

Tuesday, 2 June 2015

What you can see is what you get













qraal said...

Point of historical fact, but epicycles were "seen" since they represented a fitting of the model (circular geocentric motion) to the observations of the "reversals" of the exterior planets. Likewise "dark matter" and "dark energy" - they're all observed by their presumed effects vs what plain Keplerian or Newtonian models predict. And dark masses aren't such a weird thing, considering that only stars can be seen by their own light. The real problem is when the current models get elevated into untouchable "truth" and observations get shoe-horned into fitting the model - I suspect the non-observation of super-symmetry and the dogmatic insistence on the "truth" of string theory might be a good example.

Yet the early days of Copernicanism might be a counter-example. Many geocentric astronomers who used telescopes to observe the stars in the 17th Century were sceptical of Copernicanism because the implied sizes of the stars were ridiculously large. In the early telescopes stars could be seen as disks. The Tychonian and Ptolemaic model of the cosmos only had the stars at ~twice the distance of the outermost planet, Saturn, thus seeing the stellar disks was reasonable.

Copernicanism's chief prediction of annual stellar parallax suffered from the fact no one could observed it. The non-observation of parallax implied the stars had to be at least 1,000 or 10,000 times further away than the Tychonian/Ptolemaic model. Thus the observation of stellar "disks" seemed to be evidence against Copernicanism.

Of course once diffraction patterns were understood and the stars were demonstrated to be unresolved "points", then the problem went away. Observation of parallax wasn't achieved until the 19th Century, 300 years after Copernicus.

Mike McCulloch said...

Thank you for your sensible and interesting comments, but let me make my point clearer:

What I mean by 'seen' is that entities used in models need to be directly measurable in a pre-specified way, at least in principle, and also in a different context to what first suggested them. The Unruh radiation I use in MiHsC may or may not have been detected already, but it is at least clear specifically what to look for. This is unlike epicycles whose mechanism was unknown & therefore undetectable and dark matter which is a vague wait for something, anything, to turn up.

As for Copernicanism, it wasn't the parallax that convinced people 300 years later, by then Copernicanism was long accepted, but the much earlier observation of the full set of phases of Venus by Galileo, eg slide 4 of: http://www.astro.umd.edu/~miller/ASTR100/class6.pdf

Interesting point about the stellar disks..

qraal said...

Nice point about the wait for "dark matter" to turn up, though it's a bit misleading to say people have no idea what it is (i.e. that it's a "vague wait".) The real problem is there are too many candidates which means a lot of parameter space has to be explored to eliminate the suspects, following Sherlock Holmes' dictum to eliminate the impossible. There's also a lot of theoretical suspects in the line-up. A good alternative theory should explain a lot of other phenomena too, rather than being an ad hoc "fix" - your theory is more the former, while some proposed "plug-ins" for GR are the latter. Not sure where MOND fits.

Tommi Kiviniemi said...

I am a huge fan of yours. There's so much I find nonsensical in the "new" physics that it's refreshing to see someone taking a more traditional and, dare I say it, scientific approach to this. Occam's razor is right most of the time, and I am glad that you are wielding that blade heavily.

qraal said...

Hi again Michael,
One thing which intrigues me about your inertia theory is how it accounts for all but 29% of inertial mass. I wonder where the rest of it might be found?

Tim Goff said...

Mike, have you been keeping track of 'WarpTech' (Todd) over at NSF? He seems to be trying to tunnel into your theory by way of the basement at times.

Mike McCulloch said...

Tommi: thanks for your support. Occam's razor is indeed very valuable. In my opinion it has been overwhelmed by the invention of computers, which are hugely useful, but do make very complex fixes like dark matter easier to implement. The old razor needs to be sharpened to cope with this.

Mike McCulloch said...

Qraal: Good question. One assumption I made in the derivation is that the Rindler horizon is c^2/acceleration away. This is a simplification, so I'm looking into that. There were a few other simplifications as well..

Mike McCulloch said...

Tim: I've noticed WarpTech's PV-based scheme, but I don't see how it could be right because (although I can't find the details or a derivation) it seems to predict that the emdrive's thrust depends only on the geometry of the cavity and not P (power input) or Q (quality factor) but all the data so far suggests that thrust is strongly proportional to P and Q (in this work you have to mind your Ps and Qs). Also, like many others, he doesn't compare with the data which should be the first step.

Tim Goff said...

Mike - have you noticed as of late at NSF there is a fair bit of head scratching going on about Q, especially with regard to the Chinese results? (Yeng and Fan). Lowest Q, worst design factor, shallowest cone angle...and unless something is screwy with the data...best thrust of any of the EM Drive designs. WarpTech seems to be the only one with a theory that could account for this, but as you pointed out, there are multiple issues with his approach.

You have any ideas on how the Chinese results fit into the rest of the EM frustration?

Mike McCulloch said...

The Chinese (Yang et al.) results are an anomaly within an anomaly. I could predict them quite well with MiHsC when I used their own quoted Q factors: 32000 and 50000, but the indefatigable NSF folk have shown that their Q factor, when calculated consistently with those in the west, is much lower (1531) so, as you say, their thrust is 1000 times larger than expected. If their thrust values were in microN not milliN they'd make sense, but I'm sure they've been careful that way! I think there should be more interaction between the teams to iron out differences: a workshop should be organised to get everyone together, like the useful workshops I went to on the flyby anomaly at ISSI in Bern, Switz., and on big G at the Royal Society.

