# Collabor8 – A New Type of Conference

Next month, I’m running a day-long conference here at QMUL. The meeting is intended to give early career researchers the chance to seek possible collaborations. Despite living in this globalised age, all too often PhD students and postdocs are restricted to working with faculty members in their current institution. This is no surprise – at the conferences and meetings where networking opportunities arise, we’re usually talking about completed work, rather than discussing new problems.

We’re shaking up the status quo by asking our participants to speak about ongoing research, and in particular to outline roadblocks where they need input from theorists with different expertise. What’s more, we’re throwing together random teams for speed collaboration sessions on the issues presented, getting the ball rolling for possible acknowledgements and group projects. We’re extremely fortunate to have the inspirational Fernando Alday as our guest speaker, a serial collaborator himself.

The final novelty of this conference comes in digital form. The conference website doubles as a social network, making it easy to keep track of your connections and maintain interactions after the meeting. We hope to generate good content on the site during the day, where some participants will be invited to act as scribes and note down any interesting ideas that arise. This way, there’ll be a valuable and evolving database of ideas ready for future collaborations to draw on.

Over to you! If you’re doing a PhD or a postdoc in the UK, or you know someone who is, send them a link to the website

http://www.collabor8research.org

If you’re further afield, feel free to follow developments from afar. In the long term we’re hoping to roll out the social network to other conferences and institutions – watch this space!

# Using Thunderbird Client with Office 365

I’ve just wasted a good half hour trying to migrate my email to an Office365 SMTP server. It seems that QMUL have decided to discontinue their in-house email server, but have not provided sufficient details about the new settings needed for email clients.

So here they are, in case anyone else runs into difficulties.

SMTP server : smtp.office365.com
Port : 587 (not the default)
Encryption : STARTTLS (not SSL/TLS)

I imagine that similar settings should work for other institutions which have moved to an Office365 system.

# Counting Microstates with Lateral Thinking

I’ve spent some time this morning stuck on the following undergraduate problem

Consider a quantum system with $N$ distinguishable particles, each of which can have energy $E=n\epsilon$. Show that the number of microstates consistent with a macrostate of energy $E$ is given by the binomial coefficient

$\displaystyle \left(\frac{E/\epsilon + N - 1}{N - 1}\right)$

This is a classic example of a problem which needs some lateral thinking! It’s pretty trivial when you get the right idea, but I think it’s not entirely obvious at first. I’ll share with you my (embarrassingly slow) reasoning – let me know whether you agree with my philosophy in the comments.

To start with, I tried some examples – attempting to arrange $3$ particles in $5$ energy levels for instance. My approach was to work out how I could partition $5$ as a sum of smaller numbers, then evaluate the number of possible configurations consistent with this.

More concretely, I had a configuration where the particles had energies $\{0,1,4\}$. There are $3 \times 2=6$ such arrangements, because the particles can be distinguished (think of them as different coloured balls, if you like).

That’s all very well, but generalizing this idea is tricky. The problem is that the total energy constraint $\sum E_i = E$ makes it hard to enumerate all possible configurations. So I sat, stumped, for a good few minutes.

But thankfully, my failure contained a vital clue. My difficulties lay with that irritating total energy constraint. What if I could remove it from the problem altogether?

To do this requires a bit of lateral thinking. We’ve been trying to fit particles into energy levels. But you can turn the problem around. Equivalently we can try to distribute the $E/\epsilon$ units of energy among the particles. This effectively trivializes the troublesome constraint.

We’re not quite out of the woods yet. We need to work out how to distribute the energy blocks into the particle buckets. Here a second piece of lateral thinking helps us out. Rather than throwing the energy into buckets, we can think of partitioning it into sections. It’s just like being at the supermarket till – different customers (particles) separate their shopping (energy) with plastic dividers.

So how many ways can we divvy up the shopping on the conveyor belt? Well, there are $N$ customers so we’ll need $N-1$ dividers. We’ve also got $E/\epsilon$ items ready to be bought. This means that you have

$\displaystyle (E/\epsilon + N - 1)!$

possible arrangements of the items and dividers. But hang on, every unit of energy looks exactly the same. It’s as if every customer has bought exactly the same product! And clearly it doesn’t matter if you exchange the dividers – the overall partition is unchanged. Taking this into account, the correct number of microstates is

$\displaystyle \frac{(E/\epsilon + N - 1)!}{(E/\epsilon)!(N - 1)!}$

This is exactly the binomial coefficient in the question above!

Although this problem was pretty simple, there are two important morals. First, always examine a problem from every angle. Second, never completely discard your failed attempts. Chances are they hold vital clues which will point you in the right direction!

# Elsevier Journals – The QMUL Figure

A few weeks ago I reblogged Tim Gowers’ post about the cost of Elsevier journals. I noticed that my own institution (QMUL) had deflected his Freedom of Information request. Curious to learn more, I did some digging.

It turns out that QMUL paid a total of £454,422.44 to Elsevier for the academic year 2013/14. Interestingly this is more than Exeter and York, who also joined the Russell Group recently. However it’s still much cheaper than the bill Cambridge, UCL, Imperial or Edinburgh face.

Unfortunately QMUL weren’t able to provide any further breakdown of the figures. Apparently this information isn’t available to the university, which seems like a very odd way of doing business. I think it likely that the vast majority of the cost is the subscription fee.

I should point out that QMUL and Cambridge certainly have differentiated access to Elsevier journals. For example QMUL Library does not have access to Science Direct papers before the early 1990s. Cambridge University Library has universal access to this material.

However with all the smoke and mirrors in this story, it’s impossible to turn this anecdotal evidence into an accurate account of Elsevier’s charging policy. There’s clearly a need for much greater transparency.

Below is a transcript of the email I received from the QMUL FOI Department. I owe a debt of gratitude for their help.

Dear Edward Hughes

Thank you for your email of 25th April requesting information about spend on Elsevier journals at Queen Mary University of London.

The total amount paid to Elsevier for 2013/14 was £545,306.93 (inclusive of £90,884.49 VAT). We do not hold any further break down.

If you are dissatisfied with this response, you may ask QMUL to conduct a review of this decision.  To do this, please contact the College in writing (including by fax, letter or email), describe the original request, explain your grounds for dissatisfaction, and include an address for correspondence.  You have 40 working days from receipt of this communication to submit a review request.  When the review process has been completed, if you are still dissatisfied, you may ask the Information Commissioner to intervene. Please see www.ico.org.uk for details.

Yours sincerely

Paul Smallcombe

Records & Information Compliance Manager