A 'magical' space-time ripple that wasn't believed, at first

February 11, 2016
A screen displays a diagram showing the ripples in the fabric of spacetime called gravitational waves that scientists have obser
A screen displays a diagram showing the ripples in the fabric of spacetime called gravitational waves that scientists have observed for the first time during a press conference at the National Press Club in Washington, DC, February 11, 2016

The wave that made history snuck up on them. David Shoemaker will never forget the date—September 14, 2015—when he woke up to a message alerting him that an underground detector had spotted a 1.3-billion-year-old ripple in the fabric of space-time.

A gravitational wave—predicted to exist a century ago by Albert Einstein—had been glimpsed directly for the first time by a pair of US-based detectors.

"It is seared in my brain," said Shoemaker, a top scientist at the Massachusetts Institute of Technology (MIT) and head of the Advanced LIGO Project, an international effort to uncover evidence of gravitational waves.

Such waves are a measure of strain in space, an effect of the motion of large masses that stretches the fabric of space-time—a way of viewing space and time as a single, interweaved continuum.

The "chirp," as Shoemaker described the long-awaited wave, had arrived while he was asleep.

But since the data analysis works in quasi-real-time, scientists watching the data stream early in the work day in Europe saw it immediately.

Two black holes spiraling into each other became a single black hole, and the joining of these two giants curved the fabric of space-time around them, ever so briefly.

"When the signal finally got to the Earth on September 14 we knew within three minutes that our instruments had seen something really different," said Shoemaker.

"I was sitting at home, with a cup of coffee in my hand and opening up my email at around 7 am," he told AFP.

An instant message had arrived from a close colleague in Germany.

The message said: "I think we are in trouble now," he recalled.

But Shoemaker, a leading scientist in the search for gravitational waves since the early 1980s, did not leap out his chair or shout expletives.

He just took a deep breath.

"My immediate reaction was, 'That's fascinating. Let's see what the instruments did wrong.'"

Gravitational waves detected
Grapihc explaining what gravitational waves are and how they can be detected

Taken by surprise

In fact, the team had only just turned on the pair of underground detectors—one in Louisiana and one in Washington state—for a series of final checks before formally starting the observation experiment, which would run from mid September until January.

"It was just at the beginning of this run, when we were all ready to go—to press the button to start the observing run—that the gravitational wave was observed," he said.

"So it was a very exciting moment for us and it took us perfectly by surprise."

Immediately, Shoemaker and colleagues began running through a checklist of possible failures.

One by one, they ruled out electromagnetic storms, lighting strikes, earthquakes, or interference by people near sensitive parts of the instruments.

Furthermore, the timing matched up.

The detector in Hanford, Washington picked up the signal 7.1 after the Livingston, Louisiana instrument, some 1,800 miles (3,000 kilometers) away.

"The travel time of light between the two instruments is 10 milliseconds," said Shoemaker.

"And if the two signals had arrived 11 milliseconds apart, we would have simply said, 'Nope. It's two instrumental defects that happened at the same time.'

"But it happened within 7.1 milliseconds, which is a perfectly plausible delay between the two."

Weeks of tests

After many tests, the LIGO team's discovery was confirmed.

"It took weeks before we were really gaining confidence that it was a true gravitational wave event, before I could admit to myself that something had been seen," Shoemaker said.

"But, you know, eventually, joy sets in."

The LIGO work is vastly different from that done by US astrophysicists who announced in 2014 they had detected the first ripples from the Big Bang, then months later admitted their indirect, telescope-based findings were premature and could not be confirmed.

Shoemaker and colleagues are using different equipment to hunt for much smaller, shorter waves, on the order of milliseconds or seconds. In other words, the kinds of that happen all the time, but had never before been observed.

"This is the first time there has ever been a direct detection of the gravitational waveform," Shoemaker said.

"And that makes it a magical thing."

