Wednesday, March 14, 2012

The accelerating universe by Nobel Laureate Brian Schmidt

Greetings from the Australian National University in Canberra, where Professor Ian Young Vice-Chancellor is introducing Nobel Laurette Professor Brian SchmidtProfessor Brian Schmidt, winner of the 2011 Nobel Prize in Physics will speak on "The accelerating universe". Professor Schmidt started with a tour of the universe, as measured by the speed of light: the sun is 5 light seconds in diameter and 8 light minutes from the earth. He went on to explain different models of the universe as an introduction to his work on measuring the rate of change in size of the universe. He used Type 1A Supernovas as benchmarks to measure the rate of change and concluded the universe is expanding at an accelerating rate published as "Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant".

Professor Schmidt explained that apart from more powerful telescopes, it was high performance computers which allowed for observations. He also mentioned the role of competition, with two groups of astronomers. One team concluded the universe was slowing down, as expected and then changed their minds, causing the two teams to rush to publication.

Professor Schmidt's presentation was interrupted by a problem with the presentation from his laptop. This was a useful reminder that technology being used in education needs to be reliable. In this case the computer built into the lecture theater could be used as a backup and continue the presentation.

In answer to a question Professor Schmidt said he is now working on "SkyMapper", a relatively small 1.35 metre telescope, but with very fast image processing, recording 100 Megabytes of data per second. This can then be used to detect rapid changes in the sky.

In answer to another question Professor Schmidt speculated the Large Hadron Collider may discover dark matter.

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