Question

The particles of the SM are defined and differentiated by whether or not they interact with various fields, in what way they interact with those fields, and to what degree they interact with those fields. These fields give any given particle species its definitive characteristics.

During the fraction-of-a-second epochs of the very early universe, particles did not interact with these fields, or they did not interact with them in the same way, or they did not interact with them to the same degree as they did in the Quark Epoch or any subsequent time period.

Now, bosons are definitively differentiated from fermions by their spin, so prior to the acquisition of spin, it seems to me to follow that all particles were spin zero particles, which makes them, by definition, bosons. Prior to the acquisition of color charge, the particles that are now quarks would have better fit the definition of leptons. Prior to the acquistion of mass, none of the massive particles of the SM could have existed, at least not under the defintions they have in the SM. And prior to the acquisition of electric charge, electrons and positrons seem to fit more readily into being defined as a different type of neutrino.

It seems from my understanding of X and Y bosons that they are "ancestral" to W1, W2, W3, and B bosons, and in turn, those bosons are "ancestral" particle species to W+/- bosons, Z bosons, and photons.

So I will try to clearly state my question:

Did the particles of the SM evolve from hitherto undescribed ancestral or primordial particle species, for instance, quarks diverging/evolving from "proto-quark" leptons-like species, electrons and positrons diverging/evolving from "proto-electron" and "proto-positron" neutrino-like species, and fermions diverging/evolving from "proto-fermionic" boson-like particle species?

Maybe this is a better way to ask:

Could there have been unknown spin zero bosons that were ancestral to all fermions, could there have been unknown lepton species that were ancestral to both the known leptons and to quarks as well, and could there have been unknown neutrino species and quark species that were ancestral to positrons/electrons and the different flavors of quarks, respectively?

It seems that with all other types of evolution, things branch rather than evolve linearly. I wonder if we are looking at the evolution of the early universe a little bit wrong, because we categorize the particles of the first epochs as "fermions in a massless state" or "electrons in a chargeless state" even though we already know that saying something like "chargeless electron" is like saying "protonless hydrogen." It contradicts the very definition.

I have tried to ask this question before, so thank you for your patience with me if someone sees it as redundant, but, given the answers I have received, I have perceived that I have asked my question poorly, since to me, the answers seemed to answer OTHER questions than the one I intended to ask. If this is not the right forum for this type of question, I apologize, and would appreciate any direction anyone has toward an appropriate forum for this type of discussion.

Answer 1

The evolution of subatomic particles in the standard model from a highly energetic early universe to the distinct entities we observe today involves the acquisition of properties like mass, spin, and charge, possibly from ancestral primordial particle species without such characteristics.

Step-by-step explanation:

The question posed concerning the evolution of subatomic particles in the standard model (SM) of particle physics touches on complex and speculative areas of particle physics. Originally, in the very early universe during epochs such as the Inflationary Epoch and the Planck Epoch, particles did not interact with fields such as the Higgs field, in the manner they do now. This suggests that the properties of these particles, such as mass, spin, and charges, were not the same as those that define the current set of SM particles.

In the earliest moments, particles may not have had definitive characteristics such as spin or mass. This leads to the hypothesis that there might have been ancestral or primordial particle species with no mass, spin, or other charges, which later evolved to acquire these properties as the universe cooled and the fields became more differentiated. For example, a 'proto-quark' or 'proto-lepton' might have been the precursors to our known quarks and leptons. Similarly, gauge bosons such as the X and Y bosons could have been ancestral to the W and Z bosons and photons.

Particles such as quarks are unique because they interact through quantum chromodynamics, while leptons do not. Hadrons such as protons and neutrons are composed of quarks, and leptons include electrons and neutrinos. Both of these families of particles have evolved into the distinct entities we observe today. The leptons, hadrons, and carrier particles like photons and gluons emerged as distinct categories that interacted with the fundamental forces in specific ways defining their current forms.