We present a numerical characterization of spatiotemporal chaos in a one-dimensional system of complex Ginzburg-Landau fields coupled through a non-reciprocal chiral interaction. Using a spectral exponential time-differencing integrator (ETDRK4) together with a Benettin Lyapunov analysis we establish three results. First, non-reciprocity is necessary for chaos in this system: reciprocal coupling keeps the fields fully phase-locked and non-chaotic at every coupling strength examined, while non-reciprocal coupling breaks synchronization above a threshold and produces chaos within a finite coupling window. Second, the chaotic state is extensive hyperchaos: the full Lyapunov spectrum contains several positive exponents together with a single near-zero (neutral) exponent and a negative tail, and the Kaplan-Yorke dimension is large and grows with system size. Third, the strength of the chaos depends non-monotonically on the number of coupled fields, with a maximum at three. We position these findings explicitly within the recent literature on non-reciprocal phase transitions and chaos. The underlying mechanism is established physics. The contribution of this note is a clean and reproducible characterization, not a new mechanism, together with the observation of the field-number dependence.
Oren Speiser (Wed,) studied this question.