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Star's Strange Path Around Black Hole Proves Einstein Right -- Again (science.org) 61

Posted by msmash from the closer-look dept.
Albert Einstein's theory of general relativity has aced another test. From a report: Following nearly 3 decades of monitoring, researchers have detected a subtle shift in the orbit of the closest known star to the supermassive black hole at the center of the Milky Way -- and the movement matches Einstein's theory precisely. The star, known as S2, follows an elliptical 16-year orbit. It made a close approach -- within 20 billion kilometers -- to our black hole, Sagittarius A*, last year. If Isaac Newton's classic description of gravity holds true, S2 should then continue along exactly the same path through space as on its previous orbit. But it didn't. Instead, it followed a slightly diverging path, the axis of its ellipse shifting slightly, a team using the European Southern Observatory's Very Large Telescope reports today in Astronomy & Astrophysics. The phenomenon, known as Schwarzschild precession, would, in time, cause S2 to trace out a spirographlike flower pattern in space -- as general relativity predicts.
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Star's Strange Path Around Black Hole Proves Einstein Right -- Again More

Star's Strange Path Around Black Hole Proves Einstein Right -- Again

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  • It's the Mercury orbit (Score:5, Informative)

    by Sique ( 173459 ) on Tuesday October 19, 2021 @10:05AM (#61906491) Homepage
    One of the big scientific questions Albert Einstein tried to tackle with his General Relativity was the precession of the Mercury orbit around the Sun. S2 does the same around Sagittarius A*, just with 4.3 Mio times the magnification.
    • Also gravity is not necessarily a "force" as it is a consequence of the curvature of space-time due to mass.
      • It's a fictitious, or virtual, or apparent force, similar to how centripetal force works. It is real enough in a given reference frame, which is why we experience near constant acceleration on the surface of Earth. So while it's not a force per se, it can be treated as one for most purposes. Newtonian gravitational theory is "good enough" for most orbital mechanics computations, and vastly simpler than solving Einstein's field equations for space flights and such. You need Einstein for things like the p

        • Re:It's the Mercury orbit (Score:5, Informative)

          by UnknowingFool ( 672806 ) on Tuesday October 19, 2021 @12:06PM (#61906891)
          The main point of distinction in that conceptually Newtonian mechanics describes gravity as a force between two objects as some sort of invisible string. Einstein's model gives far more accuracy to how gravity really works. For example if the sun were to disappear what would happen to the Earth? Newtonian: the Earth would fly off instantly in the direction it was headed when the sun disappeared. Einstein: the Earth would fly off after 8 minutes because gravity like everything else cannot be faster than the speed of light.

          • Re: (Score:1)

            by Anonymous Coward
            We must fund an experiment to test this!

          • gravity...cannot be faster than the speed of light.

            I may be wrong but isn't quantum entanglement instantaneous and theoretically faster than the speed of light? Assuming that's true; is it possible that gravity could be instantaneous as well? Personally, I tend to think you are correct but I am playing devil's advocate to sate my own curiosity.

            • Yes quantum entanglement proposes a paradox; however gravity has been shown to obey the limits of the speed of light. The LIGO detectors are based on the assumption that gravity waves take time to travel through space.
              • Thank you for pointing me in the right direction. I wish more people would engage this way. It makes it much easier for me to learn.

        • You could say the same for inertia as well. It's a virtual force realized in a 4D environment.

    • This diagram give a good idea of the relative distances involved. Mercury's orbit would be too small to show.

      https://en.wikipedia.org/wiki/... [wikipedia.org]

  • Tesla, the relativity skeptic (Score:5, Interesting)

    by Desert Tripper ( 1166529 ) on Tuesday October 19, 2021 @10:35AM (#61906581)
    Tesla was right on many things, but relativity theory was not one of them: "Moreover, Tesla completely rejected the theory of relativity. He insisted that mass and energy were not equivalent and told the New York Times in 1935 that "Einstein's relativity work is a magnificent mathematical garb which fascinates, dazzles and makes people blind to the underlying errors. The theory is like a beggar clothed in purple whom ignorant people take for a king..." -- Forbes Magazine, 9/26/11... Einstein 1, Tesla 0

    • Re: (Score:1, Funny)

      by Anonymous Coward

      Did you short Tesla stock or something? Who hurt you?

    • More like Einstein 1000+ at this point

    • Re: (Score:1)

      by danda ( 11343 )

      Tesla will be vindicated.

    • Tesla was right on many things, but relativity theory was not one of them: Einstein 1, Tesla 0

      They were just ignorant to each other's unique perspective of how the Universe works.

      The Universe can operate in both mechanisms; we have zero understanding how it actually works in the first place -- pretending to gleam a slightly repeatable event and think EUREKA! is the height of arrogance.

      • They were just ignorant to each other's unique perspective of how the Universe works.

        Ummmm. No.

        Einstein was one of the relatively (sorry) small number of physicists who took Maxwell's mathematical theory of electromagnetism seriously, and in particular the derivation in that that the speed of light (in a vacuum) was the ratio of two properties of that vacuum, both of which were constants ; therefore, the speed of light is also a constant. From that he developed a number of consequences, entirely dependent

        • Perspectives are per user. Blame it on whatever makes you feel better.

