The Trouble with Quantum Questions: Dialogue IV — On Superposition

Characters:

Professor Quillibrace

Mr Blottisham

Miss Elowen Stray

---

Blottisham:

I’ve prepared myself for this one.

Quillibrace:

That already worries me.

Blottisham:

Superposition. Two states at once. Even you can’t wriggle out of that.

Quillibrace:

I’ve never wriggled in my life.

Elowen Stray:

It does sound straightforward. The particle is here and there.

Blottisham:

Exactly! At last, something delightfully paradoxical.

Quillibrace:

Paradoxes are usually bookkeeping errors with excellent publicity.

Blottisham:

There it is. The wriggle.

Quillibrace:

No. The receipt.

Blottisham:

Look—before measurement, the system is in a superposition of states. After measurement, it has one. That’s what the equations say.

Quillibrace:

The equations say what is admissible, not what is furnished.

Blottisham:

You really do enjoy ruining the furniture.

Quillibrace:

Only the imaginary pieces.

Elowen Stray:

So when we say “two states at once”, what’s wrong with that?

Quillibrace:

The “two”. And the “at once”. And the “states”.

Blottisham:

You’ve crossed the line into pedantry.

Quillibrace:

Pedantry is precision without purpose. This has a purpose.

Blottisham:

Fine. Explain superposition without subtraction.

Quillibrace:

Very well. Superposition is not multiplicity in reality; it is openness in specification.

Blottisham:

That’s not an explanation. That’s a slogan.

Quillibrace:

Then let’s try another. Superposition is the refusal of the theory to commit early.

Elowen Stray:

So nothing is actually doubled?

Quillibrace:

Nothing is instantiated twice, no.

Blottisham:

But the system contains multiple possibilities!

Quillibrace:

Contains is doing far too much work.

Blottisham:

They must be somewhere.

Quillibrace:

They are nowhere. They are allowable.

Blottisham:

You’re making possibility sound ghostly.

Quillibrace:

You keep trying to give it a body.

Elowen Stray:

Is superposition then just ignorance?

Quillibrace:

No. Ignorance presupposes a fact you lack. Superposition presupposes no such fact.

Blottisham:

That’s slippery.

Quillibrace:

That’s disciplined.

Blottisham:

When I toss a coin, it’s either heads or tails, even if I don’t know which.

Quillibrace:

Yes. And that’s precisely why coin tosses are not quantum systems.

Elowen Stray:

So before measurement, there isn’t a hidden answer?

Quillibrace:

There is no answer yet.

Blottisham:

Yet again you deny reality its privacy.

Quillibrace:

I deny it unnecessary secrets.

Blottisham:

Then what is superposition?

Quillibrace:

It is the theory speaking in the plural where the world has not yet spoken at all.

Elowen Stray:

So the plural belongs to the description?

Quillibrace:

To the constraint on description.

Blottisham:

Constraint sounds terribly limiting for something meant to be mysterious.

Quillibrace:

Mystery thrives on looseness. Physics does not.

Blottisham:

But the particle interferes with itself! Surely that means it’s in two places.

Quillibrace:

It means the conditions permit patterns that cannot be decomposed into single-path stories.

Blottisham:

That was evasive.

Quillibrace:

That was careful.

Elowen Stray:

So superposition isn’t a crowd inside the particle?

Quillibrace:

No more than a menu is a crowd inside a restaurant.

Blottisham:

You and your metaphors.

Quillibrace:

You and your counting.

Blottisham:

Then what collapses in superposition?

Quillibrace:

Nothing collapses in superposition. Superposition is what remains when collapse has not yet occurred.

Blottisham:

So it’s a waiting room?

Quillibrace:

No. Waiting implies time. This is logical openness, not temporal delay.

Elowen Stray:

So the system isn’t undecided.

Quillibrace:

The system is uncommitted.

Blottisham:

You make it sound like a shy guest.

Quillibrace:

It is a well-behaved theory.

(A pause.)

Blottisham:

Let me try again. Is the particle in two states at once?

Quillibrace:

No.

Blottisham:

Is it in one?

Quillibrace:

Not yet.

Blottisham:

Then where is it?

Quillibrace:

Wherever the instance places it.

