*Comparison of three current-phase relations: standard Josephson (linear), parity-symmetric boundary (quadratic), and Hubble-biased boundary (quadratic + induced linear)*
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<canvas id="cpr" role="img" aria-label="Line chart comparing three current-phase relations across phase difference from -1 to 1">Three curves: standard Josephson (linear), parity-symmetric (quadratic), and Hubble-biased (quadratic plus linear).</canvas>
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<span style="display:flex;align-items:center;gap:4px;"><span style="width:24px;height:3px;background:#185FA5;border-radius:1px;"></span> Standard Josephson: J ≈ J_c δφ</span>
<span style="display:flex;align-items:center;gap:4px;"><span style="width:24px;height:3px;background:#D85A30;border-radius:1px;"></span> Parity-symmetric boundary: J ∝ δφ² sgn(δφ)</span>
<span style="display:flex;align-items:center;gap:4px;"><span style="width:24px;height:3px;background:#0F6E56;border-radius:1px;display:inline-block;border-top:2px dashed #0F6E56;height:0;"></span> Hubble-biased: quadratic + induced linear</span>
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<div style="font-size:12px;color:var(--color-text-secondary);margin-top:12px;line-height:1.6;">
The parity-symmetric curve (coral) is flat at the origin — no linear response. The Hubble bias (dashed teal) restores a linear term at small δφ, recovering Newtonian gravity, while the quadratic term dominates at large δφ (MOND regime).
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