Thirteen million hits resulted from a 16 February Google News search on the term "gravitational waves." An entirely unscientific sampling of a few dozen of them, mostly from prominent publications, also suggests what that total implies: The world is plenty interested in the physics advance that was recent months, reported in Physical Review Letters, and announced on 11 February.
In the 12 February New York Times, the opening paragraphs of the lead article—top right, front page—summarized:
A team of scientists announced … that they had heard and recorded the sound of two black holes colliding a billion light-years away, a fleeting chirp that fulfilled the last prediction of Einstein's general theory of relativity.
That faint rising tone, physicists say, is the first direct evidence of gravitational waves, the ripples in the fabric of space-time that Einstein predicted a century ago. (Listen to it here.) It completes his vision of a universe in which space and time are interwoven and dynamic, able to stretch, shrink and jiggle. And it is a ringing confirmation of the nature of black holes, the bottomless gravitational pits from which not even light can escape, which were the most foreboding (and unwelcome) part of his theory.
More generally, it means that a century of innovation, testing, questioning and plain hard work after Einstein imagined it on paper, scientists have finally tapped into the deepest register of physical reality, where the weirdest and wildest implications of Einstein's universe become manifest.
Conveyed by these gravitational waves, power 50 times greater than the output of all the stars in the universe combined vibrated a pair of L-shaped antennas in Washington State and Louisiana known as LIGO on Sept. 14.
If replicated by future experiments, that simple chirp, which rose to the note of middle C before abruptly stopping, seems destined to take its place among the great sound bites of science, ranking with Alexander Graham Bell's "Mr. Watson—come here" and Sputnik's first beeps from orbit.
The news also appeared on the Washington Post's front page, illustrated by a photograph of Caltech physicist Kip Thorne in front of a depiction of the converging black holes. Thorne worked for decades on the Laser Interferometer Gravitational-Wave Observatory (LIGO) project with his Caltech colleague Ronald Drever, who is now retired, and with MIT's Rainer Weiss and, more recently, with many hundreds of others. On the Wall Street Journal's front page, a pair of teaser blurbs and a depiction of the converging black holes alerted readers to an article inside the A section.
Much of the response has been outright celebratory. In a letter to the New York Times, New York University emeritus physics professor Benjamin Bederson reported "great pleasure" in having read the Times's prominently positioned article. He declared that "Albert Einstein and his 1,000 contemporary co-conspirators" had for the moment "usurped that coveted position" in the news "away from the presidential candidates and various Mideast wars." He added, "At least for one day our pitiable earthly problems had to yield to the monumental collisions of higher powers." He concluded, "God bless Einstein, the world of science and your wonderful science writer, Dennis Overbye, for placing our local woes in their proper perspective."
Prominent science-popularizing physicists sought to elucidate that perspective in Times and Wall Street Journal op-eds. Michio Kaku in the WSJ ended by declaring the opening of "the door to answering the most important philosophical questions of all time, including the creation of the universe." In the Times, Lawrence M. Krauss—a much-discussed source of those rumors preceding LIGO's announcement—ended by speculating that "we may learn more about the beginning of the universe itself" and by observing, "Every child has wondered at some time where we came from and how we got here." Editorialists at the Chicago Tribune were among others who adopted that creation-investigation theme. They wrote, "All of this leads to the scientific grail: understanding the birth of the cosmos and all the forces that rule in it."
US News published responses to the LIGO news by nine physicists from Africa, Australia, Europe, and the US. Some of the coverage resembled the Guardian's article "Explain it to me like I'm a kid: Scientists try to make sense of gravitational waves" by physicists from four US universities. Business Insider Australia celebrated by publishing a photo showing an original handwritten equation from the Hebrew University of Jerusalem's Albert Einstein Archives.
Times DotEarth columnist Andrew Revkin invited views from climate scientist Raymond Thomas Pierrehumbert, Halley Professor of Physics at Oxford. Pierrehumbert's 10-paragraph contribution began, "The day of the release of the spectacular LIGO gravitational wave discovery is a good time to be pondering human destiny, the great things we can achieve as a species if only we don't do ourselves in, and the responsibility to provide a home for future generations to flourish in."
At the business site Forbes.com, Berkeley physicist Richard A. Muller—author of Energy for Future Presidents (W. W. Norton, 2012), known also for his 2012 New York Times op-ed "The conversion of a climate-change skeptic"—explained that "the reason they are called 'gravitational waves' and not 'gravity waves' is that 'gravity waves' refers to ordinary water waves and other phenomena that depend on gravity." He continued: "If there were no gravity, and you splashed water, the splash would just stay; it wouldn't move away from the splash point. So to differentiate gravitational waves, they are called gravitational, not gravity. But, among physicists, in ordinary conversation, they are frequently just called gravity waves."
Also at Forbes.com, physicist and physics columnist Chad Orzel explained why he believes the LIGO news "is the most exciting development in recent physics," immediately adding that "it's nothing to do with Einstein." Orzel continued:
In fact, confirming General Relativity is just about the least interesting part of this news. The really important story is that LIGO works, and allows the unequivocal detection of colliding black holes, a system that physicists understand pretty well. And it continues to work, with additional gravitational-wave events being analyzed now. This means that when it starts detecting other things that we don't immediately recognize, physicists can have some confidence that they're real, and not just a weird quirk of the detector that we don't understand yet.
