We began this investigation with what seemed like a straightforward question:
What are we trying to quantise?
The question turned out to be less straightforward than expected.
We discovered that the thing we assumed we were trying to quantise—spacetime—might not be a fundamental thing at all.
We then discovered that gravity itself might not be a thing.
And as we pursued the implications, the relationship between quantum theory and general relativity began to look rather different.
Perhaps the problem is not that we have two fundamentally incompatible theories.
Perhaps the problem is that we have mistaken two extraordinarily successful descriptions for two fundamental ontologies.
If so, we have spent decades asking how to combine them when the more fundamental question is:
What makes both descriptions possible?
That is a rather different question.
And perhaps it is the question we should have been asking all along.
The journey so far
Let us briefly reconstruct the path.
We began with quantum theory.
The wavefunction, we suggested, need not be regarded as a physical object inhabiting some hidden quantum space.
It can instead be understood as a description of structured potential.
A wavefunction tells us what actualisations are possible and how those possibilities are related.
The particle, in this ontology, is not a little thing already sitting inside the wavefunction.
It is an actual instance of potential.
The analogy with climate proved useful.
Climate is not a particular weather event.
It is a structured description of possible weather patterns.
Weather is what actually happens.
Likewise:
wavefunction → potentialparticle/event → actualisation
This gave us a way of thinking about quantum theory without making the wavefunction into a thing.
Then came geometry
We turned to general relativity.
Here the familiar temptation is to imagine spacetime as a physical arena that bends.
But our relational ontology suggested another interpretation.
What is physically observable are relations among physical processes:
- spatial intervals;
- temporal intervals;
- trajectories;
- clock rates;
- causal connections;
- relative accelerations.
Geometry provides a remarkably powerful way of describing the stable structure of those relations.
It need not therefore be fundamental.
We can say:
geometry describes relations without being a substance composed of relations.
This was the decisive shift.
Spacetime ceased to be the container in which physical reality happens.
It became a description of how physical reality is organised.
Gravity followed
Once geometry ceased to be fundamental, gravity had to be reconsidered.
We found that we did not need a gravitational thing.
Nor did we need to restore Newton's force.
Gravity could instead be understood as a systematic relational pattern.
Mass-energy is associated with particular changes in spatial and temporal relations.
Free bodies follow geodesics within that relational structure.
Tidal effects describe systematic differences among neighbouring trajectories.
The metric encodes these regularities.
The curvature describes how those relational structures vary.
Gravity is therefore real.
But its reality need not be the reality of a substance.
Gravity can be a real pattern without being a gravitational thing.
This is perhaps the most important ontological distinction in the entire investigation.
And then the two theories met
At this point, the usual quantum-gravity problem began to look peculiar.
If quantum theory describes potential and actualisation, while general relativity describes emergent relational geometry, why should we expect to quantise the geometry?
Why should we expect the metric to be a fundamental quantum variable?
Why should we expect gravity to possess fundamental quantum constituents?
Perhaps these questions make sense only if we have already assumed that geometry and gravity are fundamental.
But that is precisely what we have questioned.
The alternative is more radical:
Quantum theory may describe the underlying relational dynamics, while general relativity describes the stable large-scale geometry that emerges from them.
If that is right, then quantum gravity is not the fundamental theory we have been searching for.
It is a signpost pointing toward a deeper theory.
Not two worlds
This does not mean that quantum theory describes one world and general relativity another.
There is one world.
There are different descriptions of it.
That distinction matters.
A map and a landscape are not competing landscapes.
A weather map and a climate model do not describe two different atmospheres.
A molecular description and a thermodynamic description do not describe two different fluids.
They capture different regularities at different scales and levels of organisation.
Perhaps quantum theory and general relativity should be understood in the same way.
The fundamental problem is therefore not:
How can we make the two descriptions identical?
It is:
What is the relationship between the levels they describe?
Ontology before unification
This suggests a methodological principle.
Before attempting to unify theories, we should ask:
What kind of thing—or relation—is each theory actually describing?
This sounds obvious.
It is not.
Physics has an understandable tendency to treat successful mathematical variables as though they must correspond directly to fundamental entities.
