Constants & Units · constant
Planck time
t_P = 5.391 247(60) × 10⁻⁴⁴ s
- Unit
- s
- Value
- 5.391 247(60) × 10⁻⁴⁴
- Exact
- no
- Note
- Light crossing a Planck length. No theory describes the universe before one of these.
- Symbol
- t_P
- Category
- Universal
- Numeric
- 5.391247e-44
- Uncertainty
- ±1.1 × 10⁻⁵ relative
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