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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.
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.
I guess insults are part of science now? Or is this just someone with an expensive speech comm degree writing about science who has been radicalized to hate anyone who disagrees with current theory. As another poster suggested go test the hypothesis and let us know without resorting to insults. If you can manage that.
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.
Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
Science needs evidence. Evidence that can be obtained by repeatable and independent experiments. If you can't provide that, you run into problems in science. Then it's philosophy at best.
Rupert Sheldrake hasn't done any real science in 30 years.
Il n'y a pas de Planet B.
So, what you are saying is - "Why can't you explain this to me using a car example?".
Second class citizen of the New Gilded Age
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.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
This has been explained countless times.
Vectors aren't additive that way.
http://hyperphysics.phy-astr.g...
http://hyperphysics.phy-astr.g...
https://opentextbc.ca/physicst...
In a nutshell, relative velocity alters space and time. It's the Lorenz Contraction. This throws in the extra term into the equation.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
He's a biologist. I don't get my astrophysics from biologists any more than I get my biology from astrophysicists.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
The point is, someone is proposing a method of using a in-construction tool to test this point, as their "card on the table" in the competition for observing time on the scope when it achieves first light. Or, considering it'll be a zenithal scope, whose viewing schedules are dictated by the rotation of the Earth, they'll be bidding for time to observe (and get spectra of) the supernovae that get caught by the LSST, using other steerable scopes that can accumulate the tens of hours of observation needed to get a spectrum of adequate signal-to-noise level.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
....and Dr. Andrew Wakefield was an actual doctor, until he started falsifying research results in his bid to con the UK government out of money by selling an "alternative" vaccination drug. I guess when people start caring more about making money than honesty and integrity, shit goes sideways: hence - conman.
You're sucking the dick of his dogma,while complaining about people preferring reality to bullshit. Grow the fuck up, use that wilted brain you supposedly have in your head, and clean the bullshit out of your eyes.
Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
Oh yes, ""Zur Elektrodynamik bewegter KÃrper" (in English, "On the Electrodynamics of Moving Bodies", in which he refers extensively to Maxwell's work and the asymmetries "which do not appear to be inherent in the phenomena" (Perrett and Jeffery's translation of 1923). Einstein cited his sources perfectly adequately in the form of the time, even if subsequent writers haven't been so careful in their commentary on his work.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
I am kind of curious how determining if physical laws are constant over time or variable became the province of "Wingnuts and kooks".
Sounds like Rock Doctor has issues.
The guy who thinks that science is wrong because it can't explain absolutely everything? And quite coincidentally he has a hypothesis of everything of his own? I don't think he really understands what science is about.
Of course that doesn't mean everything he says must automatically be wrong. So please make precise references that illustrate your point and don't expect others to do that job for you.
The problem is having faith in the result before the experiment is done. There's been argument over the years about if physical constants are constant and if physical laws have been consistent over time. Anyone who asserts they are or aren't without experimental data to back up their position is equally bad, and not actually using the scientific method or in any way practicing science.