Sorry for your deferral. I would disregard the above comment about conceit if I were you. However, I do think it is best for you to move on at this point. There is very little you can do to rectify the situation. The AO in charge of your app gave you an opportunity to demonstrate your aptitude/brilliance in physics and was willing to put it before the physics dept. for review. Solutions to two first year college level problems unfortunately didn’t show much, if anything, to them. I disagree with the poster on your other thread about the inability of kids to do original work as I was someone who did. I think this is what they were looking for or at least some evidence that you are capable of doing so if you were accepted to arguably one of the top physics depts in the world.
Focus on your other apps and don’t spend any more time thinking about this. I’m sure you have a lot to offer whatever school is lucky enough to have you. Harvard has moved on to the 34,000 apps ahead of them. They are not looking backwards at this point and offering you another chance I’m sorry to say.
Best of luck with everything!