What would the major be called if say I wanted to go into building an anti-matter device or designing space vehicles or inventing artificial gravity devices? Thanks.

Sounds like you want to go into Physics, more specifically particle physics (for the anti matter and/or gravity) but maybe something more like aerospace or aeronautical engineering for the space vehicle.

Is it possible to do both?

Possible, yes. Practical? Depends on how much time you have.

Possible, yes. Practical? Depends on how much time you have.

 

Yea. I don't know. I see the SciFi shows and theres a theoretical astrophysicist and an engineern all in one.

I wonder if most people, that wish to work in such a field, decide to work for NASA instead of a corporation.