Thursday, February 11, 2016

LIGO Detects Black Hole Merger

The near simultaneous signal detection at both LIGO installations almost certainly precludes the possibility of an artifact.

On September 14, 2015, the two LIGO (Laser Interferometer Gravitational-Wave Observatory)* installations — one at Hanford Washington, the other at Livingston, Louisiana. recorded near simultaneous signals attributed to gravity waves generated by the merger of two black holes with masses estimated to be 29 and 36 times that of the sun.

The event, which occurred at a distance of 1.3 billion light years, i.e., 1.3 billion years ago, is estimated to have converted mass equivalent to three times that of the sun to gravitational wave energy within less than a second, resulting in a peak power output many times that of all other energy sources in the visible universe.

The signal received at Livingston, arrived 7 milliseconds before the signal received at Hanford, indicating that the source was located in the southern Hemisphere.

All reports attribute the observations reported by LIGO to ripples in the fabric of space-time caused by the rotation and merger of black holes. Implicit to this interpretation is the notion that space is not empty but filled with a medium, or ether, in which gravity waves propagate.

This seems remarkably in view of the rejection by the physics community of Newton's luminiferous ether following the Michelson Morley experiment conducted in 1887, which demonstrated that the velocity of light was independent of its direction of travel from a source in motion relative to the ether. If light waves can traverse the vacuum without a medium to wave in, why not gravity waves  too?

That argument, notwithstanding, Einstein held the existence of a medium in space in which gravity waves propagate to be necessary, a medium or ether now generally identified with the spacetime continuum implicit in Einstein's general theory of relativity. But not everyone agrees, and here. These ideas may seem slightly wacky, but they make me feel slightly better about proposing that space really is space, i.e., the absence of anything, and that any properties attributed to space are due to whatever happens to have been added thereto, dark energy, for example, or virtual particles. Not that I'd bet more than about 50 cents against Einstein. But then even Einstein had moments of doubt, remarking at one point:
Perhaps, ... we must also give up, by principle, the space-time continuum. It is not unimaginable that human ingenuity will some day find methods which will make it possible to proceed along such a path."
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* The LIGO detectors measure the distance between mirrors located in an evacuated tube at a distance of 4 km from one another. They are able to detect variation in distance between the mirrors equal to less than one ten thousandth the diameter of a proton, which is why the project has cost hundreds of millions of dollars!

Related:

Quanta Magazine: From Einstein’s Theory to Gravity’s Chirp

Physical Review Letter:

B.P. Abbot, et al. 2016: Observation of Gravitational Waves from a Binary Black Hole Merger

LIGO Caltech:

Gravitational Waves Detected 100 Years After Einstein's Prediction

12 comments:

  1. Gravity travels faster than light.

    " anyone with a computer and orbit computation or numerical integration software can verify the consequences of introducing a delay into gravitational interactions. The effect on computed orbits is usually disastrous because conservation of angular momentum is destroyed."

    "How can black holes have gravity when nothing can get out because escape speed is greater than the speed of light?"

    http://www.metaresearch.org/cosmology/speed_of_gravity.asp

    Black holes don't exist, except as an artefact of bad maths. Dark stars do though.

    Gravity is caused by matter eating ether. Everything has to eat to live you know...
    :)

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    1. Question is, though, what are those vibes if not gravity waves? And if they are gravity waves, how come they took so long to arrive if gravity travels faster than light?

      Either big physics has gone right off the rails, or this is for real, though it leaves many puzzling questions unanswered.


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    2. But an apparent refutation of Van Flandern's contention (in the article at the URL you provide) that the influence of gravity is propagated at a speed vastly exceeding that of light is provided here.

      Given van Flandern's belief in little green men, etc., I'm inclined to accept Einstein's view that changes in the gravitational field propagate at the speed of light.

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    3. Hi CS, that link just takes me back to the original article.
      TBH, I've not done the maths myself, but he's not the only one who says this... Gravity cannot logically work this way...

      Thing is - how can a *pull* propagate outwards anyway? It doesn't make sense... I.e. if the sun's sending out 'gravity particles', surely they would hit the earth and push it away. How can a particle exert a pull force? It's impossible.

      They do admit that any pull-force is problematic in mechanical terms.