Blottisham:

Which hasn’t happened.

Quillibrace:

Correct.

Blottisham:

So superposition is… nothing?

Quillibrace:

Superposition is the disciplined refusal to pretend something has happened when it hasn’t.

Elowen Stray:

That feels oddly reassuring.

Blottisham:

It feels like cheating.

Quillibrace:

Only if you wanted drama.

Blottisham:

I always want drama.

Quillibrace:

Physics is under no obligation to oblige you.

Blottisham:

Then the trouble with superposition…

Quillibrace:

…is that we mistook openness for multiplicity.

Elowen Stray:

And imagined crowds where there were only conditions.

Blottisham:

I suppose that does make it quieter.

Quillibrace:

Reality is often quieter than its metaphors.

(Silence.)

Blottisham:

Very well. I withdraw one particle from my imaginary menagerie.

Quillibrace:

A promising start.

The Trouble with Quantum Questions: Dialogue III — On Collapse

Characters:

Professor Quillibrace

Mr Blottisham

Miss Elowen Stray

---

Blottisham:

I refuse to let this one go.

Quillibrace:

You never do. It’s one of your more endearing qualities.

Blottisham:

Enough evasions. If the wavefunction isn’t a thing, and measurement isn’t a disturbance, then what—precisely—collapses?

Quillibrace:

Your expectations.

Blottisham:

I’m serious.

Quillibrace:

So am I.

Elowen Stray:

Collapse does sound violent. Something falling in on itself.

Blottisham:

Exactly! A rich field of possibilities suddenly reduced to one miserable fact. Surely that’s a loss.

Quillibrace:

Only if you mistake possibility for inventory.

Blottisham:

You can’t just wish away the others. They were there.

Quillibrace:

They were available.

Blottisham:

Which is the same thing!

Quillibrace:

Only if you think availability implies possession.

Elowen Stray:

So nothing disappears?

Quillibrace:

Nothing was ever present as an instance to disappear.

Blottisham:

Then why all this talk of collapse?

Quillibrace:

Because people imagined a thing where there was a constraint.

Blottisham:

You keep saying that as though it absolves everything.

Quillibrace:

It relocates everything.

Blottisham:

Collapse happens at a moment. Everyone agrees on that.

Quillibrace:

Everyone agrees on the grammar of the sentence.

Blottisham:

Don’t start with grammar again.

Quillibrace:

Very well. Let’s start with theatre.

Blottisham:

I fail to see—

Quillibrace:

A play affords many possible performances. On opening night, one is given. Have the others collapsed?

Blottisham:

That’s an analogy.

Quillibrace:

Yes. One with restraint.

Elowen Stray:

The other performances are still possible later.

Quillibrace:

Under different conditions.

Blottisham:

But the quantum case is final! Once measured, the system has a value.

Quillibrace:

For that instance.

Blottisham:

You keep saying that as though it softens the blow.

Quillibrace:

It removes the blow.

Elowen Stray:

So collapse isn’t something that happens to the system…

Quillibrace:

…it’s something that happens to the space of relevance.

Blottisham:

That’s terribly abstract.

Quillibrace:

Reality often is, until we force it into furniture.

Blottisham:

Let me be blunt. Before measurement, there are many possibilities. After measurement, only one remains. That’s collapse.

Quillibrace:

Before measurement, there is no “after” to compare it to.

Blottisham:

You’re dissolving time again.

Quillibrace:

No. I’m placing it where it belongs.

Elowen Stray:

In the instance?

Quillibrace:

Exactly.

Blottisham:

Then collapse has no duration?

Quillibrace:

No more than the present does.

Blottisham:

But physicists argue endlessly about when collapse occurs.

Quillibrace:

Because they are trying to time a category mistake.

Blottisham:

So there is no collapse event?

Quillibrace:

There is an instantiation.

Blottisham:

That’s just your word for it.

Quillibrace:

It’s a word that does less damage.

Elowen Stray:

So what feels like collapse is really the fact that we can no longer speak as if alternatives are open?

Quillibrace:

Yes. Speech tightens.

Blottisham:

That sounds disappointingly linguistic.

Quillibrace:

You introduced language the moment you said “state”.

