Interactive App: GW Explorer

GW Explorer is a fully client-side gravitational-wave exhibit: a guided portal, a CBC waveform explorer, a DSP filter-design explorer, and four matched-filter search games. It ports real IMRPhenomD and IMRPhenomPv2 waveforms to pure TypeScript, so LIGO-grade physics runs entirely in the browser with no server.

Launch Live App View Source

From Camp Handouts to a Browser Exhibit

For the 2024 PSU Science-U Gravitational Waves Camp I wrote a set of Python apps to teach students how a compact binary coalescence (CBC) search works, alongside a standalone Dash tool for digital filter design. They did the job, but each needed a Python server, and the physics leaned on LALSuite and SciPy running behind the scenes.

GW Explorer is the browser-native successor: a single-page app that consolidates those tools into one guided exhibit and moves all of the physics into the browser itself.

Figure 1: The GW Explorer portal, a guided entry point to the exhibit.

What’s Inside

• CBC Waveform Explorer: Dial in component masses and spins and watch the time-domain strain, the frequency-domain amplitude, and the spectrogram update live, using real IMRPhenomD and precessing IMRPhenomPv2 waveforms.
• DSP Filter Explorer: Drag poles and zeros and see the Bode and impulse responses respond in real time, the successor to my earlier Dash filter app.
• Search games: Four ways to play a parameter-estimation search (visual, audio, spectrogram, and matched-filter SNR), tuning masses and spins until your template matches a hidden event.

Figure 2: The CBC Waveform Explorer: masses and spins on the left, with the time domain, frequency domain, and spectrogram updating live.

Figure 3: The spectrogram search game: match your template’s chirp track to the one hidden in the detector data, then lock your guess.

Putting LALSuite in the Browser

The interesting engineering was removing the server. The original apps generate waveforms with LALSuite’s lalsimulation. Because IMRPhenomD is an analytic, closed-form frequency-domain model rather than a numerical simulation, I could port its actual equations and calibrated coefficients (and the IMRPhenomPv2 precession layer) directly to TypeScript, the same way the old app ported SciPy’s filter routines.

The result is a genuine waveform approximant running entirely client-side. It is validated against reference waveforms dumped from LALSuite: the PhenomD strain matches to better than one part in \(10^5\), and the precessing PhenomPv2 polarizations agree to comparable precision across single- and double-spin systems. There is no server, no LALSuite, and no SciPy in the deployed app.

Tech Stack

GW Explorer is built with Vite and TypeScript, React 19 and Tailwind CSS, a hash router for clean GitLab Pages hosting, Zustand for state, and Plotly.js for the graphics. The build is fully static, and the whole exhibit, physics included, runs from a single set of files with nothing behind it.