3 ms·
Could black holes also be masking an infinite number of stars? Stephen Hawking notes in his book "A Brief History of Time" that we know that there aren't infin
by ythn 9y ago
Could black holes also be masking an infinite number of stars?
Stephen Hawking notes in his book "A Brief History of Time" that we know that there aren't infinite stars because otherwise the night sky would have no patches of darkness since an infinite number of stars would imply that you could shoot out an arbitrary ray from earth and it would always reach a star.
However, black holes (lots of them!) could trap light and obscure line-of-sight stars.
- coliveira 9y agoThis line of reasoning works only in a static universe. In a expanding universe, stars can move apart faster than the speed of light. Thus there might be a lot beyond the observable universe that can never be detected.
- Neeek 9y agoI mean... isn't it still technically correct though? We have an opaque horizon of light, it's just all in the microwave spectrum.
- burkaman 9y agoThis is Olbers' paradox, and I don't think you need black holes to explain it: https://en.wikipedia.org/wiki/Olbers%27_paradox https://en.wikipedia.org/wiki/Olbers%27_paradox
- Neeek 9y agoI've always wondered about the CBM in this instance. Isn't that technically an opaque horizon of light? I understand that it's not stars per se, and that there is technically stuff "beyond" that, but doesn't that count as a "bright" night sky? Just not in the visible spectrum.