# Math Is Fun Forum

Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫  π  -¹ ² ³ °

You are not logged in.

## #1 2022-12-13 07:39:34

Keckman
Member
From: Helsinki Finland
Registered: 2022-12-13
Posts: 14
Website

### How small is Planck's time?

Let's try to figure out...

``````rebol[]
rH: 2 * 53e-12; the diameter of a hydrogen atom m
UNIage: 13.82 * 1000000000 * 365.25 * 24 * 60 * 60; the age of the universe in seconds
PlaTime: 5.39124760E-44; Planck time in seconds
c: 299792458; Speed of light m/s
age2: 60 * 60 * 24 * 365.25 * UNIage * PlaTime
dist: age2 * c
print rejoin["If the length of a year shrunk to a Planck time, the age of the universe would be " age2 " seconds, in which time light travels " dist " meters, whcich is " round/to (dist / rH) 0.0001 " times diameter of a hydrogen atom."]
halt``````

output:
If the length of a year shrunk to a Planck time, the age of the universe would be 7.42002306076851E-19 seconds, in which time light travels 2.2244669518044
7E-10 meters, whcich is 2.0986 times diameter of a hydrogen atom. Huh! Small?!

Offline