[lucagalbu]

Hi! I had to send a message to a physics forum, but I'd like to know if it's syntactically and grammatically correct. Can you please check it out?

"Hi! I was taught that the dirac matrices are AT LEAST 4x4 matrices, so that means that I can find also matrices of higher dimensions. The question is: what do these higher-dimension-matrices represent? Are they just mathematical stuff or have they got a physical meaning? I ask that because in every textbook and in every course I used only the 4x4 matrices...
Thanks"

And just another thing: I used to start topics saying: "Hi there!": is this right or it sounds wrong/odd?

Thank you!