Thursday was probably the most exciting day of my week, because I handed in my thesis! All 131 pages, lovingly printed and bound and signed. It felt like something of an anticlimax actually, since I just handed in the document and that was it. No ceremony, no party, nobody bowing in deepest admiration. No ritual to welcome me to the club of people who have overcome their struggles and finally submitted.
My supervisor Andrew Ranicki was kind enough to walk over to the building with me and see the happy moment. I suspect that he was even more happy about it than I was, and didn’t want to risk anything going wrong in between the printing and submitting. He had a double whammy that week actually, since my mathematical brother Mark submitted his thesis on Wednesday. (Which was REALLY sneaky: I knew he had originally planned to hand in on Friday, but after learning that I would hand in on Thursday he decided to beat me to it. Grr.)
Now what? That’s it, right? All written up and handed in. Time to party until graduation, no? This is at least what many people seem to think, so let me me explain the PhD process for anybody who doesn’t know it.
After submission, the university sends your thesis off to two people who have been chosen to examine you. The first person is a leading expert in your field and generally comes from another UK university. In my case it is Brendan Owens from the University of Glasgow, and he is called the external examiner. I’m really chuffed to have Brendan as my examiner because he’s a lovely bloke as well as being a top-class researcher in knot concordance. In fact, he’s already emailed to point out one small oversight in my thesis, so I know he’ll do a thorough job! The second examiner, called the internal examiner, is chosen from within your own department and should be as close to your field of study as possible. In this role I have Mark Grant, who is a young topologist doing work on motion planning in robotics. He’s not an expert in knot theory but should be able to offer valuable suggestions on the work in the thesis.
And because Mark is young enough not to have ever examined a thesis before, there will be someone at the exam to keep an eye on him! I don’t know what the official name for such a person is, but I’ll have José Miguel Figueroa-O’Farrill doing that job. He isn’t allowed to ask me any questions himself, but is just there to keep an eye on Mark and make sure he’s asking appropriate things. I don’t think he even has to read the thesis if he doesn’t want to.
A PhD examination is called a defence or viva (short for viva voce, which means “live voice” in Latin) and will probably last between 1.5 and 4 hours. (I do know people in other subjects who’ve had 6-hour defences though!) The examiners go through the thesis, asking questions about parts they didn’t understand and making sure that the candidate knows their stuff. They need to be satisfied that the student really did all the work themselves, that they understand all the ideas behind the research and have made a genuine contribution to human knowledge.
My defence is going to be on the afternoon of 11th May, which really doesn’t seem long away given all the stuff I need to learn by then! You’re probably thinking “You wrote it, you surely understand it!”, which is a good point, except that I wrote a lot of those ideas down more than a year ago. And I currently feel less than confident about a lot of the background material to the thesis. There are some very difficult ideas behind slice knots which I regret not having spent more time learning back in the first couple of years of my PhD. I will do my best to revise before the big day, but I am absolutely not taking the defence for granted. Many people tell me it’s just a formality, and my supervisor wouldn’t have let me submit if it wasn’t good enough, but I disagree and think it’s all still to play for.
Having said that, I am also looking forward to the defence. In one sense it’s going to be the most difficult and intense exam ever, but in another sense it’s an opportunity to discuss my work in depth with experts in my field. This is an opportunity I’ll maybe never have again. Nobody is ever going to be forced to read my research after this! I’ve not had to explain my research to anybody for a really long time – not since last summer when I visited Chuck Livingston (my unofficial supervisor over in Indiana), so I’m both looking forward to seeing what people think of it and scared of the criticism it’ll come in for!
So, many thanks to all the people who congratulated me on handing in, but I will be saving all the celebrations for the moment when Brendan and Mark tell me that my thesis is good enough to earn me the title of Doctor!
Addendum: A thesis defence in the UK is not nearly so intimidating as one in the Netherlands, where it is a public event with black-tie dress and about 7 examiners. But some students take advantage of the occasion to do something a little out of the ordinary, such as dancing their PhDs! Take a look at this wonderful video of a knot theory student putting their PhD to music (from about the 1 minute mark). Amusingly, the two helpers at the ceremony are called paranimfs.