Is there anyone out there that knows how to define the p operator for a 2-d box. Please can you give a full answer, and not only a hint. I think that no one on this planet knows what it is. I have looked all over the internet. If there is no answer. Why don't people just say it? I think nobody knows. There is absolutely no information on the square of the magnitude of the momentum for a 2-D particle in box. Is this a unexplored portion of quantum physics? Am I embarking on a new concept that Schrodinger never considered? It seems so. Please feel free to respond to my discovery. An answer would be nice. Thank you.