The idea of inertia is that in a vacuum, where there is no friction, objects move along in a straight line at constant speed until you push on them. This tendency was first isolated by Galileo, who rolled balls down inclined planes (balls feel less friction). This tendency, inertia, has always been assumed but never explained.
Meanwhile physics has moved towards a study of information, and it has been realised in the past few decades that when you accelerate something, say, to the right, information from far to the left can never catch up to it, this means there is an information-boundary or 'horizon' to its left which is like a black hole event horizon (it is called a Rindler horizon). A kind of Hawking radiation comes off this horizon, which is called Unruh radiation (it was proposed by Bill Unruh) and is seen as background radiation, but is seen only by the accelerated object.
The new prediction from the model then is that objects with very low acceleration lose inertial mass in a new wa
It has been shown that cone-shaped cavities with microwaves resonating within them move slightly towards their narrow ends (the emdrive). There is no accepted explanation for this. Here it is shown that this effect can be predicted by assuming that the inertial mass of the photons in the cavity is caused by Unruh radiation whose wavelengths must fit exactly within the cavity, using a theory already applied with some success to astrophysical anomalies where the cavity is the Hubble volume. For the emdrive this means that more Unruh waves are "allowed" at the wide end, leading to a greater inertial mass for the photons there. The gain of inertia of the photons when they move from the narrow to the wide end, and the conservation of momentum, predicts that the cavity must then move towards the narrow end, as observed. This model predicts the available observations quite well, although the observational uncertainties are not well known.
Three independent experiments have shown that when microwaves resonate within an asymmetric cavity an anomalous force is generated pushing the cavity towards its narrow end.
This force can be predicted to some extent using a new model for inertia that has been applied quite successfully to predict galaxy rotation and cosmic acceleration, and which assumes in this case that the inertial mass of photons is caused by Unruh radiation and these have to fit exactly between the cavity walls so that the inertial mass is greater at the wide end of the cavity. To conserve momentum the cavity is predicted to move towards its narrow end, as seen.
This model predicts the published EmDrive results fairly well with a very simple formula and suggests that the thrust can be increased by increasing the input power, Q factor, or by increasing the degree of taper in the cavity or using a dielectric.
SOURCES - Physics from the Edge, Progress in Physics
(For those not in the know, modified inertia theories are somewhat controversial as an alternative explanation for dark matter. Still a lot less controversial than the EM Drive and its experimental results.)
McCulloch's idea is strange because the inertial mass of photons is zero in vacuum. Well, whatever; let's assume he meant to define m = E/c² instead; since E = pc, that would actually make his starting equations tautologically true. Then offhand, the biggest problem with this "mass is affected by Unruh radiation through a Hubble-scale Casimir effect" idea, which is interestingly vaguely similar to Sonny's (except not based numerology of the Planck force), is that we've seen exactly the same thing before regarding the Pioneer anomaly [arXiv:astro-ph/0612599], where it actually overestimated the anomalous acceleration... which means that it's just plain falsified, because to statistical significance, the anomalous acceleration is the result of thermal radiation.
So ironically enough, the fact that the acceleration in the Pioneer probes is no longer anomalous now provides falsification to McCulloch's modified inertia idea. This is very much controversial and outright far-fringe.
I think you may be confusing this is Milgrom's 'modified inertia', which despite being called the same, is a very different thing, being a path-dependent offshoot of MOND. As far as I know, it never went much of anywhere. However, MOND itself does have a relativistic formulation, so it is indeed far less controversial, though the main problem with things like TeVeS is that they're worse that the 'disease' they're trying to cure. But that's a wholly different story.
Yeah, when I was reading up on the author's introduction to MiHsC, I started getting really annoyed about a lack of a source of momentum for photons, which his explanation for the EM Drive banks on. If he'd suggested the walls reacting to the bouncing photons in an asymmetric way, there'd be a ready mechanism for his theory of inertia to create interesting results. As is, it's just bizarre.
Further reading in the author's blog has revealed other oddities, like his claim that he can replicate Podkletnov's superconductor gravity shield (blatant crank physics) and Tajmar's gravitomagnetism result. As far as I can tell, he provides a source of inertia, but doesn't address the equivalence principle or an alternative to General Relativity. The latter is especially bizarre as MiHsC is essentially a set of correction terms to GR, but introduces breaks from relativity in the form of FTL being possible (via minimum acceleration) and a complete lack of anything resembling equivalence. It really needs a whole new treatment of relativity, but what's there is...lacking.
I wasn't aware until now that the Pioneer anomaly had falsified MiHsC. Amusingly, the author has a rant about how his model is totally simpler and how a 2000 element finite element model is overly complex and can't be trusted. You know, because overturning one of the fundamentals of physics is simpler than modelling thermodynamics using industry standard practices.
I did, actually, but I was grabbing the "quantized inertia" thing straight from title because I hadn't refreshed myself on which alternate model of cosmology it was yet.
Heh. The last bit explains the first: the objective is to find an equation that fits the data, not find a physically coherent mechanism. That's why McCulloch's idea is 'simpler' than a 2000 element thermodynamical model. It's pretty typical behavior among cranks. Hell, McCulloch himself is probably aware of this at least on some subconscious level, since he explicitly states that photons aren't supposed to work that way but proceeds regardless.
