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A physicist is using a theory he advanced to explain how EmDrive could work to explain how dwarf galaxies can be held together without the requirement of dark matter:
British physicist Dr Mike McCulloch, who previously used quantised inertia to explain how the controversial electromagnetic space propulsion technology EmDrive works, says that he has new evidence showing his theory can also explain galaxy rotation, which is one of physics' biggest mysteries. McCulloch, a lecturer in geomatics at Plymouth University's school of marine science and engineering, says he now has even more evidence that his "new physics theory" about quantised inertia works, and that it makes it possible to explain why galaxies are not ripped apart without using theory of dark matter.
[...] There are 20 dwarf galaxies in existence from Segue-1 (the smallest) to Canes Venatici-1 (the largest), and dark matter is only meant to work by spreading out across a wide distance, but it is still used to explain dwarf galaxies, even though this requires dark matter to be concentrated within these systems, which is implausible. Instead, McCulloch asserts that quantised inertia can be used to explain how galaxies rotate without using dark matter, and he has written a paper that has been accepted by the bi-monthly peer reviewed journal Astrophysics and Space Science.
Reprint of the IBT link here.
From the abstract of Low-acceleration dwarf galaxies as tests of quantised inertia (DOI not yet published):
Dwarf satellite galaxies of the Milky Way appear to be gravitationally bound, but their stars' orbital motion seems too fast to allow this given their visible mass. This is akin to the larger-scale galaxy rotation problem. In this paper, a modification of inertia called quantised inertia or MiHsC (Modied inertia due to a Hubble-scale Casimir effect) which correctly predicts larger galaxy rotations without dark matter is tested on eleven dwarf satellite galaxies of the Milky Way, for which mass and velocity data are available. Quantised inertia slightly outperforms MoND (Modied Newtonian Dynamics) in predicting the velocity dispersion of these systems, and has the fundamental advantage over MoND that it does not need an adjustable parameter.
Previously: Study Casts Doubt on Cosmic Acceleration and Dark Energy
Dark Matter Beats its Latest Challenge
Emergent Gravity and the Dark Universe
Space Race 2.0: China May Already be Testing an EmDrive in Orbit
Milky Way is Not Only Being Pulled—It's Also "Pushed" by a Void
(Score: 0, Disagree) by Anonymous Coward on Wednesday February 15 2017, @02:51PM
If it turns out that the Em drive actually doesn't work (recall that the only measured results are, shall we say, less than convincing), what does that say about McCullough's model?
(Score: 1, Interesting) by Anonymous Coward on Wednesday February 15 2017, @04:08PM
They measured a rotational performance of:
What is special about this ~833,333.3 m/s? Multiply by 360 to get 1.000692*c. In other words, c/360 m/s is well within the uncertainty.
(Score: 2) by VLM on Wednesday February 15 2017, @05:51PM
You missed the last line of the abstract
Quantised inertia slightly outperforms MoND (Modied Newtonian Dynamics) in predicting the velocity dispersion of these systems, and has the fundamental advantage over MoND that it does not need an adjustable parameter.
Measured results are not going to change just because a rocket engine test failed.
What would have to change is the guys explanation for why something that observably works well for galaxies doesn't work so well at a smaller scale like rocket engines. Or a classic favorite of theorists for centuries, the observations (of the galaxy, or maybe the engine, or both) had a larger than predicted error.
(Score: 0) by Anonymous Coward on Wednesday February 15 2017, @05:57PM
Yes, NASA and many others are in a big conspiracy to make you think ... umm.. something? I'll take NASAs word over a random internet troll :P
(Score: 2) by HiThere on Wednesday February 15 2017, @08:21PM
Wellllll.....It's not exactly NASA, it's a subcontractor or some such. It still seems reasonably reasonable to prefer to believe them. Just not quite so much so.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 0) by Anonymous Coward on Wednesday February 15 2017, @11:13PM
My comment was too hasty, I missed the first word "if" and mixed it with the 2nd "it" so egg on my face!
(Score: 2, Informative) by Arik on Wednesday February 15 2017, @06:35PM
If you work out the math you could in theory, by using the entire US Electrical generation capacity to power a giant cluster of these things, lift about 1000 people off the ground using it. And make them hover.
So yeah it's not very impressive, but it does seem like it may demonstrate an effect, however weak, that isn't explained by standard physics models. This could be the explanation. But if the EM drive turns out to be a chimera instead of just unimpressive, he'd certainly need to explain his mistake.
If laughter is the best medicine, who are the best doctors?
(Score: 2) by takyon on Wednesday February 15 2017, @06:49PM
Coming up with a theory that explains EmDrive could go a long way towards boosting that low thrust output. Assuming the EmDrive effect is real, it's not going to get improved very fast if nobody knows how it works. Compare it to the understanding of nuclear fission and the Chicago Pile experiment which is sometimes brought up by EmDrive optimists.
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(Score: 3, Insightful) by r1348 on Wednesday February 15 2017, @08:25PM
Once the theory is sound, engineering can kick in.
(Score: 2) by sjames on Wednesday February 15 2017, @07:08PM
So far, tests suggest that it DOES work, but that the effect is small. Perhaps it will always be small, or perhaps (unsurprisingly) we just don't know how to build a decent EmDrive yet.
There are many permutations for how quantized inertia, EmDrive, and various theories of galactic rotation (as well as inflation, expansion of the universe, etc) might work out. But so far, we don't know enough to design an unambiguous make or break experiment.