An all-optical general-purpose CPU and optical computer architecture

Status of the Paper and arXiv Use

• Many comments question a private company putting what feels like a press release into an arXiv-style LaTeX paper, without peer review.
• Concerns that arXiv is being “polluted” by PR-like manuscripts, making it harder for non-experts and some investors to distinguish solid science from hype.
• Counterpoint: technically rich “PR papers” at least expose enough detail for real experts to spot nonsense, unlike traditional marketing blurbs.
• Several posts argue that formal peer review itself has serious credibility problems (citation extortion, gatekeeping), so its absence is not a reliable negative signal.

Fundamental Limits of Optical Computing

• Strong claim: general-purpose, large-scale integration is impossible (or extremely unlikely) because optical feature sizes are limited by wavelength (~1.5 µm), orders of magnitude larger than modern electronic transistors.
• This implies optical CPUs of equivalent complexity would be enormous.
• Others note potential mitigations: wavelength-division multiplexing (many channels per waveguide), vertical stacking, plasmonics, metamaterials, and near-field/superlens techniques.
• Disagreement over whether higher clock rates, lower heat, and richer interconnect can realistically offset low device density.

Switching, Nonlinearity, and Efficiency

• Some readers look for a clear explanation of the “optical transistor” / switching mechanism; one points to semiconductor optical amplifiers and cross-gain/phase modulation as the canonical approach.
• Another line of critique cites prior work arguing optical transistors are fundamentally inefficient: photons interact weakly and require strong nonlinearities (high intensities), so energy advantages may be overstated.
• Use of 2D materials is viewed skeptically as a hand-wavy fix with limited interaction volume.

Architecture, Memory, and SUBLEQ Demo

• The paper’s architecture is framed as relevant only after optical interconnects are already mainstream; current work is a conceptual “next phase” focused on energy efficiency.
• Actual hardware demo is a 2‑bit SUBLEQ one-instruction machine using optical components; critics note it cannot realistically “run Doom” and relies on slow delay-line memory and ROM-like or phase-change-style storage.
• Some appreciate the architectural exploration and especially a figure plotting compute vs power vs global energy limits, calling it a useful big-picture framing.

Overall Sentiment

• Mix of enthusiasm for the conceptual work and diagrams, and strong skepticism about practicality, scalability, and the risk of overhyping optical general-purpose CPUs.