Tuesday, 29 November 2011

Science makes us feel stupid

I recently visited a good friend who has always had an awesome attitude to his science. In order to not reveal their name, I will call them Bob.

All through Bob's PhD he always seemed really motivated even when metaphorically beating his head against the wall trying to get some obscure results. But what's important to me as a scientist is that Bob always asked the BEST questions - the ones I really hadn't thought about before but make me think in a new way about my research. I think this quality of Bob's could make him a truly great scientist - I have always really enjoyed having science discussions with him.

I was a bit shocked then, when I caught up with him recently, to find him using words which I keep hearing more and more now that my 'cohort' are finishing PhDs and moving on. For those that choose to continue in research I hear words like "feeling isolated", having a lot of "self-doubt", wondering if science is "for me". I hear people saying this not just occasionally, but when it comes down to it, all the time!

Perhaps I'm only noticing it because I've been doing postdoctoral research for just over a year myself and I have at times (OK, quite often) wondered the same thing?

To top it off I keep discovering awesome scientists leaving science to go and do other things not because there aren't any jobs*, but because they don't enjoy it any more or because they don't feel they are good enough. I've heard this from both men and women, although the women seem to be more open about their feelings and reasons for leaving.

To be fair, a lot of people I know in this position are talented science communicators so will still be using science, just not in a research career. But... surely there is a failing of the "system" somewhere here where our bright, talented, promising PhD graduates suddenly feel like they just aren't up to the task of actually doing science?

It would be easy to blame it on training, on supervisor support, on any number of things. But perhaps it's just that today, more than ever, we strive to have jobs that we enjoy, that mean something to us and that are satisfying. Science is (often) not a satifying job on a day to day basis. You can spend weeks working on a single problem feeling like you're bashing your head against the wall and then discover it was all for nothing.

One of the things I've come to realise is that just loving science isn't quite enough. You have to be prepared to feel stupid on a day-to-day basis. Because sometimes, that's just science. Thanks to a great discussion I had recently with a guy who introduced himself as Bill**  I have come to recognise that it's not just me who feels stupid in science - in fact there are many arguments to be made that if you've stopped feeling stupid then you've stopped really doing science.

This is a career in which we uncover the unknown, and it's not easy. But at the same time, recognising that everyone else feels the same way is worth a lot to me. So for now, at least, I'm sticking with it. I just hope I can convince my friends to do the same...

*As a side note there are obviously many other reasons why people leave science, but this is just one that I've been coming up against a lot recently. The "bright, talented, promising" people that do PhDs often quite rightly feel they would get more satisfaction elsewhere. Somewhere with scientific challenges, but a career that has good rewards for hard work, where their efforts are appreciated (and not quashed by ambitious senior postdocs scrabbling to get recognition to get the next job), and where they feel some level of job security. Because, let's face it, who wants to pay rent and move around the world every 2-3 years? Very few relationships can stand that and anyone wanting to 'settle down' and have kids or buy a house has an almost impossible task if they are in the academic science post-doc circuit unless they are very very lucky.

**turned out he was Bill Phillips, 1997 Nobel Prize in Physics

Tuesday, 22 November 2011

What happens if you put your head in the LHC beam?

I'd like to show you my FameLab SE Final talk, and then further down in this post I'll discuss in more detail what happens when you stick your head in the beam of a particle accelerator. Without further ado, here is the video:

I was a bit nervous being first up on the night, which clearly made me talk really fast. I was wondering how I'd chopped a good 10-15 seconds out of my talk! Well, now I know.

I was inspired to talk about this topic for two reasons: firstly, my PhD was in designing particle accelerators for particle therapy (including proton therapy) which directly uses the beam from an accelerator to treat certain types of cancer. The second reason was that I thought the results which come up when you Google this weren't very satisfactory... Although there is one quite interesting video getting scientists to give their initial thoughts on the effects of putting your hand in the LHC beam

Now down to some science - where did the crazy numbers I gave in my talk come from?

Let's start with how much energy is dumped in your head when the LHC proton beam goes through it. Usually, I would get this data from NIST, but if you visit their website, you'll notice that the data for protons only goes up to about 10 GeV in energy (that is 700 times lower in energy than the nominal LHC proton beam energy). So what do we do?

Let's pretend your head is made of muscle, if you have a look at the graph below of proton energy loss (stopping power) in muscle that I got from the NIST website, you can see that it kind of levels-off at high energies. I took the value of energy loss to be 2.5 MeV/cm (this assumes the density of the head is something like 1.0 g/cm^3, which is the same as water, so pretty reasonable). 

This is the big 'assumption' I had to make as the data simply isn't available for higher energies!

If the head is about 20cm thick (another assumption), each proton loses 50 MeV of energy each time it passes through the head. In joules, this turns out to be 8.011E-12 J, so not much, really!

Now, in the LHC beam there are 1.15E+11 protons per bunch, and 2808 bunches per beam. So this means that the total energy loss per bunch is 0.9213 J and therefore per beam is 2586.88 J - this is a lot! 

The LHC beam is travelling so fast that in one second it can go around the 27km ring about 11,000 times. So if you put your head in the beam for one second, the total energy absorbed by your head would be: 2586.88 x 11,000 = 28,455,659 J. (Here I have assumed that you only get in the way of one (not both) beams, and that the change in position of the beam losing 10% of it's energy would not lose the whole beam in the machine, which might be unrealistic, but not as unrealistic as the idea of putting your head in the beam anyway...)

But Joules don't mean much to anyone, so lets calculate the absorbed radiation dose in Gray (Gy). We know that a dose of 5 Gy will lead to death within 14 days, and this is equivalent to receiving 375 J for a 75kg adult.

So if we divide our energy absorbed (28,455,659 J) by 375 J, we find out that: 

Putting your head in the LHC beam for one second would kill you not just once, but 75,882 times.

If there's one thing I can leave you with, though, it's that proton therapy using smaller accelerators providing much lower doses can (and does!) treat certain types of cancer much more effectively than X-ray radiotherapy. I encourage you to look it up - although for the sake of keeping this post from being thesis-length, I won't describe it here now. Maybe that will have to wait for a future post...

Friday, 18 November 2011

FameLab - SE Regional Final

Just a quick update to say a big congratulations to Andrew Steele who managed to win the SE Final of FameLab at Science Oxford last night with a very impressive talk about climate change, clouds getting whiter, and why perhaps we should be wary of geo-engineering. 

The competition was TOUGH - I have to say I was blown away by the impressive quality of presentations. Lots of people I'd definitely want to work with on sci comm projects in the future.

I was first up - never a good thing for nerves - but I was much happier this time around with how my talk went. I talked about what would happen if you put your head in the beam of a particle accelerator. I won't give away all my tricks quite yet though, I'll wait until the video is up and then write another post around that, including a few calculations I had to do along the way.

A nice surprise was that a guy called Niraj Lal was also competing - he was actually picked as one of the wildcards to possibly go through to the National final. It turns out we know each other from studying Physics at Melbourne Uni. We even spent 2 weeks in the same car on a geeky roadtrip to the middle of the desert in Australia in 2003 to see the total solar eclipse near Ceduna. Amazing to have such a blast from the past - it (and his presentation, which you just have to see to believe) - totally made my night.

Congratulations as well to Ceri Brenner - fellow LMH-alumni and also fellow Rutherford Lab person who was picked as the second wildcard with her talk about laser plasma accelerators. If nothing else, having Andrew (who works with accelerators) and Ceri (who wants to shrink the size of them down) in the National Final will mean lots of accelerator science getting out there, which is a good thing!