1. Isotropic? yes.(adsbygoogle = window.adsbygoogle || []).push({});

2. Homogeneous? Historically, the scale of homogeneity seems to be a moving target. As ever larger structures are observed, the scale of homogeneity is set just past the horizon, so to speak.

My real problem comes from the following thought experiment. Actually a pseudo thought experiment since it can not be performed.

Suppose the universe has a slight positive curvature. It is then closed and contains a finite amount of stuff. Now, by magic, we take one hydrogen atom from every cubic kilometer and make it disappear.

The curvature could now be exactly zero, or slightly negative. There are now two alternatives:

A. The universe could spontaneously transmute into an infinite flat or hyperbolic space containing an infinite amount of stuff.

B. The universe could spontaneously transmute into a flat toroidal or closed hyperbolic space, still with a finite amount of stuff.

My (scientifically unjustified) opinion of this pseudo experiment is that the universe should be finite. Perhaps I am just taking the model too seriously.

Cheers, Skippy

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# How seriously do you take the FLRW model?

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