Explore further: Video: The hunt is on for gravitational waves

More information: phys.org/news/2016-02-gravitational-years-einstein.html

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32 comments

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andyf
4.6 / 5 (5) Feb 11, 2016
Great news!
Just one small point: they aren't underground.
cantdrive85
1.2 / 5 (21) Feb 11, 2016
They must be magical considering the fact that there is neither a "fabric of space-time" nor do BH's exist anywhere but in a mathematician's fanciful imagination.
Captain Stumpy
4.3 / 5 (17) Feb 11, 2016
They must be magical considering the fact that there is neither a "fabric of space-time" nor do BH's exist anywhere but in a mathematician's fanciful imagination.
@cd
continuously repeating lies doesn't make them more true
evidence rules- it also proves you wrong, ignorant and full of religious like beliefs: http://journals.a...fulltext

one more nail in the coffin of eu, and further evidence that you are no more than a fanatical religious acolyte!

retrosurf
5 / 5 (5) Feb 11, 2016
The *detectors* actually are underground, no doubt for shielding.
The arms of the instrument are on the surface.
baudrunner
1.4 / 5 (10) Feb 11, 2016
Actually there is a fabric of space-time, and major events like supernovas and colossal collisions of massive bodies or black holes in space can produce shock waves of great enough intensity to detect as ripples in that space-time fabric. But if the researchers had the correct understanding of gravity and what it is and how it works then they wouldn't be calling those ripples gravity waves.

The late Paolo Maffei, the noted Italian astronomer, wrote in one of his books that if a neighboring galaxy were to explode that we would feel the initial shock wave within a couple of days of that event. Think about it.
andyf
4.3 / 5 (11) Feb 11, 2016
It is to be regretted that this site does not allow a rating of 0/5 for posts that are simply wrong.
andyf
not rated yet Feb 11, 2016
@retrosurf: Thanks for the correction! Can you point me to an article/whatever that affirms your POV? It would be much appreciated as I haven't yet found any detailed descriptions of the optical arrangement of the LIGO instruments.

I must admit that if I were designing one of these, I'd avoid using any unnecessary (?) mirrors to get the sensor underground. Each one would be an extra noise source. I'd put a massive concrete foundation underneath the detectors and add shielding over the top.
Hyperfuzzy
1 / 5 (5) Feb 11, 2016
I get it. If we convince people that magic exists, we'll be able to reproduce the Machiavellian belief in God!
Hyperfuzzy
1 / 5 (3) Feb 11, 2016
It should be noted, large concentrations of matter and black holes are two different things. Large concentrations may be of any size you may call large enough. Black Holes are a singularity, only one solution therefore all the same size, zero with varying theories on the event horizon. The event horizon is a disproof all by itself that it's just a bunch of matter larger than ... oh, for goodness sake, whatever. Fabric of space-time!??
andyf
5 / 5 (2) Feb 11, 2016
Niccolo Machiavelli didn't show any belief in either God or magic.
andyf
5 / 5 (4) Feb 11, 2016
Hyperfuzzy didn't show any comprehension of anything.
Phys1
4.3 / 5 (11) Feb 11, 2016
The late Paolo Maffei, the noted Italian astronomer, wrote in one of his books that if a neighboring galaxy were to explode that we would feel the initial shock wave within a couple of days of that event. Think about it.

I thought about it. He was wrong.
rocketman_37
5 / 5 (4) Feb 11, 2016
The late Paolo Maffei, the noted Italian astronomer, wrote in one of his books that if a neighboring galaxy were to explode that we would feel the initial shock wave within a couple of days of that event. Think about it.

I don't know when or where he stated that - but since the 'shock wave' wouldn't be traveling faster than the speed of light - it would be millions of years before we detected the 'explosion' of a nearby galaxy (not sure what they even means)
KBK
1.5 / 5 (2) Feb 12, 2016
The late Paolo Maffei, the noted Italian astronomer, wrote in one of his books that if a neighboring galaxy were to explode that we would feel the initial shock wave within a couple of days of that event. Think about it.

I thought about it. He was wrong.


There is no wrong. Only high improbability. As soon as wrong, or facts exist -science devolves into dogma.

Engineers have facts, people have facts -science cannot have any facts, otherwise it has spiraled into religious terminal dogma. (no future)

I've just recently met with three different physics and hard sciences department heads at a major university. All three agree wholeheartedly that there is no such thing as a fact, that all science is theory at best, and all teach their students the same, no exceptions.

