The Casimir effect, MiHsC, & Emdrive

I’ve published a paper showing mathematically how MiHsC predicts the emdrive (see the reference below), but the struggle is to convince people with an explanation that takes them from what’s known & solid and guides them into this new area. This is one of the, possibly flawed, ways I use to explain it to myself. Starting from the known: the Casimir effect is well tested (see below left). If you put two conducting plates (the black lines) close together, these damp the zero point field (orange wiggles) between them, more virtual particles hit the plates from outside then from inside & the plates move together (red arrows).

It has also been noted, this time in fluid dynamics that if you subject a boomerang-shape to random perturbations (the middle diagram above) then it also has a shadow-zone for waves between its arms, and in this case the waves push it rightwards, since the waves put inwards (and rightwards) on the arms, but there are no waves to push from inside out (and leftwards) (eg: Chakrabarty et al., 2013). Now, imagine the reverse, where you have the same boomerang shape, but the random field is more intense inside (see the right hand diagram above). This is like the emdrive whose internal em field is high. By symmetry, the boomerang now moves towards its narrow end. We’re getting close.

The MiHsC explanation of emdrive is in a similar line but the derivation is more difficult because there’s no open end now. MiHsC says that the zero point field can be made to vary in space by setting up horizons (these can be real Casimir plates or abstract information horizons). In the emdrive then the supercharged zero point field in the copper cone is more energetic at the wide end (see diagram below, note the waveforms shown are cartoons only). There is now a gradient in it from which work can be extracted, just as the Casimir effect gets energy to move from the gradient it creates in the zero point field.

One way to work out the effect of MiHsC on the emdrive is to consider the photons resonating within it. On moving towards the wide end of the cone, the photons are moving to a more energetic zero point field and so gain inertial mass due to MiHsC (yes, light has inertial mass, the Japanese have just tested a light sail: IKAROS). Going the other way the photons lose mass. The almighty cosmic accountant says "Oh dear! Net mass is going towards the right, so I'd better conserve momentum & move the emdrive to the left. Make it so!". In this new way MiHsC predicts the observed emdrive thrust quite well. As shown in the bar chart below which shows the thrust data (the purple bars) from the eight emdrive experiments so far, and the MiHsC prediction in red. For the details, see my paper below.

References

Chakrabarty, A. Konya, A., Wang, F., Selinger, J.V., Sun K., Wie, .H., 2013. Brownian motion of boomerang colloidal particles. Phys. Rev. Lett., 111, 160603.

McCulloch, M.E., 2015. Testing quantised inertia on the emdrive. EPL, 111, 60005. PDF

Comment on LIGO Gravitational Waves

The LIGO project is a bit like a rich man's Michelson-Morley experiment. To simplify the explanation, they fire a laser beam into the centre of the contraption, which splits the beam sending it down two perpendicular 4km arms to mirrors. The beams bounce back to the centre and are redirected to a detector which checks to see if the peaks and troughs of the light waves are still aligned. Last week LIGO announced that the emerging waves were very very slightly not aligned, implying that the difference in the two arms' lengths had varied by 0.0001 times the width of a proton in a way that looked like the gravitational waves predicted by general relativity (GR) due to two black holes merging.

I've been asked whether this is relevant to MiHsC. The answer is that if it really is from a high acceleration distant process then 'no' since MiHsC usually only makes a difference to GR at very low accelerations or large scales (of the order of 10^-10 m/s^2, or tens of kpc), and at higher accelerations MiHsC reduces to general relativity since in that regime the MiHsC inertial mass tends towards the gravitational mass (if it's due to local changes in light speed, then it might be relevant).

The search for new data is a fantastic thing, so LIGO should be congratulated for that. The thing that bothers me about the gravitational wave paper is whether the twin black-hole merger scenario they pigeon-holed it with can be falsified or tested independently? I suspect it can't, and so this is like a lot of post-modern physics: unfalsifiable.

Imagine someone invents a Theory of Exploding Mushrooms (TEM). They have brilliant success predicting small mushroom blasts at home. Then people using ear-horns hear odd bangs from the distant forest. "It's my theory of exploding mushrooms!", the scientist says in glee and enthusiastically calculates the size of the unseen mushrooms that may be exploding. No one can go to check this prediction, and some people grumble that with the greatest respect, the TEM actually only managed to predict 4% of the exploding mushrooms that have subsequently been seen on the edge of the forest, and also the theory is incompatible with the famous Theory of Quantum Fungi...

