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    BICEP2 Data, CMB B-modes, Inflation, Alternative Cosmologies... (I)
    By Luis Gonzalez-Mes... | May 17th 2014 07:54 AM | 3 comments | Print | E-mail | Track Comments
    About Luis

    Staff researcher at CNRS (France) in 1972-2013. Now leading the Cosmology Laboratory of the Megatrend University (Belgrade and Paris). For my work...

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    Two months after the controversial BICEP2 announcement, The Washington Post writes « Big Bang backlash: BICEP2 discovery of gravity waves questioned by cosmologists » and National Geographic emphasizes « Big Bang Discovery Comes Under Fire. Rumors ripple about flaws in the discovery of gravitational waves in the big bang's aftermath ». Both articles refer to the blog post « Is BICEP wrong? » by Adam Falkowski in Résonaances. Science did the same in « Blockbuster Big Bang Result May Fizzle, Rumor Suggests », and also Nature in « Gravitational wave discovery faces scrutiny » reporting « Cosmologist casts doubts on BICEP2's analysis of cosmic microwaves, but the team stands by its conclusions » on a recent lecture by Raphael Flauger at Princeton. By now, there is no new revised version of the BICEP2 article and its authors seem to confirm their experimental claim. The Planck collaboration is expected to provide in a few months its own E and B spectra of the cosmic microwave background (CMB) polarization. But what about the possible theoretical interpretations of the BICEP2 result, if the observed CMB B-modes really correspond to a signal from the early Universe? Alternatives to cosmic inflation exist, as I already pointed out in my posts « BICEP2, CMB B-modes And Spinorial Space-time » and « BICEP2, cosmic inflation, pre-Big Bang, SST, galactic effects... ».

    Another paper that has not been revised by its authors is « Fingerprints of Galactic Loop I on the Cosmic Microwave Background », arXiv:1404.1899, by Hao Liu, Philipp Mertsch and Subir Sarkar on the possible role of galactic dust in BICEP2 data. See also the statements by Philipp Mertsch in « Star dust casts doubt on recent big bang wave result » (New Scientist, 15 April 2014). The last results made public by the Planck collaboration (arXiv:1405.0871, arXiv:1405.0872, arXiv:1405.0873 and arXiv:1405.0874) do not yet clarify this situation. Again, the concerns are purely experimental and phenomenological, with nothing new about theoretical cosmology and possible alternatives to the inflationary scenario like those discussed in my March 28 article « CMB B-modes, spinorial space-time and Pre-Big Bang (I) ».

    The spinorial space-time

    The spinorial space-time (SST) with to complex cosmic coordinates corresponds to space and time such as they are seen by fermions (particles with half-integer spin). Il must therefore be considered as more fundamental than the standard relativistic space-time with four real coordinates. A specific property of the SST is that it automatically generates a privileged space direction (PSD) for each comoving observer. Then, local rotation modes around the privileged space direction in the early Universe may have produced CMB B-modes naturally providing an alternative to the inflationary scenario.

    The standard argument to interpret BICEP2 data as an evidence for inflation is that scalar (density) perturbations cannot produce B-modes in the polarization of the CMB, and that the only possibility to generate them is through tensor perturbations (gravitational waves). Vector perturbations (local rotational modes) are not really considered in such an approach. But if a local privileged space direction exists due to space-time geometry, local rotation around the PSD can be present in the early Universe and generate CMB B-modes.

    Recent Planck results (see arXiv:1303.5083) may have confirmed the existence of such a local privileged space direction.

    I discussed the SST properties and potentialities in two talks given at ICNFP 2012 and ICNFP 2013 :

    Pre-Big Bang, fundamental Physics and noncyclic cosmologies

    Pre-Big Bang, space-time structure, asymptotic Universe

    as well as in other recent papers :

    Cosmic rays and tests of fundamental principles (see the Post Scriptum)

    Planck data, spinorial space-time and asymptotic Universe

    Spinorial space-time and privileged space direction (I)

    Spinorial space-time and Friedmann-like equations (I)

    My last article :

    CMB B-modes, spinorial space-time and Pre-Big Bang (I)

    specifically discusses the issue of the interpretation of BICEP2 data. A second paper on the subject is in preparation.