Blottisham:

So collapse is about description, not reality?

Quillibrace:

It’s about which description can now do work.

Blottisham:

You’re saying nothing ontological changes.

Quillibrace:

Something ontological happens: a possibility becomes actual.

Blottisham:

And the others?

Quillibrace:

Remain possible in the theory—but irrelevant to the instance.

Blottisham:

Irrelevant sounds suspiciously like gone.

Quillibrace:

Irrelevant is kinder—and more accurate.

(A pause.)

Elowen Stray:

So collapse feels dramatic because we were attached to the unrealised possibilities.

Quillibrace:

Yes. We mourn what never happened.

Blottisham:

I do that all the time.

Quillibrace:

You see? Perfectly human. Entirely unnecessary in physics.

Blottisham:

Then the universe doesn’t constantly destroy futures.

Quillibrace:

It simply stops offering them here.

Blottisham:

That’s almost… polite.

Quillibrace:

Reality is impeccably well-mannered.

Elowen Stray:

So the trouble with collapse…

Quillibrace:

…is that we treated actuality as a loss instead of a specification.

Blottisham:

And insisted on asking when the loss occurred.

Quillibrace:

Rather than noticing that nothing was lost at all.

(Silence.)

Blottisham:

I must say, Professor, you’ve made collapse sound rather dull.

Quillibrace:

Dull things rarely keep philosophers awake at night.

Blottisham:

Yet somehow this will.

Quillibrace:

Then it is doing its job.

The Trouble with Quantum Questions: Dialogue II — On the Wavefunction

Characters:

Professor Quillibrace

Mr Blottisham

Miss Elowen Stray

---

Blottisham:

I’ve brought a diagram.

Quillibrace:

I feared as much.

Blottisham:

You’ll find it very helpful. A wavefunction, plotted nicely along an axis. Peaks here, troughs there. Quite elegant.

Quillibrace:

You’ve already drawn the wrong conclusion.

Blottisham:

I haven’t said a word!

Quillibrace:

You’ve drawn a picture.

Elowen Stray:

What’s the problem with picturing it?

Quillibrace:

Pictures insist on asking what it is a picture of.

Blottisham:

Of the system, obviously. Of where it is, or what it’s doing.

Quillibrace:

There we are again.

Blottisham:

The wavefunction describes the system’s state.

Quillibrace:

It encodes a rule.

Blottisham:

A rule for what?

Quillibrace:

For the distribution of possible instances.

Blottisham:

You’re evading the question.

Quillibrace:

I’m refusing the picture.

Elowen Stray:

So the wavefunction isn’t a wave?

Quillibrace:

It’s an unfortunate name.

Blottisham:

Then why does it interfere with itself?

Quillibrace:

Because probability spaces can have structure.

Blottisham:

That sounds suspiciously mathematical.

Quillibrace:

The wavefunction is mathematical.

Blottisham:

But mathematics represents something.

Quillibrace:

Sometimes. Sometimes it constrains.

Elowen Stray:

Constrains what can happen?

Quillibrace:

Constrains what counts as an outcome.

Blottisham:

Then the wavefunction exists in some abstract realm?

Quillibrace:

No.

Blottisham:

In physical space?

Quillibrace:

Also no.

Blottisham:

You’re being deliberately difficult.

Quillibrace:

I’m being ontologically tidy.

Elowen Stray:

So where is the wavefunction?

Quillibrace:

It isn’t.

Blottisham:

Outrageous.

Quillibrace:

It doesn’t need to be. It’s not the sort of thing that has a location.

Blottisham:

Then why do physicists talk about it “evolving”?

Quillibrace:

Because its constraints change with the system.

Blottisham:

Through time!

Quillibrace:

Through parameterisation.

Blottisham:

You’re just renaming time.

Quillibrace:

No. Time appears in instances, not in the theory of them.

Elowen Stray:

So the wavefunction doesn’t tell us what is happening now.

Quillibrace:

It tells us what could be made actual under different cuts.

Blottisham:

That sounds dangerously close to ignorance.

Quillibrace:

Ignorance has an owner. This does not.

Blottisham:

So it’s not a catalogue of unknown facts?

Quillibrace:

No facts are waiting.

