Wednesday, 24 October 2012

Lunchtime recitals & Evening talk

I've only been working here for a mere 12 years, and during all that time, I had never been to one of the weekly lunchtime recitals put on by the music department.  I managed to remedy that today by making the two minute walk from my office to the performing arts studio and listening to final year students perform.  It was heavily flute-themed, beginning with a piece by Carl Reinecke, accompanied by piano, another accompanied piece by Ian Clarke, dating from 2007 (and rather good, I thought), then a Rachmaninoff piano piece, which started off quietly and ended with a loud crashing tempestuous finale, and then back to a calmer flute solo piece by Telemann.

It is easy to forget that there still survives an aspect of University life which is about very highly-educated people sharing a communal experience of being amongst other very highly-educated people and engaging with each other.  So often it feels like I am here to do a job, to make bosses happy, to satisfy various metrics, but every now and then a glimpse of some crazy idealistic view of the academy peeks through.

So, more fool me for waiting so long before attending... and really, there is so much else going on that one can attend, but I rarely do so.  I even organise one series of events here, albeit under the cover of the Institute of Physics.  In fact, tonight we kick off this (academic) year's programme of evening public lectures on physics (and related topics), with Jon Butterworth of UCL (and Horizon and the Guardian, etc.) talking about a euphemistic "discovery" at the LHC earlier this year.  If you are a reader of this blog (if there are any) and you are in Guildford, feel free to come along this evening.  It should be a great talk, and I'm really looking forward to it.

Monday, 22 October 2012

Flora and Wagner

This morning, when driving my daughter Flora to school, I felt in a kind mood, and offered that we could stop listening to radio 4 (which she professes to hate, but still asks things about what they say) and suggested radio 2.  She gladly said yes, hoping for music, and indeed we were treated to The Fog on the Tyne (Lindisfarne version, thankfully - though she didn't say anything about the "we can have a wee-wee" line).  After a while she got tired of Chris Evans talking, and asked what was on radio 6 and radio 5, and I tried to explain (and that we couldn't listen to radio 6 or 5 in the car).  I then mentioned radio 3 and that it played classical music, and asked if she wanted to listen.  She said yes. 

It is now her favourite radio station.  When we turned it over, the music playing was Huldigungsmarsch by Richard Wagner.  She was absolutely delighted (having spend the journey thus far complaining about the traffic and how boring the journey was and how long it would take).  "Daddy!  It's like a carousel!  It's like a carousel, isn't it Daddy?" she said,  and we spent the rest of the journey listening to Radio 3.  Every time I turned it down to hear what she was asking, she forgot her question and just told me to turn it back up.  Hopefully this is going to make car journeys more enjoyable for all of us!

Edit: Here's Lindisfarne's Fog on the Tyne:

and here's Wagner's Huldigungsmarsch:

Tuesday, 16 October 2012

How many naturally-occurring elements are there?

The editor of Nature Chemistry, @stuartcantrill and I follow each other on Twitter.  If memory serves, that followed from a quick exchange about the correct value of the number of naturally-occuring isotopes between us.  The subject has come up again, with Stuart (correctly) correcting the value given in a blog post he tweeted about.

The question is not at all easy to answer.  It depends what you mean by naturally-occurring.  I think the common meaning is "can be dug up from the ground but didn't come from man-made sources such as weapons fallout."  So, how many is that?  Well, definitely any element with a stable isotope can be included there.  How many elements have stable - i.e. non-radioactive - isotopes?  If you look at a table of isotopes, such as this one you can look for the squares shaded in black, which is the usual notation for a stable isotope.  That gives us everything from Hydrogen (element 1) up to Bismuth (element 83) with gaps for Technitium (element 43) and Promethium (element 61).  The complicated thing is that really, everything heavier than around Nickel or Iron (around element 26) is know to be theoretically unstable, and in fact the decay of the only "stable" Bismuth isotope has been observed.

Still, it turns out that all the isotopes listed as "stable" in the chart can be dug out of the ground, and trace amounts of Technetium and Promethium are found in nature, because Uranium can be dug out of the ground, and though all isotopes of it are radioactive, they sometimes decay by spontaneously fissioning into lighter isotopes, which include Technetium and Promethium.

It is for similar reasons that some other radioactive-only isotopes can be found on the Earth, and this includes isotopes of all the elements heavier than Bismuth but lighter than Uranium (things like Polonium and Radon).  It seems that a bit of Neptunium and Plutonium (elements 93 and 94) can be found in Uranium ores, too.  According to this page found by Stuart, the number may be even higher, though I'd like to see the references to the papers where the things heavier than Plutonium were observed in non-man-made matter.

In some ways, though, the question is a bit academic.  If we extend our remit to the stars, where all elements heavier than lithium are made, then surely even heavier elements than those that can be dug out of the ground are found - at least fleetingly during novae and supernovae.  Stars are part of nature, after all.  What is clear is that we know that at least 118 elements exist in isotopes for long enough to say that they exist.  We also know, or suspect, that there will be an upper limit to this number, but exactly where that is, we're still trying to work out.

Friday, 12 October 2012

Sea U, Jimmy.

Every quarter, I get sent a copy of Nuclear Connect, a kind of trade journal for the nuclear industry.  There was one particular news story that interested me that I thought I'd pass on.  It concerns a recent announcement at an American Chemical Society, reported by them in a news story here.

The short story is that there is supposed to be at least 4 billion tons of uranium dissolved in seawater.  That's a staggering amount, but of course there is a lot of seawater out there, and even a low concentration of uranium could still amount to an overall huge weight.  Wikipedia seems to think there is about 109 billion tons of water on the Earth.

Apparently a technique, developed in Japan, has cut the cost of extracting uranium from the sea to around $300 per pound of uranium.  That would be at the natural isotopic abundance, presumably, so would need to be enriched for fuel. But still, to know that there is a huge reserve of uranium that can be extracted is useful.  It can always form a backup in case we don't come up with something better.

Tuesday, 9 October 2012

Sex, drugs and nuclear physics

Thanks to @scamperscamper and @thisiswilton for sharing the following on Facebook.  Nuclear Physics is getting some of the glamorous status that it clearly deserves at long last.