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] urged the application of laboratory and magnetospheric data, and ] of large-scale particle-in-cell simulations, to non-''in-situ'' space regions. Together with direct observation of interstellar and intergalactic plasma phenomenon, this leads them to predict a ''knowledge expansion'' about the universe, and a ''backflow of information'' about laboratory plasmas. (Click image to enlarge)]] ] urged the application of laboratory and magnetospheric data, and ] of large-scale particle-in-cell simulations, to non-''in-situ'' space regions. Together with direct observation of interstellar and intergalactic plasma phenomenon, this leads them to predict a ''knowledge expansion'' about the universe, and a ''backflow of information'' about laboratory plasmas. (Click image to enlarge)]]
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'''Plasma cosmology''' is a ] model based on the electromagnetic properties of ]s. Plasma cosmology explains the ] and evolution of the universe, from ] formation to the ] by invoking ] phenomena associated with laboratory plasmas. '''Plasma cosmology''' is a ] model based on the electromagnetic properties of ]s. Plasma cosmology explains the ] and evolution of the universe, from ] formation to the ] by invoking ] phenomena associated with laboratory plasmas.


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Plasma cosmology also differs from ] ]. Its advocates emphasize the links between physical ] on ] and those that govern the cosmos. Plasma cosmology is explained as much as possible in terms of known physics, using the theoretical and experimental results of laboratory ] in cosmological applications. Proponents contrast this with the ] which has over the course of its existence required the introduction of such features as ], ] and ] that have not been detectable yet in laboratory experiments. Plasma cosmology also differs from ] ]. Its advocates emphasize the links between physical ] on ] and those that govern the cosmos. Plasma cosmology is explained as much as possible in terms of known physics, using the theoretical and experimental results of laboratory ] in cosmological applications. Proponents contrast this with the ] which has over the course of its existence required the introduction of such features as ], ] and ] that have not been detectable yet in laboratory experiments.


Plasma cosmology was first developed by Swedish physicist ] in a book published in 1965. Alfvén is well-respected in the ] as the founder of modern ] together with ], ] and ].{{ref|early}} for which he received the ]. While plasma cosmology has never had the support of large numbers of ] or ], a small group of plasma physicists such as ] and ] have continued to promote and develop the approach. These physicists have been able to propose theories for the origin of ] (such as ]s, galaxies, and clusters and ]s of galaxies), for the synthesis of ], and for the origin of the ]. Although their theories are not generally accepted by the ], proponents argue that they could explain observations more easily, without introducing the "new physics" seen in the big bang theory. Plasma cosmology was first developed by Swedish physicist ] in a book published in 1965. Alfvén is well-respected in the ] as the founder of modern ] together with ], ] and ].{{ref|early}} for which he received the ]. While plasma cosmology has never had the support of large numbers of ] or ], a small group of plasma physicists such as ] and ] have continued to promote and develop the approach. These physicists have been able to propose theories for the origin of ] (such as ]s, galaxies, and clusters and ]s of galaxies), for the synthesis of ], and for the origin of the ]. Although their theories are not generally accepted by the ], proponents argue that they could explain observations more easily, without introducing the "new physics" seen in the big bang theory. Critics of the plasma cosmology point out that detailed observational testing of big bang cosmology is not rivalled by plasma cosmology and that the big bang theory is supported by multiple complementary quantitative tests.

==Alfvén's model== ==Alfvén's model==
]s and their application to physics and astronomy]] ]s and their application to physics and astronomy]]
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===Formation of structure=== ===Formation of structure===


In the early 1980’s ], a former student of ], used supercomputer facilities at Maxwell Laboratories and later at ] to simulate Alfvén and Fälthammar’s concept of galaxies being formed by clouds of plasma spinning in a magnetic filament. The simulation began with two spherical clouds of plasma trapped in parallel magnetic filaments, each carrying a current of around 10<sup>18</sup> amperes. In a video created from the simulation, the clouds begin to rotate around each other, spin on their own axes and distort their shape until a perfectly formed spiral galaxy emerges{{ref|spiral}}. Peratt showed that the stages of formation closely corresponded to observed galaxy shapes. In addition, the rotation curves of the simulated galaxy showed the same plateau in velocity as do real galaxies. In the early 1980’s ], a former student of ], used supercomputer facilities at Maxwell Laboratories and later at ] to simulate Alfvén and Fälthammar’s concept of galaxies being formed by primordial clouds of plasma spinning in a magnetic filament. The simulation began with two spherical clouds of plasma trapped in parallel magnetic filaments, each carrying a current of around 10<sup>18</sup> ]. In a video created from the simulation, the clouds begin to rotate around each other, spin on their own axes and distort their shape until a spiral shape emerges{{ref|spiral}}. Peratt claimed that the various stages in his simulation looked like observed galaxy shapes. Additionally, Perrat claimed that his model could explain the ] without invoking ].


The simulation did not contain gravitational forces, so even Perrat admitted it wasn't wholly realistic. Current ] rely on so-called hierarchical structure formation that is theoretically derivable from the ] of anisotropies seen in the ]. The mass estimates of ]s using ], which is an independent check from the rotation curves, also indicate that there is a large quantity of dark matter present independent of the measurements of galaxy rotation curves, causing the vast majority of astrophysicists to accept dark matter as a real phenomenon that cannot be explained by appeal to electromagnetic processes.{{ref|lensing}}
While the simulation did not contain gravitational forces, so could not be wholly realistic, it demonstrated that electromagnetic processes could lead to the forms observed at a galactic scale. The fact that electromagnetic processes are important for angular momentum transport in ] and ] is agreed upon by astrophysicists. In addition, Peratt has suggests that the flat ]s used by astrophysicists as evidence for dark matter in the outer reaches of galaxies are in fact due to galactic plasmas interacting with magnetic fields. This explanation was bolstered when, in 2005, observers found stars in the outer reaches of the Andromeda galaxy that were moving far slower than the plasma at the same radius.{{ref|Andromeda}} The stars experience a greater gravitational force than the plasma, relative to the magnetic force, so this observation is consistent with the idea that the observed flat rotation curves are due to magnetic forces, with less or perhaps no dark matter required. The observers, however, note that the stars likely joined the galaxy through a recent ] event, in which case they could not be considered part of the ] ]. Critics observe that mass estimates of clusters using ], which is an independent check from the rotation curves, also indicate that there is a large quantity of dark matter present.{{ref|lensing}}