Elowen Stray:

Then when people argue about whether the wavefunction is “real”…

Quillibrace:

—they are asking the wrong ontological question.

Blottisham:

Surely it must be either real or not.

Quillibrace:

Only if “real” means “thing-like”.

Blottisham:

Doesn’t it?

Quillibrace:

Not in a theory of instantiation.

Elowen Stray:

So the wavefunction is more like grammar than furniture?

Quillibrace:

A beautiful analogy.

Blottisham:

Grammar isn’t real.

Quillibrace:

Try violating it in public.

Blottisham:

That’s social convention.

Quillibrace:

And this is physical constraint.

Blottisham:

So the wavefunction tells reality how it may speak?

Quillibrace:

It tells us which utterances are available.

Elowen Stray:

And measurement chooses one utterance?

Quillibrace:

Actualises one.

Blottisham:

Then the wavefunction collapses?

Quillibrace:

No more than grammar collapses when you finish a sentence.

Blottisham:

But something changes.

Quillibrace:

Yes. The relevance of alternatives.

Blottisham:

You’re stripping all the drama out of it.

Quillibrace:

Drama is a sign of misplaced metaphysics.

Elowen Stray:

So the wavefunction doesn’t float around space.

Quillibrace:

It never did.

Blottisham:

Doesn’t split into worlds.

Quillibrace:

Only in bad novels.

Blottisham:

Doesn’t hide behind reality.

Quillibrace:

Reality has no backstage.

(A pause.)

Elowen Stray:

Then the real puzzle was why we expected the wavefunction to be a thing at all.

Quillibrace:

Because we are very fond of things.

Blottisham:

Even I must admit… this makes the arguments feel rather empty.

Quillibrace:

They were arguments about furniture in a grammar book.

Blottisham:

So the wavefunction isn’t a picture, or a wave, or a shadowy object.

Quillibrace:

It is a constraint on what may be actualised.

Blottisham:

Which exists—

Quillibrace:

—as a feature of the system-as-theory.

Elowen Stray:

And the trouble with the wavefunction…

Quillibrace:

…is that we keep asking what it is, instead of what it does.

Blottisham:

And what it does is—

Quillibrace:

—limit the ways reality can be made definite.

(Silence.)

Blottisham:

I shall have to redraw my diagram.

Quillibrace:

Or stop drawing altogether.

The Trouble with Quantum Questions: Dialogue I — On Measurement

Characters:

Professor Quillibrace

Mr Blottisham

Miss Elowen Stray

---

Blottisham:

Before we begin, I should like to register a complaint.

Quillibrace:

As ever, you are early.

Blottisham:

Quantum theory is perfectly intelligible until people like you interfere with it. Measurement is not mysterious. One measures a system, and the system responds.

Quillibrace:

Responds to what?

Blottisham:

To being measured.

Quillibrace:

Ah. The reflexive hammer.

Elowen Stray:

Is the mystery that measurement changes the system?

Blottisham:

Exactly! That’s the scandal. Before measurement, the system is in some indeterminate state. Then—bang!—measurement collapses it.

Quillibrace:

You say “before” very confidently.

Blottisham:

Time does tend to come before other times.

Quillibrace:

Only if you’ve already decided what sort of thing a system is.

Blottisham:

A physical thing, obviously.

Quillibrace:

With properties?

Blottisham:

Naturally.

Quillibrace:

Which it has—

Blottisham:

—whether or not we look, yes.

Quillibrace:

There it is.

Elowen Stray:

There what is?

Quillibrace:

The entire problem, fully assembled.

Blottisham:

Rubbish. I’ve merely stated common sense.

Quillibrace:

Common sense is an ontology that has forgotten it is one.

Blottisham:

Measurement reveals what is already there. If it didn’t, it wouldn’t be measurement.

Quillibrace:

You’re assuming measurement is a revelatory act.

Blottisham:

What else could it be?

Quillibrace:

An instantiating one.

Blottisham:

You’ve smuggled in your jargon already.

Quillibrace:

I’ve smuggled in nothing. You smuggled in persistence.

Elowen Stray:

Persistence of what?

Quillibrace:

Of determinate properties.

Blottisham:

Are you seriously suggesting the system has no properties before measurement?

