Archive for May 18, 2017

Gravity in the Quantum Vacuum

Posted in The Universe and Stuff with tags , , , , , on May 18, 2017 by telescoper

Yeterday I noticed an interesting paper which has been on the arXiv for a few months but which has just been published in Physical Review D and has been highlighted by the Editors of that esteemed journal. The authors are Qingdi Wang, Zhen Zhu and Bill Unruh – all of them from the University of British Columbia in Vancouver.

Here is the abstract:

You can click on the image if it is too small to read. As you will see it suggests that we may have been thinking about the effect of vacuum energy in completely the wrong way in the context of Dark Energy.

It’s a long paper (35 pages) which I haven’t had time to work through completely yet, and I don’t know whether it will stand up. I have to say, though, that I’ve long left that the problem of dark energy will only be solved by a fundamental reappraisal of the underlying physics, rather than adding new fields or other such contrivances.

I’d be interested in comments from people who have read the paper thoroughly. I’m flying back to Blighty this evening so I hope I can study the article more thoroughly on the plane.

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R.I.P. Rhodri Morgan (1939-2017)

Posted in Politics with tags , , on May 18, 2017 by telescoper

I was very sad this morning to find the news that Rhodri Morgan passed away yesterday at the age of 77. Rhodri Morgan was the first First Minister of Wales (a post he held from 2000 to 2009) and was also Assembly Member for my constituency until 2011. Rhodri Morgan was a hugely important figure in Welsh Labour Party. As  a charismatic leader and capable administrator,  he was extremely  influential  in the campaign for Welsh devolution and  was held in very high regard across the political spectrum.

I was reminded of Rhodri Morgan earlier this week as I realised that  14th May 2009 (i.e. eight years ago on Sunday) the date on which the Planck and Herschel spacecraft were launched. Was that really so long ago?

Rhodri Morgan was still First Minister when he visited the School of Physics & Astronomy at Cardiff University on the day of the launch. He came across as very likeable, down-to-earth and funny. He’ll be missed by a great many people, but most of all by his wife Julie to whom I express my sincere condolences.

Rest in peace, Rhodri Morgan (1939-2017).