Identity management/MIM - application authentication - clarification?

With identity management, something like Microsoft Identity Manager, does this mean that if you have an application on-premise, and you have A.) an Active Directory, and B.) an ADLDS also on-premise, that the application can authenticate a user from both A and B by connecting to an identity management server via LDAP instead?   
Is there a meta-verse where their login is created and password is sync'd from ADLDS or AD, and it the application authenticates against the meta-verse/MIM database?