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Can the expansion of the Universe effect be explained by contraction of the overall matter instead? That is, all material objects are in fact contracting, due to what the universal space seems (and only seems) to be expanding. Are there any theoretical arguments or experimental data that preclude replacement of the universal space expansion by the universal matter contraction as an explanation tool of the nature of the very process?

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This alternative that you mention is very imaginative, but It poses several problems. For example, if all matter is contracting, galaxies and clusters or any large scale structure would eventually collapse, and this is not something we have detected. In addition, the expansión of the universe not only affects matter, but also light: photons loose energy, which is equivalent to say their wavelengths are redshifted. A contraction would imply that light is blueshifted, again an effect that we have not observed.

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Can the expansion of the Universe effect be explained by contraction of the overall matter instead?

No. If the universe was not expanding, the tempeture of the of the universe would reamin the same. And this is not the case. Also according to GR the universe cannot be stationary. It should be either expanding or contracting.

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The answers proposed by others here are correct and they give you intuitive reasons why they are correct.

I’ve thought about similar questions before.

Another way of asking it, if I were to try and guess what you are proposing, would be: “Could dark energy expansion be explained by proposing that the Planck distance is not actually a constant?”

A good resource for thinking about this would be Leonard Susskind’s YouTube Stanford lectures on cosmology. At some point he derives Planck constants from scratch, and gives good explanations for why these things are constants and why they don’t vary.

https://youtu.be/P-medYaqVak

Lots of equations, but always explained well.

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