Through the Facebook UI a user can create a so called "Life Event" on his timeline (which is actually an Open Graph activity) and add specific attributes to this activity, for example:
Started a new Job; attributes: employer, position, location, time, story
The Facebook Build-in Action Types and the Build-in Object Types do not include anything that would result in an Activity like the one above. So my question is: Is it posible to create such "Life Events" with the Open Graph API, which would look similar to those created through the Facebook UI, without defining my own action and object types?
It is not possible to create Life Events for users. Though it is possible for pages:
https://developers.facebook.com/docs/graph-api/reference/life-event