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Can We Test the Speed of Light Using 'Lensing' from Supernovae? (arxiv.org)

Long-time Slashdot reader RockDoctor writes: One of the key assumptions of Relativity — both Special and General — is that the speed of light is a constant in all non-accelerating reference frames. As a key assumption, it is also one of the things that gets the kooks, wingnuts and fanatics all riled up, because they have proven that it's wrong, though those pesky scientists refuse to listen to their spittle-flecked presentations.

Back in the real world, real scientists also wonder if the assumption is justified, then try to work out how to test it. One idea for performing this test has just been published — that of using the gravitational lensing of distant supernovae to try to interrogate the speed of light in the distant past.

When a (relatively) nearby galaxy lenses a (relatively) distant galaxy, it is common for multiple images to be formed. If a supernova occurs in the distant galaxy, then supernova images will be seen in the different images, but typically at different times (on Earth) because the light paths from different images are of different lengths, and were of different lengths in the past.

The Chinese-Polish team of authors have studied the possibilities of making such observations and suggest that the LSST (Large Synoptic Survey Telescope, "a wide-field survey reflecting telescope with an 8.4-meter primary mirror, currently under construction, that will photograph the entire available sky every few nights") should detect several thousand gravitationally-lensed distant quasars, and so yield around 50 gravitationally-lensed distant supernovas per year. This is estimated to "produce robust constraints on the speed of light at the level of delta-c/c;= 0.005" (half a percent) in a decade of operations.

Which will shut the wingnuts, lunatics and kooks up. Not.At.All.

3 of 112 comments (clear)

  1. Re:Spittle??? by meglon · · Score: 4, Informative

    I can't tell if you're being sarcastic, or if you're really so stupid as to think Sheldrake is anything more than a psuedo science conman.

    https://newrepublic.com/articl...

    He's as much of a conman as those dipshits who spout the electric universe bullshit... which i'm sure we'll be seeing on this thread in no time.

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    Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
  2. Re:Spittle??? by Zontar+The+Mindless · · Score: 4, Informative
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    Il n'y a pas de Planet B.
  3. Re: Wait, in all *NON*-accelerating reference fram by jd · · Score: 3, Informative

    The speed of light is a constant, time and space change under the Lorenz contraction in a way that keep light fixed.

    (Technically, light only happens to travel at C in a perfect vacuum. C is not otherwise related to light.)

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