The metric becomes spacetime.
The wavefunction becomes a quantum object.
The field becomes a physical substance.
Information becomes a conserved thing.
The mathematical description acquires an ontology.
And once that happens, the problem of unification becomes the problem of reconciling the entities we have created.
Perhaps some of the hardest problems in fundamental physics are therefore problems of premature ontology.
The strange case of the noun
There is something almost comical about the process.
A process becomes a pattern.
We give the pattern a noun.
The noun becomes an object.
The object is assigned properties.
Then we ask what the object is made of.
Physics is not uniquely guilty of this.
Human thought does it constantly.
But physics is particularly powerful at turning abstractions into mathematically precise objects.
That is both its strength and its danger.
A mathematical object can be extraordinarily useful without being a fundamental constituent of reality.
The metric tensor is real as mathematics.
It is real as a physical description.
But neither fact entails that the universe is fundamentally made of metric tensors.
The wavefunction is real as a mathematical representation of quantum potential.
That does not entail that the universe contains wavefunction-stuff.
The distinction is subtle.
It is also crucial.
What, then, is fundamental?
At this point we should be cautious.
Our investigation has repeatedly used the word relational.
But relational ontology does not mean that we have simply replaced “things” with “relations” and declared relations to be the new fundamental substance.
That would merely repeat the same mistake.
A relation is not necessarily something that exists independently between already-existing objects.
Relations may be constitutive.
An actual physical entity may be what it is partly because of the relations in which it participates.
The fundamental level may therefore not consist of objects connected by relations.
It may consist of relational processes from which objects become identifiable.
This is a much more radical possibility.
Potential before object
Our quantum analysis points in this direction.
If the wavefunction represents potential, then the fundamental description is not initially a catalogue of fully determinate objects.
It is a structured space of possibilities.
Actualisation produces distinctions.
Distinctions establish relations.
Relations can stabilise.
Stable relational patterns become recognisable as objects, systems, particles and fields.
The order of explanation is therefore reversed.
We normally imagine:
things exist → things interact → relations arise.
Our ontology suggests:
potential relations → actualisation → stable relations → things become identifiable.
The “thing” is not eliminated.
It is decentred.
It becomes a relatively stable achievement of relational organisation.
Reality becomes structured
This also changes what we mean by emergence.
Emergence is sometimes portrayed as though reality mysteriously acquires new properties at larger scales.
But if our ontology is right, emergence is not magic.
It is the stabilisation of relational patterns.
A particle is a stable pattern.
An atom is a stable pattern.
A molecule is a stable pattern.
A living organism is a vastly more complicated stable pattern.
A measuring apparatus is a stable pattern.
A classical object is a stable pattern.
A gravitational geometry may be a stable pattern of an even larger order.
Reality does not need to manufacture new substances at every level.
It can organise itself into increasingly stable regimes.
Geometry as one such regime
Geometry then becomes one of the great achievements of physical organisation.
At sufficiently large scales, the relations among physical processes become sufficiently regular that we can describe them using:
- distance;
- duration;
- angle;
- causal order;
- curvature.
The metric becomes meaningful.
Geodesics become meaningful.
Spacetime becomes a powerful effective description.
And Einstein's equations become the dynamical laws of that regime.
This does not diminish general relativity.
Quite the contrary.
It tells us why an apparently simple geometric theory can describe such an enormous range of physical phenomena.
Its simplicity may be the simplicity of an emergent universal structure.
Why the universe looks geometric
This now becomes one of the great questions.
Why does the macroscopic world admit such an elegant geometric description?
Our answer cannot yet be complete.
But the direction is clear.
Perhaps geometry is what stable relational organisation looks like from the macroscopic level.
Perhaps the smoothness of spacetime reflects the enormous redundancy of microscopic possibilities.
Perhaps many different underlying configurations converge upon the same effective geometry.
Perhaps geometric concepts are therefore robust precisely because the microscopic details cease to matter.
If so, the apparent fundamentality of spacetime would be a consequence of its extraordinary stability.
That would explain something important.
The fact that a description is universal does not make it fundamental.
It may make it emergent and inevitable.