      Einstein's work is flawed, and plagiarised some say. If space was curved, why would that cause gravity? Unless you already had gravity to pull you down the curve, the curve would be meaningless.
      :)

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    4. Thing is - how can a *pull* propagate outwards anyway?

      Its like a tractor beam. LOL.

      But for a better explanation you'd need to ask a physicist. But even then you'd probably not learn much. For the most part, physicists examine the relation between cause and effect mathematically. If the equations give results that correspond with observation, then the theory's "right." In contrast, the plain language explanation of the relationships observed are sometimes just fairy tales.

      How gravity waves, gravitons, whatever exert traction on massive bodies seems beyond truly intelligible common sense explanation. The same is true of magnetism.

      Einstein came up with the idea of bendy space and time because his theory of general relativity treated light waves warped by gravity as if they were straight lines on a curved plane surface, the warping of the imaginary surface then being attributed to the warping of space. Likewise, time was said to be bendy because clocks slow in a gravitational field, as calibrated with clocks outside a gravitational field.

      The idea that gravitational attraction is the result of things rolling down dips in spacetime, seems kind of daft, since what, other than gravity, which is the force to be explained, would cause a marble or anything else to roll down the dip?

      Nevertheless, gravity does pull, just as magnets pull magnetic objects. But no one, I think, has a clue why. Einstein seems to have acknowledged this when he made the comment quoted above about having to "give up, by principle, the space-time continuum."

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  2. As for,

    "How can black holes have gravity when nothing can get out because escape speed is greater than the speed of light?"

    Who says nothing can get out. Light cannot, but evidently gravity waves can!

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    1. From comments on this subject over at Quanta Magazine gravity waves are retarded by gravity, as you assumed. However, the waves detected from the black hole merger originated outside the event horizon of the colliding black holes, the energy source being the kinetic energy of the holes spinning around one another at near light speed.

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  3. The only way any pull force can work is by vacuum. I.e. it has be be a suck-force. Gravity sucks. :)
    The only reason it's a problem for physics is because they say there's no aether, so nothing to suck. If there is an aether, problem solved. Everything is simple mechanics, no spooky 'action at a distance'...
    Check this out, some good science on it that's been ignored:
    http://www.orgonelab.org/miller.htm
    I wish they'd done these experiments in a vertical direction too - it'd prove/disprove the aether rushing into the earth theory. They never did though.

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    1. Alternative physics is beyond our purview.

      But you should not suppose that (a) because you cannot visualize something that it cannot be visualized by anyone; or (b) that physics is about visualizing things. It is not. It is about determining the quantitative relationships between events that can be observed. Richard Feynman explains this well in his short book: QED.

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  4. Reminded me of something. Miles Mathis says the Michelson Morely expt shouldn't show any fringes, because of relativity:
    http://milesmathis.com/mich.html
    Maybe the best point he makes is: "If the light ray were heading at an angle upstream at velocity c in order to reach M1, as in the book, then we would need a physical explanation for that angle. Why would the central mirror reflect at an acute angle?"
    It's all good stuff to keep the Altzheimer's away... :)

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  5. "Alternative physics is beyond our purview."

    Chuckle... How can you host a blog like this, yet not prepared to look at alternatives? It's like saying "Alternative news is beyond our purview." :)

    Physics and maths are different things. Physics has to be rooted in mechanics, i.e. reality, not maths because that has no grounding, it's just a language, and can be used to create fantasies, just like any language. Although the maths must agree with the mechanics, obviously, but mechanism comes first.

    The rules of science dictate that there has to be a mechanical explanation for everything, and it has to be knowable. Science is the study of cause and effect.

    Randomness is anti-science, it precludes knowledge. QM thinks randomness is science, they're confused.

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    1. I used the term "alternative" as a polite synonym for "crackpot."

      Although the maths must agree with the mechanics, obviously, but mechanism comes first.

      Not necessarily so. Or to quote Richard Feynman, who you have not, it seems, read:

      "If you think you understand quantum mechanics, you don't understand quantum mechanics."

      or Neils Bohr:

      "If you can fathom quantum mechanics without getting dizzy, you don't get it"

      Here's Feynman in person, explaining why "it's not like a ball-bearing on a spring"!

      https://www.youtube.com/watch?v=A7GlK9FqzgE

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