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Originally Posted by worth
What i'm having trouble understanding and wasn't really aware of was the recycling that the universe does. In the program, they made it seem like there is a constant amount of matter. That atoms are neither lost or gained since the beginning of the universe, but rather rearranged and recycled. Atoms are blown up and fused all the time, and these combinations make up the elements. But these atoms have been around forever, and will always be around. Just in different combinations.
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Not completely accurate, as some matter is lost in the act of fusion; turned completely into energy.. and atoms = elements, combinations of elements make molecules. There are some processes which can completely change one atom into another kind of atom, but the general gist of the idea is right.
Quote:
Originally Posted by worth
Yet, if it is indeed true that no atoms are lost or gained, and that they are always around, then that means that the oxygen i breathe and the water i drink are made up of atoms that made up someone or something else on this planet or in this universe at some point.
They said on the program that basically, when you drink a glass of water, you are drinking atoms that were once a part of a star, which I understand, but I didn't fully comprehend maybe. And that when you breathe oxygen, you're taking in a couple atoms that passed through the most famous people to ever live.
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Yup, that oxygen or hydrogen atom in the water molecule had to come from somewhere, and the most common process to make oxygen is in the hearts of stars. Since that point it just goes on its merry journey, becoming part of a planet, being blown out to space again in a nova, becoming part of another planet, being eaten by Issac Newton in an apple, being peed out later, becoming part of the ocean, evaporating, raining down on your head...
Quote:
Originally Posted by worth
It doesn't totally make sense to me because don't atoms decay? We know they do, and they do at a predictable rate. So if they decay, I suppose they decay into a smaller atom? Atoms are not lost or gained, rather re arranged again. Is that correct?
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Radioactive atoms decay, but not all atoms are radioactive. Oxygen 16 (the most common form of oxygen, 8 protons and 8 neutrons) is stable, and does not decay. So unless something extreme happens to an atom of oxygen 16 (gets fused in the heart of a start to become a heavier element, gets hit by a cosmic ray, falls into a black hole) it'll stay an atom of oxygen for a looooong time.
Quote:
Originally Posted by worth
We all know everything came from the big bang. But that doesn't seem significant to me. It just seems so far removed. Like so much has changed since then. But when I heard that the atoms that were born then (few hundred million years after the big bang I think) are the exact same atoms that are floating around now and make up me and you, that kind of puts a different spin on things. Not so much an evolution into us, rather just a rearranging into life.
There's my rambling for the day.
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After the big bang there was pretty much only hydrogen, helium, and a little bit of lithium and a few other heavier elements, so all the heavier elements have been formed by other processes. Fusion in the cores of stars, and in the case of elements heavier than iron, formed in red giants and in the shockwaves of supernova.