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Science and the Bible
- 1 Cosmology
Appendix 2:
A brief history of the cosmos.
Telescopes - such as the Hubble telescope - show we are surrounded by millions of
galaxies. Observation shows that overall movement of the galaxies is to move away
from each other. The speed of any two galaxies is greater the further they are apart.
This is understood to be the result of space expanding.
Working backwards in time it is thought that all the matter of which the present
galaxies are formed must have come into existence as a single point – the “Big Bang”
– approximately 15 billion (15,000,000,000) years ago. (There are other possibilities –
but this is the standard model – which most cosmologists consider to be the best
theory on present evidence.)
From the theory of relativity space and time are defined by the matter in it – so at the
“big bang” space and time came into existence with the total matter of the universe
confined to a single point1. The matter began at an infinitely high temperature and
began to cool as the space-time it defined expanded.
For a very short time (10-43 s) after the “big bang” space was so small that there is no
accepted theory which describes what was happening. (But beware of “God of the
gaps”!) Thereafter the processes of the next 300,000 years – in which hydrogen and
helium were formed – are fairly well understood in terms of particle physics.
14 billion years ago the first stars were formed. 12 - 10 billion years ago stars began
to group in galaxies.
The processes that cause stars to shine and by which all other elements were formed
from the primordial hydrogen and helium is well understood in terms of nuclear
physics.2 New stars formed incorporating all elements from the debris of earlier
exploded stars.
Our Sun, a third generation star, was formed nearly 5 billion years ago and the Earth
formed soon after.
The first life on Earth appeared nearly 4 billion years ago.
Homo sapiens appeared about 0.2 billion years ago.
Science is a process of building “stories” (i.e. “Theories”) which account for as much observational
data as possible. In sciences such as cosmology theories contain a considerable mathematical element
and it is often difficult – if not impossible! - to visualise the outcome of a mathematical process.
1
Carbon and the other elements from which our bodies are built were produced in the dying – supernova - explosions of large stars. We are, as is often said, “stardust”.
2
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16/06/2009