Where Do We Go From Here ? (Cosmology, The Nature of The Universe)
Cosmology has changed from a subject of philosophical and theo¬logical introspection into a branch of the physical sciences. There is now an established framework which delineates the arena of cosmic physics. It is not thought that future developments will change the basic picture, but will rather define the picture more precisely. Thus we expect to be able to describe the Universe in greater detail in future, as a result of further observations and advances in theoretical physics.
On the observational side, there are prospects for mapping out the expansion law of the Universe in greater detail, and for study¬ing the spectrum and distribution of the cosmic background radiation. The number of galaxies with measured redshifts and magnitudes is only in the thousands, but we do not understand galaxies well enough to utilize even that much data. It is to be expected that this quantity of data will increase significantly owing to the development of automatic photographic-plate measuring machines and the building of large telescopes and specialized peripheral equipment for them. With an increased knowledge of the properties of galaxies, the prospects indeed look bright for achieving such goals as characterizing the clustering of galaxies and determining the Bubble law. Just as the discovery of the cosmic background radiation field engendered a renaissance in cosmology, the detailed study of all aspects of the radiation will provide us with direct information about the Universe at the early times when the radiation spectrum was established.
On the theoretical level, there is little doubt that the success of the nucleosynthesis arguments in constraining the number of possible cosmological models will be thoroughly exploited. Much of that work will be based on models for stellar and galactic evolution. Theoretical work, combined with observational data will tell us about the origin of galaxies, and this will in turn, via our models for galaxy formation, tell us about the Universe. The development of high-speed, super-computers will enable cosmologists to simulate various aspects of cosmology, such as the growth of clustering of galaxies and the evolution of galaxies. At a deeper level there is now a realistic and exciting prospect of forging a link between the microscopic world of elementary particle physics and the theory of gravitation.