So one wonders where this garbage of 'factualizing' comes from.

It can only stem from illiteracy, or trolling to enforce dogma --- by private/government interests.
antialias_physorg
4 / 5 (4) Feb 12, 2016
The late Paolo Maffei, the noted Italian astronomer, wrote in one of his books that if a neighboring galaxy were to explode that we would feel the initial shock wave within a couple of days of that event.

An event would be observation. All he was saying here is that some particles of the shock wave would travel at close to c and so we would feel the shock a few days after observing the event. While such speeds are mindboggling they aren't at odds with anything we know about physics.
KBK
1 / 5 (2) Feb 12, 2016
The late Paolo Maffei, the noted Italian astronomer, wrote in one of his books that if a neighboring galaxy were to explode that we would feel the initial shock wave within a couple of days of that event.

An event would be observation. All he was saying here is that some particles of the shock wave would travel at close to c and so we would feel the shock a few days after observing the event. While such speeds are mindboggling they aren't at odds with anything we know about physics.


There's a whole bunch of work by Nikolai Kozyrev and others that says quite clearly that FTL's are real and wholly measurable. This sort of reality is dangerous for controlled sciences.

Science is fine, it's the enforced dogma from oligarchical interests that are the problem. Science in the form of communicating with the public, is filled with projected dogmatic limitations on reality and it's potentials.

This is obvious to anyone who is paying attention.
Scroofinator
5 / 5 (1) Feb 12, 2016
Correct me if I'm wrong, but how does one experiment for ether (Michelson/Morley) differ from another experiment looking for gravitational waves (LIGO) in a fundamental way other than being more precise?
baudrunner
1 / 5 (2) Feb 13, 2016
All he was saying here is that some particles of the shock wave would travel at close to c and so we would feel the shock a few days after observing the event.
I think you wrote this before your morning coffee. The nearest galaxy is about 2 million light years away.

Which brings me back to superluminal velocities once again. I am pulling this from another post of mine. "The speed of light is described as, "the single limiting velocity in the universe, being an upper bound to the propagation speed of signals and to the speeds of all material particles." What in that statement requires gravity to be affected by this limit? I can't find anything in current thinking that describes gravity as a signal, and I certainly can't read into any of it that gravity is a material particle. So, why should gravity be limited by distance?" Or the single limiting velocity in the universe, for that matter.
baudrunner
1 / 5 (3) Feb 13, 2016
I don't know when or where he stated that - but since the 'shock wave' wouldn't be traveling faster than the speed of light - it would be millions of years before we detected the 'explosion' of a nearby galaxy (not sure what they even means)
Again, I am reading the assumption that because there is an upper limit to the propagation of light waves and to particles traveling in space that there is nothing that can exceed that limit. That is bogus thinking. Shock waves are neither light waves nor are they particle waves.

On another point, why shouldn't we be allowed to travel faster than c in a star ship, say? "To every action there is an equal and opposite reaction." Is that except when we are traveling at c? Who says? Concorde passengers had no trouble communicating with one another, even though they were flying at mach 2. The plane was its own inertial frame of reference, you see.
Phys1
3.7 / 5 (3) Feb 13, 2016
@KBK
There is no wrong

There is: Paolo Maffei.
FTL's are real and wholly measurable

That explains the lecture that everyone is right and that there are no facts at all !
You are pushing pseudoscience. See, now I can not say the crackpots have it wrong.
it's the enforced dogma from oligarchical interests that are the problem

I am not dogmatic and, unfortunately, not an oligarch (I would have had you banned).
Phys1
5 / 5 (3) Feb 13, 2016
I can't find anything in current thinking that describes gravity as a signal, and I certainly can't read into any of it that gravity is a material particle. So, why should gravity be limited by distance?" Or the single limiting velocity in the universe, for that matter.

If gravitational waves travel faster than light, that would overthrow SR/GRT.
Very few believe that will happen, but unless coincident events in gravitational and EM waves are found, no one can be sure. It is just a matter of time now before we will find out.
baudrunner
1 / 5 (4) Feb 13, 2016
If gravitational waves travel faster than light, that would overthrow SR/GRT.
How? The notion that the upper limit of the rate of light propagation should be applied to material particles is an addendum by overenthusiastic physics fans. It has perpetuated to pollute the perceptions of the unwitting.

