Something Versus Nothing: Can Neutrinos Explain It? — Dare to Know

Most of us have asked ourselves why there is something versus nothing in the universe. Find out how neutrino particles point to the answer.

Like most people of a certain age, most of my introduction to science came, not from the classroom, but Star Trek. The science-fiction mega-franchise offered daring adventures, but it wasn’t the best way to start thinking about science when it came to realism.

For one thing, for reasons that were never satisfactorily explained, there was gravity inside the Enterprise and all other spaceships. Another bizarre irregularity was that all of the aliens they encountered were humanoid and spoke flawless English.

Sometimes they tried to explain this away by mentioning a device, which never appeared, called the universal translator. Other times, when it served the story, the Klingons spoke a language that humans couldn’t understand.

Warp Drive Powered by Matter-Antimatter Engines

The most significant inaccuracy of all was that the Enterprise could travel far faster than light, which is impossible. The writers explained this by inventing something called a warp drive, which was powered by some sort of unexplained matter-antimatter reaction in the ship’s engines.

Despite its logical contradictions, Star Trek did lead me to look into what exactly matter and antimatter are and why they explain why there is something versus nothing. That curiosity has led me to many more exciting, true stories than anything dreamed up by Gene Roddenberry. Truth is stranger than fiction because fiction has to make sense.

The reason I didn’t know much about antimatter is because it barely exists at all. In theory, for every particle of matter, there’s supposed to be a corresponding antiparticle.

For Every Particle of Matter, a Corresponding Antiparticle

For example, antiprotons have the same mass as protons but the opposite charge. Positrons have positive charges, but their mass equals that of electrons, which have negative charges.

When a particle of matter collides with a particle of antimatter, they utterly annihilate each other. This collision releases unimaginable amounts of energy.

That’s the basis of the matter-antimatter reactor on the Enterprise. The writers couldn’t come up with any other way to explain how a ship could have enough energy to travel the incomprehensible distance between star systems.

We’ve Generated Less Than A Nanogram of Antimatter

The mystery of antimatter is that it’s all but impossible to find it anywhere. We can produce it in particle accelerators, but for all their best efforts, scientists have generated less than a nanogram of antimatter in the lab.

The reason this is striking is that at one point, there should have been equal amounts of matter and antimatter in the universe. Within the first second of the big bang, scientists believe that pairs of particles and antiparticles began popping in and out of existence in the hot, dense space-time of the primeval universe.

The law of physics that dictates that there must be an equal number of positively and negatively charged particles is called charged particle symmetry (CP symmetry for short). Since they form in pairs, you would think that those early symmetric particles would all have annihilated each other, leaving a universe of nothing but energy.

There is Hardly Any Antimatter Visible

Yet, here we are, in a universe where everything we are aware of, including us, is made of matter particles. There is hardly any antimatter visible.

It’s part of a question that has probably crossed everyone’s mind at some point. Why is there anything at all, or to put it another way, why is there something versus nothing?

Humans like symmetry, and we see it in patterns everywhere we look, including our bodies. So, it’s troubling that matter and antimatter are so asymmetrical in the universe. Cosmologists call it the matter-antimatter asymmetry problem.

Matter-Antimatter Asymmetry Problem

Last week, a team of researchers called the T2K collaboration published new results in the journal Nature that bring us a step closer to solving this problem. T2K stands for Tokai to Kamioka.

It’s an experiment that transmits a high energy beam of tiny particles called muon neutrinos. They go from Tokai, on Japan’s east coast, over a distance of 295 km to Kamioka in western Japan.

We’ve talked about neutrinos in previous stories. They are tiny particles that carry a neutral charge.

Neutrinos Are Tiny Particles That Carry A Neutral Charge

They have probably one-one millionth of the mass of an electron. Neutrinos are virtually undetectable, and they pass through everything they encounter, usually without affecting it in any way.

It might help to visualize a neutrino if you can conceive of something that is 10 billion, billion, billion times smaller than a grain of sand. Then again, it might not.

What the scientists at T2K discovered is that neutrinos and antineutrinos may not be symmetrical in terms of their oscillation or “flavour.” They did this by sending muon neutrinos and muon antineutrinos through their 295 km beam from a transmitter called J-PARC in Tokai.

Sending Neutrinos and Antineutrinos Through 295 KM Beam

At the other end, the detector in Kamioka only picks up a tiny fraction of the neutrinos or antineutrinos. Another small fraction oscillates, or changes “flavours,” from muon to electron neutrinos or antineutrinos in a predictable way, based on the laws of probability and quantum mechanics.

The number of neutrinos and antineutrinos didn’t oscillate symmetrically. There was an evident bias in favour of neutrinos versus antineutrinos. In other words, they detected a bias toward matter versus antimatter.

Nobody has ever been able to show a violation of CP symmetry in nature before. Silvia Pascoli of Durham University in England and Jessica Turner of the Fermi National Accelerator Laboratory in Batavia, Ill., wrote that T2Ks results were “undeniably exciting.”

“Indication — Origins of Matter-Antimatter Asymmetry”

They went on to say that, “These results could be the first indications of the origin of the matter-antimatter asymmetry in our universe.” The researchers themselves are more circumspect. They’re not about to declare that they’ve explained why there’s something versus nothing.

They write, “While this result shows a strong preference for enhancement of the neutrino rate in T2K, it is not yet clear if CP symmetry is violated or not.” The odds of their results being mere random chance are a thousand to one.

They are steadfastly holding themselves to the usual standard in particle physics. T2K’s goal is to prove this isn’t a fluke with a certainty of a million to one.

Plan to Prove with a Certainty of a Million to One

They explain how they plan to do that like this. “To further improve the experimental sensitivity to a potential CP symmetry violating effect, the T2K Collaboration will upgrade the near detector suite to reduce systematic uncertainties and accumulate more data, and J-PARC will increase the beam intensity by upgrading the accelerator and beamline.”

Every culture has a story that explains why there’s something versus nothing. Our scientific progress has made us comfortable in many tangible ways. Still, it has robbed us of any reassurance about what we’re doing here in the universe.

We need a new, demonstrably true story explaining the origin of matter. Then we can restore our grasp of what Thomas Berry called our “proper role in the great community of existence.”

We always have more to learn if we dare to know.
Learn more:

Tokai to Kamioka Experiment
Constraint on the matter-antimatter symmetry-violating phase in neutrino oscillations
The matter-antimatter asymmetry problem
The 5 Big Questions We Need Cosmology to Answer
My Happy Little Neutrino

Originally published at https://daretoknow.ca on April 27, 2020.