It also makes me wonder if everything is actually the same? I know it’s a silly question, but are all quarks the same (composition wise) if so, does that mean that at our smallest core, we are made up of the same thing? Does this also mean that if not, that there is always going to be variance even to our smallest level? I suppose this question is asking more about what exactly is the composition of the smallest possible particle, and is there really an end?
In: Physics
We think quarks are the smallest because it’s so far the smallest denomination we’ve been able to observe, but we’re still exploring.
Quarks stick together to make other particles, like protons and neutrons, which make atoms, and so on.
Asking if they’re all the same is like asking if each type of legos are the same. Quarks have different types, called flavors, but they all seem to have some common qualities. So, in a way, everything is made of similar stuff, but it’s arranged differently, like how you can make different things with the same lego bricks.
There are two types of quarks and three generations of each type. We only see the up and down quarks normally, the higher energy versions, like the charma and strange decay, and the top and bottom are even higher energy. So all matter is made up of up and down quarks. 2 ups and a down make a proton, and two down and an up makes a neutron. Electrons are elementary like quarks.
As far as we know quarks aren’t composed of anything. Same as electrons and photons, they are elementary
> How do we know things don’t just get infinitely smaller?
We don’t.
Quarks are not the same, there are 12 different types of quark (and anti-quark) in the Standard Model. They are similar, but have different properties.
It’s also important to note that when we get down to these scales ideas about “things” start to get a bit fuzzy. Systems can end up being more of a big messy ball of probabilities than fixed things with fixed properties.
We can’t be sure, but we can predict how quarks as elementary particles should behave, and so far all measurements agree with these predictions. It would be a pretty weird coincidence if quarks were composite particles that just happened to behave in the same way.
All quarks of a specific type (e.g. all up quarks) are identical.
All science, *always*, includes an invisible “…to the best of our knowledge” at the end.
So: things don’t get infinitely smaller than quarks *to the best of our knowledge*.
If someone proves that they *do* keep getting smaller, then the statement will change. Science *loves* being proven wrong! It means we learned something new.
If we could break it down, our current models require more energy than is in the universe to break it down. It already takes an absurd amount of energy we can’t harness to even keep a quark in isolation. The energy density of the universe is so low at this point that it likely will never happen again.
We believe that there is a quark field, and a lepton field, and quarks and leptons are just disturbances in that field. The type of disturbance determines which type of quark/lepton it is.
We find new particles by smashing particles into each other and find the trace of the path left behind by the different parts. If quarks are made up of other stuff, that should fall apart too if the energy is high enough (i.e. speed with which we smash the particles into eachother), but we haven’t observed that yet. So either, they are not made up of other parts, or the energy we tried isn’t high enough.
Modern physics has a concept called the Planck Length, which is 1.616255×10−35 m. One way to think about it is that is essentially a limit of “smallness” beyond which we could never look. To grossly simplify a complicated subject, according to the laws of physics as believed today, just like there is nothing that can exceed the speed of light, there is absolutely no possible way we could ever measure or observe anything at such very small sizes.
https://en.wikipedia.org/wiki/Planck_units#Planck_length
Latest Answers