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Artist's concept of the black hole. |
Of all the bizarre quirks of nature, supermassive black holes are some of the most mysterious because they're completely invisible.
But that could soon change.
Black holes are deep wells in the fabric of space-time that eternally trap anything that dares too close, and supermassive black holes have the deepest wells of all. These hollows are generated by extremely dense objects thousands to billions of times more massive than our sun.
Not even light can escape black holes, which means they're invisible to any of the instruments astrophysicists currently use. Although they don't emit light, black holes will, under the right conditions, emit large amounts of gravitational waves — ripples in spacetime that propagate through the universe like ripples across a pond's surface.
And although no one has ever detected a gravitational wave, there are a handful of instruments around the world waiting to catch one.
Game-changing gravitational waves
This illustration shows two spiral galaxies - each with supermassive black holes at their center - as they are about to collide.
Albert Einstein first predicted the existence of gravitational waves in 1916. According to his theory of general relativity, black holes will emit these waves when they accelerate to high speeds, which happens when two black holes encounter one another in the universe. As two galaxies collide, for example, the supermassive black holes at their centers will also collide. But first, they enter into a deadly cosmic dance where the smaller black hole spirals into the larger black hole, moving increasingly faster as it inches toward it's inevitable doom. As it accelerates, it emits gravitational waves.
Astrophysicists are out to observe these waves generated by two merging black holes with instruments like the Laser Interferometer Gravitational-Wave Observatory.
"The detection of gravitational waves would be a game changer for astronomers in the field," Clifford Will, a distinguished profess of physics at the University of Florida who studied under famed astrophysicist Kip Thorne told Business Insider. "We would be able to test aspects of general relativity that have not been tested."
Because these waves have never been detected, astrophysicists are still trying to figure out how to find them. To do this, they build computer simulations to predict what kinds of gravitational waves a black hole merger will produce.
Learn by listening
In the simulation below, made by Steve Drasco at California Polytechnic State University (also known as Cal Poly), a black hole gets consumed by a supermassive black hole about 30,000 times as heavy.
You'll want to turn up the volume.
What you're seeing and hearing are two different things.
The black lines you're seeing are the orbits of the tiny black hole traced out as it falls into the supermassive black hole. What you're hearing are gravitational waves.
"The motion makes gravitational waves, and you are hearing the waves," Drasco wrote in a blog post describing his work.
Of course, there is no real sound in space, so if you somehow managed to encounter this rare cataclysmic event, you would not likely hear anything. However, what Drasco has done will help astrophysicists track down these illusive waves.
Just a little fine tuning
Gravitational waves are similar to radio waves in that both have specific frequencies. On the radio, for example, the number corresponding to the station you're listening to represents the frequency at which that station transmits.
3D visualization of gravitational waves produced by 2 orbiting black holes. Right now, astrophysicists only have an idea of what frequencies two merging black holes transmit because they’re rare and hard to find. In fact, the first ever detection of an event of this kind was only announced this month.
Therefore, astrophysicists are basically toying with their instruments like you sometimes toy with your radio to find the right station, except they don’t know what station will give them the signal they’re looking for.What Drasco has done in his simulation is estimate the frequency at which an event like this would produce and then see how that frequency changes, so astrophysicists have a better idea of how to fine tune their instruments to search for these waves.
Detecting gravitational waves would revolutionize the field of astronomy because it would give observers an entirely new way to see the universe. Armed with this new tool, they will be able to test general relativity in ways never before made possible.
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Google Chairman Eric Schmidt: "The Internet Will Disappear"
Excerpt from hollywoodreporter.com
Google executive chairman Eric Schmidt on Thursday predicted the end of the Internet as we know it.
At the end of a panel at the World Economic Forum in Davos, Switzerland, where his comments were webcast, he was asked for his prediction on the future of the web. “I will answer very simply that the Internet will disappear,” Schmidt said.
“There will be so many IP addresses…so many devices, sensors, things that you are wearing, things that you are interacting with that you won’t even sense it,” he explained. “It will be part of your presence all the time. Imagine you walk into a room, and the room is dynamic. And with your permission and all of that, you are interacting with the things going on in the room.”
Concluded Schmidt: “A highly personalized, highly interactive and very, very interesting world emerges.”
The panel, entitled The Future of the Digital Economy, also featured Facebook COO Sheryl Sandberg and others.
Earlier in the debate, Schmidt discussed the issue of market dominance. The European Union has been looking at Google’s search market dominance in a long-running antitrust case, and the European parliament late last year even called for a breakup.
Asked about his recent trip to North Korea, Schmidt said the country has many Internet connections through data phones, but there is no roaming and web usage is “heavily supervised.” Schmidt said “it’s very much surveillance of use,” which he said was not good for the country and others.
Sandberg and Schmidt lauded the Internet as an important way to give more people in the world a voice. Currently, only 40 percent of people have Internet access, the Facebook COO said, adding that any growth in reach helps extend people’s voice and increase economic opportunity. “I’m a huge optimist,” she said about her outlook for the industry. “Imagine what we can do” once the world gets to 50 percent, 60 percent and more in terms of Internet penetration.
Schmidt similarly said that broadband can address governance issues, information needs, personal issues, women empowerment needs and education issues. “The Internet is the greatest empowerment of citizens … in many years,” he said. “Suddenly citizens have a voice, they can be heard.”
During another technology panel at the World Economic Forum on Thursday, Yahoo CEO Marissa Mayer, Liberty Global CEO Mike Fries and others answered questions on the need to regulate privacy standards on the Internet and for tech companies following the Snowden case, the Sony hack and the like.
Mayer said that the personalized Internet “is a better Internet,” emphasizing: “We don’t sell your personal data … We don’t transfer your personal data to third parties.” She said users own their data and need to have control, adding that people give up data to the government for tax assessment, social services and other purposes.
Both executives said transparency was important to make sure users know privacy standards and the like.
Gunther Oettinger, a conservative German politician serving as the European Union’s commissioner for digital economy and society, said on the panel that “we need a convincing global understanding, we need a UN agency for data protection and security.” Asked what form that “understanding” should have, he said he was looking for “clear, pragmatic, market-based regulation.” Explained Oettinger: “It’s a public-private partnership.”
Fries said such a solution was likely not to happen in the near term, given the size of the EU. “I think it is going to take several years,” he said, adding that some countries’ parliaments would likely take a stab at it.
But he warned that a joint solution would make more sense. “We don’t want Germany to have its own Internet,” Fries said. “Some countries may build their own Internets” and “balkanize” the web, he warned.
Mayer said on the issue of regulation: “I like Tim’s idea better of the beneficent marketplace.” She spoke of fellow panelist and computer specialist Tim Berners-Lee, known as the inventor of the World Wide Web.
Asked how Yahoo stores and handles client records, she said the online giant “changed the way we store and communicate data” after Snowden and also changed encryptions between data centers. And the company protects users through encryption methods, she added. Mayer said that trust and confidence of Yahoo users has rebounded since.
Mayer was also asked what happens if a government asks for a user’s data, a question that has new significance after the recent terrorist attacks in Paris, which have led some to call for increased surveillance powers of the Internet for governments. Mayer said Yahoo always assesses if such a request is reasonable. “We have a very good track record for standing up to what’s not reasonable,” she said.
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