I was reading the Wikipedia's page about "tired light", where we read that any alternative explanation to the observed redshift (described by Hubble's law) should be able to overcome several objections, among which "the time dilation associated to cosmologically distant events".
Cosmologically speaking, I only know the Shapiro delay, i.e. nothing to do with Hubble's law. And of course the time which light needs to reach us and to let us detect a given cosmic event. Moreover, in Einstein's relativity light is not itself affected by time dilation (only clocks are and, broadly, any macro/micro mechanical phenomenon). Even the gravitational redshift deals with the clocks used to measure light's frequency (different gravity on different clocks), not with light itself. So, what is the time dilation associated to "distant" cosmic events and how do we measure it?
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