That is, if the closest one we can observe is 1600 light years away, are we not observing these things as they were 1600 years ago? How do we know black holes didn’t just pop up for a brief time window, and now they are gone?
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How can one be sure that when you put a shoe in a shoe box that the shoe is really still in there? It’s important to remember that a black hole is a PREDICTION of general relativity (our modern theory of how gravity works), first put forth in 1916. Without that their idea simply wouldn’t exist. And then we observe them in modern times and they behave as the theory predicts. That is the situation.
One of course could ask, “How do we know that reality isn’t sprinkled with things that our laws of physics SEEM to exactly explain and model and we didn’t even know to look for until our theories predicted it but also have the additional feature that they randomly YOINK themselves out of existence to mess with us?”. The answer, I suppose, is we don’t.
How can one be sure that when you put a shoe in a shoe box that the shoe is really still in there? It’s important to remember that a black hole is a PREDICTION of general relativity (our modern theory of how gravity works), first put forth in 1916. Without that their idea simply wouldn’t exist. And then we observe them in modern times and they behave as the theory predicts. That is the situation.
One of course could ask, “How do we know that reality isn’t sprinkled with things that our laws of physics SEEM to exactly explain and model and we didn’t even know to look for until our theories predicted it but also have the additional feature that they randomly YOINK themselves out of existence to mess with us?”. The answer, I suppose, is we don’t.
The city I live in is pretty old. Due to its age, some buildings in the historical centre have slightly slanted floors. I’ve been in a house with such a floor. It’s not so that you’ll immediately notice, but put a tennis ball on the floor and it’ll roll away from you.
In other words, look at the floor and you won’t say something’s off about it. Look at the ball and you know not only will you find out that it is slanted, you will also quickly learn which side of the room is higher than its opposite side.
Same with black holes. Even if we can’t see them, we can see the effect they have on the things around them.
The city I live in is pretty old. Due to its age, some buildings in the historical centre have slightly slanted floors. I’ve been in a house with such a floor. It’s not so that you’ll immediately notice, but put a tennis ball on the floor and it’ll roll away from you.
In other words, look at the floor and you won’t say something’s off about it. Look at the ball and you know not only will you find out that it is slanted, you will also quickly learn which side of the room is higher than its opposite side.
Same with black holes. Even if we can’t see them, we can see the effect they have on the things around them.
The city I live in is pretty old. Due to its age, some buildings in the historical centre have slightly slanted floors. I’ve been in a house with such a floor. It’s not so that you’ll immediately notice, but put a tennis ball on the floor and it’ll roll away from you.
In other words, look at the floor and you won’t say something’s off about it. Look at the ball and you know not only will you find out that it is slanted, you will also quickly learn which side of the room is higher than its opposite side.
Same with black holes. Even if we can’t see them, we can see the effect they have on the things around them.
For the same reason we don’t assume you just popped into existence to post this question and then disappeared, there’s no evidence to suggest thats how things work, and lots of evidence to suggest its NOT how things work. Is it possible we are wrong? Sure, heck, its technically possible that the entire universe popped into existence 3 seconds ago with everything arranged such that it appears to us right now that its been around for a lot longer. But since we have no reason to suggest thats true, it doesn’t make sense to treat it that way.
For the same reason we don’t assume you just popped into existence to post this question and then disappeared, there’s no evidence to suggest thats how things work, and lots of evidence to suggest its NOT how things work. Is it possible we are wrong? Sure, heck, its technically possible that the entire universe popped into existence 3 seconds ago with everything arranged such that it appears to us right now that its been around for a lot longer. But since we have no reason to suggest thats true, it doesn’t make sense to treat it that way.
For the same reason we don’t assume you just popped into existence to post this question and then disappeared, there’s no evidence to suggest thats how things work, and lots of evidence to suggest its NOT how things work. Is it possible we are wrong? Sure, heck, its technically possible that the entire universe popped into existence 3 seconds ago with everything arranged such that it appears to us right now that its been around for a lot longer. But since we have no reason to suggest thats true, it doesn’t make sense to treat it that way.
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