The reactions to the potential discovery depend on whether the person can imagine some explanation for the finding or not. In the latter case the reaction is denial: most physics bloggers have chosen this option for understandable reasons. What else could they do? The six sigma statistics does not leave much room for objections but there could of course be some very delicate systematical error involved. Lubos wrote quite an interesting piece about possible errors of this kind and classified the possible errors to timing errors either at CERN or Italy or to errors in distance measurement.
The neutrinos are highly relativistic having average energy 17 GeV much larger than the mass scale of neutrinos of order .1 eV. The distance between CERN and Gran Sasso is roughly 750 km, which corresponds to the time of travel equal to T=2.4 milliseconds. The nasty neutrinos arrived to Gran Sasso &Delta T=60.7+/-6.9 (statistical) +/-7.4 (systematic) ns before they should have done so. This time corresponds to a distance Δ L= 18 m. From this is is clear that the distance and timing measurements must be extremely accurate. The claimed distance precision is 20 cm (see this.
Experimentalists tell that they have searched for al possible systematic errors that they are able to imagine. The relative deviation of neutrino speed from the speed of light is (c-v)/v= (5.1+/- 2.9)×10-5 which is much larger than the uncertainty related to the value of the speed of light. The effect does not depend on neutrino energy. 6.1 sigma result is in question (for sigmas see this) so that it can be a statistical fluctuation with probability of 10-9 in the case that there is no systematic error.
I already wrote about TGD based explanation of the effect assuming that it is real. The tachyonic explanations of the finding fail because different tachyonic mass is required to explain SN1987A and recent anomaly and other similar anomalies. Tachyons are of course also in conflict with causality. I repeat here the main points here and andd some new points that have emerged in numerous email discussions and blog discussion in viXra log.
- It is sub-manifold geometry which allows to fuse the good aspects of both special relativity (the existence of well-defined conserved quantities due to the isometries of imbedding space) and general relativity (geometrization of gravitation in terms of the induced metric). As an additional bonus one obtains a geometrization of the electro-weak and color interactions and of standard model quantum numbers. The choice of the imbedding space is unique. The new element is the generalization of the notion of space-time: space-time identified as a four-surface has shape as seen from the perspective of the imbedding space M4×CP2. The study of field equations leads among other things to the notion of many-sheeted space-time.
- For many-sheeted space-time light velocity is assigned to light-like geodesic of space-time sheet rather than light-like geodesics of imbedding space M4×CP2. The effective velocity determined from time to travel from point A to B along different space time sheets is different and therefore also the signal velocity determined in this manner. The light-like geodesics of space-time sheet corresponds in the generic case time-like curves of the imbedding space so that the light-velocity is reduced from the maximal signal velocity.
- For Robertson-Walker cosmology imbedded as 4-surface (this is crucial!) in M4×CP2 (see this) the light velocity would be about 73 per cent from the maximal one which would be along light-like geodesics of M4 factor as the simple estimate of the previous posting demonstrates.
This leaves a lot of room to explain various anomalies (problems with determination of Hubble constant, apparent growth of the Moon-Earth distance indicated by the measurement of distance by laser signal,....). The effective velocity can depend on the scale of space-time sheet along which the relativistic particles arrive (and thus on distance distinguishing between OPERA experiment and SN1987A), it can depend on the character of ultra relativistic particle (photon, neutrino, electron,...), etc. The effect is testable by using other relativistic particles -say electrons.
- The energy independence of the results fits perfectly with the predictions of the model since the neutrinos are relativistic. There can be dependence on length scale: in other words distance scale and this is needed to explain SN1987A -CERN difference in Δ c/c. For SN1987A neutrinos were also relativistic and travelled a distance is L=cT=168,000 light years and the neutrinos arrived about Δ T=2-3 hours earlier than photons (see this). This gives Δ c/c = Δ T/T≈ .8-1.2 ×10-6 which is considerably smaller than for the recent experiment. Hence the tachyonic model fails but scale and particle dependent maximal signal velocity can explain the findings easily.
