[–] [deleted] 1 point 0 points 1 point (+1|-1) ago
[–] darkhunt333 2 points 0 points 2 points (+2|-2) ago (edited ago)
What. All matter is the age of the universe. More accurate to say that this rock formed 4b years ago.
[–] Myrv 0 points 1 point 1 point (+1|-0) ago
If we take the definition that matter is any particle with a non-zero rest mass then no, not all matter is the age of the universe. Matter can be created from photons (which given the non-zero rest mass condition are not matter). That said, what percentage of the the universe is new matter? I'm not sure but I guessing an infinitesimal small amount.
[–] TexasVet 0 points 1 point 1 point (+1|-0) ago
So you are saying that when a hydrogen atom gets fusioned into a helium atom inside a star that it is not considered new material? I get it that the quarks and gluons inside the protons are still the same particles, but surely there has to be somewhere that we draw the line when we say that all matter has existed since the big bang.
[–] oedipusaurus_rex 0 points 2 points 2 points (+2|-0) ago
OP's post was accurate even assuming that your complaint is valid.
Saying a rock is 4 billion years old is the same as saying that it formed 4 billion years ago.
A rock is a rock as long as it doesn't weather into aggregate (some of it will, but the aggregate part becomes sand/dirt), and as long as it doesn't melt. Gneiss is incredibly hard. It's basically tempered granite/schist.
[–] smokratez 5 points -3 points 2 points (+2|-5) ago
God made the best rocks.