The Trouble with Quantum Questions: Dialogue VII — On Uncertainty

Characters:

Professor Quillibrace

Mr Blottisham

Miss Elowen Stray

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Blottisham:

I object.

Quillibrace:

You always do. To what, today?

Blottisham:

Uncertainty. It’s sloppy.

Quillibrace:

Ah. A moral complaint.

Elowen Stray:

It does sound like ignorance dressed up as principle.

Blottisham:

Exactly! We just don’t know enough—so we make a law of it.

Quillibrace:

If only ignorance were so well behaved.

Blottisham:

You mean to tell me the universe forbids knowing both position and momentum?

Quillibrace:

I mean the universe refuses to be described as though those were jointly specifiable before a cut.

Blottisham:

There it is again—your cuts.

Quillibrace:

They keep turning up because you keep ignoring them.

Blottisham:

But surely the particle has a position and a momentum!

Quillibrace:

Surely according to whom?

Blottisham:

According to common sense!

Quillibrace:

A historically unreliable witness.

Elowen Stray:

So uncertainty isn’t about disturbance? About measurement messing things up?

Quillibrace:

No. That was an early attempt to preserve innocence.

Blottisham:

Then it’s intrinsic fuzziness?

Quillibrace:

No. That was an attempt to preserve drama.

Blottisham:

Then what is it?

Quillibrace:

Uncertainty is a limit on joint articulation, not a defect in reality.

Blottisham:

That’s far too tidy.

Quillibrace:

You prefer mess.

Blottisham:

I prefer knowing.

Quillibrace:

So does physics. It just insists on knowing carefully.

Elowen Stray:

So the problem isn’t that the particle is vague…

Quillibrace:

…it’s that we want incompatible precisions at once.

Blottisham:

Why incompatible?

Quillibrace:

Because they belong to different experimental cuts.

Blottisham:

You’re telling me precision has a price.

Quillibrace:

Precision always has a price. Classical physics simply hid the bill.

Elowen Stray:

So uncertainty isn’t a lack of control?

Quillibrace:

It’s a refusal to pretend control is absolute.

Blottisham:

That sounds philosophical.

Quillibrace:

It sounds accurate.

Blottisham:

But surely reality itself must be fully determinate!

Quillibrace:

Reality is fully adequate to what occurs. You’re asking it to be adequate to questions that have not yet been posed coherently.

Elowen Stray:

So uncertainty lives in the description?

Quillibrace:

In the constraints on description.

Blottisham:

You’re draining all the scandal out of it.

Quillibrace:

Scandal is expensive to maintain.

Blottisham:

Then Heisenberg wasn’t saying “you can’t know”?

Quillibrace:

He was saying “you can’t ask for everything at once.”

Blottisham:

That seems… reasonable.

Quillibrace:

Physics is full of such disappointments.

Elowen Stray:

So the trouble with uncertainty…

Quillibrace:

…is that we mistook epistemic humility for ontological failure.

Blottisham:

And accused the universe of carelessness.

Quillibrace:

When it was only insisting on discipline.

(A pause.)

Blottisham:

Let me see if I’ve learned anything at all.

Quillibrace:

A dangerous moment.

Blottisham:

Measurement wasn’t revelation.

The wavefunction wasn’t a thing.

Collapse wasn’t an event.

Superposition wasn’t multiplicity.

Entanglement wasn’t a bond.

Duality wasn’t contradiction.

And uncertainty isn’t ignorance.

Quillibrace:

You’ve ruined several lecture courses.

Elowen Stray:

So what is quantum theory, then?

Quillibrace:

A disciplined way of refusing bad questions.

Blottisham:

That’s it?

Quillibrace:

That’s more than enough.

Blottisham:

I feel strangely… calmer.

Quillibrace:

Understanding often has that effect.

Elowen Stray:

So the trouble with quantum questions…

Quillibrace:

…was never the answers.

Blottisham:

It was our insistence on asking too soon.

(Silence.)

Blottisham:

Very well. I concede defeat.

Quillibrace:

No need. You’ve simply changed games.

Blottisham:

Do I still get to complain?

Quillibrace:

Of course.

Blottisham:

Excellent. Then I am content.