SP5e Origin of the universe Flashcards
What does the steady state theory suggest?
that the universe is expanding but new matter is continually being created, so the universe will always appear the same (propsed by Hermann Bondi and Fred Hoyle)
What does the big bang theory suggest?
that the whole universe and matter started out as a tiny point of concentrated energy, around 13.8 billion years ago and has been expanding ever since (proposed by Father Georges Lemaitre)
Describe the evidence supporting the big bang theory; expanding universe.
as light travels through the expanding space it is stretched towards the red end of the spectrum, and this implies a starting point – a singularity.
Describe the evidence supporting the big bang theory; cosmic microwave background radiation (CMBR).
the even distribution through space, of radiation from the big bang that has cooled and stretched.
Describe the evidence supporting the big bang theory; abundance of light elements.
the simple elements would have formed first and exist in much greater quantities than the heavier elements created in stars and supernovae.
Explain how both theories of the origin of the universe account for red shift.
Both theories suggest that the universe is expanding and red shift observations show that the further a galaxy is away from us the faster it is moving. This shows that billions of years ago the galaxies were all much closer together but they have expanded.
How did the discovery of the CMBR led to the big bang theory becoming the currently accepted model?
The serendipitous discovery of the CMB put the SS/BB debate to rest by confirming that the universe began in a hot, dense state and it could not be explained by the Steady State model.
