Gravity from the
Quaternion Differential

Daniel Weidele
April 1, 2026
"What if electromagnetism and gravity come from the same equation?"

The Topology of Matter

Every particle is a different shape on the quaternion 3-sphere. Pick one to see what it looks like.

Choose a particle above
Select a particle to learn what it is
in the quaternion field theory.

1 The Idea

About 150 years ago, physicists rewrote the equations of electromagnetism. In the process, they threw away a piece — a scalar quantity that their math produced automatically. They called it a "gauge choice" and set it to zero.

That piece was gravity.

This thesis shows that if you keep that discarded scalar, you get a unified description of electromagnetism and gravity. Both forces emerge from a single mathematical object — the electromagnetic four-potential, written as a quaternion — and a single operation: taking its derivative.

The strength of both forces turns out to be determined by one number: 4, the dimension of the quaternion algebra. From this single integer, the theory predicts the fine structure constant (which governs electromagnetism) and the gravitational constant (which governs gravity) with extraordinary precision.

Bottom line: Electromagnetism and gravity aren't separate forces. They're two faces of the same quaternion equation — one visible at tree level, the other hidden behind a non-perturbative tunneling barrier.

2 One Object, One Operation

The object is the electromagnetic four-potential $\chi = (\phi, \mathbf{A})$. It's the same quantity every physicist already uses — the scalar potential $\phi$ (which makes electric fields) and the vector potential $\mathbf{A}$ (which makes magnetic fields) — just packaged as a quaternion instead of a four-vector.

The operation is the quaternion derivative $\nabla$. It's the familiar "take the rate of change" operator, but using the full quaternion multiplication rule instead of ordinary vector calculus.

The key difference: quaternion multiplication naturally produces both a scalar and a vector. Ordinary vector calculus only keeps the vector part. The scalar part is what got thrown away.

$\nabla \times \chi = \;?$

The quaternion derivative splits into two pieces:

Scalar part
$g = \dfrac{\partial\phi}{\partial t} - \nabla\!\cdot\!\mathbf{A}$
The hidden gravitational field
Vector part
$\mathbf{V} = -\mathbf{E} + \mathbf{B}$
The electromagnetic field

Applying $\nabla$ a second time gives the dynamics: the full field equation $\nabla\nabla\chi = 0$. When you set $g = 0$, you recover Maxwell's equations exactly. When you keep $g$, you get electromagnetism plus a gradient force — which is exactly the mathematical form of gravity.

3 The Hidden Scalar

The quantity $g = \partial\phi/\partial t - \nabla\!\cdot\!\mathbf{A}$ is called the Lorenz gauge condition in standard physics. For 150 years, physicists have set it to zero — treating it as a meaningless mathematical freedom, like choosing which direction is "north."

But the quaternion algebra produces $g$ on completely equal footing with the electric and magnetic fields. It's not optional — it's automatic. Discarding it is a choice, not a necessity.

Analogy: Imagine you have a machine that outputs three numbers every time you turn the crank: two useful ones and one "extra." For 150 years, everyone threw away the extra number. Turns out, it was encoding gravitational information the whole time.

In the full quaternion field equation $\nabla\nabla\chi = 0$, the scalar $g$ couples to the electromagnetic field $\mathbf{V}$ bidirectionally: electromagnetic configurations generate $g$, and $g$ exerts a gradient force (just like gravity) back on the dynamics. Setting $g = 0$ severs this coupling entirely.

4 Why No Classical Gravity?

Here's the puzzle: if $g$ is a real field, why don't we see gravity in the classical equations?

The answer is surprisingly clean. When you work out the quantum mechanics of the quaternion field (technically, the "Dirac bracket" of the constrained system), the scalar $g$ has no propagator. Its response to a source is purely local — a contact interaction, like bumping into something, rather than a long-range force like throwing a ball.

In plain terms: At the classical level, the gravitational channel $g$ is switched off. It exists as a degree of freedom, but it can't send signals across space. Gravity has to emerge through a different mechanism — a quantum one.

This is actually a feature, not a bug. It explains why gravity wasn't discovered in the quaternion formalism 150 years ago: classical analysis alone can't see it. You need the non-perturbative quantum structure of the theory.