Orzel also observes that "a huge undertaking like LIGO connects to and stimulates research in other, unexpected places." He cites "cool experiments probing the fundamental quantum nature of things in part because astrophysicists looking for gravitational waves want to keep their mirrors stable." He adds, "And, in turn, we may someday end up with an even-more-sensitive gravitational wave detector thanks to the efforts of people looking at quantum effects in tiny vibrating membranes."
"Cool"? The New York Times's celebratory editorial used that word too, working it into a paragraph conveying a technopolitical message as well:
By coincidence, at about the same time that the LIGO discovery was announced, the House passed a bill requiring that National Science Foundation grants be justified "in the national interest." It is doubtful that LIGO would have survived such political meddling. The bottom line is that whatever else it may be or lead to, the story of the chirp heard round the universe is simply cool. For proof, just listen to that little song.
In a US News opinion piece, France Córdova—director of NSF and an astrophysicist whose PhD thesis committee at Caltech had included Thorne—argued that the discovery shows that funding for basic research is vital. Concerning a research payoff, Stephen Hawking told BBC, "Gravitational waves provide a completely new way of looking at the universe. The ability to detect them has the potential to revolutionize astronomy."
That notion is common in the media coverage. Astronomy now can use gravitational waves along with light waves and radio waves. At Nature, Davide Castelvecchi posted the article "Gravitational waves: 6 cosmic questions they can tackle." The subhead declared that the "discovery of ripples in space-time has vindicated Einstein—but it can also do so much more." Castelvecchi observed that in LIGO's original struggle for funding in the early 1990s, "its major opponents at congressional hearings were astronomers." Now, however, the experiment's success invites deeper attention to the six questions: Do black holes actually exist? Do gravitational waves travel at the speed of light? Is space-time made of cosmic strings? Are neutron stars rugged? What makes stars explode? How fast is the universe expanding?
A few days after that piece appeared, Nature posted Alexandra Witze's article "Young scientists poised to ride the gravitational wave: Detection of ripples in space-time kicks off new era in physics." Concerning the hoped-for "more complete picture of how gravitational waves and conventional astronomy come together," the article's ending offered this simile: "It's like seeing a film in which the combination of images (electromagnetic waves) and sound (gravitational waves) provides a much fuller picture than either could alone, says Alessandra Corsi, an astrophysicist at Texas Tech University in Lubbock. 'It feels incredibly exciting to be right at the start of a new era.'"
Was the LIGO news overhyped? Denver Post reader Joel C. Boulder of Littleton, Colorado, thought so. He charged in a letter to the editor that in "terms of its practical significance, some science jocks spent $1.1 billion on a machine that occasionally makes a chirp that sounds 'more like a thud' and has a limited resale market." He added, "If, in fact, these gravitational waves were created by a collision of two black holes 1.3 billion years ago, it strikes me that the skies have been the same since before the dawn of mankind and are unlikely to change anytime soon."
Overhyped? A Daily Beast piece asserted that "the LIGO researchers just made great strides toward understanding time travel."
At the Scientific American website, John Horgan—author 20 years ago of The End of Science: Facing the Limits of Knowledge in the Twilight of the Scientific Age (Addison-Wesley)—examined what he called a "curmudgeonly" question: Was it really worth $1.1 billion just to confirm what wasn't being questioned anyhow? His own answer is yes. He predicted, "Gravitational-wave astronomy could be exactly what physics needs."
Overhyped or not, the LIGO news stimulated interest worldwide. China Daily USA reported on 17 February that the news "has encouraged scientists around the world, with China set to accelerate research," and that "Chinese scientists are proposing a space gravitational wave detection project." Pakistan Today emphasized that the LIGO advance had involved Pakistani physicists Imran Khan and Nergis Mavalvala. In New Delhi, the Hindu, echoed by the Times of India, reported within a week of the news announcement that a "mega science proposal for research on gravitational waves" in collaboration with LIGO had received "in-principle approval" from the Indian government.
Maybe it was a fear of overhyping the news that led New York Times reporter Jonah Bromwich to consult Krauss about "four of Einstein's notable blunders." The resulting online article addressed the following:
* Einstein's rejection of quantum entanglement, which Einstein called "spooky action at a distance."
* His disbelief in the possibility of observing gravitational lensing.
* The cosmological constant that he proposed in the era before it was understood that the universe expands.
* His wish, 20 years after proposing the existence of gravitational waves, to retract the proposal.
Concerning that last one, Bromwich quoted a "chuckling" Krauss: "He wanted to retract the very thing we just discovered this year. I think it's a nice bit of poetry."
Steven T. Corneliussen, a media analyst for the American Institute of Physics, monitors three national newspapers, the weeklies Nature and Science, and occasionally other publications. He has published op-eds in the Washington Post and other newspapers, has written for NASA's history program, and is a science writer at a particle-accelerator laboratory.