I'm a senior undergrad, and I verbally committed to sticking around with my current research prof for a PhD at the beginning of the school year. However, I'm now really enticed by the graduate program of another school, and I'd like to at least apply to the other school.
However, I don't know how to ask my research prof--whose lab is the technically-juciest part of my CV--for a rec letter. He has already recommended me to 2 fellowships, so I know he has a letter ready for me.
Should I just not ask my advisor for a letter? How would a grad committee feel about the lack of input from the closest research adviser? I have a 3.8 and 3 years of hands-on experience in different labs (no publications) and student groups, so I feel like I have a decent shot at getting into the other school without my adviser's recommendation, but I'd like to get your thoughts.
More broadly speaking, is it okay for me to even apply to the other school? On one hand, I feel guilty about possibly reneging on my statement to work with him, especially since I've had some unproductive spats in his lab and I feel indebted to him for keeping me on. On the other hand, I don't feel guilty because he told me he doesn't have any long-term funding left for me (hence the fellowship applications). Moreover, one of the fellowship proposal's depended on the lack of progress in a certain field which my prof and I later discovered has been secretly progressed very rapidly by a government lab.