FRED ANSWERS YOUR QUESTIONS

If, as current thought dictates, the Universe began as a grape-sized ‘singularity’, where did the matter and energy for 2 trillion galaxies, each of 100 billion stars, come from? Did the Universe: create itself as it expanded; sweep up matter already nearby; or was it all once squeezed into a grape-sized area? Doug Hurst, Chapman, ACT The last alternative is what’s usually accepted. By definition, space and time don’t exist within a singularity that has infinite density, meaning the energy of the initial singularity is unknown. Observations of the

Big Bang ‘flash’ (see this column in AG 146) tell us the Universe was extremely hot and dense shortly after forming. We can thus extrapolate back in time, providing the best observational evidence for the initial singularity’s extreme energy.