In 2011 I was invited up to St Andrews University to talk about MiHsC (The title of my talk: Can inertia be modified electromagnetically?). Their physics department has a superb reputation so I was a little nervous. I met some of the academics and sat down to have lunch with them and one of them asked incisively: "If MiHsC is true then why don't we see the inertial mass of something in a metal box reduce?". Well, at the time I nearly choked on my tuna sandwich, but in fact this was one of the first questions I asked myself in the early days, and, when I got my voice back, I explained that for the accelerations of objects we are familiar with, the Unruh waves are extremely long. For example, an object with an acceleration of 9.8 m/s^2 will see Unruh waves 7x10^16 m long (a few light years) and Faraday cages do not affect such long EM waves (submarines can receive long EM waves). Also, as some of the lecturers there helpfully pointed out: Unruh waves are not solely EM waves, they're waves in all the fields.
How about light in a box though? If you have photons in a box whose inner sides are mirrored, then they do contribute an inertial mass to the box because if you move the box one way, then the photons bash into the mirror on the backwards side and so contribute to the inertia that opposes the box's motion. So light or photons in a box, have inertial mass. The interesting thing about the photons in a metal box is their fast speed, so that the mirrors are forcing them to accelerate rapidly backwards and forwards. That means the Unruh waves associated with their inertia are now of a similar wavelength to the box's size and they can be damped by its walls, at least their EM component. So MiHsC predicts a loss of inertial mass for the light in the metal box, just the same as it predicts a much smaller loss of inertia for objects inside the Hubble volume.
Now what if the box is a cone? (EMdrive) The photons are resonating within it so the Unruh waves they see are of a similar size to the cone and typically fewer Unruh waves will fit or 'be allowed' at the narrow end of the box than at the wide end. One way of thinking about this is that the photons going from the narrow to wide end gain inertial mass in a new MiHsCian way. This turns out to be a bit like the old rocket method of blasting hot gas out of the wide end, but now we are blasting 'virtual' mass. To conserve momentum (mass*velocity) the whole system has to move the other way. Hence the typical motion of the Emdrive towards its narrow end. MiHsC predicts the results quite well without any tuning parameters, see earlier blogs or my paper on MiHsC and the Emdrive here (an introduction to MiHsC is here).
Note that, if the EM waves' frequency is tuned so that the Unruh waves fit better within the narrow end, then the Emdrive might actually move the other way, and it would be interesting to know whether this was the case for the recent NASA experiment where it did actually move the other way. I'm now working on a second paper, that takes into account individual Unruh waves, to be submitted..
Reference
McCulloch, M.E., 2015. Can the Emdrive be explained by quantised inertia? Progress in Physics, Vol. 11, 1, 78-80 (Pdf).
8 comments:
An article on the EM drive appears somewhere on NSF tomorrow (Wednesday, 4-29). Draft was written by 'Mulletron,' rewritten by Doctor Rodal, and made...readable...by Chris Bergin and company.
Doctor Rodal did mention that a great deal of the research done in the EM Drive threads is covered in a superficial way. Primary focus is on the Eagleworks experiments. It would take a book to do full justice to the material covered in that thread, and the dang thing would be outdated within minutes of being published.
OOT but might be worth reading. http://www.sciencehook.com/hook.php?entryID=407 Change in G constant no so constant...
http://www.nasaspaceflight.com/2015/04/evaluating-nasas-futuristic-em-drive/#.VUE4ptUjwiw.google_plusone_share
Another article about NASA EM Drive.
Mike, your work was mentioned on a reddit thread about the Em-drive:
http://www.reddit.com/r/Futurology/comments/34cq1b/the_facts_as_we_currently_know_them_about_the/cqto41k
One of the responses to the comment wrote: "What he derives is the Tully-Fisher relation but what he ignores is that the Tully-Fisher relation is empirical and it doesn't always give you an exponent of 4, in different bands (colours of light) you get a different answer.
The Tully-Fisher relation is not the issue (it can be explained by appealing to galaxy formation), the main issue is rotation curves which he hasn't shown he can explain. He claims all velocities should reduce to one universal number, but rotation curves don't all flatten out at one number. Then there is gravitational lensing and the CMB power spectrum.
He makes other mistakes too, his claims about dark matter are confused and his evidence in the CMB mistakes the l=2 dipole for the monopole and hence gets his equation wrong. His formula in the end is not only wrong but is flat out wrong at smaller scales."
The poster was not inclined to raise his criticism with you, so I am doing it. How would you respond?
Thanks for telling me. The commenter says the T-F relation is not the issue & it can be derived by appealing to galaxy formation. What they mean is: with many assumptions & fudging parameters. In contrast MiHsC can predict T-F with no fudging. There are still details to be worked out, I tend to simplify in my work, and not all galaxies are discs, as I assumed, but MiHsC predicts within uncertainty over a huge range of scales. This should not be ignored.
My equation is not as he says 'flat out wrong at small scales', because the new MiHsC term is 1/2L, so for big L (smaller scales) it reverts to L-CDM which is OK at small scales. My paper on this is: http://www.mdpi.com/2075-4434/2/1/81
It is true that not all galaxy rotation curves level out, but most do. The way I applied MiHsC to the systems in the paper was a necessary simplification. What is needed, despite my mistrust of them, is a computer model of a galaxy/cluster which includes specific code to change the inertial mass of a star depending on the mutual acceleration of nearby matter. I've written simple computer models to do this, but to convince the mainstream it'll have to be a well-known model with MiHsC inertia added.
http://ve2zaz.net/Presentations/Downloads/VE2ZAZ_24GHz_Gunnplexer_Presentation.pdf This is re. the 24 GHz idea I'm working on :-)
OK, so here's the response pasted below with a link to the conversation. I encourage you to respond directly if you'd like.
>with many assumptions & fudging
>parameters. In contrast MiHsC can
>predict T-F with no fudging.
But it's an idealised equation. An exact prediction of an inexact relation isn't a good result in my mind.
>because the new MiHsC term is 1/2L,
>so for big L (smaller scales) it
>reverts to L-CDM which is OK at
>small scales.
Which doesn't work. He has removed dark matter, the power spectrum with OmegaB=Omeg0 is totally and completely wrong. You can't dismantle LCDM and then appeal to it. I skimmed his paper it doesn't hold up.
>It is true that not all galaxy
>rotation curves level out, but most
>do.
He's misunderstood the point completely. My issue is not that rotation curves are flat but that he claims they flatten because of some universal minimum acceleration but if that were true why would galaxies have different outer velocities? That's what T-F relates. I'm not sure how some minimum acceleration like that gives you a flat velocity profile, so far as I can see it would be 1/sqrt(r).
http://www.reddit.com/r/Futurology/comments/34cq1b/the_facts_as_we_currently_know_them_about_the/cqvgpom
IMO your model is valid for normal photon drive (which predicts the drag in range of few micronewtons/1 kW) http://blog.xkcd.com/2008/02/15/the-laser-elevator - not EM drive.
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