The Big Bang
What is the big bang?
The theory of how the universe started off
Who proved that the universe was expanding?
Hubble
Did we have both energy and matter at the start of the universe?
Only energy
What are the 4 sections of the HR diagram, name them.
Main sequence, super giant, giants
The early stages - when they are 'new born'
How did the Big Bang occur?
It occurred because of the high-energy singularity in the origin of the universe which was extremely hot and dense so it expanded.
What supported the expansion of the universe?
The distant galaxies
What process transforms matter to energy?
Annihilation. A reaction in which a particle and its antiparticle collide and disappear, releasing energy
What is in the x-axis, and y-axis of the HR diagram?
Wavelength, and luminosity
What processes account for the production of energy in stars?
Proton-Proton chains and CNO cycles
What nuclear process formed stars?
Fusion
How did Hubble prove that the universe was expanding?
He observed that spectral lines of stars were red-shifted (so moving away from Earth) hence he suggested the universe must be expanding
When were elementary particles formed?
They were formed in the first microsecond
What are the spectral types in the HR diagram?
OBAFGKM
What process is most common in the main sequence of stars?
Proton-proton chain
Did cosmic inflation occur before or after the Big Bang?
Before
Name the four models of how the universe could be evolving.
Static, open, closed, flat
What were the fundamental particles formed in the Big bang?
Quarks and Leptons, along with their antiparticles
What spectral type of stars is the hottest?
Spectral class "O" with temperature > 30000K
When stars ‘die’ what do they turn into (there are multiple answers)?
White Dwarfs, black hole or a supernova
When did the Big Bang theory propose the universe began?
13.8 billion years ago
What is the hubble formula?
V = H_o*D where Ho is Hubble's constant and D is distance away from us
What was created after 3 minutes of the Big Bang?
Hadrons, including mesons, protons and neutrons, were produced, along with their antiparticles
What is the main sequence?
Transition into a main-sequence star once the fusion of hydrogen begins in a protostar’s core produces helium which settles to the centre of the star because it is denser than hydrogen
How do stars die?
Stars die as white dwarfs when they run out of helium and lose a ton of their mass.