Quillibrace:

I’m suggesting “before” is doing illicit work.

Blottisham:

The system exists before we measure it!

Quillibrace:

The system—as a theory of possible outcomes—yes.

Blottisham:

That’s evasive.

Quillibrace:

No. It’s specific.

Elowen Stray:

So when physicists talk about a system being “in superposition” before measurement—

Quillibrace:

—they are talking about a structured space of possibility.

Blottisham:

Then why not say that?

Quillibrace:

Because everyone keeps trying to picture it.

Blottisham:

Pictures are helpful.

Quillibrace:

Only when they picture the right kind of thing.

Blottisham:

And measurement turns this… possibility-space… into a fact?

Quillibrace:

Into an instance.

Blottisham:

At a moment in time.

Quillibrace:

As a perspectival cut.

Blottisham:

That’s just collapse with extra syllables.

Quillibrace:

Collapse suggests destruction. Nothing is destroyed.

Blottisham:

Something must be lost! All those other possibilities vanish.

Quillibrace:

They cease to be relevant to this instance.

Elowen Stray:

So measurement isn’t violence—it’s selection?

Quillibrace:

Selection is closer. But even that suggests choosing from a shelf.

Blottisham:

Isn’t that what experiments do?

Quillibrace:

No. Experiments actualise one trajectory through a system’s potential.

Blottisham:

You make it sound as though the system was waiting.

Quillibrace:

Waiting implies time. The system does not wait. It affords.

Blottisham:

Affords what?

Quillibrace:

Different possible instances under different cuts.

Elowen Stray:

So measurement doesn’t answer a question we asked earlier.

Quillibrace:

It poses a question in a very particular way.

Blottisham:

Then the observer really does matter!

Quillibrace:

The setup matters.

Blottisham:

You’re dodging consciousness now.

Quillibrace:

I’m refusing it entry.

Blottisham:

But surely the mystery is why observation changes the system.

Quillibrace:

Observation doesn’t change the system.

Blottisham:

Everyone says it does!

Quillibrace:

Everyone is still treating the system as a thing with hidden furniture.

Elowen Stray:

Then what changes?

Quillibrace:

Which instance is actualised.

Blottisham:

From what?

Quillibrace:

From the system-as-theory.

Blottisham:

So nothing “happens” to the wavefunction?

Quillibrace:

The wavefunction was never a thing to begin with.

Blottisham:

Then why all the fuss?

Quillibrace:

Because people keep asking when properties appear, instead of what kind of object they think properties belong to.

(A pause.)

Elowen Stray:

So the measurement problem isn’t a physical problem at all.

Quillibrace:

It’s an ontological hangover.

Blottisham:

You’re saying we sobered up too late.

Quillibrace:

I’m saying we keep ordering another round.

Blottisham:

Then measurement doesn’t disturb reality.

Quillibrace:

It is the moment at which reality is specified.

Blottisham:

That sounds final.

Quillibrace:

Only for that instance.

Elowen Stray:

And the system remains?

Quillibrace:

As structured potential. Always.

Blottisham:

I don’t like this at all.

Quillibrace:

Of course not. It means measurement was never a magic act—just a badly framed question.

Blottisham:

Then the mystery evaporates.

Quillibrace:

Yes.

Blottisham:

Leaving only—

Quillibrace:

—the work of saying clearly what kind of thing we are talking about.

(A silence.)

Elowen Stray:

So the trouble with measurement…

Quillibrace:

…is that we expected it to reveal what was already there.

Blottisham:

And instead—

Quillibrace:

—it tells us what has just been made actual.

Three Ways of Missing the Point: Dialogue V — On What One Is Doing When One Reads This

Characters:

Professor Quillibrace

Mr Blottisham

Miss Elowen Stray

---

Blottisham:

I’ve become uneasy.

Quillibrace:

You say that as though it were new.

Blottisham:

Up to now, at least we were discussing things out there. Meaning. Wrongness. Theory. But I’ve begun to suspect—

Quillibrace:

—That you are implicated?

Blottisham:

That someone else is listening.

(A pause.)

Elowen Stray:

Listening where?

Blottisham:

Here. Now. Us. This conversation.

Quillibrace:

Oh good. You’ve noticed.

