Dark matters

This is a bit weird. A few days ago, I drove to my local hospital for an MRI scan. I listened to a programme on the radio about dark matter and dark energy. You know the sort of light hearted programme to while’s away your time that you half listen to?

So I arrived at the Neurosciences clinic, changed and was directed to the beast of a machine. I was getting a head and neck scan, which for me, involved first verifying that I have no metal in my head or about my person (that could be disastrous ), then laying on a platform and having your neck and head held in a fixed position.

Next, a tube is inserted into your arm and dark cloudy liquid is piped into your bloodstream. After a few minutes the platform slides you into the enclosed space (I’m guessing one to two inches of space around your head, and you lay there, very still, for about 30 minutes, while something spins around your head making very loud rhythmic noises, bangs and squeals. Sort of like you might imagine a Star Trek scanner to be, if it was used in a horror film.

You are given a little squeezy thing, if it becomes too much, you clench your hand around it, they slide you ought frowning and the whole process has to be restarted.

I can’t say I am a big fan of enclosed spaces. Or the deafening noises that the machine produces. So to distract myself, I pondered the subject of dark matter. As you do.

It seems that they are two concepts that physicists have invented to explain what they have observed in the universe.

Firstly, planets revolve around their suns, solar systems revolve around a centre of a galaxy and they aren’t flung away into empty space. Einstein’s general theories explain why this happens (gravity warps space so the planets and solar systems are rolling around the sloped surface of space) but there is a problem. The density of suns and the galaxies isn’t enough to create such a steep slope. Therefore there is something else, something heavier, warping the space. And this something else is about ten times heavier than anything that we can see. Dark matter. It isn’t a single thing as such, it may be many things that we just cannot observe under normal conditions. But it is all around us.

Some enterprising scientists are conducting experiments miles underground, in deep abandoned mine shafts, trying to detect it.

The second concept is all about the expansion of the known universe. Everyone expected it to be slowing, when the opposite is true. Again, to make sense of this, the concept of dark energy was created. Some invisible force that is literally pushing galaxies apart. And the further apart they are, the more space for dark energy, the harder the push is.

When I got home, I watched numerous videos online, read articles, and pondered.

Dark matter must make up around 25% of the rest due to it’s gravitational effect on the rotation of planets around stars and solar systems around the centres of galaxies. Dark energy has to occupy, based on calculations, around 70% of the known universe.

The conclusion is this. I (and you if you have read and digested this) know as much about dark matter and dark energy as our most eminent scientists. And the stuff we do know about, makes up less than 5% of everything.

And as the saying goes, “you don’t know what you don’t know!”.

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Get real

I considered several different themes for today’s entry. Perhaps something relevant to the time of year like “Remember, Remember the 5th of November” but as neither my wife nor I  felt like braving out in the cold to watch a display, that was off the cards.

Or perhaps something topical like the current US elections, and how the two party system is funded by special interest lobby groups who seem to wield far too much power, not just in the US, but here in old blighty too.

Or how all that pales into insignificance in the wake of Sandy and the poor buggers who are left with no electricity or heating as the temperature plummets.

Eventually though, I decided I wouldn’t write about any of those things. Today is a none entry. It doesn’t exist. What you see before you is a figment of your over active imagination. You may think it exists. You may even be able to drag your mouse across the words and see it being highlighted in blue an imaginary selection. But that doesn’t mean anything. The only place this post exists is in your mind’s eye. Magnetic charges on a disk platter. Pulses of light along a string of fibres. Electrical impulses firing and exploding against a slice of glass. Pulsing through your synapses inside your head.

Now ask yourself this. If this doesn’t exist, what else might not be real. Perhaps you are loosing your grip on reality.

But what is reality anyway?