Young as he still is at 34, Professor Nima Arkani-Hamed was far younger when he walked into a high-school classroom and found proof that the universe was, indeed, expanding.
He was in Grade 8 at Zion Heights Junior High School in northern Toronto, and the classroom belonged to Charles Ledger, a teacher who had developed his own brand of supercharged math instruction for high-performing students ready to go beyond their textbooks.
Of course, Dr. Arkani-Hamed could not have predicted the precise sequence that would land him where he is today: at the utter limit of humanity's understanding of the universe, as one of the world's top particle theorists, with a fully tenured teaching post at Harvard to boot.
Instead, he focused on what was in front of him -- interesting problems and drills, drills, drills -- and suddenly, his world got bigger.
"It was an amazing atmosphere that wasn't replicated for me until well into my college years," Dr. Arkani-Hamed said this week, seated beside his former teacher, now 74, after they reunited in a high-school classroom in Waterloo, Ont.
"At a very truly fundamental level, it started me off in the sort of frame of mind that I keep and carry with me today."
Moments later, that frame of mind opened up for a crowd in the Waterloo Collegiate auditorium when the long-haired physicist, in his black pants and black untucked shirt, took the stage to deliver a mind-bending public lecture called The Future of Fundamental Physics.
"I realize this is a rather modest title," Dr. Arkani-Hamed said to laughs from an audience dotted with scientists from Waterloo's Perimeter Institute for Theoretical Physics, which played host to the event and arranged to bring Mr. Ledger and his family to it from the Toronto area.
While the former teacher beamed from the front row -- reflecting, perhaps, on the math competitions Dr. Arkani-Hamed helped his school to win, or the dense Russian math book he and a classmate excitedly brought in to school after finding it at the Canadian National Exhibition -- the professor explained how the scientific community is on the brink of "a real revolution in the understanding of physics."
The catalyst for that potential revolution lies in what will be the largest experiment in human history, in a vast cavern built beneath the French-Swiss border, where a mammoth contraption called the Large Hadron Collider is expected to power up this fall.
Through a circular tunnel with a 27-kilometre circumference, scientists will send protons (smaller than atoms, invisible to the eye) hurtling in opposite directions at insanely high speeds, because "when they smash into each other, something interesting happens," Dr. Arkani-Hamed said.
From that "something," experts hope to divine answers to questions that have lingered since the last major step forward in physics, in the 1970s, when the so-called Standard Model was developed to explain how particles of matter interact.
The Standard Model explains all the physical forces except gravity, which is by far weaker than all the others. The new collider, the most powerful ever built, could help researchers find out why.
More specifically tantalizing to Dr. Arkani-Hamed is the potential for it to reveal what he and a group of like-minded mavericks have come to suppose: that our vast universe might be but one of billions, each governed by its own physical laws.
"Our entire universe could be this tiny, minuscule speck of nothing in this giant multiverse," he said, underscoring both the insignificance and the wonder of human reality, given the delicacy of the balance of forces that underpin it.
"Everywhere else in the multiverse is lethal; a few places allow us to exist," he said, adding that a "big crunch," or collision, could one day spell our doom.
