Origins of the universe Flashcards
What is redshift?
When different galaxies absorb different frequencies of light, but we can see some are shifted towards the red end of the spectrum
What does redshift show us?
The more redshift, the further away a galaxy is, meaning they are moving faster
What is the doppler effect?
When something is moving towards you its frequency will seem higher and its wavelength shorter, and when something is moving away from you its frequency will seem lower and its wavelength longer
What type of wave does the doppler effect apply to?
Both longitudinal and transverse
How did the universe begin?
The big bang, which was when the matter in the universe was compressed into a very small space, then exploded, and started expanding
How can we guess the universe’s age?
By looking at the rate of expansion, as the universe is still expanding
What is the steady state theory?
That the universe has always been and always will be
What is Cosmic microwave background radiation?
A low frequency radiation coming from all parts of the universe, that is currently in the microwave part of the EM spectrum
What caused CMBR?
After the big bang, the universe emitted high frequency radiation, and as it expanded, it cooled, dropping the frequency of the radiation, making it microwave radiation
What is evidence for the big bang theory?
Redshift and CMBR
What are the problems with the big bang theory?
The big bang theory actually suggests that the universe’s expansion should be slowing down not speeding up, and it doesn’t explain why the matter was there in the first place or why conditions were like that