In the mid-80’s Lerner used plasma filamentation theory to develop a general explanation of the large scale structure of the universe. Lerner claims that plasma cosmology can easily accommodate large scale structures and he predicts a fractal distribution of matter with density being inversely proportional to the distance of separation of objects. Plasma filamentation theory allows the mass of condensed objects formed to be predicted as a function of density. Magnetically confined filaments initially compress plasma, which is then condensed gravitationally into a fractal distribution of matter. However, critics of plasma cosmology argue that a fractal distribution seems to be ruled out by measurements of the large scale matter power spectrum, such as the ], which indicate a nearly scale-invariant ], rather than a fractal spectrum.{{ref|hzspect}}
During the same period, Lerner developed a plasma model of quasars based on the ] fusion device. In this device, converging filaments of current form a tight, magnetically confined ball of plasma on the axis of cylindrical electrodes. As the magnetic field of the ball, or ], decays, it generates tremendous electric fields that accelerate a beam of ions in one direction and a beam of electrons in the other. In Lerner’s model, the electric currents generated by a galaxy spinning in a intergalactic magnetic field converge on the center, producing a giant plasmoid, or quasar. This metastable entity, confined by the magnetic field of the current flowing through it, generates both the beams and intense radiation observed with quasars and active galactic nuclei. Lerner compared in detail the predictions of this model with quasar observations. In addition the quantitative model of the plasma focus developed in this work was used in efforts aimed at developing the device as a fusion generator.

In the mid-80’s Lerner used plasma filamentation theory to develop a general explanation of the large scale structure of the universe. While big bang cosmology has difficulty accommodating the formation of very large structures (such as voids 100 Mpc or more across) in the limited amount of time available since the hypothesized origin of the universe, plasma cosmology can easily accommodate large scale structures, and in fact firmly predicts a fractal distribution of matter with density being inversely proportional to the distance of separation of objects.

Plasma filamentation theory allows the mass of condensed objects formed to be predicted as a function of density. Magnetically confined filaments initially compress plasma, which is then condensed gravitationally. For this to happen, the plasma must be collisional. Otherwise, particles will just continue in orbits like the planets of the solar system. Given the characteristic ion velocity in the filament, calculated from instability theory, the collisional condition implies that objects of mass ''M'' = 1.8 ''n''<sup>-2</sup> form from plasma of initial density ''n'', where ''M'' is in solar masses and ''n'' in ions/cm<sup>3</sup>. This fractal scaling relationship (with fractal dimension equal to two) has been borne out by many studies on all observable scales of the universe.{{ref|fractal}} In addition, the numerical constant in the relation between mass and density, or equivalently, mass and separation of objects (''M'' = 9.7 x 10<sup>10</sup> ''R''<sup>2</sup>, where ''R'' is in ] and ''M'' is in solar masses) has been borne out by observation. However, critics of plasma cosmology argue that a fractal distribution seems to be ruled out by measurements of the large scale matter power spectrum, such as the ], which indicate a nearly scale-invariant ], rather than a fractal spectrum.{{ref|hzspect}}

In the plasma model, where superclusters, clusters and galaxies are formed from magnetically confined plasma vortex filaments, a break in the scaling relationship is only anticipated at scales greater than approximately 3 Gpc. Naturally, since the plasma approach does not hypothesize an origin in time for the universe, the large amounts of time needed to create large-scale structures present no problems for the theory.


===Light elements abundance=== ===Light elements abundance===


The structure formation theory allowed Lerner to calculate the size of stars formed in the formation of a galaxy and thus the amounts of ] and other light elements that will be generated during galaxy formation.{{ref|nucleosynthesis}} This led to the predictions that large numbers of intermediate mass stars (from 4-12 solar masses) would be generated during the formations of galaxies. These stars produce and emit to the environment large amounts of helium-4, but very little carbon, nitrogen and oxygen. Eric Lerner calculated the size of stars assuming Perrat's formation model and thus the amounts of ] and other light elements.{{ref|nucleosynthesis}} This led to the predictions that large numbers of intermediate mass stars (from 4-12 solar masses) would be generated during the formations of galaxies. Lerner claimed that his model for nucleosynthesis led to a broader range of predicted abundances than ], because the plasma theory hypothesizes a process occurring in individual galaxies, so some variation is to be expected. In addition ] are postulated to produce &ndash; by collisions with ambient hydrogen and helium &ndash; the observed amounts of ] and various isotopes of ].

The plasma calculations, which contained no free variables, lead to a broader range of predicted abundances than does ], because the plasma theory hypothesizes a process occurring in individual galaxies, so some variation is to be expected. The range of values predicted for <sup>4</sup>He is from 21.5 to 24.8%. However, the theory is still tested by the observations, since the minimum predicted value remains a firm lower limit (additional <sup>4</sup>He is of course produced in more mature galaxies). This minimum value is consistent with the minimum observed values of <sup>4</sup>He abundance, such as ], UM461, with an abundance of 21.9±0.8%.

In addition cosmic rays from these stars can produce &ndash; by collisions with ambient hydrogen and helium &ndash; the observed amounts of ] and lithium-7. Deuterium production by the p + p → d+] reaction has been predicted by plasma theory to yield abundances of the order of 2.2×10<sup>-5</sup>. This prediction was made in 1989, at a time when no observations of D in low-metallicity systems were available and the consensus values for primordial D from big bang theory were 3&ndash;4 times higher. Yet this predicted value lies within the range of observed "primordial" D values, although somewhat below the average D values.

