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rpsls t1_iwr0qh8 wrote

Reply to comment by Chimalez in Dark matter may be information itself by newsphilosophy

I remember reading that they had found galaxies which had collided and the bigger one stripped the smaller galaxy of its dark matter. That these small post-collision galaxies were spinning more like what would be expected with standard physics. Did that not pan out, and if it did, how would a galaxy stripping another of “information” even work?

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ryschwith t1_iwrmape wrote

That’s still the case (the Bullet Cluster is frequently brought up here) and is generally where every “what if dark matter isn’t matter” theory falls apart. I don’t really understand this particular theory enough to say whether or not it resolves this.

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Chimalez t1_iwr5jdo wrote

If you assume that based on the laws of conservation of mass and energy, information cannot decay into a nonexistent state, then if the dark matter of one galaxy collided with the dark matter of another galaxy, the one with more dark matter (aka more "information" in this example) would be subject to less overall decay due to having more energy available during the collision, or perhaps would even absorb the structure of the lower-entropy dark matter. I realise I brought up entropy here and it may not seem relevant but if information is really structured in the universe then maybe entropy is what dictates the interactions like what you described above.

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