On the presentation of results during the viva exam

Question

In a few weeks time I will be having my viva exam and I was wondering of a few things regarding the presentation in which I will be presenting four algorithms from four of my published papers.

Since my advisor recommended that the presentation be less than 25 slides due to the viva time limit and given that each of the papers that is included in it is around 10-15 pages long I was wondering of how synoptic each of my algorithm presentations must be in order to meet the slide-number requirement.

I have already prepared the slides but I feel that the algorithm presentations are too brief to be very useful for presenting them. Since I haven't done such presentation for a long time I was wondering if you have any advise or tips regarding brief viva presentations.

Answer 1

I recommend you urgently go back to your advisor to clarify both the audience and the time line of your viva. 45 min for a viva sounds way too short and this makes me wonder if there is a second component to the viva.
You should also find someone who recently graduated from your institution and ask them about their viva experience, as details can be very institution specific and generic advice from the internet might not help.

Having said this, in a viva in the UK, the examiners will have read your thesis beforehand, so they will know what you are talking about and you should pitch your talk accordingly. Typically what examiners are interested in is a) what exactly your contributions to the presented results were (ideally this would be clear from the thesis, but it can be surprisingly difficult to discern, especially as yours sounds like a "stapler thesis" consisting on published papers) and b) what you consider your greatest achievement of your thesis, i.e. how did your thesis contribute to progress in the field. That was the very first question I got in my own viva in physics, and as far as I can tell it's an absolute standard question for PhD exams, STEM or not.
So it's important not to get bogged down in the details (e.g. rather than explaining how your algorithm works, focus on what makes it special), but focus on the big picture. The examiners will typically bring notes and ask questions about issues they didn't understand in your thesis and also often about ones they did, just to ensure that you actually understand what you are talking about - it is an exam after all.
Good luck!

Answer 2

Assuming that the "judges" will have an opportunity to question you after the presentation, your "detail" can be much reduced.

Prioritize your presentation and the number of slides devoted to each point by the overall "importance" of a concept/algorithm is to your overall work. Each big idea should have at least two slides: background/concept and results. The more important ones, or the ones that give the most insight deserve more detail. But don't try to replicate the papers in the presentation, trying to answer all objections/questions.

In the slides you can point to important details in the papers by page and line number rather than presenting all the details.

Don't interpret this as a suggestion to leave out all details. But focus time and space on the most important things and expect that questioners will fill in what they don't find clear. I suggest you have additional slides ready that you don't present initially but that you can bring up when/if questions arise.

I suggest that you run your presentation by your advisor prior to the actual viva if possible and permitted.