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The aether was a medium that nineteenth and very early twentieth century physicists believed was necessary to allow the propagation of light. Prior to that, all known methods of conveying waves from one point to another (water, sound) required something through which they moved.

The luminiferous aether was problematic from the beginning, because it had to have bizarre physical properties. For example, as a general rule, the more rigid a material is, the faster it transmits waves. The speed of sound in air is only about 330 meters/sec at sea level, but it is over 6000 meters per second through steel (and more than twice that through diamond.) So, the aether had to be tremendously rigid, since the speed of light through the supposed aether was 50,000 times faster than the speed of sound through steel.

Despite that requirement, it had to offer no mechanical "drag" through space, because the motions of the planets (for example) were perfectly accounted for by Newton's Laws, which assumed that space was effectively empty.

The natural question then arose: does the speed of light change as the earth moves around the sun? It should, because for one part of the year light transmitted through the aether should be moving with the aether, and for the other half of the year, it should be moving against the aether. In fact, because the earth travels in roughly circular motion around the sun, the speed of light should rise and fall sinusoidally as the earth moves through the aether. In a series of brilliant experiments, two American Physicists, Albert Michelson and Edward Morley, proved that the speed of light never changed, regardless of the orientation of the observer or location of the Earth. It is one of the most famous negative results in history, and spelled the eventual end of the theory of the "luminiferous aether."

Fermions and bosons don't have anything to do with this really. In quantum mechanics, there is a requirement that the wave functions of systems of particles must be either symmetric or antisymmetric when the particles trade places. This must happen because the sum total of the square of the wave function indicates the likelihood of finding a particle somewhere in space, and that squared value must not change when two particles are "swapped." [They still have to be somewhere, even if they trade places!]So, the wave function can only change by a factor of +1 (symmetric) or -1 (antisymmetric) when the particles are interchanged. [AND ... Those are the only possibilities, because -1 and +1 are the only numbers that square to 1.]

Particles which make up systems with antisymmetric wave functions are called fermions. (Named after the Italian/American Physicist, Enrico Fermi; probably the most underrated physicist of the twentieth century: both a brilliant theoretician and equally fantastic experimentalist -- a very rare combination in the last 200 years.) Very loosely, a fermion is any material particle: electrons, protons, neutrons, quarks, ... and their antiparticles.

Particles which make up systems with symmetric wave functions are called bosons (Named for Satyendra Nath Bose and Albert Einstein, who developed some of their statistical properties.) Again very loosely, particles which are either: 1) even number combinations of more basic particles or, more famously, 2) the so-called "gauge bosons" which transmit forces throughout the universe are bosons. Gravitons, gluons, photons, the W and Z particles, and the Higgs boson are all bosons. So is, for example, Helium 4 (because it's made up of an even number of fermions: 2 protons, and 2 neutrons.) But not Helium 3, because it's made up of an odd number of fermions (3 in all, 2 protons, and 1 neutron.)

So ... clearly fermions and bosons exist.

And despite the silly claims of science "journalists" and popularizers that quantum physics "describes things that are very small," the truth is that whether a system is made up of bosons or fermions has a great deal to say about its large-scale behavior. For example, nearly ALL of the properties of metals are attributable to the fact that their free electrons are fermions. (Fermi himself developed this theory.) The behavior of many elements near absolute zero changes dramatically, depending on whether their isotopes are bosons (like He4) or fermions (like He3.)

This universe could not possibly exist in any kind of recognizable form if the photon were not a boson.