Stephen Hawking’s last collaborator on the physicist’s final theory

When Thomas Hertog was first called into Stephen Hawking’s office in the late 1990s, there was an immediate connection between the young Belgian researcher and the legendary British theoretical physicist.

“Something clicked between us,” said Hertog.

That connection would continue even as Hawking’s debilitating disease ALS robbed him of his last ways to communicate, allowing the pair to complete a new theory intended to turn science’s view of the universe on its head.

The theory, which would be Hawking’s last before his death in 2018, was set out in full for the first time in Hertog’s book On the Origin of Time, which was published in the UK last month.

In an interview with AFP, the cosmologist talked about their 20-year collaboration, how they communicated via facial expressions, and why Hawking ultimately decided to write his landmark book A Brief History of Time in the wrong perspective.

‘Designer’ universe

During their first meeting at Cambridge University in 1998, Hawking wastes no time in broaching the problem that is bothering him.

“The universe we observe seems designed,” Hawking told Hertog, communicating via a clicker connected to a speech machine.

Hertog explained that “the laws of physics—the rules on which the universe operates—turn out to be absolutely perfect for the universe to be habitable, and for life to be possible.”

This wonderful chain of good luck extends from the delicate balance that makes it possible for atoms to form the molecules necessary for chemistry to the expansion of the universe itself, which allows for vast cosmic structures such as galaxies.

One “modern” solution to this problem, Hertog said, is the multiverse, an idea that has recently become popular in the film industry.

This theory explains the seemingly designed nature of the universe by making it one of countless other things — most of which are “nonsense, lifeless, sterile,” the 47-year-old added.

But Hawking recognized the “great morass of contradictions into which the multiverse was leading us,” arguing that there must be a better explanation, Hertog said.

outside perspective

A few years into their collaboration, Hertog said, “it began to sink in” that they were both missing something essential.

Hertog said the multiverse and even “A Brief History of Time” were “attempts to describe the creation and evolution of our universe from what Steffen calls a ‘God’s eye perspective'”.

But because we are “inside the universe” and not looking from the outside in, he added, our theories cannot be separated from our perspective.

This is why (Hawking) said that the book “A Brief History of Time” is written from the wrong perspective. ”

Over the next fifteen years, the pair used the oddities of quantum theory to develop a new theory of physics and cosmology from an “observer’s perspective”.

But by 2008, Hawking had lost the ability to use his clicker, and he became increasingly cut off from the world.

“I thought it was over,” Hertog said.

The couple then developed a “somewhat magical” level of nonverbal communication that allowed them to continue working, he said.

Positioned in front of Hawking, Hertog would ask questions and look the physicist in the eye.

He said, “He had a very wide range of facial expressions, ranging from extreme disagreement to extreme excitement.”

It’s “impossible to separate” which parts of the final theory came from himself or Hawking, Hertog said, adding that many ideas had been developed between the pair over the years.

“One big evolutionary process”

Their theory focuses on what happened in the first moments after the Big Bang.

Instead of an explosion that followed a set of pre-existing rules, they suggested that the laws of physics evolved along with the universe.

This means that if you go back far enough, Hertog said, “the laws of physics themselves begin to simplify and disappear.”

“In the end, even after time it evaporates.”

Under this theory, the laws of physics and time itself evolved in a way similar to biological evolution—the title of Hertog’s book is a reference to Darwin’s “On the Origin of Species.”

“What we’re basically saying is that (biology and physics) are two levels of one big evolutionary process,” Hertog said.

He admitted that this theory is difficult to prove because the early years of the universe remain “hidden in the haze of the Big Bang”.

One way to lift that veil, he said, could be by studying gravitational waves, ripples in the fabric of space-time, while another could be via quantum holograms created on quantum computers.