Why doesn’t the Copernican Principle apply to inferences of the age and origins of the universe? Some cosmologists argue that we live in a privileged era of the universe when we can infer its origins because we can still observe the red shift of distant galaxies. After these galaxies pass beyond the event horizon, observers existing X billion years from now in our galaxy wouldn’t have the data to deduce the universe’s expansion, its apparent age, and therefore the Big Bang.
Yet the Copernican Principle denies the assumption that any privileged observers of the universe can exist. What if it turns out instead that the universe appears to have the same age and history, regardless of how much time passes according to how we measure it?
The copernican principle is a statement of ignorance—it’s a caution against making up the claim that we’re at the center of the universe. This is to be distinguished from the positive knowledge that the universe is a uniform blob.
I suspect when it comes to the evolution of the universe we are starting to run up against the edge of the reference class that the Copernicaln principle acts within and start seeing anthropic effects. See here—star formation rates are falling rapidly across the universe and if big complicated biospheres only appear within a few gigayears of the formation of a star or not at all, then we expect to find ourselves near the beginning despite the universe being apparently open-ended. This would have the side-effect of us appearing during the ‘priviliged’ era.
But again, why doesn’t the Copernican Principle apply here? Perhaps all observers conclude that they live on the tail end of star formation, no matter how much time passes according to their ways of measuring time.
First, the event horizon doesn’t work that way. You will never see what Andromeda will look like a trillion years from now, but in a trillion years, you will see Andromeda. It’s just that you’ll see what it looked like a long time ago. You will eventually get to the point where it’s too redshifted to see.
Second, the universe won’t be able to support life forever, so it can be assumed that we’d exist before it gets to the point that it can no longer support life.
Yet the Copernican Principle denies the assumption that any privileged observers of the universe can exist.
I don’t think it denies the assumption in most forms. It might be better to state the Copernican Principle as assigning a low prior that we are privileged observers. That low prior can then be adjust to a reasonable posterior based on evidence.
Why doesn’t the Copernican Principle apply to inferences of the age and origins of the universe? Some cosmologists argue that we live in a privileged era of the universe when we can infer its origins because we can still observe the red shift of distant galaxies. After these galaxies pass beyond the event horizon, observers existing X billion years from now in our galaxy wouldn’t have the data to deduce the universe’s expansion, its apparent age, and therefore the Big Bang.
Yet the Copernican Principle denies the assumption that any privileged observers of the universe can exist. What if it turns out instead that the universe appears to have the same age and history, regardless of how much time passes according to how we measure it?
The copernican principle is a statement of ignorance—it’s a caution against making up the claim that we’re at the center of the universe. This is to be distinguished from the positive knowledge that the universe is a uniform blob.
I suspect when it comes to the evolution of the universe we are starting to run up against the edge of the reference class that the Copernicaln principle acts within and start seeing anthropic effects. See here—star formation rates are falling rapidly across the universe and if big complicated biospheres only appear within a few gigayears of the formation of a star or not at all, then we expect to find ourselves near the beginning despite the universe being apparently open-ended. This would have the side-effect of us appearing during the ‘priviliged’ era.
But again, why doesn’t the Copernican Principle apply here? Perhaps all observers conclude that they live on the tail end of star formation, no matter how much time passes according to their ways of measuring time.
First, the event horizon doesn’t work that way. You will never see what Andromeda will look like a trillion years from now, but in a trillion years, you will see Andromeda. It’s just that you’ll see what it looked like a long time ago. You will eventually get to the point where it’s too redshifted to see.
Second, the universe won’t be able to support life forever, so it can be assumed that we’d exist before it gets to the point that it can no longer support life.
It will merge with Milky Way in a few billion years. It will ceased to exist as an independent galaxy nearby.
I don’t think it denies the assumption in most forms. It might be better to state the Copernican Principle as assigning a low prior that we are privileged observers. That low prior can then be adjust to a reasonable posterior based on evidence.