An Alternative Approach to Cosmogony and Cosmology
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J. Astrophys. Astr. (1997) 18, 349-351 An Alternative Approach to Cosmogony and Cosmology G. Burbidge, University of California, San Diego, Center for Astrophysics & Space Sciences, and Department of Physics, La Jolla, CA 92093-0424 USA Abstract. Some problems associated with the big bang cosmological model are briefly discussed. It is shown that the quasi-steady state model (QSSC) is a viable alternative. Moreover, the cosmogony related to this theory is supported by the observations. Key words. Cosmology—cosmogony—relativistic jets—quasi-stellar- objects. Most meetings, symposia, and workshops on cosmology are, in this era, devoted to discussions of data interpreted in terms of the Friedmann models and more speci- fically the hot big bang. This meeting in Bangalore is different in the sense that at least one alternative cosmological model, the quasi-steady state cosmological model (QSSC), is under discussion. For a theory to be viable, it must be able to explain at least some of the known phenomena, and it must be testable in the sense that with it predictions can be made that can be tested with future observations. Two of the speakers today are Dr. Arp and Dr. Narlikar. Dr. Arp has discussed some of the observations which we believe support the cosmogony closely related to the QSSC. Dr. Narlikar is discussing the QSSC theory. It is only left for me to put the arguments and ideas into a logical and believable framework. As you are all aware, the hot big bang cosmology rests on the framework of the Friedmann models which are developed from Einstein’s general theory of relativity. With this theory the expansion is naturally explained, the very light isotopes, D, He3, He4 are understood as being made in the first few minutes of the big bang, and the black body nature of the microwave background is seen as a prediction of the theory. These are the main pillars on which the theory rests. Because of some difficulties associated with the physics of the early universe, and the relationship to observations, it has been necessary to complicate the simple picture by (1) invoking inflation which is a very attractive idea, but which cannot be tested in any fundamental way, and (2) to argue that most of the mass-energy in the universe is in the form of non-baryonic matter for which there is no observational evidence at all. To be honest, some leading big-bang enthusiasts are prepared to do without non-baryonic matter and even (who knows) inflation. To make galaxies density fluctuations have to be invoked; there is no theory for this and people now talk of quantum fluctuations or cosmic strings or whatever. But this is not theory – it is speculation which is required because galaxies do exist. All cosmological theories invoke the creation of mass energy. The only difference between the big bang and the steady state in this connection is that in the first case creation is a single event which cannot be understood within the framework 349 350 G. Burbidge of the laws of physics, while creation in many events in regions of very strong gravitational fields in the centers of galaxies which is invoked in QSSC can be understood in terms of the Hoyle-Narlikar C-field theory which contains a modifica- tion of Einstein’s theory. Since Arp and Narlikar are covering many aspects of the new ideas, I only need to make a few remarks about the relationship of the QSSC cosmology to the cosmogony which is indicated by the observations. The general view concerning the origin of galaxies and more compact objects has been that they are formed by gravitational instability and collapse of clouds of gas and dust at very low density i.e. the progression is in the opposite sense to the expansion. It is not surprising therefore, that it has always been hard to understand how collapse and accretion can take place in such an environment. And as was shown many years ago, it is not possible for normal density fluctuations to do this. It is for this reason that initial density fluctuations are assumed to be present in an early universe in the big bang model. Of course, the underlying reason is that it is always assumed that gravity is the only effective force. In some theories of galaxy formation and evolution it is supposed that massive black holes are present early on and are important in the evolution. This presupposes that in some mysterious way massive black holes formed early in the history of the universe. But there is no theory of this either. The New Cosmogony In the 1950s Ambartsumian proposed that many groups and clusters of galaxies should be interpreted as expanding associations with positive total energy. He argued that they must all have expanded from a superdense state (presumably in the center of a parent system). It was already clear that if one supposed that the clusters were bound and stable and the virial theorem could be used, since the kinetic energy of the visible matter is much greater than the potential energy of the same matter (2KE + PE > 0) there must be a great deal of dark matter present to stabilize the clusters. That the clusters are old (~ 1010 years) and stable is the current popular belief, and it is that assumption that leads to the evidence for the existence of dark matter in multiple systems. –1 If Ambartsumian’s ideas are correct, then many galaxies have ages ≪ H0 . Led by Jan Oort and other great men this hypothesis has been generally ignored. Also in the 1950s the powerful radio sources were identified, and it became clear that they were due to very violent events in which large amounts of energy in the form of relativistic particles and magnetic flux are ejected from the nuclei of galaxies. They are indeed “little big bangs”. The current paradigm is that all of the energy output in violent events in radio galaxies, in Seyfert galaxies and in QSOs, is gravitational energy released by matter falling into massive black holes at the centers of galaxies. For the compact non-thermal sources – QSOs, Seyfert nuclei, etc. it is argued that <~ 10% of the rest mass energy of the matter falling into the black hole from the accretion disk is responsible. For the extended sources, and the rapidly variable sources where the non-thermal energy is dominant, it is argued that energy is carried out by highly relativistic jets with the energy originally being released from gravitational collapse involving a rotating black hole. An Alternative Approach to Cosmogony and Cosmology 351 While dark masses in the range 106–108M have been detected in a number of ⊙ nearby galaxies of which M87 is the only active one, there is no direct evidence in any case for an accretion disk with a realistic size, nor can there be in the 8 foreseeable future, since for a mass of 10 M ⊙ a radius of 1000 Schwarzschild radii would only subtend an angle of 30 microarc seconds at the distance of the Virgo cluster. What we always see in active galaxies is energy in the form of hot gas, relativistic particles, and coherent objects (cf paper by Arp) being ejected but nothing falling in. Even in the much advertised case of NGC 4258 (Miyoshi et al. 1995) the evidence for a black hole and accretion disk is ambiguous (cf. Burbidge & Burbidge 1997). Also from an energetic standpoint, the overall efficiency of production of energy in the large extended lobes in radio galaxies is very low, and this renders the black hole paradigm unworkable since in our opinion the mass required is too large. Thus our conclusion is that all of the observations made since the 1960s of violent events and expanding associations suggest that Ambartsumian was correct, and that they all show that ejection is the dominant mode and this is how new matter and energy, sometimes in the form of compact objects – galaxies and QSOs, is born. This is the cosmogony of little big bangs in which energy is created in regions of very strong gravitational fields in already existing systems. This cosmogony is directly compatible with the quasi-steady state cosmology (QSSC). As Dr. Narlikar will show, in this theory the inclusion of the C field shows that matter can be created in the regions with very strong gravitational fields in the centers of galaxies. In this scheme the universe is steadily expanding on a time scale ~ 1012 years with cyclic oscillations involving maximum and minimum periods of compression and rarefaction, with activity in galactic nuclei being greatest in the periods of compression. The QSSC can explain all of the classical cosmological parameters – the expansion, the abundances of the light isotopes and the microwave background. In addition, it explains what we see in the explosive cosmogony. References Burbidge, E. M., Burbidge, R. 1997, Astrophys. J. Lett., L13, 477. Miyoshi, M., Moran, J., Herrnstein, J., Greenhill, L., Nakai, N., Diamond, P., Inoue, M. 1995, Nature, 373, 127. .