The expansion of the universe
When we talk about the expansion of the universe, we don’t mean that galaxies are
simply moving away from each other, but that space itself is expanding. Phil Plait uses
the example of a rubber ruler that expands, the space between tick marks gets bigger.
If we replace the tick marks with galaxies, we appear to see them moving away from
us. Does this theory explain what Vesto Slipher saw with his redshift measurements?
Explain.
When we talk about the expansion of the universe, we don’t mean that galaxies are
simply moving away from each other, but that space itself is expanding. Phil Plait uses
the example of a rubber ruler that expands, the space between tick marks gets bigger.
If we replace the tick marks with galaxies, we appear to see them moving away from
us. Does this theory explain what Vesto Slipher saw with his redshift measurements?
Explain.
Sample Solution