Tim Goff said...

One of the DIY types at NSF (SeaShell) is attempting to duplicate the Yang/Fan device. Perhaps that will help.

Current consensus at NSF is the second Hackaday test (Baby EM Drive) was a null result. They really, really want the data for an unpowered (drive off) version of test 1.

I wonder if a graph of the various devices cone angles and lengths verses...'something else'... would reveal anything? Rodal did come up with dimensions for the Chinese device, and seems to think there is something critical locked in that data

qraal said...

Hi again Mike

This might be interesting... http://arxiv.org/abs/1506.04099

A universal velocity dispersion profile for pressure supported systems: evidence for MONDian gravity across 12 orders of magnitude in mass

For any MONDian extended theory of gravity where the rotation curves of spiral galaxies are explained through a change in physics rather than the hypothesis of dark matter, a generic dynamical behaviour is expected for pressure supported systems: an outer flattening of the velocity dispersion profile occurring at a characteristic radius, where both the amplitude of this flat velocity dispersion and the radius at which it appears are predicted to show distinct scalings with the total mass of the system. By carefully analysing dynamics of globular clusters, elliptical galaxies and galaxy clusters, we are able to significantly extend the astronomical scales over which MONDian gravity has been tested, from those of spiral galaxies, to the much larger range covered by pressure supported systems. We show that a universal projected velocity dispersion profile accurately describes various classes of pressure supported systems, and further, that the expectations of extended gravity are met, across twelve orders of magnitude in mass. This observed scalings are not expected under dark matter cosmology, and would require particular explanations tuned at the scales of each distinct astrophysical system.

Michelle Nosearchomme said...

Hi Mike,

This is SeeShells from NSF blog. At first I wasn't sure I liked your ideas of Unrah radiation. I think it was just the name that threw me off to dig deeper, but dig I have and the more I comprehended the more I believe there is a lot of merit in your ideas. Plus, I dislike the idea and theories of Dark Energy and Dark Mass just a little more. Reminds you of the technobabble in Star Wars doesn't it? When they tried to explain the rotational rates of galaxies with it I thought this doesn't make any sense at all.

I am retired, well somewhat retired. I still get to poke my head out of my lassitude to consult in my old field running my company building semiconductor equipment or chase building massless thrusters like the EMDrive. I currently have 2 standard designs I'm building using what could be considered the thrusters. The first is based on Shawyer's size and dimensions not because I believe his theories have a lot of merit but because he has reported thrust and the second one is one made in an hexagonal shape with holes in the outer Frustum's metal, the large end is an expanded copper and a open (tuned) grid in the small end and this one I'll do to the Chinese dimensions.

I want to do a third one. Even though I have a couple ideas (longer ~4x) I would love to hear what you would think the design parameters should be. PM me if you would like.


Mike McCulloch said...

Hi qraal. I'm glad to see X. Hernandez is testing MoND against the data, but I'd like to point out that MoND needs an adjustable parameter a0 to be set by hand, and has no specific physical model. MiHsC has a physical (inertial) model and doesn't need a tuning parameter. I published a similar MiHsC-data comparison over a similar range of masses in 2012. The preprint is here:


I also discussed it in this blog entry:


Mike McCulloch said...

Hi Michelle. Thank you for your positive comments about MiHsC, and I commend you, and the others, for your positive attitude in building an emdrive. We desperately need more data to test the various theories and it's great to see so many rising to the challenge, while mainstream physics is focusing on the unfalsifiable dark matter and dark energy and dismissing so many interesting anomalies. I have a particular cavity geometry in mind for an experiment. Let me get back to you soon on that..

qraal said...

Hi Mike

Any evidence for MOND is evidence for MiHsC if I've read your arguments correctly. Or rather any evidence distinguishing MOND from CDM. MOND is merely the empirical "line fitting" relationship that underlying MiHsC physics should produce, like the Tully-Fisher relation isn't a physical theory, but an empirical observation.

Mike McCulloch said...

Yes. The fitting parameter a0, which is put into MoND 'by hand', is predicted by MiHsC without the need for manual input (although the predicted a0 differs from that typically used by MoNDians, both predictions are within the uncertainty in the data).


My parents pulled me out of school, and did so since the school system basically said that smarts and me were not related at all. Thus I did not have a chance to receive any education in physics.

But back in grade 9 however, I made a point in science class about a difference that I had noticed concerning what you see, and what is real, when it comes to "motion". I was basically told to sit down and shut up. It was instantly assumed that I was speaking of nothing but pure rubbish. However, years later in my spare time at home from work, I reviewed my thinking and continued onward analyzing "motion".

I eventually understood motion, and did so in a unique manner. Via the use of simple geometry, I converted my understanding of motion into equations. I then borrowed a physics book to see if my equations were of recognition elsewhere. They turned out to be identical to the Special Relativity equations, along with the Lorentz transformation equations. My method of deriving these equations is found nowhere else on the planet. Because of that it constantly ignored due to today's global obsession with conformity, not uniqueness. Anyhow, have a look if you have the time.