SPECTRAL v2.2.0 Audible Geometry and Photon-Sphere Sonification

SPECTRAL v2.2.0 brings two new zero-install browser applications into one repository release: SPECTRAL E8 Geometry Studio 1.0 and SPECTRAL Photon-Sphere Sonification Laboratory 1.0.

Both applications run locally by opening index.html. They require no server, Python runtime, Node runtime, npm package, build step, CDN, account, telemetry, or network connection.

Release highlights

SPECTRAL E8 Geometry Studio 1.0

E8/APP/ is a less restrictive, composition-first instrument for experimenting with musical geometry across the complete 240-root E8 system and an evolving eight-dimensional Cartan torus.

Highlights include:

• three hard-separated render domains: Canonical Deterministic, Replay-Safe, and Creative Non-Deterministic;
• five trajectories: Cartan Sweep, Coxeter Orbit, Triality Spiral, Qutrit 4D Orbit, and Root Walk;
• deep and centred φ ladders, harmonic and minor fields, and E8-height pitch mapping;
• eight factory geometries, an eight-axis Cartan mixer, root-density controls, scene A/B capture and morphing, and audio A/B comparison;
• torus, orbit, triality, trinaural, qutrit-4D, and near-mono spatial maps;
• fast 8-second previews and full stereo PCM16 renders up to 120 seconds at 44.1 or 48 kHz;
• waveform, spectrogram, projected 240-root map, and bounded eight-coordinate trajectory views;
• WAV, recipe, fingerprint, manifest, observation contract, trajectory, upload-readiness, and deterministic ZIP-bundle exports.

Canonical mode uses a versioned integer E8/DSP contract for intended cross-runtime byte identity. Replay-Safe binds its Float64 render to the recorded runtime. Creative mode draws fresh local entropy for every take and intentionally refuses exact manifest replay; the WAV hash is the authoritative identity of that performance.

SPECTRAL Photon-Sphere Sonification Laboratory 1.0

SMBH/ is a deterministic auditory model of photon-sphere and whispering-gallery mode families in the curved optical black-hole analogue reported by Xu et al., with a clearly segregated Kerr 220 sonification extension.

Highlights include:

• paper-grounded optical-path relationships for the photon-sphere, edge-WGM, and outer-WGM families;
• inverse-optical-path frequency mapping, editable auditory anchor, partial stacks, and pedagogical Q controls;
• pure ringdowns, mode-family combs, a constructed pump-configuration montage, an analogue laboratory narrative, and a virtual pump-position scan;
• a separate Kerr 220 engine for exploring an audible spin-dependent analytic fit without attributing it to the Schwarzschild microcavity experiment;
• Canonical Strict integer rendering and Replay Safe Float64 rendering;
• local waveform and spectrogram inspection;
• PCM16 WAV, manifest, normalized recipe, fingerprint, and human-readable mode-table exports;
• fail-closed deterministic manifest replay and browser-native known-answer tests.

The laboratory is an auditory interpretation. It does not recreate the microcavity fabrication process, solve the complete Maxwell/eigenmode problem, simulate laser gain or a black-hole merger, or produce a gravitational-wave detector signal.

Shared offline architecture

The two new applications continue SPECTRAL's lean browser workflow:

• direct file:// operation with no installation or localhost service;
• local-only synthesis, analysis, playback, hashing, and export;
• explicit PCM16 quantization and RIFF/WAV writing;
• canonical recipes, SHA-256 identities, manifests, and mode-scoped replay contracts;
• Canvas-based waveform and spectrogram views that do not affect render identity;
• restrictive Content Security Policies and no production network client;
• self-contained browser test pages beside each application.

Documentation update

The repository README now lists both new applications in Project areas and exposes all four browser-native SPECTRAL applications in Quick start:

APP/index.html                 Deterministic Sonification Workbench 2.0
E8/APP/index.html              E8 Geometry Studio 1.0
SMBH/index.html                Photon-Sphere Sonification Laboratory 1.0
PHOTOACOUSTIC/index.html       Photoacoustic Laboratory 2.0

Getting started

git clone https://github.com/QSOLKCB/SPECTRAL.git
cd SPECTRAL

Then open either new instrument directly:

E8/APP/index.html
SMBH/index.html

Their browser-native test suites are available at:

E8/APP/tests/index.html
SMBH/tests/index.html

No migration is required for the existing Python experiments or APP/ Workbench. The new applications are additive. Provenance manifests remain bound to the application, engine, mode, and version that created them.

Important reproducibility notes

• E8 Canonical Deterministic and SMBH Canonical Strict are the archival render paths.
• Replay-Safe artifacts promise exact replay only when the recorded browser/runtime fingerprint matches.
• E8 Creative Non-Deterministic recipes can restore settings for a new take but cannot reconstruct the previous entropy or audio.
• Keep the WAV, recipe, fingerprint, manifest, and contract artifacts together when archiving a render.

Source and citation boundaries

The SMBH optical-analogue mapping is grounded in:

Xu et al. (2026). Photon-Sphere Modes in Curved Optical Microcavities: A Black-Hole Analogue Laser. Advanced Science, 13, e17466. https://doi.org/10.1002/advs.202517466

The E8 Studio is an explicit sonification and composition mapping built from the repository's E8, triality, φ-fractal, qutrit, and provenance-oriented experiments. It does not claim that a rendered WAV is a physical E8 measurement, cosmological observation, or quantum-computing result.

For the wider research context, see the SPECTRAL repository README and the cited Zenodo records for Spectral Algebraics and Collective Modes.

License and credit

Released under the repository's MIT License.

Created by Trent Slade / QSOL-IMC.