Is there a way to use multiple instances yet a single login? (BuddyPress)

Hello WordPress community,

My question is a bit complicated. Currently, I am interested in using WordPress to make a new website which allows users to submit their own content which is to be featured on the main pages. The idea will use BuddyPress, as that is the best social networking plug-in for WordPress. The idea, however, is to have multiple sections, each focused on a different topic. What I mean is that the main page will have links to each sub-topic, and each sub-topic will be a subdomain with it’s own complete site. For example, on http://www.website.com/, you will click on a link that leads you to the art portion of the site, which directs you to http://art.website.com/, and is it’s own instance of BuddyPress since it has it’s own unique pages, etc. However, I want to have one login for every one of these instances, so no matter which subdomain you go to, you still only have one profile and one registration that you are logged in through.

Is there a way to accomplish this using WordPress, or am I better off looking out to code my own log in and create my own site from scratch? Thank you for your responses.

Best,
Weasel