In its present form, the absolute abundance of <sup>7</sup>Li has not been calculated in the plasma-stellar theory of light elements. However, the theory unambiguously predicted (as has the big bang theory) that the abundance depends on the C, N and O abundance from ] and subsequent observations have verified that prediction. Observations of the abundances of <sup>6</sup>Li &ndash; which is also generated by cosmic rays, but is destroyed much more readily in stars &ndash; are also consistent with a cosmic-ray origin for <sup>7</sup>Li.


===Microwave background=== ===Microwave background===


It has long been noted{{ref|hecmb}} that the amount of energy released in producing the observed amount of helium-4 is the same as the amount of energy in the cosmic microwave background (CMB). If such energy was released from intermediate-mass stars in the early stages of the formation of galaxies, the heavy dust in such galaxies would thermalize the radiation and re-emit it as far-IR. But what would convert this radiation into the extremely smooth and isotropic 2.7 K ] radiation of the CMB? In the later ‘80s Lerner, and Peratt and Peter independently hypothesized that the energy is thermalized and isotropized by a thicket of dense, magnetically confined plasma filaments that pervade the intergalactic medium.{{ref|cmb}} (Hoyle and Narlikar proposed a different mechanism to produce the same effect.{{ref|hn}}) Lerner was able to develop the model in some detail, accurately matching the spectrum of the CMB using the best-quality (high-galactic latitude) data set from ]. According to ] the amount of energy released in producing the observed amount of ] is the same as the amount of energy in the ] (CMB) since the ] and the ] were coupled during the production of nuclei. Plasma cosmology advocates claim that this correspondence, rather than being due to energetic photons driving universal nucleosynthesis, is explained by the stellar nucleosynthesis of helium releasing the required CMB energy from the stars in the early stages of the plasma cosmology's version of formation of galaxies. In order for such a model to yield the near-perfect observed ], Lerner, Peratt and others hypothesized that the energy is thermalized and isotropized by a thicket of dense, magnetically confined plasma filaments that pervade the intergalactic medium.{{ref|cmb}} Lerner developed this model, by matching the isotropic and homogeneous blackbody spectrum of the CMB using a fraction of the data set from ]. Critics have pointed out that, unlike the big bang model, plasma cosmology has not calculated the full detail angular power spectrum they would expect from their cosmic microwave background and compared it to the ] data.{{ref|WMAP}}


Since the WMAP observations have been touted by many in the ] as a "confirmation" of the Big Bang, plasma cosmology advocates have been known to expose what they see as detrimental "problems" in the WMAP data. One such problem is Richard Lieu's study{{ref|lieu}} of the ] of 31 clusters of galaxies being only one quarter of that predicted. While Lieu believes that this may represent a problem for ] models in the ], Lerner has claimed that the study is consistent with the plasma cosmology proposal of most of the CMB radiation originating closer to us than the clusters. Additionally, plasma cosmology advocates have claimed that the ] and ] ] of the CMB are oriented with slightly less radiation in the direction of the ]{{ref|quadoct}}, corresponding to a model where the ] filament would shield us from more distant filament CMB radiation. They have not, however, offered a detailed model predicting this phenomenon and critics observe that the alignment of the quadrupole and octopole is likely due to uncertainties in the removal of the foreground from the CMB: the quadrupole and octopole cannot be measured without some way of removing interference from the galactic plane from the all-sky map of the CMB. A careful analysis of the foregrounds indicates that there is little evidence for the alignment.{{ref|foreground}}
Since this theory hypothesizes filaments that efficiently scatter radiation longer than about 100 microns, it predicts that radiation longer than this from distant sources will be absorbed, or to be more precise, scattered, and thus will decrease more rapidly with distance than does radiation shorter than 100 microns. In the 1990’s such absorption or scattering was demonstrated by comparing radio and far-infrared radiation from galaxies at various distances--the more distant, the greater the absorption effect.{{ref|absscat}} This effect also explained the well-known fact that the number of radio sources decreased with increasing redshift more rapidly than the number of optical sources.

In 2004-2005 additional evidence supported the existence of some medium that scattered and re-emitted the CMB. Richard Lieu and colleagues presented a study{{ref|lieu}} of the ] of 31 clusters of galaxies. In this effect, CMB from behind the clusters is slightly "shadowed" by hot electrons in the clusters. Lieu showed that the effect for these clusters was at most one quarter of that predicted, strongly implying that most of the CMB radiation originated closer to us than the clusters, as predicted by the plasma model, but in sharp contradiction to the big bang model, which assumes that all the CMB originates at extreme distances.

Several observations have shown that the quadrupole and octopole ] of the CMB have a preferred orientation in the sky.{{ref|quadoct}} The quadrupole and octopole power is concentrated on a ring around the sky and are essentially zero along a preferred axis. The direction of this axis is in the direction toward the ] and roughly aligns with the axis of the ] filament of which our Galaxy is a part.

This observation conflicts with the big bang assumption that the CMB originated far from the local supercluster and is, on the largest scale, isotropic without a preferred direction in space. However, the new observations support the plasma explanation. If the density of the absorbing filaments follows the overall density of matter, as assumed by this theory, then the degree of absorption should be higher locally in the direction along the axis of the (roughly cylindrical) local supercluster and lower at right angles to this axis, where less high-density matter is encountered. This in turn means that concentrations of the filaments, which slightly enhance CMB power, will be more obscured in the direction along the supercluster axis and less obscured at right angle to this axis, as observed. Critics observe that the alignment of the quadrupole and octopole is likely due to uncertainties in the removal of the foreground from the CMB: the quadrupole and octopole cannot be measured without some way of removing interference from the galactic plane from the all-sky map of the CMB. A careful analysis of the foregrounds indicates that there is little evidence for the alignment.{{ref|foreground}}

Critics also point out that, unlike the big bang model, plasma cosmology has not yet calculated the full angular power spectrum of the cosmic microwave background and compared it to the WMAP data.{{ref|WMAP}}


===Redshifts=== ===Redshifts===
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] are a ubiquitous phenomenon that is summarized by the ] in which more distant galaxies have greater redshifts. Advocates of plasma cosmology dispute the claim that this observation indicates an expanding universe. ] are a ubiquitous phenomenon that is summarized by the ] in which more distant galaxies have greater redshifts. Advocates of plasma cosmology dispute the claim that this observation indicates an expanding universe.


