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Orders of magnitude: Distance A long length scale diagram.
Baez's Length scales in physics
Conversions
| unit | | | |
| megaparsec Mpc | 1022 × 3.086 | | |
| parsec pc | 1016 × 3.086 | | |
| light-year ly | 1016 × 0.9461 | | |
| astro. unit AU | 1011 × 1.496 | | |
| light-second ls | 108 × 2.998 | | |
| mile mi | 103 × 1.852 | nautical | |
| mile mi | 103 × 1.609 | land | |
| kilometer km | 103 × 1.000 | | |
| yard yd | 100 × 0.9144 | | |
| foot ft | 10-1 × 3.048 | | |
| hand | 10-1 × 1.016 | | |
| inch in | 10-2 × 2.540 | | |
| mil | 10-5 × 2.540 | | |
| micron | 10-6 × 1.000 | um | |
| angstrom A | 10-10 × 1.000 | | |
| 10 × | | |
| 10 × | | |
Notes
Currently in pre-first-draft state...
wavelength of a 1 eV photon (hc/eV) 1.240 × 106
From [Cow, p235]:
atmosphere: 1/2 pressure 5600 m, top of troposphere 12000 m
mean oceanic depth 3730 m, of oceanic mixed surface layer 75 m
mean elevation of continents 840 m
average Earth-Sun 1.495 × 1011
earth radius 6.4 × 106
radius universe 10^26, sun 6.96e08, moon 1.74e06
mean Earth-Moon 3.84e08
galactic disk is ~30 kpc, so 0.93 × 1021 m
Baez's Length
scales in physics
(I don't really understand this yet, but its something like:
- Bohr radius - size of a one-electron fuzzball (ie hydrogen. About 10-11 m.),
- Compton wavelength of electron - length at which non-quantum classical
thinking is completely broken. (100 smaller
than hydrogen. About 10-13 m.)
- Classical electron radius - length at which you have to pay attention
to the tiny mass that electric fields have.
(100 times smaller than Compton. About 10-15 m.)
- Planck length - nice familiar 3 dimensional space gets really wierd at
this scale. Sortof like looking really closely at
your skin... flat until you look closely enough to see
the pores and tiny rinkles and stuff. (Tiny, 10-35 m.)
Length
Area
Volume