Background: I am an international student doing Mathematical tripos at Cambridge and I have just completed my first year with a 2.i. I did 'Maths with Physics' for my first year. The following paragraph is taken from the department's course website. "The Mathematics with Physics option consists of courses given by the Faculty of Mathematics, which provide about three-quarters of the total workload, and courses given by the Physics department, including practical work, which provide the remaining quarter of the workload. The physics lectures cover Mechanics and Molecules (Newton’s Laws, states of matter, kinetic theory, properties of gases, liquids and solids), Oscillations and waves (including electric circuits and fourier analysis), Fields, Relativity and Quantum Physics (including electromagnetism, special relativity, quantum mechanics and cosmology). The mathematical lectures are on Vectors and Matrices, Groups, Differential Equations, Vec- tor Calculus, Analysis and Probability." For my second year I have the option to either continue doing maths or to transfer to the Cavendish for physics (as part of the NatSci course). There is a link to the course page. I have always loved doing physics and applied maths but lately I've enjoyed the pure maths courses very much. I enjoyed my first year there at Cambridge and learned a lot but currently I'm undecided as to what option I should pursue. My questions: Would not getting a 1st reflect poorly on me when applying to the top US physics departments? I am interested in the theoretical areas of nanotechnology but I would also consider other areas of theoretical physics. I am not decided as I still would like to explore more. So considering my interests, should I do maths or physics? If I do continue doing maths, will not doing experimental physics be a disadvantage in pursuing theoretical physics later on? WIll not doing experimental physics be a huge disadvantage when I later pursue a career in nanotechnology? My guess is that it will because the field is very applied and you need experimental skills to succeed in it. What can I do to further improve my undergraduate experience in studying maths and physics? I mean in terms of the kinds of internships and research activities and where to consider doing them. Thanks a lot for reading this and answering my questions. I would really appreciate some guidance.