Will Red Shift Eventually Make Distant Light Unobservable?

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Redshift will eventually make distant light unobservable as it shifts beyond the electromagnetic spectrum, marking the edge of the observable universe. This edge moves outward each year due to the expansion of space, allowing light from increasingly distant galaxies to reach us. However, redshift is a continuous process, meaning galaxies will not suddenly disappear from view. The confusion often arises from the relationship between the edge of the observable universe, redshift, and the speed of recession of distant objects. Ultimately, while the cosmic microwave background (CMB) will become undetectable, it will not exit the electromagnetic spectrum entirely.
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Since light emitted farther away from our point in the universe is more and more red shifted, would this mean that at a certain time we wouldn't be able to observe light further than a fixed distance since it's been red shifted beyond the electromagnetic spectrum?
 
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Yes. That's the edge of the observable universe. Every year, it gets several light-years farther out from us (not just 1 light-year, since space is expanding while the light is in transit).
 
Redshifted galaxies will become increasingly redshifted over time. They will never suddenly 'blink' out of view. Redshift is a continuous, not discrete, function.
 
@Chronos Eventually it will be redshifted out of the electromagnetic spectrum though right?
 
bcrowell said:
Yes. That's the edge of the observable universe. Every year, it gets several light-years farther out from us (not just 1 light-year, since space is expanding while the light is in transit).

Ben, I guess I have another misunderstanding that I need you to clear up. I thought the edge of the observable universe was the place at which objects exist from which emitted light has had time to reach us based on their position and their speed of recession from us and that we couldn't see beyond that point because the photons from those objects is now traveling away from us due to recession faster than they are traveling towards us due to their local speed. Clearly my concept IS tied up with red-shift so I'm having difficulty formulating my question well (another sign that I'm obviously confused). I guess at heart my belief is that the edge of the OU is based on time, not redshift and my question is an amorphous "HELP --- please get me unconfused"

Thanks.
 
The CMB will eventually move so far into the 'red' it will be cease to be detectable, but, never leave the EM spectrum.
 
https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
Why was the Hubble constant assumed to be decreasing and slowing down (decelerating) the expansion rate of the Universe, while at the same time Dark Energy is presumably accelerating the expansion? And to thicken the plot. recent news from NASA indicates that the Hubble constant is now increasing. Can you clarify this enigma? Also., if the Hubble constant eventually decreases, why is there a lower limit to its value?
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