290 research outputs found
Non-Newtonian Gravity, Fluctuative Hypothesis and the Sizes of Astrophysical Structures
We show that the characteristic sizes of astrophysical and cosmological
structures, where gravity is the only overall relevant interaction assembling
the system, have a phenomenological relation to the microscopic scales whose
order of magnitude is essentially ruled by the Compton wavelength of the
proton. This result agrees with the absence of screening mechanisms for the
gravitational interaction and could be connected to the presence of Yukawa
correcting terms in the Newtonian potential which introduce typical interaction
lengths. Furthermore, we are able to justify, in a straightforward way, the
Sanders--postulated mass of a vector boson considered in order to obtain the
characteristic sizes of galaxies.Comment: 11 pages. to appear in Mod. Phys. Lett.
Inference of Planck action constant by a classical fluctuative postulate holding for stable microscopic and macroscopic dynamical systems
The possibility is discussed of inferring or simulating some aspects of
quantum dynamics by adding classical statistical fluctuations to classical
mechanics. We introduce a general principle of mechanical stability and derive
a necessary condition for classical chaotic fluctuations to affect confined
dynamical systems, on any scale, ranging from microscopic to macroscopic
domains. As a consequence we obtain, both for microscopic and macroscopic
aggregates, dimensional relations defining the minimum unit of action of
individual constituents, yielding in all cases Planck action constant.Comment: 14 pages, no figure
DYNAMICAL CONTROL OF THE HALO IN PARTICLE BEAMS: A STOCHASTIC–HYDRODYNAMIC APPROACH
In this paper we describe the beam distribution in particle accelerators in the framework of a stochastic–hydrodynamic scheme. In this scheme the possible reproduction of the halo after its elimination is a consequence of the stationarity of the transverse distribution which plays the role of an attractor for every other distribution. The relaxation time toward the halo is estimated, and a few examples of controlled transitions toward a permanent halo elimination are discussed
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