4 Experiment 3: Scaling

Python: scaling_1.py, scaling_2.py

We scale to longer chains (L = 4,6,8,12,16) and more frames, testing whether momentum quantisation k = 2πm∕L holds and whether the boson properties depend on system size.

The key result — analytically exact

For any single fermion hop from site 0 to site d, regardless of L or d:

     1
ψ = √--(e0 + ied).
      2

The boson matrix has exactly two non-zero entries:

         i             i
B0,d = + 2,    Bd,0 = − 2.

For the nearest-neighbour hop (d = 1, L = 4) this reads explicitly:

     (        i      )
        0   + 2  0  0
     || − i   0   0  0||
B  = ||   2           || .
     (  0    0   0  0)
        0    0   0  0

The same 2×2 antisymmetric block (

0 +i∕2
i∕20

                        ) is embedded at positions (0,d) and (d,0) for any hop distance d and any chain length L; all other entries are zero. The matrix is always purely antisymmetric, always has eigenvalues ±12, and the phase of B0,d is always π∕2, giving:

k ⋅d = − π  = ⇒   k = − -π-.
        2               2d

This is not a plane-wave momentum but a phase relationship between the two fermion sites: the boson encodes exactly one number, the π∕2 phase shift between where the fermion was and where it went. A quarter-turn in phase space is the defining property of a propagator. This is what a virtual photon does in QED.

Conclusion: The compression residual of a single fermion hop is an antisymmetric, purely imaginary, ±12-eigenvalued object carrying a universal π∕2 phase, independent of chain length and hop distance.