Well, if we consider the universe as a closed, isolated system, then the law of conservation of momentum should kick in.(adsbygoogle = window.adsbygoogle || []).push({});

P = MV

We know that Hubble's law states that the velocity of bodies on an astronomical scale is increasing and P is a constant, so that means M must be decreasing. However, the first law of thermodynamics states that the amount of matter/energy in the universe is also a constant.

Therefore, if the universe is a closed system, P and M must be constant, ergo V must be constant too and thats absurd to say by the means of Hubble's law. Can I be refuted?

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# Is this not mathematical evidence that the universe is an open system?

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