Rich Isaacson, seen in his backyard in Pentagon City, Va., wrote his thesis on gravitational waves and says he always thought their existence would be proven sometime during his career. But he didn't realize that trying to see them would become his career. Ryan Kellman/NPR hide caption
Imagine spending 40 years and more than a billion dollars on a gamble.
That's what one U.S. government science agency did. It's now paying off big-time, with new discoveries about black holes and exotic neutron stars coming almost every week.
And while three physicists shared the Nobel Prize for the work that made this possible, one of them says the real hero is a former National Science Foundation staffer named Rich Isaacson, who saw a chance to cultivate some stunning research and grabbed it.
"The thing that Rich Isaacson did was such a miracle," says Rainer Weiss, a physicist at MIT and one of the 2017 Nobel laureates. "I think he's the hero. He's a singular hero. We just don't have a good way of recognizing people like that. Rich was in a singular place fighting a singular war that nobody else could have fought."
Without him, Weiss says, "we would've been killed dead on virtually every topic." He and his fellow laureate Kip Thorne recently donated money to create a brand new American Physical Society award in Isaacson's honor.
This unlikely story begins back in the 1960s, when Isaacson was a doctoral student and got interested in one of Albert Einstein's predictions.
In 1916, Einstein theorized that any time two massive objects crash together, shockwaves should move through the very fabric of the universe. These gravitational waves through space and time are like the ripples you see in water when you toss in a pebble.
"For my thesis, I showed how gravitational waves behave like other kinds of waves, like light and radar, X-rays," Isaacson says.
His calculations showed that these waves weren't just some mathematical obscurity, but something that conceivably could be measured. "It showed exactly how Einstein's theory worked in detail in making gravitational waves," Weiss says. "And it was done in such a way that it was mathematically correct and nobody could dispute it anymore."
Einstein, who'd gone back and forth on the question of gravitational waves, thought that they'd most likely never be detected — the distortions they create in space are just too tiny.
Isaacson was more optimistic. "I imagined that sometime in my career, we would see it," he says.
He just didn't realize that trying to see it would become his career.
Back in the early 1970s, Isaacson took a job at the fledgling National Science Foundation, working to review funding proposals. And Weiss wanted money for a crazy idea he was pursuing: trying to detect gravitational waves using lasers.
Lasers could, in theory, be used to measure very, very small distortions in space — like changes that were a thousandth of the width of an atomic nucleus. "Most people said, 'Holy mackerel! He must be nuts. You can't do that,' " Weiss recalls.
The technology was just too hard. Plus, no one even knew what in the universe could spew out gravitational waves strong enough to be measured like that.
Normally, says Weiss, "with those two things ... that proposal would have been dead on arrival. But it wasn't that way with Rich."
Because Isaacson had studied gravitational waves, he saw the potential. So he personally shepherded this research for almost three decades.
It became the biggest project the National Science Foundation had ever funded.
"He sat in the NSF and singlehandedly — I mean singlehandedly — convinced everybody in the NSF this was the right thing for the NSF to support and the science was going to be spectacular if it should succeed," says Weiss. "And he made the argument stick."
He made it stick through years of prototype tests and expert-review panels and feasibility studies and management nightmares. Lots of people worked on this project, of course, but Weiss says that "the elegance of Rich was the fact that he knew how the system worked and he knew the science."
"He was an advocate, like a messiah, for this whole idea of detecting gravitational waves. And then he became more of a strategist for it," Weiss explains. "Now imagine the guy running the program in the NSF becoming the major advocate for it and also the guy who did most of the strategizing for it. To me, that was a miracle. And it is the thing that made it so that the field survived."
After all, plenty of people thought it was insane to spend hundreds of millions of dollars to build giant detectors that might never detect anything — especially astronomers, who worried that the money would get diverted from sure-bets such as building new telescopes.
"There's always a danger that the project can get stopped," Isaacson says. "And like all of the big projects in science, it's a roller-coaster ride."
Officially, Isaacson never worked on this more than about half-time. In reality, it was all-consuming. The long work days took a toll. At one point, his blood pressure went sky high and his doctor became alarmed.
Isaacson says he feels lucky to have been in a position to try to change history. "But history demands you pay a price for that privilege, in terms of all the stress and agony and lifestyle and family events," he says. "If you're willing to pay the price, OK, you've got this chance and you can go ahead and maybe it will work. Maybe it won't."
In 2002, Isaacson retired. That was also the year the NSF started searching the sky with its brand-new Laser Interferometer Gravitational-Wave Observatory (LIGO): two massive detectors, one in Washington state and one in Louisiana. Each has lasers that travel down pipes 2 1/2 miles long.
For years, these detectors hunted for gravitational waves ... and found nothing.
Scientists stuck with it. They improved the detectors' instruments. And in 2015, Isaacson traveled to Maine for a getaway with Weiss and another colleague, who opened up a laptop to reveal measurements that were made just a couple days before.
It was the first-ever detection of gravitational waves, from two black holes that collided over a billion light-years away. "It was absolutely clear that this fantastic thing had just happened," Isaacson recalls.
The realization produced "a little warm glow," he says. "I guess now that I'm a few years away from it, I'm beginning to feel it more."
Asked about the chances that a government-funded science project like this could happen today, he says: "Zero."
"We live in a very different time," Isaacson says. "Nobody can, I think, take such large-scale, high-risk, long-term research."
Gravitational wave science has given astronomers an unprecedented ability to see some of the most powerful and exotic events in the universe. In 2017, for example, the LIGO detectors registered a collision between two neutron stars, and telescopes were then able to find the cosmic fireworks and watch them in real time.
Just last month, researchers started up the massive detectors after another major hardware upgrade. They've already detected at least five more gravitational wave events.
Isaacson keeps an eye on the science, but in retirement he's finally free to fully pursue another love: antique textiles from Central Asia. He's even written a book on the decorated bands that wrap around nomadic tents.
He likes carpets and weavings with geometric designs. "Since modern physics is highly geometrical, it's not all that different," Isaacson says. "Except that physicists work in somewhere between four or 10 dimensions, usually. So for a retirement career, working in two dimensions is a piece of cake."
He unrolls a red carpet made by an Uzbek tribe in the mid-19th century, and says the forgotten artisans who made work like this, usually women, were a hundred years ahead of famous modern art celebrities.
"They were anonymous," Isaacson says, "and they were completely ignored. But they were doing beautiful things."
https://www.npr.org/2019/05/19/723326933/billion-dollar-gamble-how-a-singular-hero-helped-start-a-new-field-in-physics
2019-05-19 12:25:00Z
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