I chose the title Physics from the Edge because the theory of inertia I have suggested (MiHsC) assumes that local inertia is affected by the far-off Hubble-edge. My webpage is here, I've written a book called Physics from the Edge and I'm on twitter here: @memcculloch

Saturday, 16 January 2016

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

Saturday, 9 January 2016

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

Saturday, 12 December 2015

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

Sunday, 6 December 2015

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.

Sunday, 29 November 2015

Dark Matter Jumps the Shark

Mainstream theoretical physics needs to take a long hard look at itself. I've just read an article about Lisa Randall's new suggestion that dark matter killed the dinosaurs and after collapsing in a tangled heap of laughter I realised that this perfectly captures the attitude of mainstream theoretical physics: the extrapolation of untested and possibly untestable hypotheses into a regime where you are unlikely ever to be proven wrong, like the interior of black holes, the first millisecond after the big bang or the age of the dinosaurs. It is the physics of the unimaginative and cowardly.

Dark matter is like a universal plaster for any anomaly. For galaxies stick the invisible stuff freely onto your equations in a halo. For the flyby anomalies put it in a thin disc, for the dinosaurs it is a layer (I refuse to look at the details, like I refuse to read up on ghostology). There's a useful idea called Russell's teapot (pointed out to me by DaKangaroo on twitter). Bertrand Russell said that if someone claims there's a teapot orbiting the sun between Mars and Jupiter the onus is on them to prove it, certainly before expecting people to believe anything else deduced from it (By the way, I'm not saying dark matter can't exist at all in some minor form, just not as it is taken by the mainstream as a panacea for all their problems).

In contrast to dark matter's arbitrary flexibility, MiHsC is unadjustable. This means that, unlike the dark side, I can't cheat. MiHsC only predicts one possibility, and yet that possibility correctly models the observed anomalies I've tried it on: galaxy rotation, cosmic acceleration, the orbit of Proxima Centauri, the spin of extreme dwarf galaxy Triangulum II, the Pioneer and flyby anomaly, the Tajmar experiments and the emdrive. Meanwhile the mainstream is messing around with the insides of black holes, the early universe and the dinosaurs, confident no-one can disprove them.

But there is hope. In the fifth season of the TV series Happy Days ratings were falling so that the writers wrote in a scene where Fonzie jumped over a shark on skis. Ever since then a useful phrase has entered the English language: to 'Jump the Shark' meaning to use shock tactics to retain dying interest. There's now a similar term 'Nuke the Fridge' based on Indiana Jones 4. The dark matter bandwagon has just jumped the shark, so things may now get interesting.

Sunday, 22 November 2015

Evidence for MiHsC: Triangulum II

The usual balance in systems such as galaxies is between gravity which holds them in (keeps them bound) and the inertial centrifugal force that tries to explode them. In all the systems we see today these two forces must be balanced, or we wouldn't still see them. Writing this balance mathematically gives

G*M*mg/r^2 = mi*v^2/r

where G is the gravitational constant, M is the galaxy's mass within a radius r, mg is the gravitational mass of a star at radius r, v is its orbital speed and mi is the star's inertial mass (usually it is assumed that mg=mi, the equivalence principle). For the amazingly low accelerations in deep space MiHsC proposes that mi is much less than mg so that a gravitationally bound system should appear to have stars orbiting too fast, this is indeed the case. This is because MiHsC reduces the centrifugal force breaking them apart, allowing them to spin faster without exploding. Therefore, to prove MiHsC, a good plan would be to look for galaxies with mindbogglingly low accelerations, ie: low mass ones.

The most extreme such system has just been found by Laevens et al. (2015). Triangulum II is a dwarf galaxy, one of many orbiting our Milky Way galaxy, with very little visible mass in it: only 450 times the light output of the Sun, so the equivalent of 877 Suns in mass (Assuming star type K0 - thanks to Javier Freire Venegas for putting me right on the mass/light ratios) and it is only 34 parsecs in radius.

As expected, both Newton's and Einstein's models (General Relativity, GR) have a problem with this dwarf galaxy because they predict that any rotation speed above 0.34 km/s would blow it up (v=(GM/r)^0.5). But, Kirby et al. (2015) have just seen the stars zooming around it at 5.1 km/s! (with an error bar meaning that the speed is somewhere between 3.7 and 9.1 km/s). Assuming that this system is stably bound (something probable, but still debated) then to keep Newton and Einstein happy and stop it exploding you'd need to add 3600 times more invisible dark matter to it than the visible matter present. This is clearly becoming ridiculous.

MoND does a slightly better job. The MoND formula, which is v=(G*M*a0)^0.25 predicts an orbital speed of 2.1 km/s, but MoND relies on an adjustable parameter a0 which must be set by hand to be typically 1.8x10^-10 m/s^2 and MoND has nothing to say about where this number comes from.

