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No. If you could there would be a few galaxies which would be about equidistant from us along both paths. Therefore we would notice a few double copies of the
by IIAOPSW 8y ago
No.
If you could there would be a few galaxies which would be about equidistant from us along both paths. Therefore we would notice a few double copies of the same galaxies. It would be similar to standing in the middle of two mirrors. IIRC scientists have already ruled out a universe with a "radius" less than some ridiculous number (like billions of light years).
There. Just saved you a click. This is old and well know. Why is Forbes writing about it now?
- craftyguy 8y ago>Why is Forbes writing about it now? The general public doesn't know this, it's a very slow news week, or both.
- stcredzero 8y agoIn the case of things like this, it's as much because people have erroneous ideas left over from outdated science journalism, as it is from people just not having any information or inclination to care. (Sherlock Holmes's reaction to the information that the Earth goes around the sun.)
- gyre007 8y ago> Why is Forbes writing about it now? My totally random guess is the reason why theyre writing about it now is that it might be part of PR for the First Man movie about Neil Armstrong being the first man on the moon.
- heavenlyblue 8y agoNope. Our visible universe is bounded by the expansion of space that happens at the speed of light. That means we can only see a subset of the universe at any time.
- gpderetta 8y agoNot only that, due to expansion, the subset is getting smaller by the second!
- ikeboy 8y agoBut if you travel at less than the speed of light you'd never pass that anyway
- isaiahg 8y agoBecause of expansion we'll likely never be able to travel to any of the galaxies in the universe except our local neighborhood. But it's still worth studying those galaxies from a distance to learn more about our universe.
- PopeDotNinja 8y agoIf you traveled at the speed of light, you'd still never make it to the edge of the universe. The edge of the observable universe is moving away from us faster than the speed of light. [1] [1] https://en.wikipedia.org/wiki/Observable_universe https://en.wikipedia.org/wiki/Observable_universe
- charlesism 8y agoSo a beam of light with a head start, half-way across the universe from you, could "wrap around" and eventually reach you. But the beam of light couldn't "wrap around" and reach itself, because the universe constantly moves the goal post before light beam gets the chance?
- heavenlyblue 8y agoYes. The fact is that does it not prove or disprove the fact that our universe is wrapped around - it may be either way. The parent's point is invalid because we wouldn't be able to see the wrapped around light even if it existed.
- karmakaze 8y agoExpansion is not limited to the speed of light. Two points in space may be 'moving apart' faster than the speed of light because they're not moving, space is being created in-between. The more space there is in between, the faster the rate of expansion between the points.
- heavenlyblue 8y agoI am not saying expansion of the universe is limited to the speed of light. I am saying the boundary of the observable universe is defined at the points where the expansion of space reaches the speed of light.
- empath75 8y agoBelieve it or not, everyone doesn’t know everything that everyone else knows.
- deleted 8y ago[deleted]
- bmurphy1976 8y ago> Why is Forbes writing about it now? Why not? Look who the author is: Ethan Siegel. He has a blog (https://medium.com/starts-with-a-bang https://medium.com/starts-with-a-bang) and a podcast (https://soundcloud.com/ethan-siegel-172073460 https://soundcloud.com/ethan-siegel-172073460). He basically does a Dear Abby type column based on astronomy and physics topics. He takes difficult concepts and tries to break them down into something the lay person can understand. Quite frankly, I think he's pretty damn good at it and we should be happy Forbes is publishing his stuff for a wider audience.
- EGreg 8y agoCan you explain how one implies the other?
- jobigoud 8y ago> scientists have already ruled out a universe with a "radius" less than some ridiculous number (like billions of light years) How is billions of light years a ridiculous number? Even the observable universe is bigger than that, so the full universe could be many many times bigger. Since you can't see past the observable universe you wouldn't be able to see the double copies.
- stcredzero 8y agoWe know from analysis of the cosmic background radiation, that the universe is at least 150 times the size of the observable universe, which puts the minimum diameter of actual universe in the range of 10 to 15 trillion light years. It could be much larger than that, however.