner and many others. Although the Poincare group has a real Lie algebra, we do not know of any study of the orthogonal projective representations o...

Bile acid excretion was studied in 9 human subjects simultaneously by the Lindstedt (Lindstedt, S. 1957. Acta Physiol. Scand. 40:1-9) isotopic turnovermethod and by fecal chemical analysis during a balance study. The identities of the fecal bile acids were confirmed by combined gas-liquid chromatography/mass spectrometry. Under the steady state conditions of the patient studies, bile acid excre...

We do a study of the real representations of the Poincare group, motivated by the following: i) the classical electromagnetic field —from which the Poincare group was originally defined— transforms as a real representation of the Poincare group; ii) the localization of complex unitary representations of the Poincare group is incompatible with causality, Poincare covariance and energy positivity...

A new direct method for the computation of Lyapunov quantities (Lyapunov values or coefficients, Poincare-Lyapunov constants, focus values) for the second-order dynamical system, permitting us to narrow the requirements on a smoothness of system, is obtained.

Bile acid excretion was studied in 9 human subjects simultaneously by the Lindstedt (Lindstedt, S. 1957. Acta Physwl. Scand. 4O:l-9) isotopic turnover method and by fecal chemical analysis during a balance study. The identities of the fecal bile acids were confirmed by combined gas-liquid chromatography /mass spectrometry. Under the steady state conditions of the patient studies, bile acid excr...

The concept of Diff 4 invariant Poincare transformations is a cornerstone of T(opological) G(eometro)D(ynamics). This concept makes it possible to understand the concept of subjective time and irreversibelity as well as nontriviality of S-matrix at quantum level. In this paper the possibility of identifying Diff 4 invariant Poincare transformations as the recently discovered Lorentz invariant d...

the KAM theorem from a combinatorial viewpoint. Lindstedt, Newcomb and Poincaré introduced a remarkable trigonometric series motivated by the analysis of the three body problem, [P]. In modern language, [G2], it is the generating function, that I call Lindstedt series here, ~h(~ ψ) = ∑∞ k=1 ε k~h(k)(~ ψ) of the sequence ~h(k)(~ ψ) of trigonometric polynomials associated with well known combinat...