Foundations of Modern Cosmology

© 2000 by Robert C. Moler

For much of history the cultures of the east, especially China, led the way over the west in technology, such as gun powder, rockets, and mathematics such as the concept of zero. However science and the scientific method took hold in the west, and with it came applied science or technology that has advanced at an exponential rate. With it, so have our ideas of the nature of the universe in which we live, or cosmology. Is the difference between the religions of east and west the cause? I think so.

Before going on, let's define cosmology. Cosmology is the study of the universe as an ordered system. Therefore one might thing that astronomy is part of cosmology, are that cosmology is itself part of astronomy.

Astronomy, as a science came first, but cosmology as religious concepts predates any science. Thus we see in our day a tension between religion and science with its current ideas of cosmology, and particularly cosmogony, the study of the origin of the universe. Yet, it seems that the ideas from the Hebrew scriptures combined with the world view of the Greek philosophers, that was accepted by the early Christian church, provided fertile ground for the development of scientific advancement that gave rise to our current view of cosmology.

The cosmological ideas of the Bible and the Greek philosophers are no longer viable science. That is not the point. I wonder how our cosmology will fare 2,000 years hence. If we are lucky, we now have the barest of outlines of what will be known in the future. If not, our cosmology is merely one more dead end.

Let's stop and talk a bit about what we know, or think we know about cosmology or the nature of the universe. We start with a principle, not a fact, but an assumption, called the Cosmological Principle: That the universe looks, in general the same as viewed form any point with in it. That is, there is no privileged position, no center and no edge. What do we know? It seems that the physical laws are the same everywhere. Spectrographs record the fingerprints of hydrogen and the other elements known on earth, from the farthest galaxies. Plus we know from Edwin Hubble's observations of the early 20th century, that the universe is not static, but expanding.

That expansion gives rise to the cosmogony of the Big Bang, the origin of the universe in one split second act of creation, perhaps 15 billion years ago, or possibly as recent as 8 billion years ago.

The cosmology of the 20th century rests on two great and sometimes mutually contradictory theories: Relativity and the Quantum Mechanics. It also rests on the four known fundamental forces. The strong and weak nuclear forces bind the nuclei of atoms. The electromagnetic force binds electrons in orbit of atomic nuclei, and works all our marvelous electronic devices. However the net electrical charge of the universe is zero. Weakest of all forces is gravity. As far as we know, gravitational force is always attractive. Given a great enough mass, its gravitational warping of space-time can overwhelm the nuclear forces and actually pinch itself off from the rest of the universe in a black hole

How did we get from the simple universe of the Greeks and Hebrews to our current state of knowledge?

The Hebrew Bible which the west inherited speaks of one God, the law giver, not a pantheistic menagerie of gods who each ruled capriciously over an aspect to nature. The Greek philosophers, even though living an a society that paid lip service to their pantheistic religion, came to the conclusion that there were immutable natural laws.

The intellectuals in the west, then came to believe that not only there were natural laws, but they could be described mathematically, and tested. From f=ma of Isaac Newton to e=mc2 of Albert Einstein, we have found that we can make sense of the laws of nature. Thus fortified we have dared to ponder the nature and origin of the universe itself.


Questions? Send Email to me at bob@bjmoler.org

Updated: 01/01/01