# Hubble length

1. Jul 17, 2008

### Golfer

I am presently reading a paper on Inflation. It uses the term Hubble length. Can someone provide the Hubble length in cm.

2. Jul 17, 2008

### marcus

The Hubble time is about 14 billion years. That means the Hubble length is about 14 billion lightyears. 13.8 might be better.

definitions: the hub time is 1/H0
the hub length is c/H0

just use google calculator. type this into the google search window verbatim
71 km/s/megaparsec
and press "search"

you will get an inverse time in Hertz

now type c divided by that, verbatim, in other words
c/(71 km/s/megaparsec)
and say search again

you will get 1.3 x 1026 meters

that is the hubble length in meters
google calculator will just calculate it for you automatically and tell you that

Last edited: Jul 17, 2008
3. Jul 17, 2008

### Mk

Thus, it is probably silly to describe it in centimeters.

4. Jul 17, 2008

### Coin

Google calculator also does automatic unit conversion, you can say things like

c/(71 km/s/megaparsec) in centimeters

It is a great tool.