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INTERACTIVE EXPLANATION

Explore ordinary phase and the quarter-turn operator

A real quarter-turn can act as multiplication by the ordinary imaginary unit. Move the angle and inspect the vector, its quarter-turn, and its reversal.

Updated 4 minutes to read

The central connection

The operator J(x,y)=(−y,x) satisfies J²=−I and preserves the Euclidean norm. Its exponential gives circular phase, which differs from the split-complex unit used for hyperbolic pairing.

Try the demonstration

Explore the example

Use the sliders with a pointer, or focus a slider and use the arrow keys. Home and End select its limits. All values are model inputs.

θ = 45°. ψ = (0.7071, 0.7071); Jψ = (-0.7071, 0.7071); J²ψ = (-0.7071, -0.7071). Squared norm = 1. This is ordinary circular phase, J² = −I.

Circular phase and two quarter turnsThe original vector is rotated 45 degrees. Applying J gives a quarter turn; applying it twice reverses the vector.xyDark: ψ · Gold: Jψ · Grey: J²ψ = −ψ

Exact real-plane rotation and operator identities. The demonstration does not derive a probability rule, action scale, physical clock, or Lorentzian spacetime.

Rotate the phase vector

The slider sets an angle θ in degrees between zero and one full turn. The dark segment represents ψ=(cosθ,sinθ). The gold segment represents Jψ, and the grey segment represents J²ψ. All endpoints lie on the same unit circle. The summary reports their components and the squared norm.

The angle is a dimensionless phase parameter, not a measured time. Calling the circle an inner recurrence would additionally require a source update, a physical phase rate, and a rule connecting the carrier to completed observations.

Derive the quarter-turn identity

Define J(x,y)=(−y,x). Applying it again gives J(−y,x)=(−x,−y), so J²=−I. Its transpose is −J, and JᵀJ=I; therefore it preserves x²+y².

J²=−I,   exp(θJ)=cosθ I+sinθ J.

The exponential identity follows by grouping even and odd powers in its series. This reconstructs an ordinary complex scalar convention on the real plane: multiplication by a+ib acts as aI+bJ. It does not require adding a third coordinate to represent the imaginary unit.

Read a forty-five-degree example

At θ=45°, ψ=(1/√2,1/√2). Its quarter-turn is (−1/√2,1/√2), and applying J twice gives (−1/√2,−1/√2). Each vector has squared norm one. At θ=360°, the original vector returns to (1,0), although the slider records that a complete turn was performed.

A circular display by itself cannot count how many complete turns occurred. A clock based on this phase needs an unwrapping convention or retained cycle memory as well as an independently calibrated angular frequency.

Why this is not the split-complex unit

A split-complex unit j instead satisfies j²=+1. Its real action exchanges the coordinates: S(x,y)=(y,x). The exponential is coshη I+sinhη S and preserves x²−y², rather than the positive norm used here.

DTT can investigate ordinary phase for coherent generation and a hyperbolic pairing for temporal or spacetime readout. Their different multiplication rules must remain explicit. The plotted circle is an ordinary phase construction. It is not a boost diagram and cannot establish a Lorentzian metric merely by renaming J as a temporal symbol.

Phase is one part of the reconstruction

An oriented real generator A=ωJ with ω>0 selects the displayed quarter-turn after its positive rate magnitude is factored out. Reversing the generator selects −J. This is a useful finite example of phase supported by dynamics, developed in the linked guide.

Quantum probabilities, subsystem composition, completion instruments, and the action scale require additional structure. In SMM/DTT the next task is to derive compatible versions from one source law. The six nested inner roles concern that generation; they are not six independent angles in this widget. Reset restores forty-five degrees, and the static circle supplies the same worked example without scripting.

Scope of this guideExact real-plane rotation and operator identities. The demonstration does not derive a probability rule, action scale, physical clock, or Lorentzian spacetime.

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