Thursday, 19 May 2022

14 year-olds using matrices

Coming up soon is the Qiskit Global Summer School which is something I'm suggesting some of my students attend.

I was wondering whether at least some of it might be far too elementary for them, as the summer school is open to students aged 14 and over, with a prerequisite of knowledge that attendees know some basic maths including matrices.  One of the co-supervisors I was discussing this with, who is a bit younger than me, commented that he'd never come across a 14 year old who knew about matrices, which reminded me that today's students indeed don't come across them at that age.

I happened to have on my desk a copy of Book 4 volume 2 of the School Mathematics Project textbook that I used at school.  Indeed, it has a stamp in it of my secondary school, and it is presumably a copy I should have, but didn't, give back to them after using.

Here's a picture of the first page, the start of chapter 11 (it being volume 2, after all)

Its opening sentence is "we saw in Book 3 how a matrix could be used to represent a transformation ..." so matrices were obvioulsy introduced no later than book 3, possibly eariler.  Inserted into this book was a folded timetable for my 3rd year (Y9 in current terminology) timetable, so I suppose I used book 4 volume 2 in that year.  Clearly, I was a 14 year old once who knew about matrices.  Being taught them then was so matter of fact that I never thought much about it.  There was a simple enough rule for multiplying them and that was effectively all that one needs to learn about matrices to use them.  Applications, such as using them for geometrical transformations, is another matter, and one can find ever more esoteric and advanced applications, but the basic properties are really rather simple.  Of course, I am the sort of person who ended up doing a PhD in theoretical physics, but the educationalists of the time presumably thought matrices a perfectly wholesome activity for 11/12 year-olds.

Tuesday, 17 May 2022

RIP Ben Mottelson 1926 - 2022

I saw announced on Facebook, via my colleague and friend Adam Maj from Krakow, that Ben Mottelson has died.  It took a couple of days for Wikipedia to catch up, but there I saw a link to a Danish news story seeming to confirm it.

Ben Mottelson was a co-recipient of the 1975 Nobel Prize for his work in nuclear physics, specifically unifying the theories of single particle and collective motion in nuclei, and for showing that nuclei could be deformed in their ground states.  The co-recipients of the prize, Aage Bohr and James Rainwater died in 1986 and 2009 respectively.  Mottelson worked closely with Aage Bohr and though the prize was split equally three ways, the prize was effectively for Rainwater's work and for Bohr and Mottelson's largely joint work.

I don't think I've ever seen Mottelson at a conference or anywhere else, and have little I can add personally as an anecdote.   He is most well-known to me as the author of the two volumes, with Aage Bohr, of the the Nuclear Structure textbook.  This seminal work educated generations of nuclear physicsists.  I'm afraid I haven't studied the book as much as either I should have or would have liked to, and only eventually acquired my own copy rather recently, but here I am having (or pretending to for the camera) a read of it

Friday, 13 May 2022

The Liverpool Synchrocyclotron

There's in intersting article in Physics World this month about the Liverpool Synchrocyclotron.  For a period in the 1950s it was in the first tier of leading particle accelerators for nuclear and particle physics.  It innovated in the extraction of the beam from the cyclotron into a beam line to be directed at a target.  This is now a commonplace setup, but beforehand targets and detectors all had to be inserted inside the synchrotrons themselves.

The picture below, included in the Physics World article courtesy of The Victoria Gallery & Museum, University of Liverpool, shows the huge magnet being delivered to the site in 1951.  If it wasn't for the truck delivering an enormous magnet, I might have guessed the picture was much older.

Thursday, 12 May 2022

New paper up on quantum computing

A new paper from my PhD student Isaac, me, and the other co-supervisor appeared (or "dropped" as the young people say) on the arXiv this morning.  It's somewhat broad title "Quantum Computing for Nuclear Structure and Nuclear Data" is to some extent due to the fact that the paper is a conference proceeding associated with a poster presentation of the same name, presented at a very general quantum technologies conference (SPIE Quantum Technologies 2022).

