Hard to tell how they happened, but swirl marks are nothing more than minor scratches in a circular pattern.
Possible causes:
- abrasive cleaning item (mitt, towel, etc)
- abrasive drying cloth/material
- overly enthusiastic use of a buffer, or bad use of a buffer. Or bad product choice.
- abrasive cleaner or wax application/removal
You say your car is brand new, it should be fairly easy remove minor swirls. I'd try a paint cleanser or cleaner wax on a spot to see if that fixed it, and if not, read the threads and articles here to move gradually to more aggressive products.
I highly recommend removing them now, then protecting that nice new paint with something durable - Klasse or Zaino come to mind. You might also find that the first steps in the Klasse or Zaino treatment will fix the swirls for you anyway....
blue skies, and welcome to the forum!
andy