#### marcus

Science Advisor

Gold Member

Dearly Missed

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Units based on c=G=hbar=k=e=1 turn out to be quick and convenient to use, and one can get used to the scales (a point damgo made earlier in the dimensionless units thread).

Heres a kind of minimal toolkit for working with them including some handy comparisons with familiar units.

E38 ----a mile

E44-----a million miles

E60-----1.7 billion years

E6 ------22 grams

the proton compton wavelength----2.103E-14 meter---13E18

the CMB temperature-----2.725 kelvin----------1.93E-32

the Hubble time----4.35E17 seconds------------8.06E60

average sunlight photon----2E-19 joules----------E-28

the distance to the sun----150 million km---------93E44

earth orbit speed------30 kilometer/second--------E-4

solar constant----1380 watts/sq.meter------------E-119

2.701k----3.73E-23 joule/kelvin-------------------2.701

sigma-----5.67E-8 watt/sq.meter kelvin

a (the aT

I'll show some examples of the kind of things I want to do with

this toolkit.

Heres a kind of minimal toolkit for working with them including some handy comparisons with familiar units.

E38 ----a mile

E44-----a million miles

E60-----1.7 billion years

E6 ------22 grams

the proton compton wavelength----2.103E-14 meter---13E18

the CMB temperature-----2.725 kelvin----------1.93E-32

the Hubble time----4.35E17 seconds------------8.06E60

average sunlight photon----2E-19 joules----------E-28

the distance to the sun----150 million km---------93E44

earth orbit speed------30 kilometer/second--------E-4

solar constant----1380 watts/sq.meter------------E-119

2.701k----3.73E-23 joule/kelvin-------------------2.701

sigma-----5.67E-8 watt/sq.meter kelvin

^{4}--------pi^{2}/60a (the aT

^{4}law)---7.565E-16 joule/cub. meter kelvin^{4}---pi^{2}/15I'll show some examples of the kind of things I want to do with

this toolkit.

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