5 The Octonion Emerges

There's a beautiful pattern in mathematics called the Cayley–Dickson construction: you can "double" number systems by pairing two numbers into one bigger number. Click the steps below to see how:

Real Numbers
1 dimension. Ordinary numbers on a line. Commutative and associative.
Complex Numbers
2 dimensions. Pair two reals: $a + bi$. Still commutative and associative. Unlocks 2D rotations.
Quaternions
4 dimensions. Pair two complex numbers. No longer commutative ($ab \neq ba$), but still associative. Encode 3D rotations and electromagnetism.
Octonions
8 dimensions. Pair two quaternions. No longer associative: $(ab)c \neq a(bc)$. This non-associativity is the source of gravity.

The thesis takes the four-potential $\chi$ (a quaternion) and its field $\nabla\chi$ (another quaternion) and pairs them into an octonion:

$\mathcal{O} = [\chi, \; \nabla\chi]$

No new fields are introduced — the octonion emerges from the four-potential interacting with itself through the derivative. It has 7 imaginary directions: 3 for the vector potential $\mathbf{A}$, 1 for the gravitational scalar $g$, and 3 for the electromagnetic field $\mathbf{V}$.

The key insight: Octonions are non-associative. The "associator" $(ab)c - a(bc)$ is generically nonzero and represents a genuine interaction that doesn't exist in the quaternion (or vector calculus) formulation. This interaction is gravity.

6 Everything from d = 4

Starting from just one number — $d = 4$, the dimension of the quaternion algebra — a cascade of geometric quantities follows. Hover over each row to see what it means:

QuantityFormulaValue
Quaternion dimension
The starting point: quaternions have 4 components
$d$4
Volume of $S^3$
The "surface area" of the 3-sphere that quaternions live on
$2\pi^2$19.74
Imaginary octonion directions
Doubling quaternions gives $2d - 1 = 7$ imaginary directions
$2d - 1$7
$G_2$ generators
The symmetry group of the octonions has 14 generators
$2(2d-1)$14
Active generators
One generator is frozen by the Cayley–Dickson structure, leaving 13
$4d - 3$13
Metric components
A symmetric rank-2 tensor in 4 dimensions has 10 independent entries
$d(d+1)/2$10
Tunneling exponent
Each metric component tunnels independently, each contributing $\alpha^2$
$d(d+1)$20

The gap equation determines the fine structure constant:

$\alpha(1 - \alpha)^2 = e^{-\pi^2/2}$

In words: the coupling constant equals a tunneling probability (the exponential) times a back-reaction factor. Solving this cubic equation gives $1/\alpha = 137.024$ — within 0.009% of the measured value.

The gravitational coupling then follows:

$\dfrac{G \, m_e^2}{k_e \, e^2} = \dfrac{\pi^2}{2} \cdot \dfrac{13}{49} \cdot \alpha^{20}$

Every number on the right comes from $d = 4$. The $\alpha^{20}$ factor is why gravity is so much weaker than electromagnetism: it takes 20 independent tunneling events to build a complete metric tensor.

7 The Predictions

The theory makes four testable predictions with no free parameters:

Fine Structure Constant (leading order)
137.024
Predicted
137.036
Measured
0.009% error
Fine Structure Constant (one-loop)
137.03597
Predicted
137.03597
Measured
0.3 parts per billion
Gravitational Constant G
6.67433
Predicted ($\times 10^{-11}$)
6.67430
Measured ($\times 10^{-11}$)
0.2σ of experimental uncertainty
Electron Mass
9.1181
Predicted ($\times 10^{-31}$ kg)
9.1094
Measured ($\times 10^{-31}$ kg)
0.10% error
Why gravity is weak: The ratio of gravitational to electromagnetic force between two electrons is about $10^{-43}$. In this theory, that's simply $\alpha^{20}$ — a small number raised to the 20th power. The exponent 20 counts the number of independent tunneling events needed to build a complete spacetime metric.

8 The Derivation Chain

The complete argument in five steps. Click any step to expand it:

1
Apply ∇ to χ → fields + scalar g
The quaternion derivative of the four-potential automatically produces the electromagnetic field and a scalar field $g$. This is pure quaternion algebra — no assumptions, no new physics. The scalar $g$ is the Lorenz gauge quantity that has been discarded since the 1880s.
2
The Dirac bracket kills g classically
Working out the constrained dynamics of the quaternion field, the scalar $g$ has zero propagator: it can't send long-range signals. At the classical level, there is no gravity. The constraint matrix turns out to be the quaternion multiplication matrix itself — a beautiful structural result.
3
χ and ∇χ form an octonion
The Cayley–Dickson construction pairs the four-potential with its derivative into an octonion: $\mathcal{O} = [\chi, \nabla\chi]$. No new fields are introduced. The gravitational scalar $g$ occupies one of seven imaginary octonionic directions, on equal algebraic footing with the electromagnetic components.
4
Non-associativity → independent tunneling
The octonionic associator generates interactions absent in the free quaternion theory. The Fano plane identity $M_{ab} = \delta_{ab}$ guarantees that each of the 10 metric tensor components tunnels independently through its own octonionic channel, giving a total suppression of $\alpha^{20}$.
5
Everything from d = 4
The prefactor $(\pi^2/2)(13/49)$, the exponent 20, and the gap equation for $\alpha$ all derive from a single integer: $d = \dim(\mathbb{H}) = 4$, the dimension of the quaternion algebra. No free parameters remain.

