rvmを使ってインストールしようとするが、、

rvm install 2.0.0

さっそくエラーが出た。

エラー

There is no checksum for 'http://production.cf.rubygems.org/rubygems/rubygems-2.0.3.tgz' or 'rubygems-2.0.3.tgz', it's not possible to validate it.
This could be because your RVM install's list of versions is out of date. You may want to
update your list of rubies by running 'rvm get stable' and try again.
If that does not resolve the issue and you wish to continue with unverified download
add '--verify-downloads 1' after the command.

There has been an error while trying to fetch rubygems. 
Halting the installation.

下記コマンドで無事インストール完了。

rvm uninstall 2.0.0
rvm get stable
rvm install 2.0.0 --verify-downloads 1