The content is a bit more specific, and deals with a couple of examples of applying the variational quantum eigensolver algorithm to nuclear Hamiltonians.  Both the examples we look at have been explored on quantum computer already, but we show the results of using a different, more compact, mapping from the Hamiltonian to the qubit representation, and a method for finding excited states with a variational methtod (by minimizing the variance of the Hamiltonian with respect to the parameters in the trial wave function).  The paper is not a full description of everything Isaac has done or is working on, but the kind of work-in-progress conference paper you might expect to be associated with a poster presentation.  It's nice to have our name out there as a group working on quantum computing algorithms in nuclear physics.  Will be interesting to see what response it gets.

Here's a picture showing the energy as a function of two variational parameters in the wave function ansatz we used for one of the problems we were looking at (the deuteron ground state):

Tuesday, 10 May 2022

Flamin' Groovies

Hot on the heels of my visit to London to see the Divine Comedy, I went to another gig on Saturday.  This time it was at the 100 Club on Oxford St, to see the Flamin' Groovies.  I took my Dad, as a birthday present for him.  I had looked through the listings for bands I thought he might want to see.  I had heard of The Flamin' Groovies, but didn't really know them, and my Dad had not heard of them, but they've been around since the late 60's, and the idea of going to the 100 Club, where my Dad used to go around half a century ago to listen to jazz, decided us in favour of this being the birthday present.  My Dad and I have a combined age of 122, but it certianly wasn't the kind of gig where either of us felt particularly old or out of place.  At one point, though, the lead singer did say he needed to pause and catch his breath, and that he was 74 ("youngster" my 75yo Dad muttered).  Despite their age, the band rocked pretty hard!

Friday, 6 May 2022

Departmental Colloquium Series: Michelle Collins

I've just got back from Michelle Collins' excellent talk as the first speaker in a new colloquium series being organised in the Department of Physics by Payel Das and Jack Henderson.  These are supposed to be accessible research talks given to a whole-department audience as a way of bringing us together after the lockdown period, and as a way for us to better know what we each get up to research-wise.  Who knows, maybe it will start some new collaboraitons?  Michelle talked about dwarf galaxies as a way to understand the dark matter structure of the universe.  There were lots of pretty pictures taken with telescopes, though I think it did need guidance from the expert eye to understand the significance of blurry patches of the starfields which to me were just ... blurry patches.

Here's the view from where I sat.  I went fairly far back because I was going to sit and do some emails.   The talk, though, was too interesting, and I left the emails until after both the talk, and writing this blogpost about it!

Thursday, 5 May 2022

The Divine Comedy

Yesterday was a busy day with meetings: meeting personal tutees, then a session of the department Equality Diversity and Inclusion committee.  Straight from that into my weekly research group catch-up meeting, then straight to a parent information briefing from the University nursery where my son goes, then a call with the research student office to help fill in some paperwork for a new PhD student, then a final year project student meeting in my office followed by an online chat with a placement student of ours who is working at JLab in the US.  As soon as that was over, a whole-research-group strategy meeting.  It was definitely a case of eating lunch al desko.

So, it was a nice end of the day to take a train up to London to see the band The Divide Comedy at the London Palladium.  I'm not sure if I've ever been there before.  It's a bit of a bigger venue than for most bands I tend to see, but a friend had a spare ticket and I like the band so I went along, and very enjoyable it was.  I don't consider myself a super-fan, but I first heard them around the time they started ~30 years ago, when my then-girlfriend bought a single of theirs which I most remember because it had a cover version of The Throwing Muses' Hate My Way on one side.  This somewhat obscure cover of a somewhat obscure song from a limited edition picture disc EP is certainly not something they played in their kind of greatest hits show last night, but I looked up the song online, and here it is.  A picture from last night's show is at the top