UBC Physics does not generally accept students to PhD programs unless they already hold a Canadian MSc or equivalent (something requiring both coursework and a thesis usually). Some other info that may help others thinking about UBC (and maybe other Canadian schools):
1. It may be possible for you to get promoted from MSc program to a PhD program after year 1, if you show excellent grades, that you are capable for PhD research, and if you have your supervisor's support.
2. All Physics & Astronomy students must take PHYS 500, the quantum field theory course.
3. Canadian schools stipends do NOT generally include a tuition waiver, except for an extra award to cover the difference between domestic and international tuition. Domestic tuition is $4500 per 12 month period.
4. When you finish your MSc at UBC (if they did accept you for that instead of PhD), you will have to reapply to PhD programs again. However since you are basically accepted if the prof is willing to fund you, this is most likely a formality (unless there are funding issues). Canadian schools do not usually assume their students will automatically do a PhD in the same place, make sure your prof will have funding for you if you want to do PhD there too.
5. Teaching assistants are mostly unionized in Canada. Here is the UBC TA Union website:
http://cupe2278.ca/blog/ I am mentioning this because the collective bargaining agreement is expiring and there are some job action issues coming up potentially. The website will give you up to date info! Having been at UBC and other Canadian schools, I can say that TAs at UBC make about 1/3 of the wage (~$27/hr instead of ~$37/hr) and work 1/3 more hours (1 unit is 12 hrs/week instead of 9hrs/week) than TAs at comparable Canadian schools (e.g. Toronto). This means you will still get the same of money in the end as your peers in other schools, but you have to work much more!