The oldest cosmological paradox considers the fact that the night sky should not appear dark in an infinite, ageless Universe. It should glow with the brightness of a stellar surface, because, if we look far enough, we would see some star.
Possible explanations have been considered to get rid of the problem. Here are the most obvious:
- There’s too much dust to see distant stars. (This was Heinrich Olbers’ attempted explanation, in 1826. If true, it showed the universe was young! Olbers had several predecessors, including Kepler and Jean-Philippe de Chéseaux in the 1720s… But a German name beats a French one, in the matter of Anglo-Saxon fame….)
- The Universe has only a finite number of stars.
- The distribution of stars is not uniform. So, for example, there could be an infinity of stars, but they hide behind one another so that only a finite angular area is subtended by them.
- The Universe is expanding, so distant stars are red-shifted into obscurity.
- The Universe is young. Distant light hasn’t even reached us yet.

Galaxies Galore! Hubble Ultra Deep Field 2014. Other Hubble Pictures Within our own Milky Way giant galaxy, show nearly solid wall of stars, that is, the Olber’s effect!
The first attempted explanation is wrong, because dust will heat up too. If it didn’t heat up, that means the universe is young. (So Olbers could have predicted that! Or a finite universe!)
The premise of the second explanation may technically be correct. But that means that the universe is finite. The third explanation may be partially correct, because matter is very far from being uniformly distributed in the universe. We just don’t know how severe the lumping is: there are Great Walls (of galaxies!), Great Attractors (of galaxies!), Great Blobs (of quasars!), etc. If the stars are distributed in a lumpy way, then there could be large patches of empty space (which there is, because they have been seen!), so the sky could appear dark except in those directions.
The final two possibilities are presently viewed as correct by common cosmologists, and a cause of what’s observed. Some computational arguments suggest that the finite age of the Universe is the larger effect. We live inside a spherical shell of “Observable Universe” which has a diameter equal to the (“Cartan’s comoving”) distance covered by the expanding universe during the lifetime of said Universe. That’s 95 billion light-years, according to the most esteemed conventional computation. Objects which were far enough to start with, are too far away for their light ever to reach us.
The resolution of Olber’s paradox is found in the combined observation that 1) the speed of light is finite and 2) the Universe has a finite age, i.e. we only see the light from parts of the Universe which at some point in time where less than 15 billion light years away. Everywhere far away, say the conventionalists, we should see the fiery light of the Big Bang, and we do, they add: this is the 3 degree Kelvin background cosmic radiation. Initially it was hyper hot, but the light got stretched in the last 13.8 billion years, by the expansion of the universe, so now it appears very cold… (Except that I have a different explanation for it!)
And now for a word from our sponsor:
***
Subquantum Cosmology’s Olber’s Paradox Resolution:
How does my own SubQuantum Patrice Reality (SQPR) theory fits in all this? Very well. In my theory, the universe also expands (that’s called “Dark Energy”, and it’s a direct experimental fact). But the universe expands slowly (that’s how I resolve the problems “cosmological inflation” is supposed to resolve, but doesn’t!).
As the universe slowly expands, every single photon wave gets stretched, as in the usual Big Bang Lemaitre metric. However now that effect is not enough to solve Olbers paradox (the expansion being too slow). So another effect comes into play: light ages, from the Sub Quantum Reality (SQPR). The average photon coming from far away is so spread-out, when it hits an object, somewhere, that part of said photon is too far to coalesce with the rest, thus gets disconnected from the main singularization, and is left, in the average, as a 3 Kelvin remnant.
***
Notice that Olbers and his predecessors could have deduced much from the simple fact that the sky was not all like the surface of the sun. Olbers said: that’s because there is dust. But ultimately dust would turn as yellow and hot as the sun too. It didn’t, either because the density of stars was not constant… Or then the universe was only 6,000 years old, or so (;-)).
This being said, dust should not be ignored. Recently, it was proclaimed a proof of cosmological inflation had been found, and eminent cosmologists such as inflationistas like Guth were already attributing to themselves the Nobel Prize, but it was only an effect due to galactic dust.
Conclusion: a simple observation can very well contain revolutionary science, when, and if, logically processed. But one needs courage to do this. An obvious candidate is the collapse of the “wave packet” in Quantum Physics. Attempts to ignore, or deny that collapse, have brought the “Many Worlds” Derangement Syndrome affecting physics (and not just physics, thanks to mood transmission…)
Patrice Ayme’