In the gravity wave paper (see below) they say that the merger and the 'ring down' of the black hole are consistent with each other given GR, but this is an example of fitting using a computer model. They have found the black hole model that fits the data, but no one can go and look. It is not falsifiable. So it is not science.

Carl Sagan once said: extraordinary claims need extraordinary evidence. This applies to this case. They are invoking extraordinary directly-invisible entities and this needs independent backup. I feel that the usual standards are not being applied to the pathway that the majority of physicists occupy.

References

Abbott, B.P. et al., 2016. Observation of gravitational waves from a binary black hole merger. PRL, 116, 061102. http://arxiv.org/ftp/arxiv/papers/1602/1602.03837.pdf

Presentation on MiHsC

I haven't posted here for a few weeks because I've been inundated preparing a new Space Exploration course for Plymouth University First Year Students. Today, after going through relativity and the philosophy of it, I finally gave the students (a good keen bunch) a presentation about my own work.

I started by pointing out the big problem, which has been brushed under the carpet, which is that galaxies spin too fast in their outer parts and the centrifugal forces should pull them apart. I mentioned the deeply unpleasant hypothesis of dark matter that is added to their edges to make general relativity fit the visible mass and velocity data. I added the interesting commonality which is that the problems always start at galactic radii when the stars go below an acceleration of around 10^-10 m/s^2 and the observation that globular clusters (star congregations within galaxies) show the same odd behaviour as large galaxies but dark matter can't be used to fix globulars because it has to stay spread out at the galactic edge to fix the galaxies.

I then showed how an object accelerating in one direction develops a Rindler horizon in the opposite direction and this damps the Unruh radiation in such a way that more radiation hits them from in front then from the back and how this predicts inertial mass for the first time (McCulloch, 2013). In the past it's always been assumed that "things keep going": shallow language only.

I then showed that this new model (MiHsC) predicts that inertia dissipates in a new way at very low accelerations in just the way needed to explain galaxy rotation without dark matter (McCulloch, 2012). The predicted effects also appear at that critical acceleration of 10^-10 m/s^2. MiHsC also predicts the recently observed cosmic acceleration without dark energy (McCulloch, 2007, 2010) and fits the low-l CMB anomaly and the pioneer and Tajmar anomalies, the emdrive & others. I then briefly went through Maxwell's Demon, Szilard's Engine and Landauer's principle and showed how I'm now attempting to re-derive MiHsC using information loss on horizons and how I can get similar formula, but with an as-yet too simple model.

Just when the students were recovering from this I showed them a swastika (no politics here) and told them that if this was put nanoscale into the zero point field then it would act like an array of Rindler horizons, and create new circular motion to generate energy. I showed them Luke's speeder on Tatooine and said all it needs is an Unruh-damping horizon above it to float, and a fuel-less interstellar vessel, with a horizon in front which should move getting its energy from the inhomogeneity in the zero point field caused by the horizon.

Some of the students said they were 'Blown away'. So it'll be a hard lecture to follow: my next lecture is on exploration by maths (what I do most of the time), then 'alien possibilities'. Anything short of presenting a stargate is going to be a dissapointment, but dissapointment too is an education: these things are not flash in the pan. It's a long hike, or should I say trek? It's now over 10 years since I started.

References

McCulloch, M.E., 2013. Inertia from an asymmetric Casimir effect. EPL, 101, 59001. http://arxiv.org/abs/1302.2775

McCulloch, M.E., 2012. Testing quantised inertia on galactic scales. A&SS. Vol. 342, No. 2, 575-578. http://arxiv.org/abs/1207.7007

McCulloch, M.E., 2010. Minimum accelerations from quantised inertia. EPL, 90, 29001. http://arxiv.org/abs/1004.3303

McCulloch, M.E., 2007. Modelling the Pioneer anomaly as modified inertia. MNRAS, 376(1), 338-34. http://arxiv.org/abs/astro-ph/0612599

Ulysses also showed a Pioneer anomaly

In 2011 it all went quiet on the Pioneer anomaly, because some studies found they could model it assuming complex thermal emission, and so the community was quickly brought into line and ever since at conferences I've been told off whenever I mention it, which makes me feel even more that it is my duty to mention it.