9 The Standard Model Connection

The octonion's symmetry group is $G_2$, a 14-dimensional group. It contains a remarkable chain of subgroups:

$G_2 \;\supset\; SU(3) \;\supset\; SU(2) \times U(1)$

This is exactly the Standard Model gauge group:

  • SU(3) — the strong force (quantum chromodynamics)
  • SU(2) — the weak force
  • U(1) — electromagnetism

The gravitational scalar $g$ picks out a preferred direction in the octonion, and the symmetry that stabilizes this direction is $SU(3)$. The Cayley–Dickson structure (the pairing of $\chi$ and $\nabla\chi$) provides the electroweak $SU(2) \times U(1)$ decomposition.

Particles as topological defects:

ParticleWhat it isChargeSpin
PhotonRipple in the EM field01
GravitonTunneled excitation via $g$02
ElectronWinding-1 defect in $\mathbf{A}$$-e$½
PositronWinding-(−1) defect in $\mathbf{A}$$+e$½
NeutrinoDefect in the $g$-direction0½
QuarkDefect in a color directionfractional½
GluonRipple in color directions01
HiggsFluctuation of $|\chi|$00

Bosons are waves (ripples). Fermions are topological knots (defects that can't unwind). The topology of $S^3$ gives them spin-½ and conserved charge.

Appendices

The thesis includes five appendices with detailed derivations. Click each to read a summary:

One-Loop Correction to the Gap Equation A

The leading-order gap equation gives $1/\alpha = 137.024$, which is off by 0.009%. This appendix computes the one-loop quantum correction from fluctuations around the $S^3$ instanton. Every ingredient — the fluctuation spectrum, the regularization, the zero-mode Jacobian — is determined by the geometry of $S^3$ and $d = 4$. The corrected value is $1/\alpha = 137.03597$, matching the measured value to 0.3 parts per billion. This is a factor of 30,000 improvement, with no free parameters introduced.

The Back-Reaction Factor $(1-\alpha)^2$ B

The gap equation contains a factor $(1-\alpha)^2$ that represents self-consistent back-reaction. This appendix derives it from two facts: (1) the effective metric is bilinear in the quaternion field (it has two "legs," each from a spacetime derivative), and (2) each leg independently draws its amplitude from the electromagnetic sector. Since the metric is rank-2, the available amplitude is $(1-\alpha)$ per leg, squared. The exponent 2 is exact — it's fixed by the rank of the tensor, not by a perturbative expansion.

Electron Mass from d = 4 C

The electron is identified as a degree-1 topological defect (a "knot") of the quaternion field on $S^3$. Its mass is set by a balance between kinetic energy (which favors spreading out) and the octonionic associator (which favors localization). Remarkably, the geometric prefactor cancels exactly due to self-consistency: the soliton lives on the same $S^3$ whose radius it determines. The result: $m_e = m_\text{Planck} \times \alpha^{21/2} \times$ (order-one factor), which predicts the electron mass to 0.10% accuracy.

The Two-Equation Form in Planck Units D

All dimensionful constants ($G$, $m_e$, $k_e$, $e$, $\hbar$, $c$) cancel from the gravitational coupling formula, leaving the entire theory as just two equations in two unknowns: the gap equation for $\alpha$ and a formula for $m_e^2$ in Planck units. One input ($d = 4$), two outputs. The hierarchy between gravity and electromagnetism is simply $\alpha^{21/2} \approx 4 \times 10^{-23}$ — large, but not mysterious.

The Topology of Matter E

Every Standard Model particle maps to a specific configuration of the quaternion field. Small oscillations are bosons (photons, gluons). Topological defects — configurations with nonzero winding number that can't unwind continuously — are fermions (electrons, quarks, neutrinos). The winding direction in the 7-dimensional octonion determines the quantum numbers: electromagnetic, gravitational, or color. The Higgs is a fluctuation in the magnitude of $\chi$, and a black hole is where the tunneling between sectors saturates to $\alpha \to 1$.