Bring4th

The Guardian Wrote:Scientists struggle to stay grounded after possible gravitational wave signal

Cosmologist’s tweet appears to confirm rumours of discovery that could ‘open a new window on the universe’

Not for the first time, the world of physics is abuzz with rumours that gravitational waves have been detected by scientists in the US.

Lawrence Krauss, a cosmologist at Arizona State university, tweeted that he had received independent confirmation of a rumour that has been in circulation for months, adding: “Gravitational waves may have been discovered!!”

The excitement centres on a longstanding experiment known as the Advanced Laser Interferometer Gravitational-Wave Observatory (Ligo) which uses detectors in Hanford, Washington, and Livingston, Louisiana to look for ripples in the fabric of spacetime.

According to the rumours, scientists on the team are in the process of writing up a paper that describes a gravitational wave signal. If such a signal exists and is verified, it would confirm one of the most dramatic predictions of Albert Einstein’s century-old theory of general relativity.

Krauss said he was 60% confident that the rumour was true, but said he would have to see the scientists’ data before drawing any conclusions about whether the signal was genuine or not.

Researchers on a large collaboration like Ligo will have any such paper internally vetted before sending it for publication and calling a press conference. In 2014, researchers on another US experiment, called BICEP2, called a press conference to announce the discovery of gravitational waves, but others have since pointed out that the signal could be due entirely to space dust.

Speaking about the LIGO team, Krauss said: “They will be extremely cautious. There’s no reason for them to make a claim they are not certain of.”

If gravitational waves have been discovered, astronomers could use them to observe the cosmos in a way that has been impossible to date. “We would have a new window on the universe,” Krauss said. “Gravitational waves are generated in the most exotic, strange locations in nature, such as at the edge of black holes at the beginning of time. We are pretty certain they exist, but we’ve not been able to use them to probe the universe.”

Einstein predicted that the waves would be produced in extremely violent events, such as collisions between two black holes. As gravitational waves spread out, they compress and stretch spacetime. The ripples could potentially be picked up by laser beams that measure minute changes in the lengths of two 4km-long pipes at the Ligo facilities.

Engineers occasionally add synthetic signals to the Ligo data to test the equipment. While these are designed to mimic gravitational wave signals, Krauss said he had heard explicitly that the signal had not been added artificially.

“I don’t know if the rumour is solid,” Krauss told the Guardian. “If I don’t hear anything in the next two months, I’ll conclude it was false.”

Gabriela Gonzalez, professor of physics and astronomy at Louisiana State University, and the spokesperson for the LIGO collaboration, told the Guardian: “The LIGO instruments are still taking data today, and it takes us time to analyse, interpret and review results, so we don’t have any results to share yet.

“We take pride in reviewing our results carefully before submitting them for publication - and for important results, we plan to ask for our papers to be peer-reviewed before we announce the results - that takes time too!” she said.

This article was updated on 12 January 2016 to include a response from the spokesperson for the LIGO collaboration.

Source: The Guardian/UK, 12 January 2016

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LIGO Detects Gravitational Waves from Merging Black Holes

LIGO Wrote:Gravitational radiation has been directly detected. The first-ever detection was made by both facilities of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Washington and Louisiana simultaneously last September. After numerous consistency checks, the resulting 5-sigma discovery was published today. The measured gravitational waves match those expected from two large black holes merging after a death spiral in a distant galaxy, with the resulting new black hole momentarily vibrating in a rapid ringdown. A phenomenon predicted by Einstein, the historic discovery confirms a cornerstone of humanity's understanding of gravity and basic physics. It is also the most direct detection of black holes ever. The featured illustration depicts the two merging black holes with the signal strength of the two detectors over 0.3 seconds superimposed across the bottom. Expected future detections by Advanced LIGO and other gravitational wave detectors may not only confirm the spectacular nature of this measurement but hold tremendous promise of giving humanity a new way to see and explore our universe.

Source: APOD, February 22 2016

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Gravitational waves announcement: Scientists confirm they have seen ripples in the fabric of spacetime
Scientists say that the discovery is the biggest of the century — far more important than that of the Higgs boson

'With gravitational wave detection, we can now listen to the stars'

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I wonder what Ra would say about what black holes merging means from a higher-dimensional perspective. That might even be an interesting question to toss at Q'uo in a session.

I am interested to see what sort of discoveries come from this. Apparently, this technology will let us learn a lot more about stars. One big thing about Dewey Larson's theory, which Ra uses as a reference to describe things like space/time and time/space, is that it would require a much different model for how stars are formed and die than what is accepted by the modern scientific community. It would be neat if this somehow overturned the current theories and vindicated Larson's work, if those parts were indeed true.

I'm not sure what to think about this. I believe that what these scientists think they know about gravity is wrong. I believe Gravity is connected to electromagnetism and that antigravity is not only possible but has been done. So what does this say exactly? That gravity moves at the speed of light? They still don't understand gravity, but then again nor do they understand electromagnetism.

(02-14-2016, 02:51 PM)1109 Wrote: [ -> ]I'm not sure what to think about this. I believe that what these scientists think they know about gravity is wrong. I believe Gravity is connected to electromagnetism and that antigravity is not only possible but has been done. So what does this say exactly? That gravity moves at the speed of light? They still don't understand gravity, but then again nor do they understand electromagnetism.

So far as I understand it, this isn't necessarily a discovery which changes the scientific community's idea of gravity. Contrarily, it confirms the theory they've been working with for many decades (Einstein's relativity). It is primarily a new way to detect gravity. Similar to how the microscope or telescope opened up an entire new layer of reality to our perception, this creates a new portal through which to view the universe. If they are wrong about gravity, this will help them realize it. If there are new discoveries to be made about gravity, this will help usher them in.

Or watch/download the original at TED: Allan Adams: What the discovery of gravitational waves means

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Quest to settle riddle over Einstein's theory may soon be over

Quote:Astronomy experiments could soon test an idea developed by Albert Einstein almost exactly a century ago, scientists say. Tests using advanced technology could resolve a longstanding puzzle over what is driving the accelerated expansion of the Universe.

Researchers have long sought to determine how the Universe's accelerated expansion is being driven. Calculations in a new study could help to explain whether dark energy- as required by Einstein's theory of general relativity - or a revised theory of gravity are responsible.

Einstein's theory, which describes gravity as distortions of space and time, included a mathematical element known as a Cosmological Constant. Einstein originally introduced it to explain a static universe, but discarded his mathematical factor as a blunder after it was discovered that our Universe is expanding.

Research carried out two decades ago, however, showed that this expansion is accelerating, which suggests that Einstein's Constant may still have a part to play in accounting for dark energy. Without dark energy, the acceleration implies a failure of Einstein's theory of gravity across the largest distances in our Universe.

Scientists from the University of Edinburgh have discovered that the puzzle could be resolved by determining the speed of gravity in the cosmos from a study of gravitational waves -space-time ripples propagating through the universe.

The researchers' calculations show that if gravitational waves are found to travel at the speed of light, this would rule out alternative gravity theories, with no dark energy, in support of Einstein's Cosmological Constant. If however, their speed differs from that of light, then Einstein's theory must be revised.

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