The role of information
Our earlier discussion of information also returns here.
Information is not a mysterious substance flowing through the universe.
It concerns distinctions, correlations and the structure of what can be known or inferred.
At the fundamental level, actualisation establishes distinctions.
Correlations preserve relations among those distinctions.
Stable structures can therefore carry information.
As relational organisation becomes increasingly robust, information becomes encoded in persistent physical patterns.
This gives us a natural bridge from quantum potential to classical information.
The classical world is full of records.
A photograph.
A fossil.
A memory.
A measuring instrument.
A written equation.
A star's spectrum.
Each is a stable physical correlation.
The world becomes, in a profound sense, informationally legible because its relational structures become stable enough to preserve distinctions.
Perhaps classical reality is the great emergence
We have therefore arrived at something larger than the quantum-gravity problem.
The real mystery may not be:
Why is gravity difficult to quantise?
It may be:
Why does the world become classical at all?
Why do we find persistent objects?
Why do macroscopic events become effectively definite?
Why do causal relations become stable?
Why does geometry become smooth?
Why does time acquire the practical structure of clocks and histories?
Why can observers construct a common world?
These questions belong together.
They concern the emergence of a world in which classical concepts become reliable.
Quantum theory would then describe the underlying potentiality.
Classical reality would describe the stable actuality produced through enormous networks of relations.
General relativity would describe one of the deepest organisational structures of that actuality.
The arrow of explanation
The explanatory arrow therefore points in one direction.
Not:
classical world → quantised geometry → quantum gravity
but:
potential → actualisation → relational organisation → stable structures → classical world → geometry
This is not yet a physical derivation.
But it is a radically different research programme.
And perhaps it is the research programme that quantum gravity has been indirectly asking us to formulate.
What would the fundamental theory contain?
We can now ask the question directly.
Suppose we wanted to construct the deeper theory.
What would we expect it to contain?
Probably not spacetime as a primitive.
Probably not a metric as a primitive.
Probably not gravity as a primitive.
Perhaps not even particles.
Instead, we might expect some structure governing:
- possible relations;
- actualisation;
- correlation;
- persistence;
- constraint;
- composition;
- and transformation.
The theory would need to explain how these processes generate effective structures with the properties we currently associate with quantum systems and geometry.
In particular, it would need to explain why certain relational organisations are stable.
Because stability is the key.
Without stability, there are no objects.
Without persistent correlations, there is no information.
Without stable causal organisation, there is no classical world.
Without sufficiently regular relational intervals, there is no geometry.
The deepest physical question may be stability
This gives us an intriguing reinterpretation of physics.
Perhaps the fundamental question is not:
What are the ultimate things?
but:
What kinds of relational organisation can persist?
This would bring our ontology very close to the idea of affordance.
Reality does not merely contain possibilities.
It contains structures that make some possibilities more stable, more probable, or more accessible than others.
Some configurations disappear immediately.
Others persist.
Some relations reinforce themselves.
Others dissolve.
Some patterns become capable of supporting further patterns.
Over time, an extraordinarily rich hierarchy of stable organisation can emerge.
The universe would then not merely be a collection of things.
It would be an ecology of becoming.
The furrow and the plough
And here we return, perhaps unexpectedly, to the metaphor that has accompanied some of our thinking.
The furrow may guide the plough.
Once a path has been established, subsequent motion is not arbitrary.
The existing structure affords certain continuations more readily than others.
In our present context, this becomes an ontological principle.
The actual past establishes relations.
Those relations constrain future possibilities.
The resulting structure makes some developments more probable or accessible than others.
The future is not simply predetermined.
But neither is it unconstrained.
Reality acquires a history of affordances.
Perhaps this is one way to understand how order can emerge without requiring an external designer or a fundamental deterministic mechanism.
The world becomes structured by what has already become actual.
From possibility to history
This gives us a different conception of physical history.
History is not merely a sequence of states.
Each actualisation changes the relational context in which subsequent actualisations occur.
An event therefore does not simply happen in reality.
It contributes to what reality can subsequently become.
This is why potential and actuality belong together.
Potential without actualisation would remain merely possibility.
