Olbers’s Paradox
“Why should the night sky be dark?”
This paradox was recognized in the 1820s by H. W. M. Olbers after he attempted to calculate the background light received from the stars. If the universe were infinite and homogeneous, then the flux from all background stars would be infinite, and the night sky would be bright. Olbers cited absorption by interstellar dust as the solution to this paradox.
Olbers’s paradox was subsequently used as an argument against an infinite universe; later the paradox was thought to be resolved by the discovery of the cosmological red shift, which weakens the contribution of distant galaxies so that the combined light of all galaxies is less than 1% of the background light from the stars in our own galaxy. It has now been suggested, however, that the true explanation rests on the finite lifetimes of stars. According to the cosmologist E. R. Harrison, the luminous emissions from stars are much too feeble to fill, in their lifetime, the vast empty spaces between stars with radiation of any significant amount. Credit for originating the paradox has recently been extended to an 18th-century Swiss astronomer, J. P. Loys de Cheseaux, who conceived it first but whose work was not widely known.
GROLIER ENCYCLOPEDIA
Olber’s Dust
Dust fails as a solution to Olbers’s Paradox just as it fails to be a good candidate for dark matter. In the most general sense, dust can be defined as a group of non-gaseous atoms and molecules that are in contact with one another. Since 99% of the universe is composed of hydrogen and helium gas, only one percent of matter is even capable of forming dust particles. It is true that a few common compounds such as water and hydrocarbons contain some hydrogen, but this does not substantially increase the amount of matter capable of becoming dust particles.
We know that the universe must contain a great many snowflakes because water is such a common simple molecule but certainly not enough to block starlight. Of the one percent heavier elements capable of becoming dust, very little of it resides outside of stars and almost none outside of galaxies.
Of the starlight that we observe here on earth fully 99% of it comes from just the stars in the Milky Way galaxy. This fact only serves to emphasize the paradox and show that the deficit of starlight is far greater than is commonly admitted.
Also, when we examine dust particles, we find that they are not random mixtures of various elements but rather are composed of just a few elements and compounds. For example, snowflakes are very pure ice crystals. They contain mostly water and almost no impurities of other elements. This means that in order for dust particles to form, atoms must first be consolidated within a star or planet where they can be sorted out into compounds and concentrated groups of atoms of a single element or similar elements.
Certainly, there is no gold dust out in the outer reaches of the cosmos. Even the smallest particle of gold dust contains billions of gold atoms. Gold is a rare element with only one stable isotope. How did those billions of individual Au-197 atoms all find each other in the first place to form a tiny speck of gold dust? The only way that individual atoms of gold could be concentrated is by gravitational separation within a condition of molten matter such as in the interior of a planet. Gold dust must be formed in the molten conditions of a planet and not in the gaseous and plasma conditions of a star. While gold atoms can be created in supernova explosions, only planets can gather them into gold dust and nuggets.
To become dust particles, groups of atoms and compounds must be redistributed out into outer space by some means such as a supernova explosion. This process of sorting atoms and then redistributing them into space as dust would certainly have a very limiting effect on the amount of matter that is available to make dust.
Another reason that dust is a poor candidate as a solution to Olbers’s paradox is because as dust absorbs light, it heats up and then emits photons back into space. In this way, dust would serve to scatter photons from distance stars but it would have very little effect on the total number of them actually traveling through space.
A second proposed solution to Olbers’s paradox is that the universe is far from infinite and has a finite number of stars than are incapable of producing enough light to make the interior of the universe bright. The problem with this idea is mostly philosophical in nature since it puts an unobserved limit on the distance that we should be able to see in the universe, even though as far as we look in any direction we still see a uniform number of galaxies.
This solution is usually combined with the idea that the universe has a finite age and therefore the stars have not been burning long enough to heat up the universe to the point where the night sky would be bright. However, as far as we are able to look toward this presumed edge of the universe and therefore into the distant past, we cannot see a place or time where the stars have not yet lighted up. Also, just as some stars grow old and die, other stars are constantly forming from the dust and gas in the universe.
This finite universe solution is contrary to observation because it requires that the observable universe be homogeneous only to the limits of our observation. Even though the distance that we can observe has grown greatly with the advent of the Hubble telescope, we still do not see any thinning of observable galaxies.
Expanding Inter-galactic Space
In light of these problems with explaining the paradox, the idea is often expressed that space itself must be somehow expanding. This causes the light from distant galaxies to be red shifted and that because of this shift, the photons from the distant galaxies have less energy than they did with they were emitted. Thus the universe is cooler that it would otherwise be.
In an expanding Newtonian space, the photons would keep their energy and momentum and stay in a group. The groups of photons will continue to get less intense as expanding space between them moves them ever farther apart.
In the expanding space-time conceived by the Big Bangers, it is not the space surrounding the photons that expands. Rather, it is the internal space and time within the photon’s structure. Not only does the space between them expand but also the photon’s wavelength increases at a proportionate rate.
