Pre-Big Bang, fundamental Physics and noncyclic cosmologies

Abstract

Abstract. Detailed analyses of WMAP and Planck data can have significant implications for noncyclic pre-Big Bang approaches incorporating a new fundamental scale beyond the Planck scale and, potentially, new ultimate constituents of matter with unconventional basic properties as compared to standard particles. Cosmic-ray experiments at the highest energies can also yield relevant information. Hopefully, future studies will be able to deal with alternatives: i) to standard physics for the structure of the physical vacuum, the nature of space-time, the validity of quantum field theory and conventional symmetries, the interpretation of string-like theories...; ii) to standard cosmology concerning the origin and evolution of our Universe, unconventional solutions to the cosmological constant problem, the validity of inflationary scenarios, the need for dark matter and dark energy... Lorentz-like symmetries for the properties of matter can then be naturally stable space-time configurations resulting from more general primordial scenarios that incorporate physics beyond the Planck scale and describe the formation and evolution of the physical vacuum. A possible answer to the question of the origin of half-integer spins can be provided by a primordial spinorial space-time with two complex coordinates instead of the conventional four real ones, leading to a really new cosmology. We discuss basic questions and phenomenological topics concerning noncyclic pre-Big Bang cosmologies and potentially related physics.

BICEP2, Planck, spinorial space-time, pre-Big Bang.

“…In particular, the leading contribution to the square of the Lundmark-Lemaître-Hubble [23] constant H is provided by a SST curvature term equal to t −2 whose sign does not depend on the space curvature felt by standard matter [24,37].…”

“…The conventional cosmological constant scenario can then be naturally avoided [23,81], as such a term is no longer necessary.to describe the evolution of the Universe.…”

“…The new term t −2 , of cosmic geometric origin as suggested by the SST structure and the H t = 1 law in the absence of matter, has a positive sign independent of k and dominates the large scale expansion of the Universe. K is a correction term accounting in particular for: -a possible small difference between the comoving frames of standard cosmology and those (preexisting) obtained from the underlying SST cosmic geometry; -similarly, a correction related to remnant effects from the pre-Big Bang era; -a reaction of the nucleated standard matter to the pre-existing expansion of the Universe led by the SST geometry and the pre-Big Bang vacuum [23,25];…”

High-energy cosmic rays and tests of basic principles of Physics

“…For instance, if objects with a critical speed c s c (superbradyons [13,23]) can exist in our Universe as free particles with speeds larger than c, they are expected to spontaneously emit "Cherenkow" radiation in the form of standard particles. If the superbradyon energy is high enough, some of these emissions can even be UHECR [7,8].…”

“…Even below ultrahigh energy (UHE), the appearance of exotic signatures cannot be excluded [20,21]. From a cosmological point of view, possible UHE violations of standard fundamental principles can possibly be related to pre-Big Bang scenarios [22,23] where the new physics would be expected to play a leading role.…”