⚫ However, attempts to offer a plasma-based explanation of the Hubble relation have also not been successful. While many plasma effects associated with ] of ] and ] or ] can give rise to frequency shifts, these effects tend to be too small and irregular to explain the Hubble relation, unless unrealistically high matter densities and isotropies of the plasma are assumed. Some plasma cosmology advocates, including Lerner, now believe that the Hubble relation may well be a result of unknown physical phenomena, such as the ].
In a 2005 paper, Lerner used recent data on high-redshift galaxies from the ] to test the predictions of the expanding-universe explanation of the Hubble relation. The big bang expanding universe predicts that surface brightness, brightness divided by apparent surface area, decreases as (z+1)<sup>-3</sup>, where ''z'' is redshift. More distant objects actually should appear bigger. But observations show that in fact the surface brightness of galaxies up to a redshift of 6 are constant, as predicted by a non-expanding universe and in sharp contradiction to the big bang. Efforts to explain this difference by evolution &ndash; early galaxies are different than those today &ndash; led to predictions of galaxies that are impossibly bright and dense.

⚫ However, attempts to offer a plasma-based explanation of the Hubble relation have also not been successful. While many plasma effects, such as the ], can give rise to frequency shifts, these effects tend to be too small to explain the Hubble relation, unless unrealistically high matter densities are assumed. Some plasma cosmologists, including Lerner, now believe that the Hubble relation may well be a result of new physical phenomena, like the ] postulated by ] in 1929, that causes light to lose energy as it travels. Many mechanisms, all involving in some way new physics, have been proposed to accomplish this. In theory, such phenomena could be observed with sufficiently sensitive equipment on earth, providing a definitive test as to the origin of the Hubble relation.


Critics contend that the expanding universe has been extensively confirmed by a suite of observations and is a clear prediction of Einstein's theory of ], a theory which has been precisely ] by a suite of different experiments. Critics contend that the expanding universe has been extensively confirmed by a suite of observations and is a clear prediction of Einstein's theory of ], a theory which has been precisely ] by a suite of different experiments. See also ].


===Future=== ===Future===
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* ] - Claims that the intergalactic medium is a strong absorber of the ] with the absorption occurring in narrow filaments. Postulates that ]s are not related to ]s but are rather produced by a ] self-compression process similar to that occurring in the ]. * ] - Claims that the intergalactic medium is a strong absorber of the ] with the absorption occurring in narrow filaments. Postulates that ]s are not related to ]s but are rather produced by a ] self-compression process similar to that occurring in the ].
* ] - Developed computer simulations of galaxy formation using Birkeland currents along with gravity. Along with Alfven, organized international conferences on Plasma Cosmology. * ] - Developed computer simulations of galaxy formation using Birkeland currents along with gravity. Along with Alfven, organized international conferences on Plasma Cosmology.
* ] - Developed the ] model.
* ] - Radio astronomer, writer of "''Interstellar matters : essays on curiosity and astronomical discovery''" and "''Cosmic catastrophes''". * ] - Radio astronomer, writer of "''Interstellar matters : essays on curiosity and astronomical discovery''" and "''Cosmic catastrophes''".


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#{{note|early}} H. Alfvén, ''Worlds-antiworlds: antimatter in cosmology,'' (Freeman, 1966). O. Klein, "Arguments concerning relativity and cosmology," ''Science'' '''171''' (1971), 339. #{{note|early}} H. Alfvén, ''Worlds-antiworlds: antimatter in cosmology,'' (Freeman, 1966). O. Klein, "Arguments concerning relativity and cosmology," ''Science'' '''171''' (1971), 339.
#{{note|Alf42}} Alfvén, Hannes, "On the cosmogony of the solar system", in ''Stockholms Observatoriums Annaler'' (1942) (, , ) #{{note|Alf42}} Alfvén, Hannes, "On the cosmogony of the solar system", in ''Stockholms Observatoriums Annaler'' (1942) (, , )
#{{note|spiral}} ] #{{note|spiral}}
#{{note|lensing}} There exists a considerable literature on using lensing to measure dark matter: . #{{note|lensing}} There exists a considerable literature on using lensing to measure dark matter: .
#{{note|Andromeda}} R. Ibata, S. Chapman, A. M. N. Ferguson, G. Lewis, M. Irwin, N. Tanvir, "On the accretion origin of a vast extended stellar disk around the Andromeda galaxy", . #{{note|Andromeda}} R. Ibata, S. Chapman, A. M. N. Ferguson, G. Lewis, M. Irwin, N. Tanvir, "On the accretion origin of a vast extended stellar disk around the Andromeda galaxy", .
#{{note|hzspect}} These surveys rely on the interpretation of redshifts in terms of Hubble's law. Because plasma cosmology has no model for redshift, this interpretation may not be applicable. #{{note|hzspect}} These surveys rely on the interpretation of redshifts in terms of Hubble's law. Because plasma cosmology has no model for redshift, this interpretation may not be applicable.
#{{note|fractal}} <!-- reference to fractal relationship for mass density needed-->
#{{note|nucleosynthesis}} E. J. Lerner, "On the problem of Big-bang nucleosynthesis", ''Astrophys. Space Sci.'' '''227''', 145-149 (1995). #{{note|nucleosynthesis}} E. J. Lerner, "On the problem of Big-bang nucleosynthesis", ''Astrophys. Space Sci.'' '''227''', 145-149 (1995).
#{{note|hecmb}} <!-- reference to energy released by Helium-4 formation -->
#{{note|cmb}} E. J. Lerner, "Intergalactic radio absorption and the COBE data", ''Astrophys. Space Sci.'' '''227''', 61-81 (1995). A. L. Peratt, "Plasma and the universe: Large-scale dynamics, filamentation, and radiation", ''Astrophys. Space Sci.'' '''227''', 97-107 (1995) <!-- Peter reference --> #{{note|cmb}} E. J. Lerner, "Intergalactic radio absorption and the COBE data", ''Astrophys. Space Sci.'' '''227''', 61-81 (1995). A. L. Peratt, "Plasma and the universe: Large-scale dynamics, filamentation, and radiation", ''Astrophys. Space Sci.'' '''227''', 97-107 (1995) <!-- Peter reference -->
#{{note|hn}} <!-- hoyle and narlikar reference -- is it the QSSO ref'n? -->
#{{note|absscat}} <!--reference to absorbtion from wavelengths longer than 100 microns-->
#{{note|lieu}} R. Lieu, J. P. D. Mittaz and S.-N. Zhang "Detailed WMAP/X-ray comparison of 31 randomly selected nearby clusters of galaxies - incomplete Sunyaev-Zel'dovich silhouette" #{{note|lieu}} R. Lieu, J. P. D. Mittaz and S.-N. Zhang "Detailed WMAP/X-ray comparison of 31 randomly selected nearby clusters of galaxies - incomplete Sunyaev-Zel'dovich silhouette"
#{{note|quadoct}} A. de Oliveira-Costa, M. Tegmark, M. Zaldarriga and A. Hamilton, "The significance of the largest scale CMB fluctuations in WMAP", ''Phys. Rev.'' '''D69''' (2004) 063516. D. J. Schwarz, G. D. Starkman, D. Huterer and C. J. Copi, "Is the low-''l'' microwave background cosmic?", ''Phys. Rev. Lett.'' '''93''' (2004) 221301. #{{note|quadoct}} A. de Oliveira-Costa, M. Tegmark, M. Zaldarriga and A. Hamilton, "The significance of the largest scale CMB fluctuations in WMAP", ''Phys. Rev.'' '''D69''' (2004) 063516. D. J. Schwarz, G. D. Starkman, D. Huterer and C. J. Copi, "Is the low-''l'' microwave background cosmic?", ''Phys. Rev. Lett.'' '''93''' (2004) 221301.
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==See also== ==See also==