Blottisham:

You didn’t think to mention it?

Quillibrace:

I thought it sporting to see who would flinch first.

Elowen Stray:

So when someone reads this—

Quillibrace:

—They are not observing.

Blottisham:

They’re judging!

Quillibrace:

Worse. They’re participating.

Blottisham:

That’s outrageous. They haven’t said a word.

Quillibrace:

Neither does a match, until struck.

Elowen Stray:

When I read something carefully, I can feel myself leaning. Agreeing. Resisting. Sometimes rehearsing objections.

Blottisham:

Which proves my point! They’re evaluating correctness.

Quillibrace:

They’re rehearsing positions.

Blottisham:

Same thing.

Quillibrace:

Not at all. Evaluation assumes a fixed target. Rehearsal assumes future use.

Elowen Stray:

So reading isn’t consumption—it’s preparation?

Quillibrace:

Or calibration.

Blottisham:

Calibration to what?

Quillibrace:

To what the reader might say next, elsewhere, to someone who isn’t here.

Blottisham:

That seems… indirect.

Quillibrace:

Meaning always is.

Elowen Stray:

Then the reader isn’t trying to extract a message.

Quillibrace:

They’re testing a stance.

Blottisham:

Against what?

Quillibrace:

Against themselves.

Blottisham:

That sounds uncomfortably introspective.

Quillibrace:

Only if you believe the self is a private object.

Elowen Stray:

When I read something that unsettles me, I often argue with it silently.

Blottisham:

As one should.

Quillibrace:

And in doing so, you discover which assumptions rush to your defence.

Elowen Stray:

Yes. Some of them surprise me.

Blottisham:

So the reader is being diagnosed now?

Quillibrace:

No. The reader is diagnosing the text.

Blottisham:

You just said—

Quillibrace:

—and in doing so, reveals the instruments they brought.

Blottisham:

This is turning into a parlour trick.

Quillibrace:

All reflexivity looks like a trick until you notice it keeps working.

Elowen Stray:

So when I agree with you, Professor, that’s also meaningful?

Quillibrace:

Especially then.

Blottisham:

Because agreement can be lazy.

Quillibrace:

Or revealing.

Elowen Stray:

And when I disagree?

Quillibrace:

Then meaning sharpens.

Blottisham:

So the reader can’t win.

Quillibrace:

On the contrary. The reader cannot avoid playing.

(Another pause.)

Blottisham:

I object to being part of someone else’s experiment.

Quillibrace:

You object to it every time you read, too.

Blottisham:

Nonsense.

Quillibrace:

When you read, you supply tone, emphasis, patience, irritation. None of that is in the ink.

Elowen Stray:

So reading is an act of completion?

Quillibrace:

Of actualisation.

Blottisham:

Then the meaning of this dialogue isn’t settled yet.

Quillibrace:

It never will be.

Blottisham:

Even after the last word?

Quillibrace:

Especially then.

Elowen Stray:

Because that’s when the reader has to carry it somewhere else.

Quillibrace:

Yes. Into another conversation. Another silence. Another risk.

Blottisham:

I don’t care for this at all.

Quillibrace:

You’re reading it very well.

Blottisham:

Then let me ask them something.

Quillibrace:

Be my guest.

Blottisham:

What exactly do you think you’re doing right now?

(A longer pause.)

Elowen Stray:

Perhaps the better question is: what might they now find harder not to do?

Quillibrace:

Precisely.

Blottisham:

This is entrapment.

Quillibrace:

No. It’s an invitation with consequences.

Elowen Stray:

So reading isn’t passive.

Quillibrace:

It’s a rehearsal for responsibility.

Blottisham:

I preferred it when texts just meant things.

Quillibrace:

They still do.

Blottisham:

Without asking anything of me?

Quillibrace:

Ah. No.

(A final pause.)

Elowen Stray:

Then perhaps the question isn’t whether the reader understands this.

Quillibrace:

But whether they will notice where it next appears.

Blottisham:

In their own mouth.

Quillibrace:

Or their restraint.

Elowen Stray:

Or the moment they choose not to speak.

Blottisham:

You’ve ruined reading for me.

Quillibrace:

You’re welcome.