I've never heard of Tajmar, but looking him up just now, he's a pretty interesting contrast to McCulloch.
Tajmar had an idea that the Cooper pair mass anomaly in spinning superconductors can be explained by a gravitomagnetic field. The gravitomagnetic field should be thirty-something orders of magnitude weaker than the magnetic field, so this part doesn't make any sense to me, but I'm not going to try to sort it out right now, so let's just roll with it... Tajmar did an experiment in 2006 that supported his theory. At STAIF 2006, he repudiated Podkletnov. In 2007, an independent experiment failed to replicate his results [pdf]. Finally, another experimental test by Tajmar (2011) was a hundred times more sensitive than any before it and yielded no result, contradicting his own earlier experiments.
To summarize, Tajmar had a somewhat far-out idea and proceeded to test it pretty thoroughly. Tajmar: +3. McCulloch: -eleventybillion. My favorite part:
"It's obviously very difficult to actually [replicate experiments]. The replication aspect in experimental physics—that's a very, very important aspect." — Martin Tajmar at STAIF 2006
Some people in this thread could also learn a bit from this man.
Yeah, but it's the complete lack of address about the equivalence principle that prevents it from being considered to be some correction to GTR. Even with weak equivalence, test particles fall the same way in a gravitational field, regardless of mass or composition, and weak equivalence actually has very impressive experimental tests (to about 10-13). So messing with mass shouldn't do anything at all to the Pioneer probes as far as gravity is concerned, for any metric theory of gravity (not just GTR).
Mind, that's not to say that McCulloch's idea absolutely can't be the Newtonian limit of some properly relativistic theory of gravity, but that in order to fit with any metric theory of gravity whatsoever, much less be a correction to one, the its mass interpretation would need to be jetissoned and its effect mimicked by some other means. So the idea was pretty much destined to be a controversial footnote from its inception even if the Pioneer anomaly wasn't resolved, but all that's moot at this point, since it predicts wrong things anyway.
It's behind a paywall, but apparently a third party has a paper in the process of peer review after conducting near-space grade hard vacuum tests with nearly identical results to the Eagleworks guys.
By:
Martin Tajmar, Technical University of Dresden
From Abstract:
Our measurements reveal thrusts as expected from previous claims after carefully studying thermal and electromagnetic interferences. For the first time, measurements were also performed in high vacuum. Due to a low Q factor of <50, we observed thrusts of +/-20 µN.
From what some people who could get behind the paywall report, the guys eliminated quite a few experiment error explanations again, to include a few that the Eagleworks guys haven't considered. Additionally, we're getting a report from Eagleworks on Monday (supposedly), which seems to be that their upscaled test worked, but invalidated their working theories on the device.
More importantly, it apparently matches the thrust predictions for the size of the device according to the rough equations developed by Eagleworks, and might be a little more powerful.
Tajmar Experimental results
Cavity Length(m) = 0.0686
Big Diameter(m) = 0.0541
Small Diameter(m) = 0.0385
Dielectric = None
Frequency = 2.44Ghz
Input Power = 700w (output of magnetron)
Pressure = 4×10-6
Q = 20.3 (seems like this was measured and calculated after they finished all reported testing)
Force (mN) = 0.02
This information and more is on the eagleworks forum now.
According to 'Tron' on the eagleworks forum: McCulloch's formula F = 6PQL/c * ( 1/(L+4wb) - 1/(L+4ws) ) predicts unless I'm mistaken 0,019 mN for those numbers. I think it's remarkable.
Maybe? This guy is trying to disprove the drive, or at least figure out where Eagleworks is screwing up, but he's basically matching result for result so far and is generating that nice third-party confirmation everyone wanted.
To be fair when you hear someone claiming their experiment has "Broken the laws of physics as we know them." the default assumption is "experimental error." since that is far more likely.
It's only when you start getting multiple experimental confirmations which eliminate more and more possible causes that it actually starts to look more credible.
These tests are faulty, they did something wrong and these 'results' tell us nothing about the actual operating principle.
People never disputed that this thing produces thrust. What people are skeptical about is the 'reactionless' part of reactionless thrust. If you somehow violate momentum conservation (as some people claim this drive does) you break gauge symmetry and everything ever breaks down. Even seemingly unrelated fields like thermodynamics would be completely wrong. Infinite energy exploits everywhere, laws depending on the position of the observer, cats and dogs living together.
Considering that the last 2000 years of science has given us such wonderful inventions as the computer I'm typing this on, I am a bit skeptical that everything ever is wrong.
These tests are faulty, they did something wrong and these 'results' tell us nothing about the actual operating principle.
People never disputed that this thing produces thrust. What people are skeptical about is the 'reactionless' part of reactionless thrust. If you somehow violate momentum conservation (as some people claim this drive does) you break gauge symmetry and everything ever breaks down. Even seemingly unrelated fields like thermodynamics would be completely wrong. Infinite energy exploits everywhere, laws depending on the position of the observer, cats and dogs living together.
