composite particles de Broglie wave length

edpell

Does de Broglie wave length apply to composite particles? For example a very low momentum neutron does it have a very large wave length? Or do we think in terms of the three quarks that make up the neutron? The three quarks do not have low momentum they are banging back and forth inside the neutron and so have a shorter de Broglie wave length.

Which way is the right way to think about this?

Runner 1

I too have wondered about this. My quantum mechanics professor used the example that a basketball has a very small wavelength, but if the individual particles that constitute the basketball have much larger wavelengths, well, then what's going on? (What does this mean experimentally?)

Bill_K

When you're dealing with a system that has more than one degree of freedom, you have to think in terms of phase space. There's an (x,p) pair for each degree of freedom and a de Broglie wavelength for each. So for a slow neutron there's a center of mass coordinate X and a corresponding momentum P and de Broglie wavelength h/P, while the individual partons that make up the neutron each have their own coordinate x_i, momentum p_i and wavelength h/p_i.