A Wrinkle in Spacetime

On March 9, a movie based on the beloved science fantasy novel A Wrinkle in Time hits the big screen. Although it is a work of fiction, Madeleine L’Engle’s book was inspired by a real scientific principle proposed by renowned physicist Albert Einstein—a theory that researchers recently confirmed.

More than 100 years ago, Einstein suggested that space and time can warp and wrinkle. In the 1940s, L’Engle read a book about Einstein and his theories. She worked his idea about wrinkling spacetime into an interplanetary adventure, which she started writing in 1959. In the story, awkward teenager Meg Murry leads her little brother and a classmate on a quest to rescue her father, a brilliant physicist trapped on a distant planet during a top-secret experiment gone wrong. Einstein’s wrinkles allow the trio of kids to jump through space, visiting other planets without a spacecraft.

On March 9, a new movie hits the big screen. It’s based on the much-loved science-fantasy novel A Wrinkle in Time. Madeleine L’Engle’s book is a work of fiction, but it was inspired by a real scientific idea. The famous physicist Albert Einstein came up with this principle. Now researchers have confirmed it.

Einstein came up with the idea more than 100 years ago. He suggested that space and time can warp and wrinkle. In the 1940s, L’Engle read a book about Einstein and his theories. She worked his idea into a space adventure, which she started writing in 1959. In the story, Meg Murry is an awkward teenager. She leads her little brother and a classmate on a search for her missing father, who’s a brilliant physicist. He got trapped on a distant planet during a top-secret experiment gone wrong. Einstein’s wrinkles allow the three kids to jump through space, visiting other planets without a spacecraft.

L’Engle struggled to get A Wrinkle in Time published. Publishers said its concepts were too complex for young adults—her intended audience—to understand. And some feared readers wouldn’t want a science fiction story with a female protagonist. Dozens of publishing companies rejected the manuscript. But after the book was finally published in 1962, it won the Newbery Medal for children’s literature. It became a runaway success and is considered a classic.

L’Engle was far from the only person intrigued by Einstein’s ideas about spacetime. Scientists have been trying to find ways to confirm or disprove his theory since it was first announced. In the past few years, they finally made some headway. They’ve discovered that our universe truly does ripple and wrinkle the way Einstein predicted.

Last November, three physicists who laid the foundation for detecting these wrinkles, called gravitational waves, received the prestigious Nobel Prize for their work. Scientists believe the groundbreaking discovery offers a radical new way to study the cosmos.

L’Engle struggled to get A Wrinkle in Time published. The book was for young adults. But publishers said its ideas were too hard for teens to understand. And some feared readers wouldn’t want a science-fiction story with a female main character. Dozens of publishing companies turned down the story. But the book was finally published in 1962. It won the Newbery Medal for children’s literature. It became a huge success and is considered a classic.

L’Engle wasn’t the only person interested in Einstein’s ideas about spacetime. Scientists have been trying to support or disprove his theory since he first announced it. In the past few years, they finally made some progress. They’ve found that our universe really does ripple and wrinkle like Einstein said.

Three physicists laid the foundation for finding these wrinkles, called gravitational waves. Last November, they received the famous Nobel Prize for their work. Scientists are excited about the groundbreaking discovery. They say it offers a new way to study the cosmos.

In 1915, Einstein published his theory of general relativity. It stated that three-dimensional space is connected to a fourth dimension: time. Einstein described this concept, known as spacetime. He proposed that the presence of matter and energy causes spacetime to curve. That curvature creates gravity, the force that attracts objects to one another (see Warped Space).

General relativity predicts that in some areas of spacetime, called black holes, gravity is so strong that even light can’t escape. Einstein’s theory suggests that explosions and violent collisions in space, like one between two black holes, send gravitational waves through spacetime, much like the way a dropped pebble sends ripples across a pond. These waves “change the shape of spacetime itself, which stretches and shrinks as they move,” says Marco Cavaglià, an astrophysicist at the University of Mississippi.

Einstein published his theory of general relativity in 1915. Space has three dimensions. The theory said that space is connected to a fourth dimension: time. This idea is known as spacetime. Einstein suggested that the presence of matter and energy makes spacetime curve. This creates gravity, the force that attracts objects to one another (see Warped Space).

Einstein’s theory predicts that some areas of spacetime have very strong gravity. Even light can’t escape. These areas are called black holes. Einstein’s theory says that giant collisions, like a crash between two black holes, send gravitational waves through spacetime. This is similar to a dropped pebble sending ripples across a pond. Einstein’s waves “change the shape of spacetime itself, which stretches and shrinks as they move,” says Marco Cavaglià. He’s an astrophysicist at the University of Mississippi.

Einstein’s idea of gravitational waves inspired the title and storyline of L’Engle’s book. The children in the novel travel across wrinkles in spacetime. A character named Mrs. Whatsit uses an analogy of a traveling insect to explain the process. She says a bug would take a long time to walk across her skirt. But if she were to fold the fabric—similar to how gravitational waves bend spacetime—she could bring two distant sections closer together. The insect could then walk over the fold and take a shortcut from one side of her skirt to the other.

