Convert Shakes to Planck Time

Convert Shakes (sh) to Planck Time (t_P) instantly and accurately.

Shakes (sh)
Planck Time (t_P)

Conversion Formula

t_P = sh × 1.854858440e+35

About Shakes

A shake = exactly 10 ns (10⁻⁸ s) - the informal unit for fission prompt-neutron generation time, coined at Los Alamos during the Manhattan Project (1943-1945). A prompt-neutron generation in a supercritical core takes ~1-10 shakes; a full explosive chain reaction unfolds over ~50-100 shakes. The name alludes to 'two shakes of a lamb's tail'. Still used in reactor physics and weapons-design calculations. 1 shake = 10 ns.

About Planck Time

The Planck time (t_P) = √(ℏG/c⁵) ≈ 5.391 × 10⁻⁴⁴ s — the time for light to travel one Planck length (~1.616 × 10⁻³⁵ m). Below this scale, general relativity and quantum mechanics both break down; a theory of quantum gravity is needed. No physical process or instrument approaches this timescale — it is a theoretical lower bound. Introduced by Max Planck in 1899. 1 t_P ≈ 5.391 × 10⁻⁴⁴ s.

Quick Reference Table

Shakes (sh)Planck Time (t_P)
1 sh1.855 × 1035 t_P
2 sh3.71 × 1035 t_P
5 sh9.274 × 1035 t_P
10 sh1.855 × 1036 t_P
25 sh4.637 × 1036 t_P
50 sh9.274 × 1036 t_P
100 sh1.855 × 1037 t_P

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