Hi guys, I am currently at a crossroads where I have to make an important decision and was hoping the kind members of the PF forums could help me. I have a Master's degree in Mechanical Engineering from an Ivy League school (GPA - 3.88). Lately, I have had the opportunity to rekindle my interest in pure physics and applied math. Initially, I intended to study these topics as a 'general interest' thing. However, I think I might want to gain an in-depth mathematical foundation of physical phenomena and work at a research level on select topics - I'm gravitating towards particle physics & unifying theories like string theory. To do this, I realize I will need a formal education in Physics. I have some background in Classical Mechanics and Thermodynamics as a mechanical engineer but am a little lacking in fundamental knowledge of other topics like EM (I have studied the basic wave propagation, electrostatics, AC/DC, magnetic induction in first year Physics & Electronics, but not Maxwell's treatment of EM waves), QM, GR, Statistical Physics, etc. Please note that the courses on CM & TD were from the mech engg department; I'm not sure if the physics department handles them differently. I would like to work towards a PhD in Physics - I'm turning 28 shortly. I have read ZapperZ's thread on taking practice GRE tests to evaluate yourself. I took that a while back and fared decently on a lot of topics – had to do a few 'Google searches' though. I would love to hear some personal experiences; of how you (or someone you know of) got into a Physics graduate program from another field. What kind of physics related coursework did you do in your Undergraduate studies? What hurdles did you face during your application process and later on, at the Graduate Program? Would you suggest I apply to a Graduate program in Physics and take up remedial courses in the remaining topics? Realistically, would a program accept this situation, considering the courses that I've taken? What are the admissions officers looking for, in this regard? Really appreciate any input..