Correct-Answer to Question #6:
Is the Universe really expanding?

Q.  Is the Universe really expanding?
A.  No. This idea is based on a misconception, that the red-shift of distant galaxies means they are moving away.

Q.  What is the red-shift of galaxies?
A.  Lines in the spectrum of light from distant galaxies show that the light has lost energy in its journey from its source -- the lines shift toward the red (lower-energy) side.

Q.  And these red-shifts vary with distance?
A.  Yes. As the light travels farther, it loses energy at a fairly steady rate with distance.

Q.  Didn't Edwin Hubble prove that the Universe is expanding?
A.  No, he showed that red-shifts occurred, and that they increased with distance. But he didn't believe that this had anything to do with galaxies moving away.

Q.  Where is this explained in more detail?

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