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Dark matter and dark energy frighten me and fascinate me.

In astronomy and cosmology, dark matter is a type of matter that is hypothesized to account for a large part of the total mass in the universe.

I find different numbers online, but from the Planck mission team comes the percentages that the total mass–energy of the universe contains 4.9% ordinary matter, 26.8% dark matter and 68.3% dark energy. That means that 84.5% of the total matter in the universe is dark matter.

We can’t see dark matter with our telescopes because it doesn’t seem to emit or absorb light or other electromagnetic radiation at any significant level.

So, how can we even hypothesize that it exists? Scientists infer its existence from its gravitational effects on visible matter and from radiation. It is the kind of research physicists do using instruments like the Large Hadron Collider in Switzerland.

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If you’re not a science reader, you can get a pretty technical but intelligible overview of dark matter and dark energy from Wikipedia. But I have to admit that my interest in the topic was piqued by references to it in fiction, movies and TV.

It pops up in all kinds of places. Dark matter fuels the starship in the comedy cartoon series Futurama. In the iterations iterations of Star Trek, it frequently was mentioned. In Next Generation and Deep Space Nine, the Enterprise encounters a dark matter nebula. Back in 1995, an episode of one of my favorite shows, The X-Files (“Soft Light”) a scientist exposed to dark matter is transformed so that his shadow destroys the molecules of anything it touches and converts it into a puddle of pure energy.

The books that really got me thinking about it were the His Dark Materials (The Golden Compass/ The Subtle Knife/ The Amber Spyglass) trilogy by Philip Pullman. His heroine, Lyra, is an orphan living in a parallel universe in which science, theology, and magic are entwined. In that world, dark matter is called “Dust. ” Dust/dark matter was more of a form of consciousness. It keeps our multiple worlds linked. It allows for precognition. That is covered in the first book in the trilogy The Golden Compass (I was disappointed with the the movie version – even though it had Nicole Kidman.) Interestingly, for a series that is quite anti-religion, dust is the matter of which angels are made.

Isn’t it fascinating to think that most of the universe we live in is not what we observe? It’s not the things we can touch but what is between the things we touch. It is hardly new or original to think that there is more than the eye can see, but that is what dark matter suggests.

It has been suggested that dark energy is one of the “failures” of general relativity. Apologies to Albert Einstein for that. More theories on dark energy have come from string theory, brane cosmology and the holographic principle. Just theories. Relativity and topics such as quintessence and the cosmological constant are beyond the scope of this blog.

Recently, I have been reading about research into WIMPs, weakly interacting massive particles. (Dark matter and energy is a more interesting term than WIMP.) These are also theoretical, and they almost never interact with normal matter. They may be another clue to the fundamental origin of matter and antimatter. Maybe it is no coincidence that the number of protons and neutrons in the universe is roughly equivalent to the number of WIMPs.

There is still much uncertainty and mystery about the nature of dark matter and of our universe. That’s good. I am glad we are still searching and sometimes finding answers. I think that is what was intended.

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