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Plasma cosmology

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Hannes Alfvén used scaling laboratory results to extrapolate up to the scale of the universe. A scaling jump by a factor 109 was required to extrapolate to the magnetosphere, a second jump to extrapolate to galactic conditions, and a third jump to extrapolate to the Hubble distance.[1]

Plasma Cosmology is a laboratory model of astrophysics developed chiefly by Drs. Hannes Alfven, Winston H. Bostick, and moew recently Dr. Anthony Peratt of the Los Alamos National Laboratory. Its central postulate involves the dynamics of ionized plasmas in the solar system, galaxy and universe.[2][3]. In the words of Dr. Peratt, Plasma Cosmology has been under development "to address the growing recognition of the need for plasma physics in astrophysics," [4]

Many of the general concepts in Plasma Cosmology are attributed to Hannes Alfvén, who was awarded as a 1970 Nobel laureate for his work in magnetohydrodynamics (MHD).[3][5] Later, Alfvén proposed the use of plasma scaling to extrapolate the results of laboratory experiments and space plasma physics observations scaled across many orders-of-magnitude up to the largest observable objects in the universe. (See box[1])

The term Plasma Universe is sometimes used as a synonym for Plasma Cosmology,[2] being seen as the evolution of the plasma in the universe.[6][7]

Alfvén and cosmic plasma

An astrophysical extension of plasma science, Plasma Cosmology is accepted as having influence on many astrophysical phenomena. Much of the matter in the universe is thought to be ionized or exist as plasma, and it is this plasma that can generate magnetic fields. Much of Plasma Cosmology focuses on local phenomenon in the Solar System laboratory. Most notably, the Van Allen radiation belts, the solar wind, and terrestrial phenomenon such as Auroras.

Hannes Alfvén's in the 1960s to 1980s once suggested that plasma may play an important role in the universe, and asserted that electromagnetic forces are far more important than gravity when acting on interplanetary and interstellar charged particles.[8]

Alfvén hypothesized that Birkeland currents (here meaning currents in space plasmas which are aligned with magnetic field lines) were responsible for many filamentary structures and that a galactic magnetic field and associated current sheet, with an estimated galactic current of 1017 to 1019 amperes, might promote the contraction of interstellar clouds and may even constitute the main mechanism for contraction, initiating star formation.[9] The current standard view is that magnetic fields can hinder collapse, that large-scale Birkeland currents have not been observed, and that the length scale for charge neutrality is predicted to be far smaller than the relevant cosmological scales.[10]

Plasma Universe proposals

In the 1980s and 1990s, Alfvén and Anthony Peratt, a plasma physicist at Los Alamos National Laboratory, outlined a program they called the "Plasma Universe".[11][12][13] In plasma universe proposals, various plasma physics phenomena were associated with astrophysical observations and were used to explain extant mysteries and problems outstanding in astrophysics in the 1980s and 1990s. In various venues, Peratt profiled what he characterized as an alternative viewpoint to the mainstream models applied in astrophysics and cosmology.[12][13][14][15]

For example, Peratt proposed that the mainstream approach to galactic dynamics which relied on gravitational modeling of stars and gas in galaxies with the addition of dark matter was overlooking a possibly major contribution from plasma physics. He mentions laboratory experiments of Winston H. Bostick in the 1950s that created plasma discharges that looked like galaxies.[16][17] Perrat conducted computer simulations of colliding plasma clouds that he reported also mimicked the shape of galaxies.[18] Peratt proposed that galaxies formed due to plasma filaments joining in a z-pinch, the filaments starting 300,000 light years apart and carrying Birkeland currents of 1018 Amps.[19][20] Peratt also reported simulations he did showing emerging jets of material from the central buffer region that he compared to quasars and active galactic nuclei occurring without supermassive black holes. Peratt proposed a sequence for galaxy evolution: "the transition of double radio galaxies to radioquasars to radioquiet QSO's to peculiar and Seyfert galaxies, finally ending in spiral galaxies".[7] He also reported that flat galaxy rotation curves were simulated without dark matter.[19] At the same time Eric Lerner, an independent plasma researcher and supporter of Peratt's ideas, proposed a plasma model for then still-mysterious phenomenon of quasars based on a dense plasma focus.[21]

For a few decades, Peratt was able to promote and develop the Plasma Cosmology approach as a IEEE fellow of the IEEE Nuclear and Plasma Sciences Society. As a guest editor of the journal Transactions on Plasma Science, he supported the publication of a number of special issues dedicated to Plasma Cosmology, the last one appearing in 2007.[22] Additionally, in 1991, Lerner wrote a popular-level book supporting plasma cosmology titled The Big Bang Never Happened.[19]

Comparison to mainstream astrophysics

Proponents of Plasma Cosmology claim electrodynamics as an important factor in explaining the structure of the universe, and assert that it provides its own explanations for the evolution of galaxies[7] and formation of stars.[9] In particular the Plasma Cosmology paradigm has developed independent explanations for the flat rotation curves of spiral galaxies and to do away with the need for dark matter in galaxies and with the need for supermassive black holes in galaxy centres to power quasars and active galactic nuclei.[7][20] However, theoretical analysis shows that "many scenarios for the generation of seed magnetic fields, which rely on the survival and sustainability of currents at early times [of the universe are disfavored]",[10] i.e. Birkeland currents of the magnitude needed (say 1018 Amps) for galaxy formation are thought to not exist.[23]

Plasma Cosmology provides independent explanations for a variety of phenomenon including the Nucleosynthesis of Light Elements.[24] In 1995 Eric Lerner published his own explanation for the cosmic microwave background radiation (CMB).[25] He argues that his model can explain both the fidelity of the CMB spectrum to that of a black body and the low level of anisotropies found. The sensitivity and resolution of the measurement of the CMB anisotropies was greatly advanced by WMAP and Planck which have challenged and placed severe restrictions on every popular model of the cosmos.

