Could anybody kindly explain the main difference please? From what I've read on university websites, they're pretty much the same within a uni, with the exception of one or two minor modules being different.
Well I assume in straight physics you have to take lab modules which take up a significant amount of time. And I suppose in theoretical physics you would have to take a lot of extra maths modules to be able to understand the harder stuff. I think physics will have more of a practical element to it, and theoretical physics more of a mathematical element basically.
Not being a physics student, but having a friend who does straight physics and boyfriend doing theoretical- seems that instead of doing the lab sessions, the theoretical people do maths-y stuff. From what I can tell, that makes up about six hours a week...
It depends on the uni. At Durham there is no difference between theoretical physics and physics until the 3rd year, where the physicists carry on labs and us theoretical physicists do no labs and theoretical modules (essentially more maths from what I understand).
From what I can remember from applying last year similar things are true of most unis. Often it's the case that an optional module in the first year for normal physicists isn't optional for the theoretical physicists and they do extra maths or something along those lines. You'll have to check how each uni works individually I'm afraid.
Really it shouldn't matter what you go for now, you don't really know which way you want to head yet. Every uni I looked at allowed for very easy transfers between their courses in the first or second years.