Why 44,100? The Accidental Physics of the CD Sampling Rate

The CD sampling rate grew out of 1970s video-based PCM recorders. PAL-compatible equipment used 44.1 kHz; colour NTSC equipment used the nearby 44.056 kHz. Sony and Philips then chose one rate for the disc: 44.1 kHz.

5 August 2024 · 11 min · Sebastian Spicker

How Cats Drink: Inertia, Gravity, and the Froude Number at the Tip of a Tongue

Cats use the dorsal surface of the tongue tip to entrain a liquid column, then close the jaw before gravity and pinch-off remove it. Reis and colleagues modelled the timing with inertia, gravity, a Froude number, and the tongue’s travel geometry. The relevant domestic-cat parameter is a modified Froude number near 0.4—not the simple Froude number near one.

22 July 2024 · 5 min · Sebastian Spicker

Are Cats Liquid? The Deborah Number and the Rheology of Cats

Marc-Antoine Fardin won the 2017 Ig Nobel Prize for a playful application of rheological language to cats. The Deborah number De = τ/T is a standard timescale ratio for materials; assigning a cat a relaxation time is an analogy, not a rigorous material classification.

3 April 2024 · 6 min · Sebastian Spicker

When Musicians Lock In: Coupled Oscillators and the Physics of Ensemble Synchronisation

The Kuramoto model explains how heterogeneous phase oscillators can develop collective synchrony. It is a useful analogy for ensemble timing, applause, and delayed feedback, but it does not by itself predict a universal networked- music latency limit or prove neural coupling between musicians.

8 February 2024 · 7 min · Sebastian Spicker

LK-99: Six Weeks That Showed How Physics Works

On July 22, 2023, a Korean preprint claimed that LK-99 — a copper-doped lead apatite — was a room-temperature, ambient-pressure superconductor. Within six weeks, converging null results and impurity studies had rejected the claim. The episode is more interesting for what it revealed about the sociology of science than for the compound itself: how a global community self-corrected at extraordinary speed, and how the media managed to fail at conveying uncertainty despite watching it happen in real time.

9 October 2023 · 15 min · Sebastian Spicker

Zero Angular Momentum: The Falling Cat and the Geometry of Shape Space

A cat dropped upside-down rotates 180° and lands on its feet, despite having zero angular momentum throughout. This is not a trick and not a violation of physics. The explanation took physicists from 1894 to 1993 to fully work out, and the answer — a geometric phase arising from the holonomy of a fiber bundle — is the same mathematics that governs the Berry phase in quantum mechanics and the Aharonov-Bohm effect in electrodynamics. We adopted two strays this year. They fall beautifully.

3 October 2023 · 10 min · Sebastian Spicker