A physicist programs two simulations, one based on the Big Bang theory and one based on the Steady State theory. Each simulation starts with the same positions for a group of widely separated galaxies and runs forwards for a short time.
Which change should occur in the Steady State simulation but not in the Big Bang simulation?
The galaxies move back into one hot, dense region.
The distances between the galaxies increase.
The average density of the Universe decreases.
New matter forms in the spaces between the galaxies.
94 exam-style questions on Edexcel GCSE Physics 7.2 The Universe and red-shift, covering 7.2.1 Big Bang and Steady State theories, 7.2.2 Evidence for the Big Bang, 7.2.3 The Doppler effect and red-shift, 7.2.4 Red-shift as evidence for an expanding Universe, and 7.2.5 The CMB and the accepted model. Each one has a worked solution and a mark scheme showing where the marks go.