Combine two ActiveRecord::Relation objects

Suppose I have the following two objects: first_name_relation = User.where(:first_name => 'Tobias') # ActiveRecord::Relation last_name_relation = User.where(:last_name => 'Fünke') # ActiveRecord::Relation is it possible to combine the two relations to produce one ActiveRecord::Relation object containing both conditions? Note: I'm aware that I can chain the wheres to get this behavior, what I'm rea