The problem with this solution is that it uses a completely ad hoc, metaphysical assumption to explain away the paradox. The only possible reason to conceive of this brand of expanding space is to provide an enormous Z =1000 red shift for the CBR photons.
The major philosophical problem with the Big Bang’s idea of an expanding space is that it is strictly reserved for photons. This expanding space has caused the wavelengths of photons to increase by thousands of times but it has no effect on the space that makes up the wavelengths of the electrons and protons.
Also, this idea of expanding space violates at least two of the most precious tenants of physics; the conservation of energy and the conservation of momentum. This expanding space-time solution of Older’s paradox explains away the conservation laws by saying that energy and momentum can simply disappear over time and that the night sky is not bright because the photons that we observe from distant galaxies have lost most of their energy and momentum to expanding space as they travel through it.
Of course, there is no observation that supports this idea of expanding space and it is merely added to explain away Olber’s paradox. It is is said that the night sky is not bright because the intense photon radiation of the CBR has been dimmed by about 1000 times by the photon’s special kind of expanding space.
The 2.7° Cosmic Background Radiation fills the universe. The total energy of this radiation is very similar in quantity to the energy that we get from the photons that make up starlight here within the Milky Way. The average photon that we receive from starlight has an energy of about 2 eV and the average photon of the CBR has an energy of only about .0007 eV. This means that there are about 2/.0007=2,857 CBR photons for every starlight photon. If these blackbody photons had the same average energy as starlight photons from hydrogen atoms, the temperature of the universe would much hotter that it is today. At this temperature, the numerous visible photons from the CBR would make the night sky so bright that we would not be able to see the stars.
The analogy is often made between Boyle’s Law and the expansion of the universe. Just as the temperature within a gas-filled balloon decreases in proportion to the balloon’s expansion, so does the universe cool in direct proportion to its expansion.
However, the great flaw in this analogy, that is never acknowledged, is that the velocity and therefore the energy of individual gas molecules within the expanding balloon does not change. The decrease in temperature results from the reduced rate at which the gas molecules collide with one another and the increasing surface of the balloon, but the total energy within the balloon remains constant. In the same way, the temperature within a cavity filled with photons would decrease as the size of the cavity is increased, but this would have no effect on the wavelengths or energies of the individual photons, nor on the total energy within the cavity. Also, if the mixture and intensity of the photons within the cavity was just right to form a blackbody distribution curve for a given temperature, this blackbody distribution would not be maintained as the cavity was enlarged because the wavelengths of the photons would be too short to match the blackbody curve for the reduced temperature.
The standard Big Bang model tells us that both the 2.7° CBR photons and starlight photons were mostly produced by hot hydrogen gas at a similar temperature. Then, in order to explain Olber’s paradox of the dark night sky, it makes the metaphysical assumption of a special kind of expanding space into which the energy of photons can gradually disappear without a trace. I say “special” because this expanding space has no effect on the wavelengths and energies of other particles such as protons and electrons. Clearly, there seems to be no other way to explain Hubble red shift and the low 2.7°K temperature of the CBR except with the assumption of this peculiar kind of expanding space.
A Solution to Olber’s Paradox
A far more elegant solution to both Olbers’s paradox and the Hubble red shift is obtained when we consider the observed gradual change in the mass ratio between the electron and proton (E/P ratio). In the past, when electrons were more massive than they are today, hydrogen atoms had larger Bohr radii and produced photons with much longer wavelengths and lower energies. The “red shifted” photons that we receive from distant galaxies were emitted at those longer wavelengths and have not changed during their long journey through space. By the same token, the photons of the 2.7° CBR were emitted when the electron/proton mass ratio was only 1/157 and the temperature of the universe was 2.7°K. Neither the wavelengths of these photons nor the temperature of the universe has changed from these values up to the present day. This solution is derived from observation and does not require that vast amounts of energy mysteriously disappear into empty space.
In conclusion, it seems clear that Olbers’s paradox presents a formidable psychological, philosophical and experimental barrier to the standard model of physics and to the Big Bang cosmology and its proposed external universal expansion of the universe. It is the Big Bang’s conclusion that in the distant past the night sky was very bright from all the photons of the CBR. Then, in the billions of years since their formation, each of these photons lost 99.9% of its energy and momentum through a mysterious and otherwise unprecedented process called the expansion of space-time.
The only conceivable way that this solution of Olber’s paradox could be made to work is by arbitrarily abandoning the most fundamental laws of physics; the conservation of energy, the conservation of momentum, the conservation of mass/energy, equal conjugation of charge, and the constancy of the speed of light.
In contrast, if we consider the internal expansion of the electron in place of the external expansion of the space within the universe, we arrive at a completely natural explanation of Olber’s paradox that obeys all natural laws and doesn’t require any new assumptions. The night sky is not bright because of the decreasing mass of the electron. The photons emitted by atoms in the distant past had much longer wavelengths and much less energy than photons emitted by those atoms today. The photons of the CBR have the same wavelengths and energies today that they had when they were created.