Considering that the last 2000 years of science has given us such wonderful inventions as the computer I'm typing this on, I am a bit skeptical that everything ever is wrong.
And most people think we're missing the reaction. For fucks sake, just look back in this thread, and I and others have put out theory after theory of what in the hell this thing is interacting with. All this thing working means is that WE MISSED SOMETHING. And that's good. Just because we MISSED something doesn't mean that all the rest suddenly stops working. Reality doesn't crash just because we finally discovered a part that we never noticed before.
It's not like the standard model even works all that great. The very existence of quantum physics and the fact that Quantum Physics doesn't work at all with macro-scale stuff means that it has giant fucking holes in it that we've needed to patch for a while.
Now, though, we might actually have the first glimpse of what is holding the two together. Have an open mind, instead of dogmatically screaming that everything new is a lie.
If a guy who deliberately set out to prove it wrong--and uniquely qualified as maybe one of a select handful of people on the planet EVER who actually could say one way or another--can only say 'I can't, it works', then there is something there beyond a shadow of a doubt. Now is not the time to go around panicking. Now is the time to go 'hey, Bob, let's poke this thing until we figure it out'.
And most people think we're missing the reaction. For fucks sake, just look back in this thread, and I and others have put out theory after theory of what in the hell this thing is interacting with. All this thing working means is that WE MISSED SOMETHING. And that's good. Just because we MISSED something doesn't mean that all the rest suddenly stops working. Reality doesn't crash just because we finally discovered a part that we never noticed before.
It's not like the standard model even works all that great. The very existence of quantum physics and the fact that Quantum Physics doesn't work at all with macro-scale stuff means that it has giant fucking holes in it that we've needed to patch for a while.
Now, though, we might actually have the first glimpse of what is holding the two together. Have an open mind, instead of dogmatically screaming that everything new is a lie.
If a guy who deliberately set out to prove it wrong--and uniquely qualified as maybe one of a select handful of people on the planet EVER who actually could say one way or another--can only say 'I can't, it works', then there is something there beyond a shadow of a doubt. Now is not the time to go around panicking. Now is the time to go 'hey, Bob, let's poke this thing until we figure it out'.
Science is about Dogmatic Facts that can't be proven wrong by new discoveries- things that don't fit into the models we have set up by the gods known as Einstein and newton must -obviously- be wrong.
Science is about Dogmatic Facts that can't be proven wrong by new discoveries- things that don't fit into the models we have set up by the gods known as Einstein and newton must -obviously- be wrong.
At least now we can riposte with the 'a scientist more qualified than you says its not bullshit' card. He's worked on narrowing down a lot of strange edge-case magnetic/superconductive interactions along with narrowing down a lot of other edge-case instrument error eliminations, like one particularly interesting interaction between super-cooled gyroscopes and liquid helium.
Given how annoyingly conservative some sectors of the space establishment and scientific community can be, you'd probably be celebrating on your death bed.
Nah. Vorpal's one of those "If the results don't fit what I predicted in my hypothesis, then the results are obviously wrong and should be abandoned, and the experiment modified till I get the results I predicted" types.
At least now we can riposte with the 'a scientist more qualified than you says its not bullshit' card. He's worked on narrowing down a lot of strange edge-case magnetic/superconductive interactions along with narrowing down a lot of other edge-case instrument error eliminations, like one particularly interesting interaction between super-cooled gyroscopes and liquid helium.
Exactly. This guy narrowed things down. He didn't find a source.
To give an analogy. Say I measure the spectrum of the moon and conclude that the lunar surface does not contain Uranium, Rubidium or Krypton. Does that mean you can conclude the moon is made of cheese? According to your logic this is a sensible conclusion.
Science is about Dogmatic Facts that can't be proven wrong by new discoveries- things that don't fit into the models we have set up by the gods known as Einstein and newton must -obviously- be wrong.
oh quit being such a big baby "Waaah the mean people are telling me that this can't possibly be totally right because it would completely overturn everything the past 2000 years of science has told us about how the universe works as we understand it and violates the second law of thermodynamics and means you can beat fucking ENTROPY".
Good god every time someone points out how this isn't nearly enough evidence to prove its a TRUE reactionless drive or that the people trying to explain it are using pure made up bullshit you just whine whine fucking whine.
Exactly. This guy narrowed things down. He didn't find a source.
To give an analogy. Say I measure the spectrum of the moon and conclude that the lunar surface does not contain Uranium, Rubidium or Krypton. Does that mean you can conclude the moon is made of cheese? According to your logic this is a sensible conclusion.
Except what you're saying is "We don't know -how- this thing works, so it obviously doesn't work because the theories that haven't be disproven don't fit the standard model.."
oh quit being such a big baby "Waaah the mean people are telling me that this can't possibly be totally right because it would completely overturn everything the past 2000 years of science has told us about how the universe works as we understand it and violates the second law of thermodynamics and means you can beat fucking ENTROPY".
That's not how fucking science works you goddamned idiot. If you observe something in an experiment that proves previous theoreis wrong, and then other experiments match the results you got, You don't go "Well this says that what we thought we knew was wrong, and that just can't be true!"