Actuality without potential would have no future.
Reality is the continual transformation between them.
And stable structures emerge because some patterns of actualisation are capable of sustaining themselves.
Why mathematics works
There is another consequence.
Why is mathematics so extraordinarily effective in physics?
The relational ontology offers a possible answer.
Mathematics is exceptionally good at representing invariant structure.
When physical relations stabilise, they become mathematically describable.
Geometry captures invariant relations among intervals.
Group theory captures invariant transformations.
Probability captures structured possibility.
Information theory captures relations among distinctions and correlations.
Differential equations capture lawful patterns of change.
Physics succeeds because mathematics is exquisitely suited to describing the structures that survive changes of description.
The effectiveness of mathematics may therefore be less mysterious than it first appears.
We are not necessarily discovering that reality is “made of mathematics”.
We may be discovering that stable relational structure is mathematically expressible.
What becomes of unification?
We can now return to the dream of a unified theory.
Perhaps unification has been understood too narrowly.
We have tended to imagine unification as finding one equation from which all existing theories can be derived.
But perhaps the deeper unity is ontological rather than algebraic.
A unified account would explain why different mathematical descriptions become appropriate at different levels.
It would show how:
quantum potentialbecomesactual events,
how:
actual eventsbecomestable relations,
how:
stable relationsbecomeeffective classical systems,
and how:
effective classical systemsacquiregeometric organisation.
Such a theory might not make quantum mechanics and general relativity look identical.
It would explain why they should not look identical.
That would be a deeper form of unification.
And perhaps this is what “quantum gravity” was trying to tell us
Seen in this light, the extraordinary difficulty of quantum gravity becomes philosophically interesting.
Perhaps nature was not refusing to give us the answer.
Perhaps the difficulty was telling us that the question was malformed.
Every attempt to quantise spacetime runs into conceptual trouble.
Every attempt to preserve the familiar ontology produces tensions between quantum theory and general relativity.
Perhaps this is not merely a technical obstacle.
Perhaps it is a clue.
The failure may be instructive because it repeatedly exposes the same assumption:
that the effective geometric description must itself be fundamental.
If that assumption is false, then the problem disappears in a rather peculiar way.
We do not solve quantum gravity.
We dissolve the need for it as a fundamental theory.
But this is not a victory lap
We should be careful here.
It would be very easy to turn this conclusion into another metaphysical certainty.
We should not.
We have not demonstrated that spacetime is emergent.
We have not derived gravity from quantum potential.
We have not produced a new fundamental equation.
We have not solved quantum theory.
We have not shown that every apparent paradox in physics is merely an ontological mistake.
What we have done is more modest.
We have asked whether the conceptual order of explanation might be wrong.
And we have found that a relational ontology makes a striking amount of sense of the resulting landscape.
That is enough to justify further investigation.
The experimental question remains
Ultimately, physics must return to experiment.
A relational ontology cannot exempt itself from empirical constraint.
If the ontology is to become physics, it must generate consequences.
It must tell us:
- what structures should exist;
- what behaviours should occur;
- what approximations produce known theories;
- where deviations might appear;
- and what observations could distinguish it from competing accounts.
This is where philosophy must eventually hand the problem back to physics.
But perhaps philosophy can improve the question that physics asks.
That may be its proper role here.
What are we actually looking for?
We can finally answer the question with which this essay began.
We are probably not looking for:
- a quantum particle of spacetime;
- a fundamental gravitational substance;
- a microscopic metric;
- or a single theory in which quantum mechanics and general relativity are simply pasted together.
We are looking for something more fundamental.
Something capable of explaining why potential becomes actuality, why actuality becomes relational structure, why relational structure becomes stable organisation, and why sufficiently stable organisation appears to us as a classical geometric world.
Perhaps the fundamental theory will not describe things at all.
Perhaps it will describe becoming.
A possible ontology of becoming
If we had to compress the whole investigation into one sequence, it might now look like this:
Potential→ possibilities structured by relationsActualisation→ a determinate event occursRelation→ the event changes the relational situationCorrelation→ distinctions become connected across systemsPersistence→ some patterns remain stableObject→ a persistent relational pattern becomes identifiable as a thingInformation→ stable distinctions and correlations become recordableClassicality→ sufficiently robust patterns behave as definite systemsGeometry→ stable relations acquire an effective metric descriptionGravity→ systematic constraints on physical becoming emerge from that geometry.
