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Plasma cosmology

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Hannes Alfvén suggested that, by scaling laboratory results by a factor of 109, he could extrapolate magnetospheric conditions. Another scaling jump of 109 was required to extrapolate to galactic conditions, and a third jump of 109 was required to extrapolate to the Hubble distance. [1]

Plasma cosmology is a non-standard cosmology[2] generally attributed to a 1970 Nobel laureate named Hannes Alfvén.[3] Ionized gases, or plasmas, play the central part in plasma cosmology's explanation for the development of the universe, though dominated largely by electrodynamic forces rather than gravitational forces.[4] Alfvén proposed the use of plasma scaling to describe cosmological phenomena by extrapolating the results of sheltered terrestrial and space physics experiments to scales orders-of-magnitude greater.[1] Alfvén also hypothesized that matter and anti-matter, when stirred by the energetic output of their own annihilation reactions, formed a mixture of so-called ambiplasma by which matter and anti-matter would repel due to opposing magnetic fields.[citation needed]

Plasma cosmology contradicts the current consensus of astrophysicists that Einstein's Theory of general relativity explains the origin and evolution of the universe on its largest scales, relying instead on the further development of classical mechanics and electrodynamics in application to astrophysical plasmas[citation needed]. During the late 1980s to early 1990s there was limited discussion of the merits of plasma cosmology, and to this day many cosmologists are skeptical of the idea with almost no research devoted to plasma cosmology proposals.[5][6]

Cosmic plasma

Plasma physics is accepted uncontroversially to have great influence on many astrophysical phenomena due in part to plasma's ubiquity. Hannes Alfvén devoted much of his professional career attempting to characterize plasmas, for which he was awarded the Nobel Prize in Physics for 1970.

Standard astrophysical structure formation models, particularly at the level of star systems, account for magnetic braking. Magnetic braking, much like friction, dissipates kinetic energy as heat. In star systems, this reduces the Newtonian centripetal forces of particles orbiting planets and stars, and those reductions facilitate their gravitational collapse. However, galaxy groups and clusters have a lower plasma density by several orders of magnitude, and magnetic fields are not observed to be strong enough to significantly affect virializing processes.[7] Thus, the result of standard modeling of galaxy formation and structure is controlled by the mass distribution of the simulated system rather than its electrodynamic interactions.[8]

Alfvén's view of plasma's role in the universe differs from the standard view. Chief among these is his assertion that electromagnetic forces are equal in importance with gravitation on the largest distance scales.[9] Alfvén arrived at this conclusion when he extrapolated plasma phenomena from small to large distance scales.[1] However, Alfvén's models do not predict Hubble's law, the abundance of light elements, or the existence of the cosmic microwave background.[10]

A study in 1978 concluded that Alfvén's model of certain plasma flows, known as Birkeland currents, inaccurately explained star formation.[11] Alfvén and his supporters hypothesized that Birkeland currents were responsible for many filamentary structures. However, large-scale Birkeland currents have not been observed and the length scale for charge neutrality is predicted by astrophysicists to be far smaller than the relevant cosmological scales.[12]

Alfvén and Klein cosmologies

The conceptual origins of plasma cosmology were developed during 1965 by Alfvén in his book Worlds-Antiworlds, basing some of his work on the ideas Kristian Birkeland first described at the turn of the century and Oskar Klein's earlier proposal that astrophysical plasmas had an important influence on galaxy formation. During 1971, Klein extended Alfvén's proposals and develop the "Alfvén-Klein model" of cosmology. Their cosmology relied on giant astrophysical explosions resulting from a hypothetical mixing of cosmic matter and antimatter that created the universe or meta-galaxy as they preferred to speculate (see the Shapley-Curtis debate for more on the history of distinguishing between the universe and the Milky Way galaxy). This hypothetical substance that spawned the universe was termed "ambiplasma" and took the forms of proton-antiprotons (heavy ambiplasma) and electrons-positrons (light ambiplasma). In Alfvén's cosmology, the universe contained heavy symmetric ambiplasma with protective light ambiplasma, separated by double layers. According to Alfvén, such an ambiplasma would be relatively long-lived as the component particles and antiparticles would be too hot and too low-density to annihilate with each other rapidly. Annihilation radiation would emanate from the double layers of plasma and antiplasma domains. The exploding double layer was also suggested by Alfvén as a possible mechanism for the generation of cosmic rays[13], x-ray bursts and gamma-ray bursts.[14]

Ambiplasma was proposed in part to explain the observed baryon asymmetry in the universe as being due to an initial condition of exact symmetry between matter and antimatter.[15] According to Alfvén and Klein, ambiplasma would naturally form pockets of matter and pockets of antimatter that would expand outwards as annihilation between matter and antimatter occurred at the boundaries. Therefore, they concluded that we must happen to live in one of the pockets that was mostly baryons rather than antibaryons. The processes governing the evolution and characteristics of the universe at its largest scale would be governed mostly by this feature.

