Content generated by an LLM with human direction.

Philosophy: show and tell

Eigendeck exists to build interactive show-and-tell sessions — talks where you don't just describe an idea, you demonstrate it live, in front of the audience, and can poke at it as questions come up.

Show, don't (only) tell

Film has a rule: show, don't tell. It doesn't quite work for scientific talks — we genuinely need to tell: define the notation, state the theorem, walk the argument. So the goal isn't to replace telling. It's to show as well.

A traditional slide deck inherits its shape from the 1960s slide projector: a fixed sequence of static images. That was the only option when the "computer" was a carousel of photographic slides. But the machine in front of you can run a simulation, lay out a graph, evaluate a model, and respond to a slider — during the talk. Eigendeck is built around that: a slide can hold a live, interactive demo right next to the math that explains it.

The result is a talk where you can say "and if we increase the field strength…" and then actually drag the slider and let the audience watch what happens.

What this means in practice

A few beliefs shape how the tool works:

• A slide is a stage, not a snapshot. Slides hold live elements — demos, notebooks, videos — alongside text and math, not just pictures of them.
• The technical content is first-class. Real LaTeX via MathJax, a curated set of fonts each paired with a matching math font, so an equation on a Shantell slide looks like it belongs there.
• Authoring should be direct. WYSIWYG on a canvas: drag things where you want them, type math inline, drop in an image or a Jupyter notebook.
• The demos come from anywhere — including LLMs. Many of the interactive pieces in a modern talk are quick one-off visualizations. Building those by hand is slow; building them with an LLM is fast. Eigendeck embeds plain HTML demos, so an LLM session is a perfectly good way to produce one. See Building demos with LLMs.
• Your deck stays yours. Decks are self-contained files; assets you add are embedded and live-watched on disk, so you can keep editing the source.

Where to go next

• Building a presentation — a slide-by-slide walkthrough of the built-in Welcome to Eigendeck deck, showing how each slide was constructed.
• Building demos with LLMs — how to produce the interactive pieces.
• The elements & features reference — the building blocks (text, annotations, interactive elements, styles & fonts, watched assets, …).