The thought experiment that freaked Einstein out was that if he were traveling at faster than light speed, he would be inexplicably blinded because light would lag behind at the rate that he was traveling. That's actually a false assumption. He never flew in the Concorde! He neglected to remind himself that he would have been observing from within his own inertial and static frame of reference!
Phys1
5 / 5 (2) Feb 13, 2016
You do not understand pysics and not all your sentences are comprehensible.
Anyway, read https://sciencex....4412982.
Gravitons move at c.
baudrunner
1 / 5 (2) Feb 13, 2016
Everything is in motion in this universe and the only inertial, static frame of reference is the one that you're in. Two objects traveling at near-light speed (to satisfy the trolls) and moving in opposite directions from one another are each traveling at a multiple of that speed relative to the other. No transgression of SR/GRT here.
baudrunner
1 / 5 (1) Feb 13, 2016
Gravitons move at c
You do not understand physics, you merely reiterate the falsehoods of others. Gravitons do not exist, any more than there is a particle that confers mass on other particles, as many people have reiterated, even though recent experimental evidence makes that particular notion highly suspect... http://phys.org/n...ies.html
Phys1
5 / 5 (2) Feb 13, 2016
@br
yeah right you are so brilliant, why don't you give yourself a Nobel prize.
btw when you say physics, do you mean your crackpottery? Indeed I do not understand it.
Phys1
5 / 5 (3) Feb 13, 2016
If gravitational waves travel faster than light, that would overthrow SR/GRT.
How?

Aha, so you do not understand the first thing about SR and GRT.
del2
5 / 5 (4) Feb 13, 2016
Everything is in motion in this universe and the only inertial, static frame of reference is the one that you're in. Two objects traveling at near-light speed (to satisfy the trolls) and moving in opposite directions from one another are each traveling at a multiple of that speed relative to the other. No transgression of SR/GRT here.

No, you can't just add velocities in SR. If A is travelling at 0.5c (relative to you) and B is travelling at 0.5c in the opposite direction, then A would measure B's velocity as 0.8c.
See for example https://en.wikipe...lativity
Mike_Massen
5 / 5 (1) Feb 14, 2016
Scroofinator ask
.. one experiment for ether (Michelson/Morley) (MM) differ from another experiment looking for gravitational waves..
Former, searches for aether effect by locally initiating energy continuously & rotating interferometer to measure Δ c

Latter, measures distant gravitational stress in effect on ostensibly static (4Km) lengths using interferometer to measure Δ length

ie Interferometer just a very precise measuring tool for speed/length

Note "..all things observed propagate waves of Δ energy Eg solids-> acoustic, water->ripples, gases->light/acoustic, space->light etc All matter & non matter alike does propagate Δ energy.."

Therefore, regardless of Einstein (E), universality of energy propagation suggests waves would exist, key is E's field equations ~100yrs have been able to quantify effect with high level of precision...

Could use many LIGOs if a Δ G occurs often over Earth orbit & for DM effect too if correlated globally & precise enough !
baudrunner
1 / 5 (3) Feb 15, 2016
Another confusing and much reiterated fact is that particles are waves. Not so. A particle is a particle is a confined domain of energy. You need a sea of them to observe wave behavior.

Also, c is the upper limit of the speed of light. The idea that nothing can exceed that velocity is another popular reiteration of misleading information. For example, Cherenkov radiation occurs when electrons travel faster than light in a heavy water medium in which the upper limit of c is 75% of its velocity in air. But, water is just another medium, so air is just another medium, in which there exists another upper limit to c. Just another medium, and nothing magical about c that should constrain the velocity of anything other than light to that limit. Do you see the logic?
SteveS
5 / 5 (2) Feb 16, 2016
Also, c is the upper limit of the speed of light.


c is the upper limit of the speed of light....in a vacuum. The definition is precise.
Phys1
5 / 5 (2) Feb 16, 2016
br, you are like an elephant is a porcelain shop.

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