First of all, and this is something you never hear about, the Pioneer anomaly was also shown by another spacecraft: the Ulysses spacecraft which was launched, via a gravity assist at Jupiter, into an orbit around the Sun out of the plane of the ecliptic. The Ulysses orbit could only be explained, said Anderson et al. (1998) (see ref below, page 2) if they included an unexpected acceleration of 12+/-3x10^-10 m/s^2 towards the Sun, in agreement with the Pioneer anomaly of 8.74+/-1.33x10^-10 m/s^2. The Ulysses spacecraft had a different orientation to the Pioneer craft so it's very unlikely thermal emission would apply in the same way.

This supports my opinion that the Pioneer anomaly has been brushed under the carpet by a complex thermal model (that has 1000s of finite elements and two adjustable parameters) rather like the galaxy rotation anomaly has been brushed under the carpet using vague and complex dark matter models. Uncomfortable contrary data like the Ulysses data in the case of Pioneer, or dwarf galaxies in the case of dark matter, have been hidden away in a dark closet like a grumbling relative with a higher standard of cleanliness, but they are still there, muffled but more determined than ever to expose sloppy practices.

Going further, the Pioneer anomaly is not only supported as an anomaly, to the standard model, by the Ulysses data, but also by the galaxy rotation anomaly, the anomalous cosmic acceleration, the flyby anomalies, dwarf galaxies, the Tajmar effect, the emdrive and many more, all of which are easily solved by the same acceleration shown by the Pioneer craft, an acceleration that appears naturally within the framework of MiHsC (see my papers below for the solutions for the Pioneer, galactic and cosmic acceleration).

The fact that the same number 2(SpeedofLight)^2/(HubbleScale) ~ 8x10^-10 m/s^2 keeps cropping up all over the place, should really get massive attention. This is direct evidence for MiHsC, because only MiHsC predicts that crucial number (even in MoND for example this odd number has to be put in by hand).

 References

Anderson et al., 1998. Indication from Pioneer 10/11, Galileo and Ulysses data of an Apparent Anomalous, Weak, Long-range Acceleration. Phys.Rev.Lett. 81 (1998) 2858-2861. http://arxiv.org/abs/gr-qc/9808081
McCulloch, M.E., 2007. Modelling the Pioneer anomaly as modified inertia. MNRAS, 376, 338-342. http://arxiv.org/abs/astro-ph/0612599   
McCulloch, M.E., 2010. Minimum accelerations from quantised inertia. EPL,, 90, 29001.
McCulloch, M.E., 2012. Testing quantised inertia on galactic scales. A&SS, 342, 2, 575-578. http://arxiv.org/abs/1207.7007

Interstellar MiHsCjet

Yesterday, I gave a talk titled "Human Space Exploration: from Tsiolkovski to Time Peake" to the Plymouth Astronomical Society, and talked at the end about interstellar travel. I explained how relativity means you can get to any star in the galaxy in the lifetime of those travelling (but not those left on Earth) if you can accelerate quickly (to avoid the effects of general relativity on time), get close to the speed of light (c) and cruise, then special relativistic time dilation slows everything down on the ship. It works a bit like suspended animation but without the need for cryogenics. For example, if you accelerate for an Earth-year at 9.8 m/s^2, then cruise for 23 Earth-years at 0.9c, then decelerate equally quickly, you can get to Gliese 667 (which is Earth-like and 23.6 light years away) in about 25 years as measured from Earth and only 12 years as experienced on the ship. I then made the crucial point that travel agencies are not yet offering package tours to Gliese because accelerating to 0.9 times the speed of light takes over 300 times the energy generated by our civilisation in a year.

Not to worry: there are a few bold suggestions for how to get to 0.9c, including antimatter rockets that are propelled by radiation from, for example, electron-positron annihilations, interstellar ramjets that focus and fuse hydrogen collected in deep space, so they avoid carrying heavy fuel and so can accelerate more easily, and Alcubierre drives that bend space and unfortunately need negative matter. I also mentioned my own suggestion (McCulloch, 2013) which is a MiHsC-drive which, like the ramjet, avoids carrying fuel. It is shown in this schematic:

The circle in the centre is the spacecraft core, and it holds in front of it a metamaterial shield (the dashed curve on the left) that can damp Unruh waves. If the spacecraft is accelerated it will see Unruh radiation as shown by the red & orange wavy lines all around it. If the metamaterial shield is set up the right way it will disallow waves in front of the spacecraft (left) so there will be fewer there (the orange wave has less amplitude) and the craft will feel more Unruh radiation pressure from the back then from the front and this will accelerate it forward (the black arrow), and it will do it without the need to carry fuel. The fuel, like the ramjet, is available en route: in this case from the quantum vacuum, made inhomogenous by a manmade horizon. Note: I think the emdrive is inhomogenising the vacuum in a similar way (see McCulloch, 2015).

