Here's a fundamental question about a fundamental particle existing within the fundamentals concerning all things temporal: How old is an up-quark? If particles can be created out of nothing, then an up-quark, an example of a fundamental particle, has a finite age. However, if matter cannot be created out of nothing, as the First Law of Thermodynamics states, then matter like the up-quark (and also energy), has always existed and thus even if our Universe had a beginning, it was in the context of a beginning from pre-existing stuff.
My debating theist, MG, insists that the Universe had a beginning and that was due to their being a First Cause, and the 'cause' of the First Cause was, of course God. There could have been no actual existence of matter / energy as well as of time and space before that First Cause. Therefore, MG will have hell freeze over before he concedes that there was a before-the-beginning-of-our-Universe, a before-the-beginning that involved matter, energy, time and space. Alas, hell has just frozen over since there was a before the Big Bang as we shall shortly see. A frozen hell is even more the case if there never was a beginning to matter / energy as well as no beginning to time and space. That totally does away with the need for a creator, in other words MG's God. Of course I argue exactly that point – that hell has frozen over – and use as a primary argument that particles are temporally infinite.
MG – “I'm referring to the life of a single particle, which you claim has existed for an infinite amount of time.”
JP – If a particle, like an up-quark, can neither be created nor destroyed, then by pure logic it has to have an infinite lifespan.
MG “Even if the life of a particle is infinite… “
JP – The moment you acknowledge that a particle can have an infinite lifespan you totally demolish your own First Cause, cause. It becomes a lost cause! You are a finite event. The stuff that makes you up is NOT a finite event but an ever ongoing process. The stuff that makes you up existed before you were an event and will exist after you cease to be an event, that is after you turn to dust or ashes. Now until such time as you can actually demonstrate for me – in practice, but I'll settle for any theoretical means that scientists would endorse – that something like a particle can be created from nothing (and thus have a finite lifespan), and I don't care what kind of universe you postulate – open or closed – I'll just go along with the most obvious of obvious conclusions, that being that the Cosmos is temporally infinite. End of story.
MG – “… it [a particle] persists across a series of events throughout its life.”
JP – Which is a ‘life' that is infinite so the series of events it crosses is infinite too.
MG – “The problem is that there is no way it could have completed an infinite number of events PRIOR to the current event that it's in the midst of right now.”
JP – If at every moment of existence, everything in existence has experienced their existence ‘now', then it's not surprising that everything in existence has made it to this point in time – which is ‘now'. That applies no matter how far back your existence goes, even if it goes infinitely far back.
MG – “The particular up-quark that you claim has always existed (because you think it could not have been created) must have actually gone through an infinite number of events prior to the one that is currently going on in its frame of reference… So, you are faced with simultaneously saying that something has completed an actually infinite number of steps AND that infinities cannot be completed since they go on and on.”
JP – Up-quarks cannot be created or destroyed according to theory, to experiment, to observation. You can negate that statement by actually creating or destroying one. Negating that possibility, therefore up-quarks have always existed. They are and always will be of infinite age. But they have clearly made the infinite journey to the here-and-now. That is not under dispute. So, in the battle between theoretical metaphysics and actual observation, back actual observation.
MG – You claim that there are particles with infinite lives, so do it from their perspective… If a particle has had an infinite life prior to this point, then it has traversed an infinite number of events and has reached the end of that infinite set of PAST events (given that all such events already happened prior to the current event that the particle is currently going through; aka, prior to the “dividing line” for that particular particle).
JP – Nothing succeeds like success and you can't deny the success of the temporally infinite stuff of the temporally infinite Cosmos being present and accounted for in the relative here and now. You also can't deny that there is no actual experimental or theoretical means by which that stuff can be created from no-stuff so therefore my claim that the stuff of the Cosmos is temporally infinite has to be true and therefore the Cosmos containing that stuff (as a closed system) is also temporally infinite. Therefore there is at least one flaw in your argument.
MG – “We agree on point one, infinite series do not reach endpoints (they don't even have any endpoints), but somehow you disagree that, by definition, the term “past events” refers to the series of events which occurred prior to now… what exactly does “past event” mean to you, then, if not what the standard definition is?”
JP – A “past event” is a happening that involved some motion, some change and had some duration, a duration that was measured by some units we invented which we happen to call units of time. That “past event” however when it actually happened was a current event or a now event (current or now being that ever ongoing division between what happened and what will happen). You'll note that for a current event to become a past event that there was no termination point or endpoint involved with respect to that current, now past event, otherwise you wouldn't be having this current event, soon to be a past event. Since each event is usually considered to be an event of finite duration, well that's why we can label it an event instead of something eternally ongoing, like an up-quark. You are a finite event; an up-quark is an ongoing ‘event' of infinite duration. That you are a finite event doesn't mean there isn't an infinite number of finite events, past and future (since you can't pin down “The Present Moment” or “current” or “now”).