When you see these particle collider experiments that have confirmed the existence of the various types of quarks, then these experiments are displaying those quarks briefly before they disappear. So what's actually happening to the quarks when they disappear? Are they decaying? If so, then what are they decaying into? Are they binding back together with other quarks? If so, then where did those other quarks come from? They say that in deep space, there is still a certain density of free hydrogen available out there. But there seems to be no similar availability of free-floating quarks, even in deep space. If you have a quark floating freely in deep space, then what's going to interact with it, to snatch it up? I'd read that it takes infinite energy to separate quarks from each other, but if that's the case, then how were quarks shown to exist unless they could be briefly separated for long enough to identify them? Is it really right to call a quark a particle, if it can't independently exist?