Thesis Defence Slides: What to Cut From 200 Pages

A defence is not a summary of your thesis. It is an argument for one claim, presented to people who will push on the weakest part of it. That single difference decides what to cut: your chapters are how the document is organised, not how the argument runs, and a talk that walks through them in order spends its best minutes on the parts nobody disputes.

The shape that works

Fifteen to twenty-five slides for a twenty-minute slot, then a backup section that does not count:

• The claim, on slide two. One sentence, and everything after it is support. If the committee cannot repeat your claim afterwards, nothing else in the deck mattered.
• Why it was open. What the field had, and precisely what it did not. This is where the literature goes, in three slides, not fifteen.
• What you did. Enough method to make the evidence readable, no more. Detail belongs in backup.
• The evidence, weighted by contention. The result you expect to be challenged gets three slides. The one nobody doubts gets a line.
• Limits, stated by you. Naming your own weakness turns an attack into a conversation. Leaving it out invites the question anyway, with worse framing.
• What follows. Short. This is where a committee decides whether you understand your own contribution.

Backup slides are the actual defence

Everyone in the room knows which questions are coming: the ablation you did not run, the baseline you did not compare to, the derivation you compressed, the one adjacent paper somebody always raises. Build a slide for each and put them after your closing frame. Being able to say "yes, slide 31" and jump to a figure is the single most convincing thing that can happen in a defence, and it costs an afternoon.

In Beamer, keep them out of the numbering so the talk still reads as twenty slides:

\appendix
\begin{frame}[noframenumbering]{Backup: ablation without the pretraining step}
  ...
\end{frame}

Pulling the deck out of the thesis

The mechanical part, lifting figures and results out of a 200-page document, is worth handing off. The judgment part is not, and these prompts are written to keep that line:

Templates and the document itself

There are defence decks in the presentation templates, and if you are still writing the thesis rather than defending it, the university thesis templates cover the layouts departments expect. For the deck itself, the preamble that removes the Beamer tells applies here too: a defence deck does not need a navigation bar either.