We think of the universe in terms of what we can see. The stars, galaxies, gas clusters and particles that light up our night have intrigued and fascinated us since the beginning of time. However it is the dark universe, what we cannot see and what we cannot fathom, that makes up the majority of our sky. If we cannot see it and we don’t know what it is, how do we know dark matter exists and who really cares anyway?
The story of our dark and mysterious universe begins with Fritz Zwicky. Like many “brainiacs” before him, he had nothing better to do one day than to contemplate the universe or his navel or both at the same time. He found through complex and extremely boring math stuff, that the universe has a lot more mass than what can be accounted for by what we see. This “missing mass” problem was the birth of the idea of dark matter or as I prefer to call it “awesome nothingness”!!
“There is a theory which states that if ever anyone discovers exactly what the universe is for and why it is here, it will be replaced by something even more bizarre and inexplicable. There is another theory which states that this has already happened.” - Douglas Adams
The Universe is a Jar of Jellybeans
We think of space as a vacuum, so where does all this awesome nothingness that is dark matter fit in? Just think of the universe as a jar of jellybeans filled up mostly with black ones and a few of the coloured variety. The yummy colours are the baryonic matter we see and the black ones are our dark matter. They may taste yuk but they hold the universe together and may ultimately decide the fate of the jar.
What exactly are these black jellybeans? Many more brainiacs have come up with a number of speculations or what I call “untheories”, that is, through lots of careful observations and more wiggy math stuff, you have no idea what it actually is, but you have a really good idea what it isn’t.
M.A.C.H.Os vs W.I.M.Ps
Dark matter is not the baryonic matter of protons and neutrons that we know and feel comfortable with. It does have to be something and there are a few ideas. Dark matter could be made up of M.A.C.H.Os also known as Massive Astrophysical Compact Halo Objects, or a complicated way of saying brown dwarf stars and black holes. Now I am as fond of a good singularity as the next person, but black holes are so last millennium. In my opinion M.A.C.H.Os get beaten up by W.I.M.Ps also known as Weakly Interacting Massive Particles that are subatomic in nature, have a low mass and rarely interact with normal matter. Wouldn’t you know it wimps take over the universe. Next geeks shall inherit the earth!
Dark Fluid, not Just a Good Cup of Coffee
So we accept the existence of dark matter and it may seem pretty wimpy, but that is not the end of the story. Our universe is not static but expanding. The Big Bang may explain this expansion, but how do we account for this expansion accelerating?
This is where Dark Matter could be gravitationally repulsive, which creates a form of Dark Energy. Dark Matter and the subtle effects of this energy act as a kind of Dark Fluid that fuels the universe itself; pretty much like coffee keeps us going.
The repulsive gravitational effects of dark energy has implications for us beyond just powering the expansion of the universe. That’s right my pointy eared trekkie fans, Dark fluid could make warp speed and interstellar travel a reality. Two physicists from Baylor University have suggested that utilizing dark energy generated from the manipulation of dimensions, can create a bubble that can propel us at faster than light speeds. The basis of this innovative theory is that rather than moving an object at incredible speeds, you manipulate space-time to expand behind and shrink in front of it. This effectively moves space around the object. I just love people who think outside the space ship.
The Ultimate Fate
Dark matter and Dark energy may just be the most fundamental stuff in the universe. It will take eons for us mundane humans to get our heads around the concepts and implications and it is easy to say “So what?” Dark matter and its behavior, may give us a greater understanding of the origins of the universe and it’s ultimate fate. The amount of Dark energy generated is accelerating the universe but where does it all end? When thinking of Dark Fluid we have to ask, “how much is really being generated and will it end with the universe being Open, or expanding forever, or will gravity catch up and be pulled back into a Big Crunch?”
Maybe the universe is so elegant that there is just enough energy to balance out and stop the universe expanding at some point, also known as a Flat universe. Whatever the ending, you and I will not be here to see it, but it is fabulous to contemplate anyway.