* ''']''' : ], ] * ''']''' : ], ]s, ], ], ]
* ''']''' : ], ], ], ], ]s, ], ], ] * ''']''' : ], ], ], ],
* '''Other''': ], ] * '''Other''': ]
* The ] model, or the Alfvén-Klein model, is the original model of plasma cosmology. * The ] model, or the Alfvén-Klein model, is the original model of plasma cosmology.
* ''']''', a concept that includes elements of plasma cosmology but is much farther outside the mainstream.
* ''']''', which is a collection of outside the mainstream views on astrophysics that includes advocacy of plasma cosmology in addition to incorporating ] catastrophism and a non-standard model of stellar physics called the "Electric Star hypothesis." It does not appear to be taken seriously by most plasma cosmologists. It is not mentioned in the books, websites, or journal publications of Alfven, Peratt, Lerner, et al. (With one exception: On page 4 of his book ''The Big Bang Never Happened'', Lerner stated "hat I describe here is not... a Velikovskian fantasy." This may serve as an indicator as to how plasma cosmologists view Velikovskians.) Plasma cosmologists have likewise ignored the electric star model, and have always accepted the standard (fusion) theory.


==Links and references== ==Links and references==
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* Eastman, Timothy E., "''''". Plasmas International. (References, Parameters, and Research Centers links.) * Eastman, Timothy E., "''''". Plasmas International. (References, Parameters, and Research Centers links.)
* Goodman, J., "''''". * Goodman, J., "''''".
* Goodman, J., "''''"
*Heikkila, Walter J. "''''", from a ''''" Dedicated to Hannes Alfvén on 80th Birthday *Heikkila, Walter J. "''''", from a ''''" Dedicated to Hannes Alfvén on 80th Birthday
* IEEE Xplore, '''', '''18''' issue 1 (1990), Special Issue on Plasma Cosmology. * IEEE Xplore, '''', '''18''' issue 1 (1990), Special Issue on Plasma Cosmology.
* G. Arcidiacono, "Plasma physics and big-bang cosmology", ''Hadronic Journal'' '''18''', 306-318 (1995). * G. Arcidiacono, "Plasma physics and big-bang cosmology", ''Hadronic Journal'' '''18''', 306-318 (1995).
* J. E. Brandenburg, "A model cosmology based on gravity-electromagnetism unification", ''Astrophysics and Space Science'' '''227''', 133-144 (1995). * J. E. Brandenburg, "A model cosmology based on gravity-electromagnetism unification", ''Astrophysics and Space Science'' '''227''', 133-144 (1995).

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Plasma Universe and plasma cosmology. Hannes Alfvén urged the application of laboratory and magnetospheric data, and Anthony Peratt of large-scale particle-in-cell simulations, to non-in-situ space regions. Together with direct observation of interstellar and intergalactic plasma phenomenon, this leads them to predict a knowledge expansion about the universe, and a backflow of information about laboratory plasmas. (Click image to enlarge)

Plasma cosmology is a cosmological model based on the electromagnetic properties of astrophysical plasmas. Plasma cosmology explains the large scale structure and evolution of the universe, from galaxy formation to the cosmic microwave background by invoking electromagnetic phenomena associated with laboratory plasmas.

Plasma, electrically conducting gas in which electrons are stripped away from atoms and can move freely, makes up the stars and the interstellar medium. Astrophysicists agree that electromagnetic effects are important in stars, galactic discs, quasars and active galactic nuclei but in the standard big bang model the formation of structure is dominated by gravitational effects. Plasma cosmology asserts that the universe has no beginning, whereas in the big bang model the universe, as we know it, has existed for only a finite time. Plasma cosmology is considered by both opponents and supporters as a non-standard cosmology.

Overview

The basic assumptions of plasma cosmology are,

  1. since the universe is nearly all plasma, electromagnetic forces are equal in importance with gravitation on all scales.
  2. since we never see effects without causes, we have no reason to assume an origin in time for the universe—an effect without a cause. Thus this approach, in contrast to certain interpretations of the Big Bang cosmology, does not permit any beginning for the universe.
  3. unlike the steady state theory, the universe is not changeless. Rather, since every part of the universe we observe is evolving, it assumes that the universe itself is evolving as well.

