Orals Questions: Algebraic Number Theory - For which integers n is 3500 a square mod n? - Does the method you used to determine this work in general? - Is this effectively (polynomial-time) computable with the method you used? (In my case, Legendre symbol.) What about in general? (Think Jacobi symbol.) - Regarding the field extension K := Q(i) of Q: - Give the conductor. - Describe the splitting/ramification of primes (including infinite). - Relate the Galois group to a ray class group via Artin map. - Factor \zeta_K as a product of \zeta_Q and another function (directly from definition of \zeta). - Identify this other function; relate it to the above; where does it converge as a Dirichlet series? * Also related this to: how do we count the number of ideals in a ring of integers with norm bounded by n? Algebraic Topology - Compute cohomology group and ring structure on CP^n. - Is there an orientation-reversing diffeomorphism on CP^2?