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Hamilton Lecture 2020: The Cosmic Distance Ladder


Friday, October 16, 2020, 16:00


Free online event


Free online event: booking is essential

Join us online to watch Professor Terence Tao of University of California, Los Angeles deliver the Hamilton Lecture 2020.

The Cosmic Distance Ladder

How do we know the distances from the earth to the sun and moon, from the sun to the other planets, and from the sun to other stars and distant galaxies? Clearly we cannot measure these directly. Nevertheless there are many indirect methods of measurement, combined with basic high-school mathematics, which can allow one to get quite convincing and accurate results without the need for advanced technology (for instance, even the ancient Greeks could compute the distances from the earth to the sun and moon to moderate accuracy).

These methods rely on climbing a "cosmic distance ladder", using measurements of nearby distances to then deduce estimates on distances slightly further away; we shall discuss several of the rungs in this ladder in this talk.

Ask a question

Professor Tao will be joining the Chair, Professor Pauline Mellon of UCD and President of Irish Mathematical Society, by video link from Los Angeles to record this lecture. If you have a question you'd like to put to Professor Tao during this event, please email it to by 12:00 on Friday, 2 October, along with your name and location. Tune in to the lecture broadcast at 16:00 on Friday, 16 October to see if your question is asked.

Professor Terence Tao

Terence Tao was born in Adelaide, Australia in 1975. He has been a professor of mathematics at UCLA since 1999, having completed his PhD under Elias Stein at Princeton in 1996. Tao's areas of research include harmonic analysis, PDE, combinatorics, and number theory.

He has received a number of awards, including the Bochner Prize in 2002, the Fields Medal in 2006, the MacArthur Fellowship in 2007, the Waterman Award in 2008, the Nemmers Prize in 2010, the Crafoord prize in 2012, andthe Breakthrough Prize in Mathematics in 2015.

Terence Tao also currently holds the James and Carol Collins chair in mathematics at UCLA, and is a Fellow of the Royal Society, the Australian Academy of Sciences (Corresponding Member), the National Academy of Sciences (Foreign member), and the American Academy of Arts and Sciences.

Hamilton Day is kindly supported by Ibec.

If your question is selected by the chair it will be included in the recording. Read our Data Protection Policy and our Eventbrite Transparency Statement . Further details on our data protection policy may be obtained by emailing

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