Every particle that could conceivably interact with the matter/energy that makes up humans, and the immediate reality we inhabit, has been defined by the Standard Model of Physics. This does not mean that other particles do not exist, but that such particles would not interact with us at all, or so weakly so as to have no measurable effect.
I would have said, off the top of my head, that the Standard Model of Physics was defined by us, not the other way around. What exactly is it, and how does it define things, other than in the sense of being a useful mental model we use to describe the universe?
I don't understand what "other particles" is meant to refer to here. Other than what? And what ARE these other particles to which you refer, if they aren't the ones we usually encounter? And what has any of that to do with theology? A universe in which God were made of particles, spooky or otherwise, would rather contradict the notion of an immaterial realm/power/force which seems to integral to most religious perspectives. Obviously, Christians do believe that God is at least occasionally made of particles - else, why the Eucharist - but not to be synonymous with them. At least, not in any version of the mythos that I have ever heard.
So if any gods exist, they would not have the ability to interact with us.
If God is essentially immaterial, but immanent in the material, he or she or it is interacting with us whenever we interact with anything. Isn't that what immanence means?
The Standard Model describes
all of the interactions that influence particles. The only unknowns in the model occur at very large scales, or at very high energies.
A human is composed of 'particles' and 'forces', both of which are precisely described by the mathematics of Quantum Field Theory. One of the requirements of the theory is the interchangeability of mass and energy, as described by Einstein's famous equation. This says that mass is energy, and vice-versa - so if you concentrate enough energy in one spot, any particles with a mass equal to, or lower than, that amount of energy will arise. The model lists all of the possible particles, and describes their properties - mass, half-life, decay products, etc.
As a result, we can thoroughly and accurately test the model by putting a lot of energy into one spot, surrounded by detectors, and looking at what particles are created, and their energies.
We can be completely confident that this process will generate examples of every particle and force that can exist within the range of energies of our experiments. If the theory is flawed, we will see results that differ from the predictions of theory - so if, for example, a force or particle not described by the Standard Model could possibly exist at the energies we have tested, then that would show up as a disagreement between theory and observation.
Using particle accelerators, we can look at some VERY large energies. We can also use astrophysical data to examine low energy interactions (such as gravity), that only become measurable at large scales.
This gives us an upper and lower bound, between which we can be confident that no interactions of any kind occur, apart from those described by the Standard Model. At this point in time, the low energy bound implies interactions are completely understood for all entities smaller than several light years across; and the high energy bound implies interactions are completely understood for all entities larger than sub-atomic particles.
For a hypothetical god to influence a human via an unknown force (or particle, or field), would require either that the human in question occupies several cubic light years of space; Or that he could withstand energies similar to those found in atomic explosions. Neither condition is compatible with life.
Of course, we could hypothesise a god that interacts with our reality only via the forces we already know about, in accordance with the Standard Model. But if we do so, our hypothesis predicts that those divine interventions will be easily detectable using simple scientific techniques. And we detect no such interventions.
Either a 'soul' is easy to detect; Or it is incapable of interaction of any kind with its owner; Or it is fictional. No other possibilities are compatible with modern physics, and none of these are compatible with any intervention by gods, nor with an afterlife, psychic powers, or a whole range of other mystical ideas.
Of course, it's possible that tbe Standard Model is wrong. But for it to be wrong enough to rescue theism and/or dualism would imply that none of our modern technologies are understood by their inventors or users. Everything we have invented since the industrial revolution would have to operate according to principles we have completely failed to understand, and our success would have to be down to stupendously good luck - luck on a level that would make winning every lottery ever
drawn seem like a trivial coincidence.
Theists are often very keen to point out that nothing in science is proven or certain. They are right - but some things are far more certain than others, and the likelihood that the Standard Model is wrong in a way that would render interactions between god and man a possibility, is considerably lower than the likelihood that the moon is made of green cheese, and we just got all our observations that should have shown that fact, wrong.
It's literally insane to accept both the Standard Model and the existence of a god that interacts with humans. Picking one of these two exclusive positions is necessary for a reasonable person; And picking the one that has been exhaustively tested and has passed every test, over the one that's based entirely on speculation, rumour and 'revelation', but has never been seen experimentally, is a no-brainer.
It's over. Atheism is correct, theism is wrong. The moon's not a dairy product, and there is neither a soul nor an afterlife outside fiction.
Fortunately for the world's religions, physics is hard, maths is hard, quantum physics is harder still, and most people don't take the time and effort to learn these things.
But not knowing quantum physics doesn't make it incorrect, or avoidable. Your computer works only because of the success of a theory that implies that gods are nonexistent. That remains true whether or not you (or anyone else) understands it. And this is not secret knowledge; Anyone who puts in the time and effort to learn the maths and physics involved is completely free to test it for themselves - and those who do are in a constant state of striving to show that the Standard Model is wrong, or inaccurate. Showing that it has even the tiniest flaw is sufficient to ensure a Nobel prize. Even at the high and low energy ends of the spectrum, where there's still room for debate and possibly surprising observations.
We have had the best minds in the world working for a century and more to try to find errors in this model. They publish everything for criticism by the entire body of their colleagues. Anyone who wants to have a crack is allowed to do so. None have succeeded.
Meanwhile, the god hypothesis relies on a bunch of contradictory anecdotes that are largely incapable of being tested or falsified. There's literally no reason to accept any theistic claim over other, competing theistic claims. No theist has ever leveraged their understanding to develop a new and effective technology or way of life. There are no prayer based computers, or GPS systems, or power plants, or transportation systems, or really anything demonstrably superior to their secular equivalents.
The Standard Model implies atheism. The "competition" between physics and religion to explain reality is like a match between Mohammed Ali at his prime, and an asthmatic octogenarian amputee with poor eyesight and a glass jaw.
In my experience, most folks on secularist fora are only comfortable attacking other religious perspectives; when pressed to defend their own, they usually insist that they "simply lack a belief in God" and are therefore making no concrete claims that must be defended. You are being refreshingly straightforward, outright claiming that a particular quality of God cannot exist given what you understand of physics. I suspect a lot of atheists would agree with you, but they are usually afraid to voice such opinions in debate with non-atheists. Much harder to defend than to attack. More vulnerable. And I suppose unnecessary, if you believe that atheism wins as long as conservative Christianity loses.