|MadSci Network: Physics|
Dear Marc, You are leaving the realm of science, and entering the realm of philosophy. Science requires postulates, and experiments to test these postulates. One postulate is that the universe has not always existed. We test this postulate by determining the age of the universe. This is done by looking at the red shift of light from very distant galaxies. These measurements lead us to conclude that the universe does have a finite age, and is roughly 14 billion years old. That means that matter has not always been here and thus is not eternal. HOWEVER. None of us were present at the start of the universe. We do not know what really happened-- all we have are theories that have stood up to the data. All of the data lead us to conclude that the universe has not always existed, which forces me to tell you that matter is not eternal. I do not think you will be happy with this answer, nor with any I can provide you. Perhaps you can enlighten me as to what you really want to know-- I feel as if you are skirting an issue.
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