References and Notes

  1. ^ a b Hannes Alfvén, "On hierarchical cosmology" (1983) Astrophysics and Space Science (ISSN 0004-640X), vol. 89, no. 2, January 1983, p. 313-324.
  2. ^ a b "Plasma Cosmology" (PDF). Sky & Telescope. 1992. Retrieved 26 May 2012. {{cite journal}}: Unknown parameter |authors= ignored (help); Unknown parameter |month= ignored (help)
  3. ^ a b His MHD research found that magnetic fields can induce currents in a moving conductive fluid, which in turn creates forces on the fluid and also changes the magnetic field itself.
  4. ^ Anthony L. Peratt, Physics of the Plasma Universe, 1991 Springer-Verlag, ISBN 0-387-97575-6
  5. ^ Helge S. Kragh, Cosmology and Controversy: The Historical Development of Two Theories of the Universe, 1996 Princeton University Press, 488 pages, ISBN 0-691-00546-X (pp.482-483)
  6. ^ Cite error: The named reference Alfven1990 was invoked but never defined (see the help page).
  7. ^ a b c d A. Peratt (1986). "Evolution of the Plasma Universe: II. The Formation of Systems of Galaxies" (PDF). IEEE Trans. on Plasma Science. PS-14: 763–778. ISSN 0093-3813.
  8. ^ 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)
  9. ^ a b Alfvén, H.; Carlqvist, P., "Interstellar clouds and the formation of stars" Astrophysics and Space Science, vol. 55, no. 2, May 1978, p. 487-509.
  10. ^ a b "Can Electric Charges and Currents Survive in an Inhomogeneous Universe?". arXiv. 2006. {{cite journal}}: Unknown parameter |authors= ignored (help); Unknown parameter |month= ignored (help)
  11. ^ H. Alfvén, Model of the Plasma Universe, IEEE Trans. Plasma Sci. Vol PS-14, 1986. [1]
  12. ^ a b A. L. Peratt, Plasma Cosmology: Part I, Interpretations of a Visible Universe, World & I, vol. 8, pp. 294-301, August 1989. [2]
  13. ^ a b A. L. Peratt, Plasma Cosmology:Part II, The Universe is a Sea of Electrically Charged Particles, World & I, vol. 9, pp. 306-317, September 1989 .[3]
  14. ^ A.L. Peratt, Plasma Cosmology, Sky & Tel. Feb. 1992. [4]
  15. ^ A. L. Peratt, Introduction to Plasma Astrophysics and Cosmology, Astrophys. Space Sci. 227, 3-11 (1995). [5]
  16. ^ A. Peratt (1986). "Evolution of the plasma universe. I - Double radio galaxies, quasars, and extragalactic jets" (PDF). IEEE Trans. on Plasma Science. PS-14: 639–660. ISSN 0093-3813.
  17. ^ Bostick, W. H., "What laboratory-produced plasma structures can contribute to the understanding of cosmic structures both large and small" (1986) IEEE Transactions on Plasma Science (ISSN 0093-3813), vol. PS-14, Dec. 1986, p. 703-717
  18. ^ "Evolution of Colliding Plasmas". Physical Review Letters. 44: 1767–1770. 20 June 1980. Bibcode:1980PhRvL..44.1767P. doi:10.1103/PhysRevLett.44.1767. {{cite journal}}: Unknown parameter |authors= ignored (help)
  19. ^ a b c E. J. Lerner (1991). The Big Bang Never Happened. New York and Toronto: Random House. ISBN 0-8129-1853-3.
  20. ^ a b "On the Evolution of Interacting, Magnetized, Galactic Plasmas". Astrophysics and Space Science. 91: 19–33. 1983. Bibcode:1983Ap&SS..91...19P. doi:10.1007/BF00650210. {{cite journal}}: Unknown parameter |authors= ignored (help)
  21. ^ E.J. Lerner (1986). "Magnetic Self‑Compression in Laboratory Plasma, Quasars and Radio Galaxies". Laser and Particle Beams. 4 part 2: 193‑222. Bibcode:1986LPB.....4..193L. doi:10.1017/S0263034600001750.
  22. ^ (See IEEE Transactions on Plasma Science, issues in 1986, 1989, 1990, 1992, 2000, 2003, and 2007)
  23. ^ 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. [6] 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."
  24. ^ Ref. 10 in "Galactic Model of Element Formation" (Lerner, IEEE Trans. Plasma Science Vol. 17, No. 2, April 1989 [7]) is J.Audouze and J.Silk, "Pregalactic Synthesis of Deuterium" in Proc. ESO Workshop on "Primordial Helium", 1983, pp. 71-75 [8] 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.
  25. ^ Eric Lerner. Intergalactic Radio Absorption and the COBE Data, Astrophysics and Space Science, 227: 61-81, 1995.

Further reading

  • Alfvén, Hannes:
  • Peratt, Anthony:
  • IEEE journal Transactions on Plasma Science: special issues on Space and Cosmic Plasma 1986, 1989, 1990, 1992, 2000, 2003, and 2007
  • Cambridge University Press journal Laser and Particle Beams: Particle Beams and Basic Phenomena in the Plasma Universe, a Special Issue in Honor of the 80th Birthday of Hannes Alfvén, vol. 6, issue 3, August 1988 [9]
  • 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
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