Gravitational Wave Information Encoding A First Characterization of LIGO Strain Data as a Shannon Information Channel

Classical treatments of gravitational wave (GW) physics focus entirely on source characterization and waveform detection. We introduce a complementary perspective: gravitational waves as an information channel in the sense of Shannon's information theory. We make five contributions. (i) We derive a formal channel capacity bound for GW perturbations, treating strain amplitude, frequency, polarization, phase, and arrival time as independent degrees of freedom (DOF) across the LIGO science band (10-2000 Hz). (ii) We propose a multi-DOF bit-encoding scheme mapping information bits onto waveform parameters-including amplitude keying, frequency shift keying, polarization keying, and phase shift keying-and construct a polarization constellation analogous to QAM modulation. (iii) We develop a quantum-noise-limited noise model characterizing fundamental retrieval limits imposed by shot noise, radiation pressure noise, seismic noise, and the Standard Quantum Limit (SQL) as a function of frequency. (iv) We derive theoretical Bit Error Rate (BER) curves for each encoding scheme and validate them against Monte Carlo simulations (n=10,000 trials per SNR point). (v) We apply the framework to a GW150914-class synthetic event and report a total channel capacity of 82.6 kbits/s across five DOF at SNR = 25 dB, with polarization keying achieving BER < 10s³ at SNR > 12 dB. This is the first formal characterization of gravitational wave perturbations as a Shannon information channel.