Alfvén postulated that the universe has always existed[16] due to causality arguments and rejection of ex nihilo models as a stealth form of creationism.[17] The cellular regions of exclusively matter or antimatter would appear to expand in regions local to annihilation, which Alfvén considered as a possible explanation for the observed apparent expansion of the universe as merely a local phase of a much larger history.

In 1993, theoretical cosmologist Jim Peebles criticized the cosmology of Klein (1971), and Alfvén's 1966 book, Worlds-Antiworlds, writing that "there is no way that the results can be consistent with the isotropy of the cosmic microwave background radiation and X-ray backgrounds".[10]

Further developments

While plasma cosmology has never had the support of most astronomers or physicists, a few researchers have continued to promote and develop the approach, and publish in the special issues of the IEEE Transactions on Plasma Science that are co-edited by plasma cosmology proponent Anthony Peratt.[18] A few papers regarding plasma cosmology were published in other mainstream journals until the 1990s. Additionally, in 1991, Eric J. Lerner, an independent researcher in plasma physics and nuclear fusion, wrote a popular-level book supporting plasma cosmology called The Big Bang Never Happened. At that time there was renewed interest in the subject among the cosmological community (along with other non-standard cosmologies). This was due to anomalous results reported in 1987 by Andrew Lange and Paul Richards of UC Berkeley and Toshio Matsumoto of Nagoya University that indicated the cosmic microwave background might not have a blackbody spectrum. However, the final announcement (in April 1992) of COBE satellite data corrected the earlier contradiction of the Big Bang; the level of interest in plasma cosmology has since fallen such that little research is now conducted.

Comparison to mainstream cosmology

Plasma cosmology has been developed in much less detail than mainstream cosmology and lacks many of the major predictions and features of the current models. In mainstream cosmology, detailed simulations of the correlation function of the universe, primordial nucleosynthesis, and fluctuations in the cosmic microwave background radiation, based on the principles of standard cosmology and a handful of free parameters, have been made and compared with observations, including non-trivial consistency checks.[citation needed] Plasma cosmology generally provides qualitative descriptions and not any systematic explanation for the standard features of mainstream cosmological theories.

For example, the standard hierarchical models of galaxy and structure formation rely on inferred but undetectable dark matter collecting into the superclusters, clusters, and galaxies seen in the universe today. The size and nature of structure are based on an initial condition from the primordial anisotropies seen in the power spectrum of the cosmic microwave background.[19] Recent simulations show agreement between observations of galaxy surveys and N-body cosmological simulations of the Lambda-CDM model.[20] The mass estimates of galaxy clusters using gravitational lensing also indicate that there is a large quantity of dark matter present[21], an observation not explained by plasma cosmology models[citation needed].

Mainstream studies also suggest that the universe is homogeneous on large scales without evidence of the very large scale structure required by plasma filamentation proposals.[22] The largest galaxy number count to date, the Sloan Digital Sky Survey, corresponds well to the mainstream picture.[23]

Light element production without Big Bang nucleosynthesis (as required in plasma cosmology) has been discussed in the mainstream literature and was determined to produce excessive x-rays and gamma rays beyond that observed.[24][25] This issue has not been completely addressed by plasma cosmology proponents in their proposals.[26] Additionally, from an observational point of view, the gamma rays emitted by even small amounts of matter/antimatter annihilation should be easily visible using gamma ray telescopes. However, such gamma rays have not been observed. This could be resolved by proposing, as Alfvén did, that the bubble of matter we are in is larger than the observable universe. In order to test such a model, some signature of the ambiplasma would have to be looked for in current observations, and this requires that the model be formalized to the point where detailed quantitative predictions can be made. This has not been accomplished.

No proposal based on plasma cosmology trying to explain the cosmic microwave background radiation has been published since COBE results were announced. Proposed explanations are relying on integrated starlight and do not provide any indication of how to explain that the observed angular anisotropies of CMB power spectrum is (so low as) one part in 105. The sensitivity and resolution of the measurement of these anisotropies was greatly advanced by WMAP. The fact that the CMB was measured to be so isotropic, in line with the predictions of the big bang model, was subsequently heralded as a major confirmation of the Big Bang model to the detriment of alternatives.[27] These measurements showed the "acoustic peaks" were fit with high accuracy by the predictions of the Big Bang model and conditions of the early universe.

