 A crucial issue is whether a quantum field theory is fundamentally about fields or particles—or something else entirely. While the most common choice is fields (see Struyve 2010 for an assessment of a variety of possibilities), Bell’s is particles. His proposal is in fact the basis of a canonical extension of Bohmian mechanics to general quantum field theories, and these “Bell-type quantum field theories” (Dürr et al. 2004 and 2005) describe a stochastic evolution of particles that involves particle creation and annihilation. (For a general discussion of this issue, and of the point and value of Bohmian mechanics, see the exchange of letters between Goldstein and Weinberg by following the link provided in the  Other Internet Resources  section below.)