The Physics Department were delighted to welcome the Physics Nobel Laureate, Prof Brian Schmidt AC FAA FRS FTSE, Distinguished Professor of Astronomy at the Australian National University on April 14th and 15th. Prof Schmidt was visiting Maynooth University to give the Dean's Lecture 2025 (Faculty of Science and Engineering) ‘The Universe from Beginning to End’ on Monday night in the TSI L1 lecture room. The audience were entertained and amazed by Prof Schmidt’s explanation of the science behind his Nobel Prize in Physics in 2011 using supernova explosions to detect the presence of dark energy in the Universe.
After years of observations, the High-Z Supernovae Search Team led by Prof Schmidt came to the conclusion that the cosmic expansion of the Universe is actually accelerating and not slowing under the influence of gravity as might be expected. By studying type Ia supernova where they found that the light from over 50 distant supernovae was weaker than expected. This was a sign that the expansion of the universe was accelerating. In order to account for the acceleration, about 75% of the mass-energy content of the Universe had to be made up of some gravitationally repulsive substance that nobody had ever seen before. This substance, which would determine the fate of the universe, was named dark energy.
It is now thought that dark energy constitutes around 75% of the current universe, with around 21% being dark matter and the rest ordinary matter and energy making up the Earth, planets and stars (and you!).
