Ph.D. Defense - Procedure and Advice
Here are some notes for candidates going into a PhD thesis defense. We hope they are useful to you. Please let the Departmental Grad Supervisor know if items should be added for candidates in future defenses.
- If you need a computer and data projector for the defence, please make these arrangements ahead of time yourself. The departmental data projector availability and booking instructions are available on the booking webpage. Room 4351 has a ceiling-mounted projector and 3230 has a large wall-mount LCD panel. You can use those instead but give yourself time to figure out the controls.
- Please arrive at the exam room early to set up your projector, computer or whatever you need comfortably in advance of the start of the exam. The examiners will be arriving and you can meet them informally.
- The exam is "closed". Other faculty are permitted by the rules to attend, but never do. People such as other students may attend only with your permission and that of the Exam Chair. People should ask you in advance.
- The Chair for a PhD exam will be someone remote from the Physics Dept who will basically just run the exam. Past chairs have come from the social sciences, engineering...
- When all the examiners have arrived, the Exam Chair will ask you to leave for a period of time while they review your academic record and get set for the exam. This could easily take 10 minutes or more because the External Examiner will be asked to go over his/her written report. Just let the time pass; it doesn't indicate anything at all.
- The Exam Chair will then ask you to return to the room.
- The Exam Chair will outline the procedure of the exam - basically what follows below.
- You will be asked to present the essence of your thesis to the committee. Your presentation can be up to 20 minutes long. Do not go overtime; being slightly undertime would be just fine. It's difficult to squeeze all the work of a thesis into 20 min or less but keep in mind that the examiners have all read your thesis and have prepared questions for you in advance. They'll be very happy if you only take 15 minutes. My advice is to make the general intro slightly shorter than is needed for a good OCIP talk, then try to cover the highlights of your thesis, and finish with the essential bottom line of what advancement your work has made. When you use figures and tables from the thesis, direct reference to figure number/table number, or page numbers, can be helpful.
- Then there will be two rounds of questions. In Round 1, each examiner in turn will have a few minutes. The External Examiner goes first, and typically the order of the rest is to move from
"distant" to "closer" in terms of field. So the non-physicist on the committee will ask early and
your supervisor will ask last. Potentially the Exam Chair might ask something just out of curiosity. In terms of time, it is variable, but as a ballpark value the External Examiner might have up to 20 minutes, while the other examiners usually are 15 min. They could take less, but occasionally more.
- In Round 2, the same order of questioning is followed, but people can now interject and discuss. Round 2 is usually much shorter than Round 1.
- After both rounds of questions, you may make a closing statement if you desire. This is optional.
- The Exam Chair will ask you to leave the room while the committee decides on the outcome of the exam. Their time to deliberate is highly variable - from a few minutes to a few tens of minutes. Do not sweat it: they might be discussing some obscure technical detail. Their deliberations might have drifted beyond your work to something else.
- After some time you will be invited to return. The Exam Chair will tell you the outcome. It's over!
If all has gone well (and everyone involved does fully expect that) everyone will congratulate you.
- It's usually the case that revisions will be required. Usually each examiner will have either a list for you and/or will return your thesis with changes highlighted. In addition to the detailed material from everyone, the Exam Chair will make up a master list.
Some General Advice
Prepare your presentation well in advance, so that you can get a good night's sleep before the exam.
You should bring your thesis to the exam, and don't hesitate to consult it as needed before answering a
Go ahead and bring a drink and/or snack.
Come prepared to discuss and defend your scientific work. While the examiners can ask whatever they want, the questions almost always arise somewhere out of the thesis work or the motivation for doing it.
Don't rush to answer a question off the top of your head - take your time to compose yourself. Make sure you understand what the question is, and ask for clarification if you don't. Use the board as needed. If you really don't know the answer to a question, just say so.
Take the questions at face value. If they seem elementary, they probably are to you, but maybe not to the examiner. Remember that you know more about the details of what you did than anyone in the room. Sometimes a simple question is a warmup to something else, but take it one question at a time.
The examiners will have already assessed your written work. During the exam they want to hear more about it, clarify some items, and assess your scientific mastery of the project. You are the expert. Go in there and just tell them what you did.