Plasma cosmology also differs from big bang cosmology methodologically. Its advocates emphasize the links between physical processes observable in laboratories on Earth and those that govern the cosmos. Plasma cosmology is explained as much as possible in terms of known physics, using the theoretical and experimental results of laboratory plasma physics in cosmological applications. Proponents contrast this with the Big bang theory which has over the course of its existence required the introduction of such features as inflation, dark matter and dark energy that have not been detectable yet in laboratory experiments.

Plasma cosmology was first developed by Swedish physicist Hannes Alfvén in a book published in 1965. Alfvén is well-respected in the scientific community as the founder of modern plasma physics together with Oskar Klein, Per Carlqvist and Carl-Gunne Fälthammar. for which he received the Nobel Prize in Physics. While plasma cosmology has never had the support of large numbers of astronomers or physicists, a small group of plasma physicists such as Anthony Peratt and Eric Lerner have continued to promote and develop the approach. These physicists have been able to propose theories for the origin of large scale structure (such as quasars, galaxies, and clusters and superclusters of galaxies), for the synthesis of light elements, and for the origin of the cosmic microwave background. Although their theories are not generally accepted by the scientific community, proponents argue that they could explain observations more easily, without introducing the "new physics" seen in the big bang theory. Critics of the plasma cosmology point out that detailed observational testing of big bang cosmology is not rivalled by plasma cosmology and that the big bang theory is supported by multiple complementary quantitative tests.

Alfvén's model

File:Hannes-alfven-stamp.jpg
Hannes Alfvén (1908-1995), made significant advances in the study of plasmas and their application to physics and astronomy

Alfvén's model of plasma cosmology can be divided into three distinct areas.

  1. The cosmic plasma, an empirical description of the Universe based on the results from laboratory experiments on plasmas
  2. Force free filaments, a proposed mechanism for the formation of large scale structure in the universe.
  3. ambiplasma theory, based on a hypothetical matter/antimatter plasma.

Cosmic Plasma

Building on the work of Kristian Birkeland, Alfvén's research on plasma led him to develop the field of magnetohydrodynamics, a theory that mathematically models plasma as magnetic fluid, and for which he won the Nobel Prize for Physics in 1970. Magnetohydrodynamics is used by astrophysicists and astronomers to describe many celestial phenomena and is the core theory of modern fusion physics. However, Alfven pointed out that magnetohydrodynamics is an approximation which is accurate only in dense plasmas, like that of stars, where particles collide frequently. It is not valid in the much more dilute plasmas of the interstellar medium and intergalactic medium, where electrons and ions circle around magnetic field lines. Alfven devoted a large portion of his Nobel address to attacking this “pseudo plasma” error.

Alfvén felt that many other characteristics of plasmas played a more significant role in cosmic plasmas. These include:

Alfvén and his colleagues began to develop plasma cosmology in the 1960’s and 70’s as an extrapolation of their earlier highly successful theories of solar and solar-system phenomena. They pointed out those extremely similar phenomena existed in plasmas at all scales because of inherent scaling laws, ultimately derived from Maxwell's laws. One scale invariant in plasmas is velocity, so that plasmas at scales from the laboratory up to supercluster of galaxies exhibit similar phenomena in a range of velocities from tens to a thousand kilometers per second. In turn this invariance means that the duration of plasma phenomena scales as their size, so that galaxies a hundred thousand light years across with characteristic evolution times of billions of years scale to transient laboratory-scale phenomena lasting a microsecond.

While gravity becomes important at large scales, electromagnetic forces are rarely negligible and often dominate cosmic processes. Magnetic forces are particularly important since even in neutral plasma (like almost all astrophysical plasmas) magnetic forces have infinite range, like gravity. For example, in the Local Supercluster of galaxies, the magnetic field is at least 0.3 microgauss over a volume 10 Mpc in radius centered on the Milky Way, so here the magnetic field energy density exceeds the gravitational energy density by at least an order of magnitude.

Alfvén and his collaborators pointed to two plasma phenomena that have figured prominently in subsequent developments of plasma cosmology:

  1. The formation of force-free filaments. (See section below)
  2. The exploding double layer, where charge separation builds up in a current-carrying plasma, leading to the disruption of the current, the generation of high electric fields and the acceleration of energetic particles. This phenomenon, which was first observed in the laboratory, was suggested by Alfvén as a possible mechanism for the generation of cosmic rays.

Force free filaments

When currents move through any plasma, they create magnetic fields which in turn divert currents in such a way that parallel currents attract each other (the pinch effect). Plasma thus naturally becomes inhomogeneous, with currents and plasmas organizing themselves into force-free filaments, in which the currents move in the same direction as the magnetic field.

Such filaments act to pinch matter together in turn leads (for large enough filaments) to gravitational instabilities that cause clumps to form along the filaments like beads on a string. These gravitationally-bound clumps, spinning in the magnetic field of the filament, generate electric forces that create a new set of currents moving towards the center of the clump, as in a disk generator. This in turn creates a new set of spiral filaments that set the stage of the coalescence of smaller objects. A hierarchy of structure is thus formed.

The so-called magnetic braking in these filaments, as Alfvén and colleagues showed, may be important for the process of gravitational collapse, because they serve as a mechanism to transfer angular momentum from the contracting clump. Without a process to transfer angular momentum, the formation of galaxies and stars would be impossible as centrifugal forces would prevent contraction. Plasma cosmology advocates claim that such plasma processes can ultimately account for the large-scale structure of the universe and its filamentary organization of superclusters, clusters, galaxies, stars and planets. Subsequent to Alfven’s work, highly magnetized filaments were discovered at several scales in the cosmos, from parsec-scales at the center of the galaxy to supercluster filaments that stretch across hundreds of megaparsecs.