- The space-time sheet along which particles propagate would most naturally correspond to a small deformation of a "massless extremal" ("topological light ray", see this) assignable to the particle in question. Many-sheeted space-time could act like a spectroscope forcing each (free) particle type at its own kind of "massless extremal". The effect is predicted to be present for any relativistic particle. A more detailed model requires a model for the propagation of the particles having as basic building bricks wormhole throats at which the induced metric changes its signature from Minkowskian to Euclidian: the Euclidian regions have interpretation in terms of lines of generalized Feynman graphs. The presence of wormhole contact between two space-time sheets implies the presence of two wormhole throats carrying fermionic quantum numbers and the massless extremal is deformed in the regions surrounding the wormhole throat. At this stage I am not able to construct detailed model for deformed MEs carrying photons, neutrinos or some other relativistic particles.
If I were a boss at CERN, I would suggest that the experiment would be carried out for relativistic electrons whose detection would be much easier and for which one could use much shorter scale.
- Could one use both photon and electron signal simultaneously to eliminate the need to measure precisely the distance between points A and B.
- Can one imagine using mirrors for photons and relativistic electrons and comparing the times for A→ B→ A?
As a matter fact, there is an old result by electric engineer Obolensky that I have mentioned earlier (see this), and which states that in circuits signals seem to travel at superluminal speed. The study continues the tradition initiated by Tesla who started the study of what happens when relays are switched on or off in circuits.
- The experimental arrangement of Obolensky suggest that that part of circuit - the base of the so called Obolensky triangle- behaves as a single coherent quantum unit in the sense that the interaction between the relays defining the ends of the base is instantaneous: the swithing of the relay induces simultaneously a signal from both ends of the base.
- There are electromagnetic signals propagating with velocities c0(with values 271 +/- 1.8× 106 m/s and 278 +/- 2.2× 106 m/s) and c1 (200.110× 106 m/s): these velocities are referred to as Maxwellian velocities and they are below light velocity in vacuum equal to c=3× 108 m/s. c0 and c1 would naturally correspond to light velocities affected by the interaction of light with the charges of the circuit.
- There is also a signal propagating with a velocity c2 ((620+/- 2.7) × 106 m/s), which is slightly more than twice the light velocity in vacuum. Does the identification c2=cmax, where cmax is the maximal signal velocity in M4× CP2, make sense? Could the light velocity c in vacuum correspond to light velocity, which has been reduced from the light velocity c#= .73 cmax in cosmic length scales due to the presence of matter to c#=.48cmax. Note that this interpretation does not require that electrons propagate with a super-luminal speed.
- If Obolensky's findings are true and interpreted correctly, simple electric circuits might allow the study of many-sheeted space-time in garage!
To conclude, if the finding turns out to be true it will mean for TGD what Mickelson-Morley meant for special relativity.
Addition: Those string theorists are simply incredible. Here is This Week's hype which appeared in New Scientist.
So if OPERA’s results hold up, they could provide support for the existence of sterile neutrinos, extra dimensions and perhaps string theory. Such theories could also explain why gravity is so weak compared with the other fundamental forces. The theoretical particles that mediate gravity, known as gravitons, may also be closed loops of string that leak off into the bulk. “If, in the end, nobody sees anything wrong and other people reproduce OPERA’s results, then I think it’s evidence for string theory, in that string theory is what makes extra dimensions credible in the first place,” Weiler says.
This is absolute nonsense. What is wrong in physics community: why lying has become everyday practice?
Addition: From the comment section in Peter Woit's blog I learned that M-theorists have already represented a direct modification of the TGD explanation for neutrino super-luminality by replacing space-time surfaces with branes: web is a very effective communication tool;-). My guess was that the "discovery" takes place within a week. I would not be surprised if neutrino super-luminality would become the last straw for drowning M-theory. Sad that we must still tolerate a decade M-theoretic non-sense.