The title and storyline of L’Engle’s book came from Einstein’s idea of gravitational waves. The children in the novel travel across wrinkles in spacetime. A character named Mrs. Whatsit uses an insect to explain this. She says a bug would take a long time to walk across her skirt. But if she were to fold the skirt, she could bring two distant parts close together. The folding is similar to how gravitational waves bend spacetime. The insect could walk over the fold and take a shortcut across her skirt.

Einstein thought that wrinkles in spacetime would be too small to detect. But as technology advanced, scientists took on the challenge. In the 1960s, they hatched a plan to use concentrated light from lasers to measure changes in spacetime as gravitational waves pass through it. In the 1990s, construction began on a giant pair of instruments called the Laser Interferometer Gravitational-Wave Observatory (LIGO) to accomplish the feat (see How LIGO Works).

Einstein thought that wrinkles in spacetime would be too small to find. But technology got better, and scientists took on the challenge. In the 1960s, they came up with a plan. They decided to use beams of laser light to measure changes in spacetime as gravitational waves pass through it. In the 1990s, they started building a giant pair of instruments called the Laser Interferometer Gravitational-Wave Observatory (LIGO) (see How LIGO Works).

To detect gravitational waves, LIGO has to sense a shift equivalent to a hair’s-width change in the distance between the sun and its nearest neighboring star. “It’s the most precise measurement device humans have ever built,” says Cavaglià, who is a member of the LIGO collaboration.

LIGO launched its hunt for Einstein’s ripples in 2002. By 2010, the search had come up empty. But researchers didn’t give up. They rebuilt the detectors to make them 10 times more sensitive. Days after scientists switched on LIGO’s new detectors in 2015, the first gravitational waves directly measured on Earth rocked the sensors. And they matched the pattern for a collision between two black holes predicted by Einstein’s theory. “When we saw these signals, it was amazing and almost a little scary,” says Cavaglià. “We realized this was something big—a perfect signal.” Since then, they’ve detected five more black hole collisions and a crash between two neutron stars, which form when giant stars explode and collapse.

To find gravitational waves, LIGO has to sense a very small change in distance. It’s like detecting a change as small as a hair’s width between the sun and the next closest star. LIGO is “the most precise measurement device humans have ever built,” says Cavaglià, a member of the LIGO team.

LIGO began hunting for Einstein’s ripples in 2002. By 2010, the search had found nothing. But researchers didn’t give up. They made the detectors 10 times more sensitive. Scientists turned on LIGO’s new detectors in 2015. Days later, the sensors picked up the first gravitational waves directly measured on Earth. Einstein’s theory predicted a pattern for a collision between two black holes. The waves LIGO detected matched the pattern exactly. “When we saw these signals, it was amazing and almost a little scary,” says Cavaglià. “We realized this was something big—a perfect signal.” Since then, they’ve detected five more black hole collisions and a crash between two neutron stars. These objects form when giant stars explode and collapse.

Many scientists believe the biggest discoveries are yet to come. “Almost everything we know about the universe up to now comes from studying light,” says Nergis Mavalvala, a LIGO member and physicist at the Massachusetts Institute of Technology. But some objects, like black holes, don’t emit light. “Gravitational waves open up a new way to observe,” she says.

Along with studying black holes, scientists could peer back into the early days of the universe after its explosive birth during the big bang. When the universe was young, it was so hot and dense that light couldn’t travel through it. But gravitational waves streamed freely through spacetime. Their imprint may linger today, the way lines remain on a sandy beach after waves hit the shore. For events that emit light, like a neutron star collision, gravitational waves provide a rich new stream of information. “It’s like transitioning from silent movies to movies with sound,” says Cavaglià.

Many scientists believe the biggest discoveries are still ahead. “Almost everything we know about the universe up to now comes from studying light,” says Nergis Mavalvala. She’s a LIGO member and a physicist at the Massachusetts Institute of Technology. But some objects, like black holes, don’t give off light. “Gravitational waves open up a new way to observe,” says Mavalvala.

Besides studying black holes, scientists could look back at the early universe. After its start during the big bang, the universe was hot and dense. Light couldn’t travel through it. But gravitational waves flowed freely through spacetime. Their imprint may still be there, the way lines stay on a sandy beach after waves hit the shore. Events like a neutron star collision give off light. But gravitational waves provide a new kind of information about them. “It’s like transitioning from silent movies to movies with sound,” says Cavaglià.

Does the discovery of gravitational waves mean it’s possible to leap through space and time, like in L’Engle’s novel? For now, no one knows. The waves might help researchers hunt for evidence of wormholes, says Mavalvala. Scientists have theorized the existence of these severely warped areas of space, which could represent shortcuts across the universe.

“We don’t even know what such a thing would look like,” she says, “but if we someday detected weird gravitational signals, it would be beyond exciting to think about.”

The characters in L’Engle’s novel leaped through space and time. Does the discovery of gravitational waves mean this is possible? For now, no one knows. Gravitational waves might help researchers hunt for signs of wormholes, says Mavalvala. Scientists have wondered if these severely warped areas of space exist. They could be shortcuts to distant parts of the universe. “We don’t even know what such a thing would look like,” she says, “but if we someday detected weird gravitational signals, it would be beyond exciting to think about.”