    Pre-Big Bang patterns

    The spinorial space-time is just an example of how alternative cosmologies can naturally explain the BICEP2 data, assuming they really correspond to a signature from the early Universe.

    SST-based pre-Big Bang models can be at the origin of a new cosmology successfully replacing the standard approach. But other pre-Big Bang models can also account for the BICEP2 result.

    Even assuming that the BICEP2 signal corresponds to primordial gravitational waves, cosmic inflation is not the only way to generate them. The work by Grichka and Igor Bogdanoff, based on the evolution of a singular gravitational instanton from the zero space-time scale, provides an obvious illustration of this potentiality of pre-Big Bang models. It can be found at the adresses :

    http://tel.archives-ouvertes.fr/tel-00001502 (Grichka thesis, 1999, in French)

    http://tel.archives-ouvertes.fr/tel-00001503 (Igor thesis, 2002, in French with four published papers in English)

    Other pre-Big Bang models can be based on new ultimate constituents of matter, such as the superbradyons (superluminal preons) that I suggested in 1995. Then, as I pointed out the same year, primordial superluminal propagation naturally solves the horizon problem and inflation is no longer required. 

    In particular, superbradyons can be naturally incorporated in a pre-Big Bang cosmology using the spinorial space-time. More details can be found in my papers already mentioned, as well as in two other ICNFP 2012 and 2013 contributions :

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

    Ultra-high energy physics and standard basic principles

    Clearly, much further work is required before the cosmological origin of the primordial CMB B-modes possibly seen by BICEP2 can really be elucidated.

                                                                                 Luis Gonzalez-Mestres


    Luis Gonzalez-Mestres
    The new version of the BICEP2 paper, published by Physical Review Letters on June 19 :


    explicitly admits that the reported B-mode signal could be entirely due to polarized dust emission.

    Best regards
    Luis Gonzalez-Mestres
    Luis Gonzalez-Mestres
    See also :

    - my article BICEP2 Data, CMB B-modes, Inflation, Alternative Cosmologies... (II)

    - my transparencies presented at the ICNFP 2014 conference (plenary session of August 2), https://indico.cern.ch/event/277650/session/3/contribution/313/material/slides/1.pdf

    - my poster at the same conference (Kolymbari, Crete, 28 July - 6 August 2014)

    The ICNFP 2014 site : https://indico.cern.ch/event/277650/overview

    It was very useful and enlighteling to attend the ICNFP 2014 Conference.  For instance, the contributions on quantum entanglement encouraged me to add these remarks to my poster :


    Quantum mechanics can also be violated or deformed at ultra-high energy. Anomalous commutation relations (f.i. between components of momentum) can produce observable effects in UHECR.


    => Possible role of the propagation of superluminal signals ?

    The propagation of superluminal signals in vacuum was already tacitly assumed in the suggestion that standard scalar bosons and zero modes of harmonic oscillators are not permanently condensed in vacuum in the absence of surrounding standard matter (thus solving the cosmological constant problem). What, then, about the principles of quantum mechanics itself ?

    For the present status of work on the principles of quantum mechanics and their interpretation, see the contributions on quantum entanglement to this conference.

    In a superbradyonic vacuum, signals can propagate much faster than light. The natural limit being the superbradyonic critical speed cs => a possible relation between quantum mechanics and the ultimate structure of standard particles ?

    In the SST, spinorial wave functions also imply crossing the near past and future (local spinorial coordinates ξ - ξ0 around the particle position ξ0 ) => time does no longer have strict sense at such very small scales => possible measurable implications through basic quantum mechanics ?

    (see also forthcoming articles)
    James Ph. Kotsybar

    -- James Ph. Kotsybar

    What was there to slow cosmic inflation,
    which occurred shortly after the Big Bang?
    Nothing obstructed this fomentation,
    which from an infinitely dense point sprang.

    The claim is expansion somehow reduced
    its speed, the second after Creation,
    (yet, through observation, it’s been deduced
    there’s still a speed-limit violation).

    As though this were viewed -- aloof and astute --
    some claim the cosmos first increased its size,
    from sub-atomic limit to grapefruit,
    then paused, allowing heat to equalize.

    But no one can say what put on the brake
    and then released it for the heaven’s sake.

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