The hunt is on for a dark force of nature

Getting dark: Scientists believe that dark matter will be found at the edges of galaxies. © NASA

Is the search worth it? Scientists are launching an experiment to find a mysterious fifth force of nature. If they find it, it will give us an insight into the unseen world of dark matter.

At a lab near Rome, scientists have begun a search for a mysterious “dark force” of nature. It might sound a bit like Star Wars — the experiment is even named Padme — but this is no science fiction. In fact, they are searching for an answer to one of the biggest questions of the universe: what is in it?

“At the moment, we don’t know what more than 90% of the universe is made of,” researcher Mauro Raggi explained to The Guardian. Everything that we can see, from the stars to your shoes, adds up to just 4%.

Most scientists believe that the rest is a “dark world” of dark matter and dark energy. It does not interact with anything that we can see and touch. As a result, very little is known about it.

Padme will search for a “dark force” that links that invisible world with our own.

At the moment, we know about four fundamental forces of nature. There is gravity, which keeps your feet on the ground. Electromagnetism interacts with light and electricity. Strong force keeps atoms together, and weak force is involved in radiation.

If it exists, this fifth force will be the dark equivalent of electromagnetism. But the chances of finding it are slim. “We are shooting in the dark in every sense,” said Raggi. “But if you are shooting, you at least have a chance.”

Is it really worth all the effort?

May the force be with you

It is pointless, say some. Why spend all this time looking for something we cannot see, cannot use, and have little hope of finding anyway? Some scientists are sceptical that dark matter even exists — what a waste of effort.

Of course it is worth it, argue others. The potential for discovery is huge. Think of everything that happened after we found the forces of gravity and electricity. A dark force would be just as important. Let’s hope we find it.

You Decide

  1. Do you think that a dark force exists?

Activities

  1. Dark matter is more famous for what we don’t know about it than the things we do know. Write a list of questions you would want to answer if you were a scientist.

Some People Say...

“The most beautiful thing we can experience is the mysterious. It is the source of all true art and science.”

Albert Einstein

What do you think?

Q & A

What do we know?
When scientists observe galaxies, they come to an alarming conclusion: there is not enough stuff there for gravity to hold them together. This means that there must be something else there that we cannot see. Scientists call this extra stuff dark matter.
What do we not know?
What it is, how it works, where it comes from, or anything else about it. We are not even 100% sure that it exists.

Word Watch

Lab
The National Institute for Nuclear Physics.
Padme
The name has nothing to do with Luke Skywalker’s mother; it stands for Positron Annihilation into Dark Matter Experiment.
Dark matter
This is thought to make up roughly a quarter of the universe, and to be related to galaxies.
Dark energy
This is thought to make up around 68% of the universe, and to be related to its expansion.