        • Re: (Score:2)

          by wv5k ( 771543 )
          I apologize for the lack of Mod Points today. I don't think I've read a more brilliant rebuttal, and one that went a bit further than it had to. Huzzah!
          • I'll take the mod points as read. But thanks for the comment. I do actually try to contribute usefully, which is not a modern concept.

  • That's about the distance to the voyager 2 space probe. Gravity (space-time) must be all kinds of fucked up around there. It can't possibly be pretty there.

    • From the paper
      On May 19, 2018 (2018.38), S2 passed pericentre at 120 AU (1400RS) with an orbital speed of 7700 km/s-1
      I did some terrible math (Cause I don't understand most of the words in that paper) and came up with a pull of 1.71m/s^2 at that distance; so that's probably not close enough to get any extreme space time effects, but that can't be good for the star.
      • I did some terrible math (Cause I don't understand most of the words in that paper) and came up with a pull of 1.71m/s^2 at that distance; so that's probably not close enough to get any extreme space time effects, but that can't be good for the star.

        Eh, don't worry about it. Whatever happens, it will buff right out.

      • a pull of 1.71m/s^2 at that distance; [...] but that can't be good for the star.

        A touch over one-6th of a g - it's not going to be like driving into a brick wall, but it's going to be a death of a thousand cuts [wikipedia.org]. as the matter stripped from the star's "solar wind" hit the accretion disc and brighten it, inflating the stars "solar wind", leading to more material in the accretion disc, heating the "solar wind" even more on the next pass.

        Yeah, that one is off the "life insurance policy" cold-calling list. It'

  • Some books you can read:

    * Space, Time, And Matter and the Falsity of Einstein's Theory of Relativity.
    * The Dynamic Ether of Cosmic Space: Correcting a Major Error in Modern Science
    * Disruptive: Rewriting the rules of Physics
    * The big bang never happened
    * Bye Bye big bang, hello reality
    * Einstein and the Ether

    Quotes From: Dayton Miller's Ether-Drift [orgonelab.org]
    Experiments: A Fresh Look

    "The effect [of ether-drift] has persisted throughout. After considering all the possible sources of error, there always remained a posit

  • Stop saying prove... (Score:5, Insightful)

    by Shaiku ( 1045292 ) on Tuesday October 19, 2021 @12:37PM (#61906985)

    Instead of "proves Einstein right" how about "behaves according to Einstein's predictions."

    It's frustrating when people misrepresent the scientific process and critical thought with statements like "It was just a theory but now you've proved it!" Ugh.

    • Thank you this kind of headline annoys me every time I see it. Imagine if in every article about DNA was headlined "proves Watson and Crick right about DNA --Again"

    • Re: (Score:1)

      by danda ( 11343 )

      yes, to me this is just evidence of how science is taught in the schools anymore. Theories are being presented as settled fact, and alternative theories are not presented at all, or given very short shrift. Students are taught to digest and accept (even if it doesn't make sense!) rather than to think critically, question, and test new explanations.

      Yesterday's accepting students are today's journalists and slashdot editors.

      There are various theories that can predict the same movements as relativity, some t

      • Yeah outrageous that they are taught about theories with immense amounts of confirming data, and exclude theories with no support at all. Amirite?

      • yes, to me this is just evidence of how science is taught in the schools anymore.

        At best (or worst) this shows a problem with how science is taught in the schools you are familiar with. Strangely, in other places (individual schools, counties, countries, or continents), science teaching is done differently. For example, I was taught physics on a syllabus produced in the early 1970s [nuffieldfoundation.org] where pupils derived relationships between parameters and behaviours on the lab bench themselves, and derived laws from those

        • Re: (Score:1)

          by danda ( 11343 )

          The double-slit experiment is typically used as an argument for Quantum mechanics, not relativity.

          Regardless, I recommend you read the book "Disruptive: re-writing the rules of physics", starting at page 256, which provides another explanation for what you witnessed that is compatible with classical mechanics and newtons laws, as well as something called "Modern Mechanics" by Steven Bryant.

          If you are open-minded and a critical thinker, you should be open to new ideas and alternative explanations for nature'

        • Re: (Score:1)

          by danda ( 11343 )

          ps, your intuition not accepting it is actually your common sense and "true self" telling you that the explanation you've been told sounds like BS. You should listen to it, and seek out a better explanation, or invent one yourself. Instead, most students ignore their true self, embrace their insecurity which whispers that the teachers and scientists are smarter, therefore it must be true, even if non-nonsensical. Then these people teach others, and ever the cycle continues.

  • ... and for the folks that have been tracking/proving his theory. For me.. reading only that one paragraph hurts my head.
  • FTFS:

    If Isaac Newton's classic description of gravity holds true, S2 should then continue along exactly the same path through space as on its previous orbit.

    This would only be true if (and only if) both objects - the visible star and the hard-to-see black hole were the only objects in the entire universe (untrue - we're here!) and neither could shed any material onto a course different to the rest of the body (we don't know for the BH, but Hawking's radiation suggests not ; we do know that stars shed a sola

  • How long before S2 meets the event horizon?

    20B kilometers is roughly 3.5 times the average Sun-Pluto distance.
    Considering that SagA* is estimated at ~4 million solar masses, the yank on S2 must be extraordinary at perigee.

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