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Comment: Re:What can you do about it? (Score 4, Insightful) 333

by Khashishi (#49721127) Attached to: Genetically Engineered Yeast Makes It Possible To Brew Morphine

A lot of people who abuse drugs do so because their lives suck. Maybe they don't care about their long term health because they have no hope for the future and don't care if it kills them. Efforts to penalize them for using drugs simply makes their lives suck more and their future even more hopeless.

Comment: Re:Flat does not imply infinite. (Score 1) 235

by Khashishi (#49656315) Attached to: Shape of the Universe Determined To Be Really, Really Flat

We can't actually take a trip around the universe. I'm talking about a thought experiment in which you mathematically translate some position around the universe. In a Mobius strip, you flip around when you go around the universe. Since you never cross a boundary while going around the Mobius universe, the laws of physics must stay the same as you go around, so the laws of physics have to be independent of parity.

Of course we don't know that the universe doesn't have boundaries. It's just a reasonable guess. And, yes, we don't know the universe is homogeneous. Some of the conjectures for the shape of space, like the Picard horn, aren't homogenous at all.

Comment: Re:- or we are just very small? (Score 1) 235

by Khashishi (#49654421) Attached to: Shape of the Universe Determined To Be Really, Really Flat

No cosmologist thinks the universe was just a single point in size. This is an error in how the big bang is explained to the public. Also, it is error-prone to try to compare the rate of expansion of the universe to the speed of light. These things are not comparable. The expansion of the universe is a scaling of the universe. For example, in one second, 1 meter becomes 2 meters. Then 1 parsec becomes 2 parsecs. You can't compare this to a speed. 1 meter going to 2 meters in one second is a lot slower than the speed of light, but 1 parsec going to 2 parsecs in one second is a lot faster. These refer to the same rate of expansion.

Comment: Re:Flat does not imply infinite. (Score 1) 235

by Khashishi (#49654357) Attached to: Shape of the Universe Determined To Be Really, Really Flat

If we assume that the universe is spatially isotropic (which implies homogeneous), it really cuts down on the possible shapes. If we assume it is also orientable (which only matters if our universe is finite), then there really are only a few options. As far as I know, these are: infinite flat Euclidean space, positively curved finite 3-sphere (3d analog of a normal sphere which is just the surface of a ball), and negatively curved infinite hyperbolic space.

I think the universe must be orientable because there is experimental evidence of CP symmetry breaking. Which means if the universe is nonorientable, it must flip charge, parity, and time or disagree with experiment. Hard to see how time can become flipped by making a trip around the universe, with homogeneity and the second law of thermodynamics being held everywhere.

It seems like the easy answer is an infinite flat space, but the problem is that an infinite universe also seems infinitely unlikely in some weird metaphysical sense (not a rigorous thought pattern). Perhaps isotropy is broken at large scales. After all, time has a preferred direction; why not space?

Comment: Re:Will wormholes work FTL in this flat universe? (Score 1) 235

by Khashishi (#49654225) Attached to: Shape of the Universe Determined To Be Really, Really Flat

The universe appears flat at large scales. It isn't flat on small scales, as evidenced by gravitational lensing by massive objects. Wormholes probably don't exist, but if they do then they just affect the small scale structure of the universe, not the large scale.

The other line moves faster.

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