Notes

  1. ^ a b c Hannes Alfvén, "On hierarchical cosmology" (1983) Astrophysics and Space Science (ISSN 0004-640X), vol. 89, no. 2, January 1983, p. 313-324.
  2. ^ It is described as such by advocates and critics alike. In the February 1992 issue of Sky & Telescope ("Plasma Cosmology"), Anthony Peratt describes it as a "nonstandard picture". The open letter at www.cosmologystatement.org – which has been signed by Peratt and Lerner – notes that "today, virtually all financial and experimental resources in cosmology are devoted to big bang studies". The ΛCDM model big bang picture is typically described as the "concordance model", "standard model" or "standard paradigm" of cosmology here, and here.
  3. ^ Helge S. Kragh, Cosmology and Controversy: The Historical Development of Two Theories of the Universe, 1996 Princeton University Press, 488 pages, ISBN 069100546X (pp.482-483)
  4. ^ Alfven, Hannes O. G., "Cosmology in the plasma universe - an introductory exposition", IEEE Transactions on Plasma Science (ISSN 0093-3813), vol. 18, Feb. 1990, p. 5-10.
  5. ^ Plasma cosmology advocates Anthony Peratt and Eric Lerner, in an open letter cosigned by a total of 34 authors, state "An open exchange of ideas is lacking in most mainstream conferences", and "Today, virtually all financial and experimental resources in cosmology are devoted to big bang studies". [1]
  6. ^ Tom Van Flandern writes in The Top 30 Problems with the Big Bang, "For the most part, these four alternative cosmologies [including Plasma Cosmology] are ignored by astronomers."
  7. ^ Colafrancesco, S. and Giordano, F. The impact of magnetic field on the cluster M - T relation Astronomy and Astrophysics, Volume 454, Issue 3, August II 2006, pp. L131-L134. [2] recount: "Numerical simulations have shown that the wide-scale magnetic fields in massive clusters produce variations of the cluster mass at the level of ~ 5 − 10% of their unmagnetized value.... Such variations are not expected to produce strong variations in the relative [mass-temperature] relation for massive clusters."
  8. ^ See for example: Dekel, A. and Silk, J. The origin of dwarf galaxies, cold dark matter, and biased galaxy formation Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 303, April 1, 1986, p. 39-55.[3] where they model plasma processes in galaxy formation that is driven primarily by gravitation of cold dark matter.
  9. ^ H. Alfvén and C.-G. Falthammar, Cosmic electrodynamics (2nd edition, Clarendon press, Oxford, 1963). "The basic reason why electromagnetic phenomena are so important in cosmical physics is that there exist celestial magnetic fields which affect the motion of charged particles in space.... The strength of the interplanetary magnetic field is of the order of 10-4 gauss (10 nanoteslas), which gives the [ratio of the magnetic force to the force of gravity] ≈ 107. This illustrates the enormous importance of interplanetary and interstellar magnetic fields, compared to gravitation, as long as the matter is ionized." (p.2-3)
  10. ^ a b P. J. E. Peebles, Principles of Physical Cosmology, (1993) Princeton University Press, p. 207, ISBN 978-0691074283
  11. ^ Alfvén, H.; Carlqvist, P., "Interstellar clouds and the formation of stars" Astrophysics and Space Science, vol. 55, no. 2, May 1978, p. 487-509.
  12. ^ http://adsabs.harvard.edu/abs/2006astro.ph..9031S
  13. ^ Hannes Alfven, Cosmic plasma. Taylor & Francis US, 1981,IV.10.3.2, p.109. "Double layers may also produce extremely high energies. This is known to take place in solar flares, where they generate solar cosmic rays up to 10^9 to 10^10 eV."
  14. ^ Alfvén, H., "Double layers and circuits in astrophysics", (1986) IEEE Transactions on Plasma Science (ISSN 0093-3813), vol. PS-14, Dec. 1986, p. 779-793. Based on the NASA sponsored conference "Double Layers in Astrophysics" (1986)
  15. ^ H. Alfvén and C.-G. Falthammar, Cosmic electrodynamics (Clarendon press, Oxford, 1963). H. Alfvén, Worlds-antiworlds: antimatter in cosmology, (Freeman, 1966). O. Klein, "Arguments concerning relativity and cosmology," Science 171 (1971), 339.