Ambiplasma

Main article: Ambiplasma

As theoretical considerations and experimental evidence from particle physics showed that matter and antimatter always come into existence in equal quantities, Alfvén and Klein in the early 1960s developed a theory of cosmological evolution based on the development of an "ambiplasma" consisting of equal quantities of matter and antimatter. Alfvén theorized that if an ambiplasma was affected by both gravitational and magnetic fields, as could be expected in large-scale regions of space, matter and antimatter would naturally separate from each other. When small matter clouds collided with small antimatter clouds, the annihilation reactions on their border would cause them to repel each other, but matter clouds colliding with matter clouds would merge, leading to increasingly large regions of the universe consisting of almost exclusively matter or antimatter. Eventually the regions would become so vast that the gamma rays produced by annihilation reactions at their borders would be almost unobservable.

This explanation of the dominance of matter in the local universe contrasts sharply with that proposed by big bang cosmology, which requires a asymmetric production of matter and antimatter at high energy. (If matter and antimatter had been produced in equal quantities in the extremely dense big bang, annihilation would have reduced the universal density to only a few trillionths of that observed.) Such asymmetric matter-antimatter production has never been observed in nature.

Alfvén and Klein then went on to use their ambiplasma theory to explain the Hubble relation between redshift and distance. They hypothesized that a very large region of the universe, consisting of parts alternately containing matter and antimatter, gravitationally collapsed until the matter and antimatter regions were forced together, liberating huge amounts of energy and leading to an explosion. At no point in this model, however, does the density of our part of the universe become very high. This explanation was appealing, because if we were at the center of the explosion we would observe the Doppler shifts from receding particles as redshifts, and the most distant particles would be the fastest moving, and hence have the largest redshift.

This explanation of the Hubble relationship did not withstand analysis, however. Carlqvist determined that there was no way that such a mechanism could lead to the very high redshifts, comparable to or greater than unity, that were observed. Moreover, it was difficult to see how the high degree of isotropy of the visible universe could be reproduced in this model. While Alfven’s separation process was sound, it seems almost impossible for the process to reverse and lead to a re-mixing of matter and antimatter.

Features and problems

In the past twenty-five years, plasma cosmology has expanded to develop models of the formation of large scale structure, quasars, the origin of the light elements, the cosmic microwave background and the redshift-distance relationship.

Formation of structure

In the early 1980’s Peratt, a former student of Alfvén’s, used supercomputer facilities at Maxwell Laboratories and later at Los Alamos National Laboratory to simulate Alfvén and Fälthammar’s concept of galaxies being formed by primordial clouds of plasma spinning in a magnetic filament. The simulation began with two spherical clouds of plasma trapped in parallel magnetic filaments, each carrying a current of around 10 amperes. In a video created from the simulation, the clouds begin to rotate around each other, spin on their own axes and distort their shape until a spiral shape emerges. Peratt claimed that the various stages in his simulation looked like observed galaxy shapes. Additionally, Perrat claimed that his model could explain the galaxy rotation problem without invoking dark matter.

The simulation did not contain gravitational forces, so even Perrat admitted it wasn't wholly realistic. Current galaxy formation models rely on so-called hierarchical structure formation that is theoretically derivable from the power spectrum of anisotropies seen in the cosmic microwave background. The mass estimates of galaxy clusters using gravitational lensing, which is an independent check from the rotation curves, also indicate that there is a large quantity of dark matter present independent of the measurements of galaxy rotation curves, causing the vast majority of astrophysicists to accept dark matter as a real phenomenon that cannot be explained by appeal to electromagnetic processes.

In the mid-80’s Lerner used plasma filamentation theory to develop a general explanation of the large scale structure of the universe. Lerner claims that plasma cosmology can easily accommodate large scale structures and he predicts a fractal distribution of matter with density being inversely proportional to the distance of separation of objects. Plasma filamentation theory allows the mass of condensed objects formed to be predicted as a function of density. Magnetically confined filaments initially compress plasma, which is then condensed gravitationally into a fractal distribution of matter. However, critics of plasma cosmology argue that a fractal distribution seems to be ruled out by measurements of the large scale matter power spectrum, such as the Sloan Digital Sky Survey, which indicate a nearly scale-invariant Harrison-Zel'dovich spectrum, rather than a fractal spectrum.

Light elements abundance

Eric Lerner calculated the size of stars assuming Perrat's formation model and thus the amounts of helium and other light elements. This led to the predictions that large numbers of intermediate mass stars (from 4-12 solar masses) would be generated during the formations of galaxies. Lerner claimed that his model for nucleosynthesis led to a broader range of predicted abundances than Big Bang nucleosynthesis, because the plasma theory hypothesizes a process occurring in individual galaxies, so some variation is to be expected. In addition cosmic rays are postulated to produce – by collisions with ambient hydrogen and helium – the observed amounts of deuterium and various isotopes of lithium.

Microwave background

According to Big Bang nucleosynthesis the amount of energy released in producing the observed amount of helium-4 is the same as the amount of energy in the cosmic microwave background (CMB) since the photons and the baryons were coupled during the production of nuclei. Plasma cosmology advocates claim that this correspondence, rather than being due to energetic photons driving universal nucleosynthesis, is explained by the stellar nucleosynthesis of helium releasing the required CMB energy from the stars in the early stages of the plasma cosmology's version of formation of galaxies. In order for such a model to yield the near-perfect observed blackbody spectrum, Lerner, Peratt and others hypothesized that the energy is thermalized and isotropized by a thicket of dense, magnetically confined plasma filaments that pervade the intergalactic medium. Lerner developed this model, by matching the isotropic and homogeneous blackbody spectrum of the CMB using a fraction of the data set from COBE. Critics have pointed out that, unlike the big bang model, plasma cosmology has not calculated the full detail angular power spectrum they would expect from their cosmic microwave background and compared it to the WMAP data.

