A New Angle on Galactic Jets & FTL

Will Faster Than Light (FTL) travel ever be possible? Ultimately good observations, and not theory, will decide this, but, as I discussed in a previous blog, MiHsC suggests that the usual speed of light limit of relativity is flawed because it implies a constant speed, and therefore Unruh waves larger than the Hubble scale which are not observable.

If this is true, then where in nature might MiHsC act to accelerate something past the speed of light? One way to accelerate something with MiHsC is to move it towards the spin axis of another body. The object then sees lower mutual accelerations, loses inertial mass, and momentum conservation speeds it up anomalously. This prediction fits the flyby anomalies fairly well (McCulloch, 2008, see references below). MiHsC also predicts that the flyby anomaly can be much greater for larger, slowly rotating objects. Could the anomaly be so large that MiHsC accelerates something past the speed of light in this way?

Galaxies are pretty big objects and phenomena called galactic axial jets (jets shooting out along their spin axes) have been known for years. Biretta et al. (1999) looked at a particularly interesting one in M87. They looked at recognisable ‘knots’ of light within the jet, and found that they were moving at 6 times the speed of light (6c). It is important to note that Rees (1966) showed that the apparent speed of a relativistic object moving at an angle close to the line of sight (ie: jetting towards us) can appear to be superluminal, but that this is an optical illusion. There is a simple formula to calculate the ‘real’ speed from the apparent one and the angle. According to Biretta et al (1999) the most likely angle of the M87 jet to our line of sight is 64.5 degrees, and they said that because of the observed shape of the knots “placing the jet within 20 degrees of the line of sight presents several challenges”. If we assume the best guess angle of 64.5 degrees then the implied (real) velocity is still 3.7c (the apparent one is 6c). To get the implied velocity down below the speed of light you would have to assume an angle of less than 20 degrees, which they say is unrealistic.

There are more cases like this and, in a more statistically significant study presented at the Superluminal Workshop at Jodrell Bank Observatory in 1983, and mentioned in Porcas (1983), Schilizzi showed that the galactic jets with faster than light speeds did not extend from their galaxies any less than the sublight jets did. This suggests, if they're the same length, that the FTL jets are not close to our line of sight, and that their superluminal speeds might be real. However, this raises huge theoretical problems with causality, and of course there is the possibility that something is amiss with the jet observations, but I do believe that observations, and not old textbooks, will show the way.

Introduction to MiHsC

References:

Biretta, J.A., W.B. Sparks, F. Macchetto, 1999. Hubble space telescope observations of superluminal motion in the M87 jet. Astrophysical Journal, 520, 621-626. Free pdf

McCulloch, M.E., 2008. Modelling the flyby anomalies using a modification of inertia. Mon. Not. Royal. Astro. Soc., Letters, 389 (1), L57-60. Free pdf

Porcas, Richard (1983). "Superluminal motions: Astronomers still puzzled". Nature 302 (5911): 753. doi:10.1038/302753a0

Rees, M., 1966. Appearance of relativistically expanding radio sources. Nature, 211, 5048.

The Light Speed Limit & the Soyuz Express

The further you look away from the Earth, or, it is assumed, away from anywhere, the faster other galaxies appear to recede. This is the well-known Hubble expansion and it is seen in the increasing redshift of distant stars: their light is Doppler-stretched until at the Hubble distance they exceed the speed of light relative to us and dissapear from view, like ambulances travelling away faster than the speed of sound would be silent to us. This is one of the reasons the night sky is dark, and seems initially to be a problem since faster than light travel is supposed to be verboten. This paradox is usually avoided by saying that space itself is expanding. This seems to me to be a fudge, relying on an invisible entity (space). How do you determine experimentally whether space itself is expanding or the stars are moving apart?

MiHsC provides the beginnings of a different view on this. If you modify the inertial mass using both Special Relativity (SR) and MiHsC you get a formula for accelerationa, a, like this: a = F/m*(1-v^2/c^2) + 2c^2/Theta. The first term says that if v=c, no matter what force F you apply you won't get an acceleration from that term. This is why SR precludes crossing the light barrier. However, the new second term from MiHsC says that whatever SR says, there is always a residual minimum acceleration, even when v=c. This is incredibly small: 6.7x10^-10 m/s^2, an acceleration that would produce the speed of light over the age of the universe. A more directly encouraging thing is that it is close to the observed cosmic acceleration.

I submitted a paper on this superlight speculation a couple of years ago to the 100 Year Starship Symposium and another short one a year later to JBIS and haven't heard back from the reviewers yet. Maybe this is because these are a different kind of paper from the ones I normally submit. I tend to only submit papers when I have some experimental data to back the ideas up. With these superlight papers the best I can do so far is say: MiHsC works here and here, and if you extrapolate to the speed of light it predicts a residual acceleration that is close to the cosmic acceleration. This is not an unambiguous test, and the spectre of causality looms large in this area. Anyway, the closest I've got to publishing this so far is a discussion of 'minimum accelerations' in this paper (published in EPL, 90, 29001).

By the way, well done to the Russians. they've just launched a 6 hour fast-track Soyuz to the ISS. I think the Russians have a good attitude to space that could be summarised as: "To the stars, by just doing it."