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An infinitely large observable universe is not possible, however an infinitely large and infinitely old universe is still possible with dark sky at night.
by Kranar 5y ago
An infinitely large observable universe is not possible, however an infinitely large and infinitely old universe is still possible with dark sky at night.
- mabbo 5y agoHowso? If the universe is infinitely large and old, and light works as well believe it does, then light should come from all directions. That's the entire point of this paradox. Light as we know it moves without limit. If anything is blocked by it, the blocking object would heat up until it glowed just as brightly.
- lurquer 5y ago'Infinitely large' isn't a prerequisite to the paradox. Rather, it's an infinite number of stars. Or, more precisely, an infinite number of stars spread out rather uniformly.
- Kranar 5y agoIt's not possible to have an infinite number of stars in a finite region. However, you could have a finite number of stars that form a cover over some point.
- lurquer 5y agoI agree. I was just pointing out that the thread keeps referring to ‘infinitely large’ universe. Perhaps it’s just shorthand for ‘infinite number of stars’. No big deal. Obviously, if you had 10 stars in an infinitely large universe, there is no ‘paradox.’
- ravi-delia 5y agoRapid expansion looks the same as infinitely large and finitely old, in this case. Our universe, as it turns out, also seems to be expanding in addition to being finitely old. If it were not, the sky would slowly be getting brighter, but it will in fact only get darker from here on out. The space beyond the edge of the observable universe will be forever out of reach, even to light.
- dragonwriter 5y ago> Light as we know it moves without limit. Black holes say no.
- ravi-delia 5y agoConsidering gravity decreases at the same rate as brightness, that's a cure that would be significantly worse than the disease. Black holes would need to significantly outnumber stars, and we really don't see that.