Science keeps proving Einstein is still right—but what are we missing?
9/30/2020 9:09:10 AM
New popular science book gives the public an insider's view of some of the most advanced scientific experiments of our times
How do we know black holes exist? What would it sound like if humans could hear a gravitational wave as it stretches and contracts the fabric of spacetime? And how does GPS rely on general relativity?
The most advanced large-scale scientific experiments of the last century consistently demonstrate the remarkable staying power of Albert Einstein’s theory of general relativity. But what future experiments will it take to be able to harmonize the strange physics of quantum mechanics with general relativity?
On October 1, 2020, a new popular science book, Is Einstein Still Right? Black Holes, Gravitational Waves, and the Quest to Verify Einstein’s Greatest Creation, published by Oxford University Press, will hit bookshelves across the U.S.
Illinois Physics Professor Nicolas Yunes teamed up with University of Florida Distinguished Professor of Physics Clifford Will to write this follow up to Will’s 1986 bestseller, Was Einstein Right? Putting General Relativity to the Test. In the new book, the authors bring readers up to date on some of the biggest scientific questions of our times—and what fundamental scientific research can teach us about the nature of the universe, from gravitational waves, to black holes, dark matter, and dark energy.
Many people may first have learned about the existence of gravitational waves in February 2016 when the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced it had successfully detected them, but Einstein had already predicted these ripples in the fabric of spacetime 100 years prior. LIGO's initial observation became the most recent major test of general relativity, adding to the already overwhelming scientific evidence in support of Einstein’s theory.
In Is Einstein Still Right? Will and Yunes make accessible the history of these tests and the scientists who conducted them, providing analogies and simple line drawings to explain the science. They also explain other experiments readers may have heard about in the news in recent years, including the Event Horizon Telescope (EHT) Collaboration, which captured the first-ever image of a black hole in 2019.
Yunes, who directs the Illinois Center for Advanced Studies of the Universe on the Urbana campus, says, “We tried to bring to life the history and the characters involved in these groundbreaking discoveries, while at the same time providing readers with in-depth scientific explanations without the use of equations.
Will adds, “We wanted to make the science accessible, but we also included real experimental figures, like the actual gravitational wave signal that the two LIGO detectors picked up. There is some minor filtering, but it's almost raw data. You can see the gravitational wave coming, growing, and then dying off. The reader can trace it wiggle by wiggle and see why scientists were able to say, ‘This signal was a gravitational wave.’”
Readers familiar with Will’s earlier book will recognize some of the key players from the history of gravitational wave science, such as Antony Hewish and Jocelyn Bell-Burnell, who first discovered pulsars—rapidly spinning neutron stars that emit regular pulses of radio waves—as well as Joe Taylor and Russell Hulse, who detected the first binary pulsar system. In Is Einstein Still Right?, the authors take a fresh look at those discoveries and include new information that has come to light in recent years.
The latter third of the book brings readers into the twenty-first century with current ground-based gravitational wave detectors and looks forward to the next phase of experimentation with the Laser Interferometer Space Antenna (LISA), a space-based detector scheduled to launch in 2034.
“We describe what is in the works and what kinds of questions scientists will be asking in the coming decades,” notes Yunes. “For scientists who have spent their careers studying general relativity, the past five years have been especially rewarding, but that’s not the only reason the timing felt right to publish a book on Einstein’s theory. Scientists have a responsibility to show the scientific method in action and to demonstrate how we distinguish a scientific fact from other sets of beliefs that we operate under.
“We keep asking if Einstein was right, not because we think he was wrong, but because that’s what physicists do. Even though general relativity has passed every test we have devised, we have to continue searching for deviations from Einstein’s predictions. We know Einstein’s theory cannot be the final word, since it remains incompatible with quantum mechanics. So, we must be missing something. Newton appeared to be right for hundreds of years before observations of Mercury suggested something was amiss. And then Einstein came along.”