References

McCulloch, M.E., 2013. Inertia from an asymmetric Casimir effect. EPL, 101, 59001. http://arxiv.org/abs/1302.2775

McCulloch, M.E., 2015. Testing quantised inertia on the emdrive. EPL, 111, 60005.  http://iopscience.iop.org/article/10.1209/0295-5075/111/60005

Testing MiHsC in Dwarf Galaxies

The best test of MiHsC is to find circumstances where it is likely to appear - that is, in systems in the deep of space with very low accelerations. I've recently been looking into some ideal candidates: Milky Way dwarf spheroidal galaxies. The Milky Way has lots of these tiny systems orbiting around it and some of them are so wispy that they should show up MiHsC, and they do. The plot below shows the five wispiest cases I could find that also have observations of their stars' orbital velocity. In the figure the x-axis shows the visible mass of the system (in Solar masses) and the y-axis (black squares) shows the velocity (km/s), for the dwarfs Segue-1, Triangulum-II, Bootes, Coma Berenices and Ursa Major 2. The error bars (uncertainties) are also shown.

The first thing that can be done is to calculate the maximum orbital speed that Newton would allow without the systems becoming gravitational unbound given their visible mass (general relativity predicts similarly). These maximum Newtonian velocities are shown with crosses and are much smaller than the stars' observed speed which implies that the dwarfs should explode centrifugally (inertially) because of the inability of their visible mass to bind them gravitationally. However, they look bound. Dark matter enthusiasts will no doubt say "Just add dark matter", but in the case of Segue and Triangulum-II you have to add 2600 and 3600 times as much dark matter as the visible matter, which makes the dark matter hypothesis look ridiculous.

Another possibility is to use MoND, Milgrom's empirical formula that modifies gravity or inertia, and the results of that are shown in the Figure by the triangles. MoND uses an adjustable parameter a0 of 1.8x10^-10 m/s^2 and also predicts too low a maximum velocity: outside the uncertainties in the observed velocities in all but one case: Coma Berenices, but it is much better than Newton, or 'naked' GR.

Finally, the predicted maximum velocity of MiHsC is shown by the diamonds (using the same method I used for full scale galaxies in the reference below). MiHsC is the closest to the observations and agrees, given the error bars, with all but one of the observations (Triangulum 2). It certainly performs the best, which is impressive given that, unlike dark matter and MoND it has no adjustability. My goal now is to emulate Gandalf and collect a few more dwarfs, the lighter the better.

References

McCulloch, M.E., 2012. Testing quantised inertia on galactic scales. A&SS, 342, 2, 575-578.  Preprint

Comparison of GR, MoND, MiHsC

One of the great advantages MiHsC has, and that doesn't seem to be appreciated, is that it fits a lot of data without needing adjustment, so here is a table to emphasize that. In the left hand column I've listed eleven anomalies and in the other columns I've used a colour code to show how the theories listed at the top (General Relativity, MoND and MiHsC) fit the data. If the theory can't fit the data because it would need ridiculous amounts of adjustment then I've coloured the square red. If the theory can fit with an adjustment that needs more than one arbitrary number to define it (eg: the addition of dark matter) I have coloured the square orange. If the theory needs adjustment with only one arbitrary number the box is green, and if it needs no adjustment at all the box is blue.

It is inevitably a vague comparison, but general relativity produces a lot of orange (it fits, but with a lot of adjustment) because of its flexibility, aided by huge numbers of scientists with computers, arbitrarily adding dark matter and energy. MoND, which is simpler and has only one adjustable parameter shows more green, but also some red, because it has less flexibility and, for example, it cannot cope with galaxy clusters, nor the new data coming from labs, like the Tajmar effect and Shawyer's emdrive. 

MiHsC performs well without needing adjustment at all (lots of blue). This is because I have designed it from the ground up with some of these anomalies in mind from the start. This is how science should be done: working from the data to a theory, not, as is done with general relativity, by fudging a revered theory to fit the data. The details of this table are open to debate, but MiHsC obviously performs best on this measure, and more generally: scientists should try to propose theories that produce a conclusive red or blue, not orange.