Apr 7, 2020 07:51 PM
http://physicsbuzz.physicscentral.com/20...ional.html
EXCERPT: . . . We live in a universe that physicists describe as having 3+1 dimensions–three dimensions in space and one in time. But was a 3D world a foregone conclusion? Could complex life have emerged and survived in a 2+1 (2D) world? This question is at the heart of a paper recently published in the journal Physical Review Research by James Scargill [...]
Some scientists have proposed that a universe with three spatial dimensions is the most stable kind of universe or has other physical advantages. This may be the case, but physicists haven’t been able to show it mathematically. Another way to approach this question is to add a bit of philosophy. [...] Could intelligent life have emerged in a universe with any other number of dimensions? If the answer is no, then of course we live in a place with three dimensions; if we didn’t, we wouldn’t be here to ask the question. If the answer is yes, then exploring the possible scenarios could reveal new insight on how and why the universe evolved as it did.
There’s a pretty convincing anthropic argument against life in a universe with more than three spatial dimensions. Newtonian gravity predicts that orbits aren’t stable in a universe with additional spatial dimensions. Without orbits, you don’t get galaxies, stars, planets, atoms, or life. Stable orbits are possible in a universe with two spatial dimensions, but there are other anthropic arguments against the possibility. Here are two of the most common:
• General relativity isn’t consistent with a 2D universe
• Complex life can’t form in a world where things like neurons don’t cross paths.
Scargill’s new research addresses these two arguments using a “big picture” approach. [...] He doesn’t present complete theories, or even show that life in a 2D universe is definitely possible. Instead, he demonstrates that the common anthropic arguments against the existence of life in a 2+1 dimensions actually don’t rule out the possibility.
[...] This research raises so many fascinating questions. What conditions are necessary for complex life? On the flip side, what would rule out the possibility of life? If life could have existed in 2+1 dimensions, why do we exist in 3+1? What would life look like in 2+1 dimensions? (MORE - details)
EXCERPT: . . . We live in a universe that physicists describe as having 3+1 dimensions–three dimensions in space and one in time. But was a 3D world a foregone conclusion? Could complex life have emerged and survived in a 2+1 (2D) world? This question is at the heart of a paper recently published in the journal Physical Review Research by James Scargill [...]
Some scientists have proposed that a universe with three spatial dimensions is the most stable kind of universe or has other physical advantages. This may be the case, but physicists haven’t been able to show it mathematically. Another way to approach this question is to add a bit of philosophy. [...] Could intelligent life have emerged in a universe with any other number of dimensions? If the answer is no, then of course we live in a place with three dimensions; if we didn’t, we wouldn’t be here to ask the question. If the answer is yes, then exploring the possible scenarios could reveal new insight on how and why the universe evolved as it did.
There’s a pretty convincing anthropic argument against life in a universe with more than three spatial dimensions. Newtonian gravity predicts that orbits aren’t stable in a universe with additional spatial dimensions. Without orbits, you don’t get galaxies, stars, planets, atoms, or life. Stable orbits are possible in a universe with two spatial dimensions, but there are other anthropic arguments against the possibility. Here are two of the most common:
• General relativity isn’t consistent with a 2D universe
• Complex life can’t form in a world where things like neurons don’t cross paths.
Scargill’s new research addresses these two arguments using a “big picture” approach. [...] He doesn’t present complete theories, or even show that life in a 2D universe is definitely possible. Instead, he demonstrates that the common anthropic arguments against the existence of life in a 2+1 dimensions actually don’t rule out the possibility.
[...] This research raises so many fascinating questions. What conditions are necessary for complex life? On the flip side, what would rule out the possibility of life? If life could have existed in 2+1 dimensions, why do we exist in 3+1? What would life look like in 2+1 dimensions? (MORE - details)