BICEP2 data, cosmic inflation, Wikipedia information...
The recent results of the BICEP2 Collaboration on the polarization of cosmic microwave background (CMB) radiation have been at the origin of widespread statements presenting these results as an evidence for cosmic inflation. In a news release entitled « NASA Technology Views Birth of the Universe » referring to the claim by astronomers that they have « acquired the first direct evidence that gravitational waves rippled through our infant universe during an explosive period of growth called inflation », the NASA - CALTECH Jet Propulsion Laboratory estimated that « This is the strongest confirmation yet of cosmic inflation theories ». Simultaneously, a Stanford Report announcing « New evidence from space supports Stanford physicist's theory of how universe began » wrote « The detection of gravitational waves by the BICEP2 experiment at the South Pole supports the cosmic inflation theory of how the universe came to be ». The same kind of analysis appears in the New York Times articles « Space Ripples Reveal Big Bang’s Smoking Gun » (March 17) and « Ripples From the Big Bang » (March 24). However, things are not that simple, as pointed out by Luis Gonzalez-Mestres in his March 26 article « BICEP2, CMB B-modes and spinorial space-time » underlining that « pre-Big Bang patterns beyond conventional cosmology do not require inflation and can generate CMB B-modes » and that the arguments used to claim evidence for inflation do no longer hold « if a privileged space direction exists for each point of space-time, as automatically generated by the spinorial space-time (SST) I introduced in 1996-97 ». Indeed, if a privileged space direction exists for each comoving observer as is automatically the case in the Gonzalez-Mestres SST, CMB B-modes are easy to generate (rotation around the privileged space direction, vector product with this direction...) and nothing like inflation is required. Some attempts to censor this information in Wikipedia appear to have failed by now. It seems to us that the text on this cosmological issue added to the Wikipedia article on cosmic inflation is particularly relevant, as the Planck results may have confirmed the existence of a privileged space direction.
The text added by a contrbutor to the Wikipedia article on cosmic inflation is (see below) :
However, this assertion does not take into account possible nonstandard cosmological scenarios, including pre-Big Bang and the spinorial space-time suggested by Luis Gonzalez-Mestres in 1996-97.
(end of quote)
Yesterday's article by Gonzalez-Mestres « BICEP2, CMB B-modes and spinorial space-time » , http://www.science20.com/relativity_and_beyond_it/bicep2_cmb_bmodes_and_spinorial_spacetime-132616 , states :
In the SST pattern, the privileged space direction is an intrinsic property of space-time and was already present in the very early Universe. Then, a simple rotation around the privileged space direction generates a B-mode and the vector product of any E-like vector by this direction naturally leads to a B-like pseudovector. Such a scenario appears much less ad hoc than inflation.
The spinorial space-time describes and automatically expanding universe where the spinor modulus corresponds to the cosmic time (age of the Universe). Standard matter is then generated in an already expanding space, and can dynamically react (in particular, through gravitation) to this pre-existing expansion of purely geometric origin. This can be at the origin of a nonstandard contribution of gravitation to the generation of CMB B-modes.
(end of quote)
Available recent articles by Luis Gonzalez-Mestres on the spinorial space-time are :
Pre-Big Bang, fundamental Physics and noncyclic cosmologies, http://hal.archives-ouvertes.fr/hal-00795588
Planck data, spinorial space-time and asymptotic Universe, https://archive.org/details/PlanckSST
Spinorial space-time and privileged space direction (I), https://archive.org/details/PrivSpDir
Spinorial space-time and Friedmann-like equations (I), https://archive.org/details/SSTFriedmannbis
Also, in the last version of its article « Planck 2013 results. XXIII. Isotropy and statistics of the CMB », http://arxiv.org/abs/1303.5083 , the Planck Collaboration writes :
Indeed, when the power spectra of two hemispheres defined by a preferred direction are considered separately, one shows evidence for a deficit in power, while its opposite contains oscillations between odd and even modes that may be related to the parity violation and phase correlations also detected in the data.