Since the WMAP observations have been touted by many in the scientific mainstream as a "confirmation" of the Big Bang, plasma cosmology advocates have been known to expose what they see as detrimental "problems" in the WMAP data. One such problem is Richard Lieu's study of the Sunyaev-Zel’dovich effect of 31 clusters of galaxies being only one quarter of that predicted. While Lieu believes that this may represent a problem for baryogenesis models in the Lambda-CDM, Lerner has claimed that the study is consistent with the plasma cosmology proposal of most of the CMB radiation originating closer to us than the clusters. Additionally, plasma cosmology advocates have claimed that the quadrupole and octopole moments of the CMB are oriented with slightly less radiation in the direction of the Virgo cluster, corresponding to a model where the Local Supercluster filament would shield us from more distant filament CMB radiation. They have not, however, offered a detailed model predicting this phenomenon and critics observe that the alignment of the quadrupole and octopole is likely due to uncertainties in the removal of the foreground from the CMB: the quadrupole and octopole cannot be measured without some way of removing interference from the galactic plane from the all-sky map of the CMB. A careful analysis of the foregrounds indicates that there is little evidence for the alignment.

Redshifts

Cosmological redshifts are a ubiquitous phenomenon that is summarized by the Hubble Law in which more distant galaxies have greater redshifts. Advocates of plasma cosmology dispute the claim that this observation indicates an expanding universe.

However, attempts to offer a plasma-based explanation of the Hubble relation have also not been successful. While many plasma effects associated with scattering of photons and ions or electrons can give rise to frequency shifts, these effects tend to be too small and irregular to explain the Hubble relation, unless unrealistically high matter densities and isotropies of the plasma are assumed. Some plasma cosmology advocates, including Lerner, now believe that the Hubble relation may well be a result of unknown physical phenomena, such as the tired light effect.

Critics contend that the expanding universe has been extensively confirmed by a suite of observations and is a clear prediction of Einstein's theory of general relativity, a theory which has been precisely tested by a suite of different experiments. See also cosmological constant.

Future

Plasma cosmology is not a widely-accepted scientific theory, and even its advocates agree the explanations provided are less detailed than those of conventional cosmology. Its development has been hampered, as have that of other alternatives to big bang cosmology, by the exclusive allocation of government funding to conventional cosmology. Most of these conventional cosmologists argue that this bias is due to the large amount of detailed observational evidence that validates the simple, six parameter ΛCDM model of the big bang.

Figures in plasma cosmology

The following physicists and astronomers helped, either directly or indirectly, to develop this field:

  • Hannes Alfvén - Along with Birkeland, fathered Plasma Cosmology and was a pioneer in laboratory based plasma physics. Received the only Nobel Prize ever awarded to a plasma physicist.
  • Kristian Birkeland - First suggested that polar electric currents are connected to a system of filaments (now called "Birkeland Currents") that flowed along geomagnetic field lines into and away from the polar region. Suggested that space is not a vacuum but is instead filled with plasma. Pioneered the technique of "laboratory astrophysics", which became directly responsible for our present understanding of the aurora.
  • Eric Lerner - Claims that the intergalactic medium is a strong absorber of the cosmic microwave background radiation with the absorption occurring in narrow filaments. Postulates that quasars are not related to black holes but are rather produced by a magnetic self-compression process similar to that occurring in the plasma focus.
  • Anthony Peratt - Developed computer simulations of galaxy formation using Birkeland currents along with gravity. Along with Alfven, organized international conferences on Plasma Cosmology.
  • Gerrit L. Verschuur - Radio astronomer, writer of "Interstellar matters : essays on curiosity and astronomical discovery" and "Cosmic catastrophes".

Footnotes

  1. 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 – 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 ,.
  2. H. Alfvén, Worlds-antiworlds: antimatter in cosmology, (Freeman, 1966). O. Klein, "Arguments concerning relativity and cosmology," Science 171 (1971), 339.
  3. Alfvén, Hannes, "On the cosmogony of the solar system", in Stockholms Observatoriums Annaler (1942) (Part I, Part II, Part III)
  4. Galaxy anatomy
  5. There exists a considerable literature on using lensing to measure dark matter: spires.
  6. R. Ibata, S. Chapman, A. M. N. Ferguson, G. Lewis, M. Irwin, N. Tanvir, "On the accretion origin of a vast extended stellar disk around the Andromeda galaxy", arXiv:astro-ph/0504164.
  7. These surveys rely on the interpretation of redshifts in terms of Hubble's law. Because plasma cosmology has no model for redshift, this interpretation may not be applicable.
  8. E. J. Lerner, "On the problem of Big-bang nucleosynthesis", Astrophys. Space Sci. 227, 145-149 (1995).
  9. E. J. Lerner, "Intergalactic radio absorption and the COBE data", Astrophys. Space Sci. 227, 61-81 (1995). A. L. Peratt, "Plasma and the universe: Large-scale dynamics, filamentation, and radiation", Astrophys. Space Sci. 227, 97-107 (1995)
  10. R. Lieu, J. P. D. Mittaz and S.-N. Zhang "Detailed WMAP/X-ray comparison of 31 randomly selected nearby clusters of galaxies - incomplete Sunyaev-Zel'dovich silhouette" astro-ph/0510160
  11. A. de Oliveira-Costa, M. Tegmark, M. Zaldarriga and A. Hamilton, "The significance of the largest scale CMB fluctuations in WMAP", Phys. Rev. D69 (2004) 063516. D. J. Schwarz, G. D. Starkman, D. Huterer and C. J. Copi, "Is the low-l microwave background cosmic?", Phys. Rev. Lett. 93 (2004) 221301.
  12. A. Slosar and U. Seljak, "Assessing the effects of foregrounds and sky removal in WMAP", Phys. Rev. D70, 083002 (2004). astro-ph/0404567
  13. 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.

See also

Links and references

Books

  • H. Alfvén, Worlds-antiworlds: antimatter in cosmology, (Freeman, 1966).
  • H. Alfvén, Cosmic Plasma (Reidel, 1981) ISBN 9027711518
  • E. J. Lerner, The Big Bang Never Happened, (Vintage, 1992) ISBN 067974049X
  • A. L. Peratt, Physics of the Plasma Universe, (Springer, 1992) ISBN 0387975756
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