Again, this is not a completed physical theory.
It is an ontological map.
But perhaps maps are useful precisely because they show where we have not yet travelled.
Beyond quantum gravity
The title of this series can now be read in two senses.
“Beyond quantum gravity” does not mean beyond quantum theory.
It does not mean beyond general relativity.
And it certainly does not mean that either theory should simply be discarded.
It means going beneath the ontological assumptions that make quantum gravity appear to be the inevitable destination.
Once we do that, the landscape changes.
The wavefunction need not be a thing.
Spacetime need not be a thing.
Gravity need not be a thing.
Information need not be a thing.
Particles need not be fundamental things.
Yet all of these can remain completely real as patterns, descriptions, relations, actualisations and structures.
The world does not become less real when we stop turning its descriptions into substances.
Perhaps it becomes more intelligible.
The possibility that there was never a problem
And now we can return to our starting suspicion.
Perhaps the apparent conflict between quantum theory and general relativity is partly produced by the ontology through which we interpret them.
Quantum theory is interpreted as describing things in spacetime.
General relativity is interpreted as describing the spacetime in which those things exist.
We then discover that the two pictures cannot be made simultaneously fundamental.
Perhaps that is because neither side is describing the world at the level we assumed.
Quantum theory describes structured potential and actualisation.
General relativity describes emergent relational geometry.
The apparent contradiction may therefore be the consequence of trying to make two different descriptions answer the same ontological question.
The paradox was generated by the question.
Perhaps there is no final level
There is one final possibility worth leaving open.
Perhaps even our search for a fundamental relational ontology contains the same mistake.
Perhaps there is no final layer of reality at which we discover the ultimate things.
Perhaps each apparent foundation turns out to be a pattern within a deeper relational structure.
If so, “fundamental” may not mean:
the final substance from which everything else is made.
It may mean:
the level at which our current explanatory distinctions cease to be useful.
That would make ontology less like digging down to bedrock and more like discovering increasingly deep forms of organisation.
Perhaps reality has no bottom in the sense we imagined.
Perhaps it has depth.
The real lesson
This investigation began as an inquiry into black holes and quantum gravity.
It has ended somewhere much larger.
We have been led to question the assumption that reality is fundamentally composed of independently existing things.
In its place we have found a possibility:
Reality may be fundamentally relational and processual.
Potential becomes actual.
Actuality establishes relations.
Relations stabilise.
Stable relations become recognisable as things.
Things participate in larger organisations.
Larger organisations acquire effective descriptions.
Some of those descriptions become geometry.
And geometry gives us gravity.
At no point do we need to introduce a mysterious gravitational substance, a fundamental spacetime container, or a quantum version of either.
The world does not have to be assembled from things.
It may become structured.
And so, what are we actually looking for?
Perhaps the answer is now surprisingly simple.
We are looking for an account of how reality becomes organised.
Not an inventory of ultimate objects.
Not a quantum theory of spacetime.
Not a gravitational particle.
Not a final noun.
We are looking for the dynamics by which:
possibility becomes actuality,actuality becomes relation,relation becomes stability,stability becomes structure,and structure becomes the world we recognise.
If such an account could be developed into a physical theory, it might explain not merely quantum mechanics or gravity, but why both are possible.
And that would be a rather different kind of theory of everything.
It would not tell us what everything is made of.
It would tell us how a world comes to have things in it at all.
Perhaps that is the deeper question.
And perhaps, once we finally ask it, the old question—
How do we quantise gravity?
—will begin to look rather like asking how to quantise the weather.
The weather is real.
The climate is real.
The relations are real.
The patterns are real.
But none of them needs to be a thing.
And perhaps gravity is like that too.
Perhaps spacetime is like that too.
Perhaps the classical world itself is like that.
And perhaps the most profound lesson of the entire investigation is simply this:
Reality need not be made of things in order for things to be real.
🍷🙂