Cosmology after Hawking by Prof Steve Eales
Tue 13th Nov
President’s Invitation Lecture / Darlith Wahodd y Llywydd
Cosmology after Hawking / Cosmoleg ar ôl Hawking
Prof Steve Eales (Cardiff University) / Yr Athro Steve Eales (Prifysgol Caerdydd)
RISW President's Invitation Lecture: 'Cosmology after Hawking'
Prof. Steve Eales 13th November 2018
Professor Steve Eales, Head of Astronomy at Cardiff University gave his time most generously to do what some might deem ‘undoable’: to deliver a lecture on a highly specialist subject to a non-specialist public audience.
Yet around 70 people from different academic backgrounds and of widely differing ages sat captivated throughout, many questions showing that interest had been easily maintained and minds filled with questions by the end.
We are grateful to Professor Eales for his excellent, thought- provoking, lively lecture and for kindly sharing his entertaining and informative presentation slides with us - a link to which can be accessed on the RISW website.
‘People won’t have time for you if you are always angry or complaining…’
Beginning with this quote from Stephen Hawking and a clarification between being an observational scientist, as Prof Eales explained he is, and a theoretician, as he explained Stephen Hawking was, the lecture then led us through:
- the accidental discovery in the 1960s of Cosmic Microwave Background Radiation by radio astronomers Robert Wilson and Arno Penzias
- recognition that the radio ‘noise’ discovered is the accumulated radiation from all around the universe from 400,000 years after the Big Bang
- the phenomenon of ’looking back in time’ when looking at the stars. This is because of the actual time is takes to travel from first emission in the past until reaching our eyes in the present. We are only observing them as they were millions of years ago. (The sun is seen as it was 8 minutes ago.)
- brightness as an indicator of the density of matter implying that the early universe was very homogeneous 400,000 years after the Big Bang although now it is much less so, which Professor Eales described as the Universe now being ‘lumpy’, shaped by the force of gravity
- the big questions being asked in the 1990s: Is the Universe going to expand forever? Did inflation really happen?
- Three Cosmological Parameters (the first explained as determining whether the Universe will collapse or expand forever)
- Dark energy constituting 68.3 % of the Universe – not understood in terms of what it is but rather its effect on the Universe causing it to decelerate; gravitational lensing being used to investigate dark energy
- Dark matter accounting for 26.8% of the Universe
- Ordinary Matter being 4.9 % of the Universe
- EUCLID, the European satellite to measure the gravitational lensing of galaxies at different times in the past to allow us to investigate the properties of Dark Energy
- The reason for not being able to see beyond 400,000 years from the Big Bang being that the Universe was so hot all the matter was ionised (split into protons and electrons) and thus opaque
- Gravitational waves detected in 2016 as ripples in space time
…amongst much more.
Professor Eales ended with another perspective from Stephen Hawking on human beings:
‘We are just a slightly advanced breed of monkeys on a minor
planet orbiting an average star. But we can understand the
universe, and that makes us something very special.’
Successfully sharing his knowledge of Astronomy with the general public, Professor Eales is author of, ‘Origins - How the Planets, Stars, Galaxies, and the Universe Began’.
Our heartfelt thanks to Professor Eales for such a refreshing and enriching evening’s learning - fortunately delivered for our enjoyment, without the examination pressure students so often feel.
Tuesday 13 November / Mawrth 13 Tachwedd 7:00pm
Held in the Faraday Lecture Theatre, Singleton Campus, Swansea University
Cynhelir yn Narlithfa Faraday, Campws Singleton, Prifysgol Abertawe