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Message: <blockquote data-quote="Umbran" data-source="post: 5699814" data-attributes="member: 177">As noted by freyar, while the wavelength is a length measured in the X direction, and the electric and magnetic fields oscillate in the Y and Z directions, they are not lengths in those directions like the wavelength is.  We say say light has a wavelength in meters or centmeters, but the amplitude is not in meters of centimeters.Not as I think you mean that question, and I understand Relativity, no.  We do not experience time "going forward" due to the expansion.  It is perhaps more accurate to say there's time to go forward into because of the expansion.  Much like there's space to fly a ship through because of the expansion.There is a relationship between space and time - the two are bound together as what we call "spacetime", so you cannot affect one without affecting the other.  This is what Einstein's relativity is all about.That though has been expressed, and we can see the intuitive sense in it.  If time starts as zero, and expands as the universe grows, if the universe again shrinks, the extent of the Universe in the "time direction" has to shrink, so things will have to move back from t= a bazillion back towards t=0, essentially moving backwards.Freyar may be able to correct me if I am wrong, but I think that violates the laws of thermodynamics.  There are processes in the universe that are not time-reversible, so that what has been done cannot be undone.  If we went from Big Bang, to expansion, to squeeze, to Big Crunch, in the second half of that process, you'd not just see the history of the first half run backwards in the second.  You can think of this as the extent of the universe in time shrinking, but the point it shrinks to isn't t=0, but instead t= a bazillion - we crunch in time to the far end, not the beginning.Which is apt to be a bit moot, for us in this universe, as the current indications and understanding suggests are that we are not going to have that squeeze - it looks like the Universe will continue expanding forever.</blockquote>

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