A deeply disturbing and controversial line of thinking has emerged within the physics community.

It’s the idea that we are reaching the absolute limit of what we can understand about the world around us through science.

“The next few years may tell us whether we’ll be able to continue to increase our understanding of nature or whether maybe, for the first time in the history of science, we could be facing questions that we cannot answer,” Harry Cliff, a particle physicist at the European Organization for Nuclear Research — better known as CERN — said during a recent TED talk in Geneva, Switzerland.

Equally frightening is the reason for this approaching limit, which Cliff says is because “the laws of physics forbid it.”

At the core of Cliff’s argument are what he calls the two most dangerous numbers in the universe. These numbers are responsible for all the matter, structure, and life that we witness across the cosmos.

And if these two numbers were even slightly different, says Cliff, the universe would be an empty, lifeless place.

Dangerous No. 1: The strength of the Higgs field

The first dangerous number on Cliff’s list is a value that represents the strength of what physicists call the Higgs field, an invisible energy field not entirely unlike other magnetic fields that permeates the cosmos.

As particles swim through the Higgs field, they gain mass to eventually become the protons, neutrons, and electrons comprising all of the atoms that make up you, me, and everything we see around us.

Without it, we wouldn’t be here.

We know with near certainty that the Higgs field exists because of a groundbreaking discovery in 2012, when CERN physicists detected a new elementary particle called the Higgs boson. According to theory, you can’t have a Higgs boson without a Higgs field.

But there’s something mysterious about the Higgs field that continues to perturb physicists like Cliff.

According to Einstein’s theory of general relativity and the theory of quantum mechanics — the two theories in physics that drive our understanding of the cosmos on incredibly large and extremely small scales — the Higgs field should be performing one of two tasks, says Cliff.

Either it should be turned off, meaning it would have a strength value of zero and wouldn’t be working to give particles mass, or it should be turned on, and, as the theory goes, this “on value” is “absolutely enormous,” Cliff says. But neither of those two scenarios are what physicists observe.

“In reality, the Higgs field is just slightly on,” says Cliff. “It’s not zero, but it’s ten-thousand-trillion times weaker than it’s fully on value — a bit like a light switch that got stuck just before the ‘off’ position. And this value is crucial. If it were a tiny bit different, then there would be no physical structure in the universe.”

Why the strength of the Higgs field is so ridiculously weak defies understanding. Physicists hope to find an answer to this question by detecting brand-new particles at the newly upgraded particle accelerator at CERN. So far, though, they’re still hunting.

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