A long time ago in a mental universe far far away I gave a talk to a theory seminar about quantum algorithms. An excerpt from the abstract:

Quantum computers can outperform their classical brethren at a variety of algorithmic tasks….[yadda yadda yadaa deleted]… This talk will assume no prior knowledge of quantum theory…

The other day I was looking at recent or forthcoming interesting quantum talks and I stumbled upon one by a living pontiff:

In this talk, I’ll describe connections between the unique games conjecture (or more precisely, the closely relatedly problem of small-set expansion) and the quantum separability problem… [amazing stuff deleted]…The talk will not assume any knowledge of quantum mechanics, or for that matter, of the unique games conjecture or the Lasserre hierarchy….

And another for a talk to kick off a program at the Simons institute on Hamiltonian complexity (looks totally fantastic, wish I could be a fly on the wall at that one!):

The title of this talk is the name of a program being hosted this semester at the Simons Institute for the Theory of Computing….[description of field of Hamiltonian complexity deleted…] No prior knowledge of quantum mechanics or quantum computation will be assumed.

Talks are tricky. Tailoring your talk to your audience is probably one of the trickier sub-trickinesses of giving a talk. But remind me again, why are we apologizing to theoretical computer scientists / mathematicians (which are likely the audiences for the three talks I linked to) for **their** ignorance of quantum theory? Imagine theoretical computer science talks coming along with a disclaimer, “no prior knowledge of the PCP theorem is assumed”, “no prior knowledge of polynomial-time approximation schemes is assumed”, etc. Why is it still considered necessary, decades after Shor’s algorithm and error correction showed that quantum computing is indeed a fascinating and important idea in computer science, to apologize to an audience for a large gap in their basic knowledge of the universe?

As a counter argument, I’d love to hear from a non-quantum computing person who was swayed to attend a talk because it said that no prior knowledge of quantum theory is assumed. Has that ever worked? (Or similar claims of a cross cultural prereq swaying you to bravely go where none of your kind has gone before.)

Dave, a few comments that I hope you will like:

1) “Imagine theoretical computer science talks coming along with a disclaimer, “no prior knowledge of the PCP theorem is assumed”, There is no need to imagine, many talks come with this disclaimer and certainly assuming (real) knowledge of the PCP theorem will leave out many CS people and even many CS theory people.

2) “why are we apologizing to theoretical computer scientists / mathematicians (which are likely the audiences for the three talks I linked to) for their ignorance of quantum theory?” This is not a very good way to look at the matter. Often you want to make the lecture self-contained to be on the same page with the audience in terms of notations and notions and not to gap some huge ignorance.

3) “I’d love to hear from a non-quantum computing person who was swayed to attend a talk because it said that no prior knowledge of quantum theory is assumed. Has that ever worked? (Or similar claims of a cross cultural prereq swaying you to bravely go where none of your kind has gone before.)”

There are many cases that when the abstract shows a real effort from the speaker in another field to make the lecture accessible for non experts this sway people to participate. (Of course, if there is a repeated tradition on not-delivering such promises this can be harmful.) Moreover, I like the talks in my own field to be on the self-contained side, and I am glad to see also things that I know. (And sometimes new angles on presenting them.)

4) My personal style is to make talks (and papers) as self-contained as possible. For example, usually when I give a talk about convex polytopes I defined what they are (a convex polytope is a convex hull of a finite set of points in a linear space.) The only exception I made was recently in a conference devoted solely to convex polytopes. I remember that when I wrote a paper to the 94 ICM I added in a footnote the explicit definition of a tensor product. The editor felt that I can safely assume that people know it already, and that it is a little inappropriate for a paper of the International Math Congress to include a definition of what a tensor product is, but I insisted on leaving it there. (Of course, I don’t necessarily advocate adopting such an extreme style on self-containingness.)

5) Actually, I remember a talk I gave at the IAS about my view on quantum fault tolerance where I devoted most of the time explaining what quantum computers are and what quantum fault tolerance is. At the end somebody came to me and said that he could not understand what my complaints against quantum computers are, but, for the first time, he could understand what quantum computation itself is. I regarded it as a great compliment.

As always Gil has successfully defeated all my arguments 🙂

Dave, let me mention that the thumb rule I have used (to be as self-contained as possible) like other thumb rules I developed over the years on related matters are inferior to the correct approach of giving it thought on a case-to-case basis.