RE: Direct Coupling of the Higgs Boson to the Top Quark Observed
I will try to shortly answer with what is unfortunately my limited knowledge of elementary particles, standard model and modren physics.
The Aether model of the universe from the 19th century had a very different idea from what 21st century physics tells us about the universe. The aether was a postulated medium for the propagation of light.
It was known that sound or more generally mechanical waves propagate through physical medium such as air, water, stone, metal... The propagation in this case is caused by particle to particle interactions - in air or liquid particles randomly push eachother, and a wave is nothing more than a non-random movement caused by some external force. The same applies to solid bodies or crystals - neatly and tightly packed atoms interact with each other like tiny springs.
It would be great if the same model could be used for light waves. So the aether was postulated. It was supposed to be a continious medium which we couldn't see, feel or interact with in any way. Its only role was to carry light waves. This aether model would cause big problems because it would mean that there was some absolute space (the one in which the aether did not move) - the theory of aether was disproved by the famous Michelson - Morley experiment (I suggest reading about it) which was repeated more precisely many times after the original experiment. Today we know that photons are a quantum of the electromagnetic field. They are in some way a "materialization" - a particle of a electromagnetic field, and the medium via which the photon propagates is its own electromagnetic field !
So where does the Higgs boson come in this story, and what does it say about the aether model of the universe ? The Higgs boson doesn't revive the aether model of the universe. There is an analogy between the Higgs boson and photons... The Higgs boson is a "materialization" - a particle of a Higgs field, just like the photon is a particle of a electromagnetic field.
I am not qualified to speak in more detail about the Higgs boson and its field but I can definitely say that there are proper Feynman diagrams of the Higgs boson - top quark interactions.
I hope this answer helps a little bit :)