  16. ^ Hannes Alfvén, "Has the Universe an Origin" (1988) Trita-EPP, 1988, 07, p. 6. See also Anthony L. Peratt, "Introduction to Plasma Astrophysics and Cosmology" (1995) Astrophysics and Space Science, v. 227, p. 3-11: "issues now a hundred years old were debated including plasma cosmology's traditional refusal to claim any knowledge about an 'origin' of the universe (e.g., Alfvén, 1988).
  17. ^ Alfvén, Hannes, "Cosmology: Myth or Science?" (1992) IEEE Transactions on Plasma Science (ISSN 0093-3813), vol. 20, no. 6, p. 590-600. See also [4]
  18. ^ (See IEEE Transactions on Plasma Science, issues in 1986, 1989, 1990, 1992, 2000, 2003, and 2007 Announcement 2007 here)
  19. ^ See e.g. P. J. E. Peebles, Large-scale structure of the universe (Princeton, 1980).
  20. ^ See, for example, the Virgo Consortium's large-scale simulation of "universes in boxes" with the largest voids reaching such sizes. See also F. Hoyle and M. S. Vogeley, Voids in the 2dF galaxy redshift survey, Astrophys. J. 607, 751–764 (2004) arXiv:astro-ph/0312533.
  21. ^ See e.g. M. Bartelmann and P. Schneider, Weak gravitational lensing, Phys. Rept. 340 291–472 (2001) arXiv:astro-ph/9912508.
  22. ^ P. J. E. Peebles, Principles of Physical Cosmology (Princeton, 1993). P. J. E. Peebles, Large-scale structure of the universe (Princeton, 1980).
  23. ^ M. Tegmark et al. (SDSS collaboration), "The three-dimensional power spectrum of galaxies from the Sloan Digital Sky Survey", Astrophysical J. 606 702–740 (2004). arXiv:astro-ph/0310725 The failure of alternative structure formation models is clearly indicated by the deviation of the matter power spectrum from a power law at scales larger than 0.5 h Mpc-1 (visible here).The authors comment that their work has "thereby [driven] yet another nail into the coffin of the fractal universe hypothesis..."
  24. ^ J.Audouze et al.', Big Bang Photosynthesis and Pregalactic Nucleosynthesis of Light Elements, 'Astrophysical Journal 293:L53-L57, 1985 June 15[5]
  25. ^ Epstein et al., The origin of deuterium, Nature, Vol. 263, September 16, 1976 point out that if proton fluxes with energies greater than 500 MeV were intense enough to produce the observed levels of deuterium, they would also produce about 1000 times more gamma rays than are observed.
  26. ^ Ref. 10 in "Galactic Model of Element Formation" (Lerner, IEEE Trans. Plasma Science Vol. 17, No. 2, April 1989 [6]) is J.Audouze and J.Silk, "Pregalactic Synthesis of Deuterium" in Proc. ESO Workshop on "Primordial Helium", 1983, pp. 71-75[7] Lerner includes a paragraph on "Gamma Rays from D Production" in which he claims that the expected gamma ray level is consistent with the observations. He cites neither Audouze nor Epstein in this context, and does not explain why his result contradicts theirs.
  27. ^ D. N. Spergel et al. (WMAP collaboration), "First year Wilkinson Microwave Anisotropy Probe (WMAP) observations: Determination of cosmological parameters", Astrophys. J. Suppl. 148 (2003) 175.

Further reading

  • Alfvén, Hannes:
  • Peratt, Anthony:
  • Wright, E. L. "Errors in "The Big Bang Never Happened"". See also: Lerner, E. J. "Dr. Wright is Wrong". Lerner's reply to the above.
  • IEEE Xplore, IEEE Transactions on Plasma Science, 18 issue 1 (1990), Special Issue on Plasma Cosmology including A. L. Peratt, "Plasma cosmology", IEEE T. Plasma Sci. 18, 1-4 (1990).
  • Various authors: "Introduction to Plasma Astrophysics and Cosmology", Astrophysics and Space Science, v. 227 (1995) p. 3-11. Proceedings of the Second IEEE International Workshop on Plasma Astrophysics and Cosmology, held from 10 to 12 May 1993 in Princeton, New Jersey
  • H. Alfvén, Worlds-antiworlds: antimatter in cosmology, (Freeman, 1966).
  • H. Alfvén, Cosmic Plasma (Reidel, 1981) ISBN 90-277-1151-8
  • E. J. Lerner, The Big Bang Never Happened, (Vintage, 1992) ISBN 0-679-74049-X
  • A. L. Peratt, Physics of the Plasma Universe, (Springer, 1992) ISBN 0-387-97575-6