I always enjoy a discussion about semantics, but only when both parties are very clear about the fact that it's semantics they're talking about, and not fundamental nature of existence. I'm very wary of people trying to use physics to further an ontology, as physics almost by definition allows for multiple, completely equivalent descriptions of reality. That's not to say I think physics teaches us nothing about how the universe really works, but I don't think you can conclude from his interpretation of the mathematics of QFT that particles (whatever they are) don't exist, just as much as the Fermat principle[0] doesn't imply that light has a sentient mind which seeks out the shortest path. There exists a consistent, fully equivalent interpretation of (non-relativistic or relativistic) quantum mechanics that includes particles at the core of its ontology, Bohmian mechanics[1]. I'm personally not an adherent of it, but it shows that by nature, it's very hard to use physics to show what something fundamentally is.<p>Besides, the article doesn't define clearly what it means by particle, which is a priori just an English word, nor does it justify it well. I don't share the authors' problem with the excitations of a field being spread out all over the universe (by virtue of them being momentum-eigenstates). It's discrete, has a mass, has a momentum, and energy and interacts as a whole. The article calls these properties necessary but not sufficient, but doesn't explain why this doesn't suffice.<p>Particles are at least a useful abstraction. They emerge naturally at the classical level, interactions between fields are even at extremely high energy levels still very localised, electrons "scatter" a lot like they're bouncing off other particles, they leave neat tracks in bubble chambers, excitations of fields are discrete even at the lowest level, ... Feynman diagrams[2] are extremely handy, even if they don't "actually" happen, but are just a term in the series expansion of an interaction Hamiltonian between two fields.<p>What's the use of contorting oneself to the limit to fit every observation in a single mold, a field. Sure, classical particles are nothing like what we see at the quantum level, but classical fields are absolutely nothing like the fields in quantum field theory either. Why pick one term over the other?<p>0: <a href="https://en.wikipedia.org/wiki/Fermat%27s_principle" rel="nofollow">https://en.wikipedia.org/wiki/Fermat%27s_principle</a>
1: <a href="https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory" rel="nofollow">https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory</a>
2: <a href="https://upload.wikimedia.org/wikipedia/en/f/fb/Feynman-diagram-ee-scattering.png" rel="nofollow">https://upload.wikimedia.org/wikipedia/en/f/fb/Feynman-diagr...</a>