(end of quote)
Here follows the beginning of the Wikipedia article in the absence of censoring (27 March 2014, 14h40)
From Wikipedia, the free encyclopedia
In physical cosmology, cosmic inflation, cosmological inflation, or just inflation is the expansion of space in the early universe at a rate much faster than the speed of light. The inflationary epoch lasted from 10−36 seconds after the Big Bang to sometime between 10−33 and 10−32 seconds. Following the inflationary period, the universe continues to expand, but at a slower rate.
The term "inflation" is used to refer to the hypothesis that inflation occurred, to the theory of inflation, or to the inflationary epoch. The inflationary hypothesis was proposed by American physicist Alan Guth based on theoretical models by Russian physicist Andrei Linde. The theory was later perfected by Linde himself, fixing some of the issues of Guth's model.
On 17 March 2014, astrophysicists of the BICEP2 collaboration announced the detection of possible inflationary gravitational waves in the B-mode power spectrum. Scientists working on standard cosmology claim that this result provides strong evidence for the theory of inflation. However, this assertion does not take into account possible nonstandard cosmological scenarios, including pre-Big Bang and the spinorial space-time suggested by Luis Gonzalez-Mestres in 1996-97.
As a direct consequence of inflation, the Universe appears to be the same in all directions (isotropic) and the cosmic microwave background radiation is distributed evenly. Inflation also explains the origin of the large-scale structure of the cosmos. Quantum fluctuations in the microscopic inflationary region, magnified to cosmic size, become the seeds for the growth of structure in the universe (see galaxy formation and evolution and structure formation).
(end of quote, Creative Commons Attribution-ShareAlike License)
The references are :
- Staff (17 March 2014). "BICEP2 2014 Results Release". National Science Foundation. Retrieved 18 March 2014.
- Clavin, Whitney (17 March 2014). "NASA Technology Views Birth of the Universe". NASA. Retrieved 17 March 2014.
- Overbye, Dennis (17 March 2014). "Space Ripples Reveal Big Bang’s Smoking Gun". The New York Times. Retrieved 17 March 2014.
- Overbye, Dennis (24 March 2014). "Ripples From the Big Bang". New York Times. Retrieved 24 March 2014.
- Chapter 17 of Peebles (1993).
- Ade, P. A. R.; Aikin, R. W.; Barkats, D.; Benton, S. J.; Bischoff, C. A.; Bock, J. J.; Brevik, J. A.; Buder, I.; Bullock, E.; Dowell, C. D.; Duband, L.; Filippini, J. P.; Fliescher, S.; Golwala, S. R.; Halpern, M.; Hasselfield, M.; Hildebrandt, S. R.; Hilton, G. C.; Hristov, V. V.; Irwin, K. D.; Karkare, K. S.; Kaufman, J. P.; Keating, B. G.; Kernasovskiy, S. A.; Kovac, J. M.; Kuo, C. L.; Leitch, E. M.; Lueker, M.; Mason, P.; Netterfield, C. B.; Nguyen, H. T.; O'Brient, R.; Ogburn, R. W. IV; Orlando, A.; Pryke, C.; Reintsema, C. D.; Richter, S.; Schwartz, R.; Sheehy, C. D.; Staniszewski, Z. K.; Sudiwala, R. W.; Teply, G. P.; Tolan, J. E.; Turner, A. D.; Vieregg, A. G.; Wong, C. L.; Yoon, K. W. (17 March 2014). BICEP2 I: Detection of B-mode Polarization at Degree Angular Scales (PDF). arXiv:submit/0934323.
- Luis Gonzalez-Mestres (24 February 1997). "Space, Time and Superluminal Particles".
- Inflation is in general not necessary in Pre-Big Bang patterns. Furthermore, in the spinorial space-time a privileged space direction is automatically generated for each comoving observer and naturally allows for B-modes in the cosmic microwave background radiation. The existence of such a privileged space direction may have been confirmed by recent Planck results.
- Luis Gonzalez-Mestres (26 March 2014). "BICEP2, CMB B-modes And Spinorial Space-time".
- Tyson, Neil deGrasse and Donald Goldsmith (2004), Origins: Fourteen Billion Years of Cosmic Evolution, W. W. Norton & Co., pp. 84–5.
(end of the reference list)
Indépendance des Chercheurs
Groupes de discussion :
Le Club est l'espace de libre expression des abonnés de Mediapart. Ses contenus n'engagent pas la rédaction.