What do you really need to authenticate?

To login to your account you need a username and password and maybe an MFA token if they feel like being secure. But can you use other pieces of information to change or bypass the need for a password or token? Could you, by going through a whole bunch of processes and what not, login with an email address or a drivers license? In this presentation I will go over authentication trees, mapping them out, and figuring out what can really be used to authenticate.