MiHsC does an even better job, and it contains no convenient adjustable parameters. The MiHsC formula, v=(2GMc^2/Theta)^0.25, predicts a rotation speed of 3.0 km/s (in this formula c is the speed of light and Theta is the Hubble diameter). This Table summarises the observed speed and the various predictions:

  Observed     = 3.7-9.1 km/s (range of possible velocity dispersions)
  Newton/GR  = 0.34 km/s
  MoND          = 2.1 km/s
  MiHsC         = 3.0 km/s

Whether or not MiHsC agrees with the observation depends on the error bars in its prediction, and so I need to know what the uncertainty of the mass given for Triangulum II is (I'm writing a paper so will have to look closely at all the error bars), but the MiHsC prediction is clearly the best in the Table. As for the dark matter hypothesis, the amounts needed for this particular case are clearly ridiculous.

References

Kirby et al., 2015. Triangulum II: possibly a very dense ultra-faint dwarf galaxy. Astrophysical Journal Letters, 814: L7. Pdf

Laevens, B.P.M. et al., 2015. Astrophysical Journal Letters, 802: L18.

McCulloch, M.E., 2012. Testing quantised inertia on galactic scales. Astrophysics & Space Science, 342: 575-578. Preprint

Saturday, 14 November 2015

A Case for Human Spaceflight

I spoke at a debate at Exeter University's debating society yesterday in favour of human, as opposed to robot, space exploration. Here is roughly what I said:

I would say that human spaceflight and settlement off-world is as inevitable and natural as the first fish crawling out of the sea, or humans leaving Africa, and this is why:

It is already possible, given the will: Six humans are living in space on the ISS which is already providing a dividend in showing Americans and Russians that they can co-operate. For this reason the ISS has been suggested for a Nobel prize. The Moon and Mars are settle-able in the next few decades, the Moon being the obvious first choice.

Even interstellar travel is more possible than you might think because special relativity says that time slows down aboard a spaceship moving very fast. So if you have an engine powerful enough to get you close to the speed of light, you can travel anywhere in the galaxy in the lifetime of a human on the ship, just not in the lifetime of people back on Earth. This gets rid of the need for generation-ships or suspended animation and reduces galactic colonisation from something that most people think is an impossibility, to merely a extremely difficult engineering problem (you have to accelerate and decelerate at 1g, 9.8 m/s^2, for a year, and then cruise).

New physics is coming, since general relativity has difficulty with galaxies (needing arbitrary dark matter), with cosmology (needing dark energy) and is inconsistent with quantum mechanics, and there are experimental problem like the EPR-Bell tests and other anomalies. I have suggested MiHsC to fix these problems.

Where do we go? Well, this is the time and place to ask that. Many exoplanets are now being discovered, some will be like the Earth, and one of the main centres for exoplanet research is here at Exeter University.

So if it is possible, is it a good idea? I would argue yes as follows:

Insurance: Humans have had a long and painful struggle to civilise (well, partially anyway) and we have something unique to say. It would be a shame if that was lost. Off-world colonies are essential so that if the Earth is damaged by an asteroid, nuclear war or climate change, humanity will endure and our long history will not be in vain.

Finite planet: Earth's resources are finite, and yes, we should learn to be sustainable, this will also help us with space travel and settlement, but even with sustainable policies, resources will eventually run out on the finite Earth. Space offers infinite or at least mind-boggling resources.

The need for challenge: humans have an innate need for challenge, and the challenges on Earth are running out and in these circumstances there is the danger of degenerating into a stagnant heirarchical society where a few try to make money off the rest. We need a collective and hopeful project, like Project Apollo, to bind our society together and give everyone hope of a better future. Hope is important. Also, the failures of a system can often only be seen by looking at it from the outside, that is increasingly difficult in our connected world.

Cultural diversity: The culture of Earth is becoming more uniform and this is a shame since it leads to sterility. There is very little option now to try radical new ideas on Earth, but if some people left the planet they could start radically different societies and experiment with them, just as the Pilgrim fathers did and devised a better constitution, and other brilliant inventions, eg: pizza.

The imperative: If we look at plants & animals we see the huge resources they put into reproduction, for example Salmon return over whole oceans to their birth place to reproduce. Evolution has made them that way since the ones who couldn't be bothered left no offspring. Lovelock has suggested that the Earth is an organism. If so, then it is logical to say it intends to reproduce. Is it developing us, a space-faring species, to do that?

Exploration by proxy is shallow: History tells us that if you send people to new environments, in this case other planets, they'll invent things we'd never dream of. One example is Charles Darwin who went to the Galapagos Islands and noticed the animals varied from island to island and thought of evolution. Robots are not yet creative like this. A robot on the Moon may be the eyes for someone back on Earth, but that someone is still on the Earth sat on a chair. If the person was on the Moon, they would think in a different way and could be a new Thomas Jefferson or Darwin, inventing a better society or a better way to generate energy.

The importance of human exploration is instinctively understood: almost no-one remembers the first probe to the Moon (Luna 2) but everyone remembers the first human. You can’t predict the ideas space settlers will have, but you can help it to happen by voting for human spaceflight today.