"We are made of star stuff" - surely not all the particles?

I was having an unpleasant insomnia occurrence a couple of nights ago, and this question drifted into my lack-of-sleep addled mind.

Given (and is that a given?) that all atoms in existence were created by the “big bang”, or in stars and/or supernovas, does that mean that the protons, neutrons and electrons that make up the atoms that make up my fingernail are all essentially as old as the universe?

Are the quarks that make up those protons & neutrons “immortal” (for want of a better word)?

Actually I realise that that “given” is not true; atoms can be created via nuclear decay etc.

But the main thrust of my question was intended to be about the sub-atomic particles. Are they billions of years old?

Nucleosynthesis does not happen at random and if you take the six most common elements and consider their sources you will find the source of this claim.

Oxygen: Exploding massive stars
Carbon: Exploding massive stars or exploding white dwarfs
Hydrogen: The Big Bang
Nitrogen: Dying low mass starts and exploding massive stars
Calcium: Exploding massive stars and exploding white dwarfs
Phosphorus: Exploding massive stars and exploding white dwarfs


The fact that these new atomic nuclei from pre-existing nucleons doesn’t change that. Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons.

Related to decay the amount of carbon-14 from the decay of nitrogen-14 is tiny, and that nitrogen-14 was originally “made” inside stars even if it is now a rare cosmogenic isotope.

Almost all nucleon were probably produced during the big bang, but not all are required to have been so. But supernova and stellar nucleosynthesis is where most of the “stuff” you are made of was born.

When the baryons were formed there were probably a much higher ratio of protons to neutrons than there are in your body, so it depends on whether you consider the neutron formed a continuation of the proton it formed from or not. I’d assume there is some pair production going on inside of stars that would also kill off old electrons and replace them with new ones.

But the majority of protons in your body ought to have been protons from the start.

It’s not like we can readily do the experiments, but it is expected that a black hole would transform quarks in the very long term by converting their energy into Hawking radiation (and presumably some other transformation in the short term, but we couldn’t observe that.)

Post big bang after matter could coalesce virtually everything was hydrogen with He and heavier being trace contaminants. Where else would the heavier stuff come from? You can thank some long dead Population III star for you and everything around you.

Read the OP, people! He’s talking about quarks, not oxygen atoms.

I had to address the reference to a statement which was being used outside of it’s intended domain.

And myself and other posters have answered his question.

Yes most quarks that make up those protons & neutrons in today’s atoms were bound together during the big bang.

Yes matter can be created and destroyed, but it is not common for that to result in long lived nucleons.

And Yes most of what you are “made of” is still “star stuff”

It really depends on what you mean when you say “the same quark”. If an up quark turns into a strange quark by emitting a virtual W+, and then the strange quark turns back into an up by emitting a W-, is that the same quark? If a red up quark turns into a green up quark by exchanging gluons with another quark, is that the same quark? What if it only maybe does one of those things (i.e., there’s a path by which it does that, but the amplitude is less than 1)?

My understanding is that subatomic particles really should not be thought of as actual physical objects, but rather as mathematical concepts that happen to exist in the real world.

Wheeler proposed to Feynman that all the electrons and positrons in the universe are actually exactly the same particle. When it travels forward in time, we call it an electron, when it travels backwards in time, we call it a positron. This is called the one electron universe. You can play the same game with quarks and anti-quarks. I don’t think this was ever taken seriously (even by Feynman), but it is a cool concept. Feynman did use the notion of positrons being electrons going backward in time in his formulation of Quantum Electrodynamics (QED).

I don’t think that getting absorbed by a black hole and having that energy emitted as Hawking radiation can even be argued to be immortal, and I don’t see how the one electron universe is compatible with it.

Take it to the limit where a black hole evaporates completely - in just 10[sup]66[/sup] years or so, a Sol-sized black hole will convert 100% of the quarks initially added into radiation. They clearly weren’t immortal.

I realised that I would be out of my depth but that… that is where I start drowning.

OK, then, suffice to say that the endpoint of that line of questions is that there isn’t any way of defining “the same quark” that’s meaningful enough to be able to even ask the question in the OP.

So there is a probability that some quarks in my fingernail are billions of years old, and some probability that some of them are mere seconds old?

Because not every quark is going to flip… it should be a fairly random thing, right? Similar to nuclear decay, no one can say which atom is going to decay but we can predict the average rate of decay.

Is there a way to predict the average rate at which quarks change into “strange” quarks & back again? Is there even a way to measure such a thing?

Given the probabilistic nature of quantum mechanics, it’s not even possible to define.

Suppose that you have two quarks interacting, and for simplicity let’s say that they’re an up and an anti-up. You know that an up and an anti-up go into the interaction, and an up and an anti-up come out of the interaction. Well, there’s a few ways that could happen. The two particles could get close to each other, exchange a vector boson (a particle that carries a force) such as a photon or gluon, and then go apart again. In that case, presumably you’d say that you still have the original particles. Alternately, the two particles could annihilate into a vector boson, and then after some short time that vector boson could turn into a new quark-antiquark pair. In that case, presumably you’d say that you don’t have the same particles you started with. Or you could have more complicated interactions, involving multiple vector bosons, but let’s not worry about that.

So, given any individual interaction, can you say which one of those two possibilities happened? In fact, so far as we can tell, what actually happens in any interaction is all of them, each with varying amplitudes. The particles both are and are not the original particles, and it doesn’t matter.

Here’s a nice chart from the Astronomy Picture of the Day site; it’s the periodic table color-coded to indicate each element’s origin. Also from the site is this explanation:

It’d be a bit like throwing a rock into a stream, which makes waves that then run into other waves and rocks, are absorbed, reflected, refracted and diffracted, and combines with other streams. Then at the far, far end of the river, seeing a ripple, and asking if it is the same wave.

Except that sometimes, the recombining ripples stir a pebble loose off of the river bed, toss it up into the air, and then it falls back down, making more ripples.

I’m sure there are trace amounts of radionucleides in the environment released my atmospheric nuclear testing that could be absorbed by the body.