Surprising finding about gamma ray bursts
I received an interesting link (thanks to Ulla) about "too high" circular polarization observed for gamma radiation arriving from the after glow assignable to the afterglow of gamma ray burst assignable to a shockwave in the proposed models (see this). The amount of energy emitted in the bursts is gigantic if the emission takes place in all directions.
- I have proposed a model for gamma ray bursts based on magnetic flux identified as thickened cosmic strings in which the emission takes along the flux tube and is detected only if the flux tubes happens to intersect the region where the radiation is detected. Magnetic energy would be liberated as gamma ray burst. As a matter fact, all particles would have resulted in the decay of this magnetic energy assignable to monopole flux carrying flux tubes and taking the role of the dark energy in TGD.
- What would be the mechanism liberating the magnetic energy? This is the key question to be answered if one assumes that ordinary matter results from the dark energy identifiable as the magnetic energy of flux tubes. Something happens to the flux tube: the natural assumption is that it gets thicker since this process occurring repeatedly would gradually lead to the recent relatively weak values of magnetic fields.
Flux must be conserved in the process. If the p-adic length scales characterizing the flux tube increases the field strength must scale down like B ∝ 1/L(k)2 so that the field energy density per unit length proportional to B2S, S the cross section of the flux tube, scales down like 1/L(k)2. Magnetic energy is liberated and this would be transformed to the energy of dark photons arriving along the flux tube and transform partially to ordinary photons as they are detected.
Consider now the mechanism possibly generating circular polarization. By looking at Wikipedia one learns that it is not easy to get circularly polarized light by natural mechanisms. For instance, in atmosphere multiple scattering of light can produce small circular polarization and it has been suggested that this circular polarization might have induced chiral selection in biology. Two mechanisms come into mind.
- The first mechanism generating circularly polarized gamma rays did not come first into my mind. Photons could be created as cyclotron photons in the transitions of dark cyclotron electron (say) condensate at the flux tube. If the spin direction of the charged particles is same (spontaneous magnetization) spin flips occur in same direction spin direction and produced photons of definite helicity. The problem is that the polarization would be circular! Could this be a mechanism generating dark circularly polarized photons along the flux tube? This kind of circularly polarized photons could play also a role in the generation of chiral selection in biology.
- What came first to into my non-professional mind was circular dichroism. Circular polarisations have handedness: left or right. The medium in which they move could absorb second handedness more strongly and leave only the other one. [Alternatively, the propagation velocities could differ for two orthogonal directions and this would lead to a phase difference between orthogonal components of linear polarization and thus circular polarization (or elliptic more generally)]. In biology the handedness of bio- molecules is detected by different absorption of left and right polarizations. One can express the linearly polarized light entering to this kind of medium as a superposition of opposite circular polarizations. If second polarization is absorbed more strongly a circular polarization is expected.
There are two difficult questions to be answered and I try to answer these questions by using the TGD based model of chiral selection in living matter and the TGD based model for the gamma ray bursts as a starting point.
- How to obtain the chiral media? Could it be that there are one or more helical magnetic flux tubes with preferred chirality along which the radiations propagates as cyclotron radiation and helicality favors generation of circular polarization just as helical molecules do in living matter? Breaking of chirality analogous to that in living matter is needed: large large enough value of heff=n× h provides it in TGD framework by making possible large parity breaking effect due to weak interactions but in scale which is n times the weak scale of order 10-17 meters.
Weak scale should be scaled up to something like wave length of gamma rays , which should roughly be of the order of the thickness of helical flux tubes. This requires quite a big value of heff/h=n. In biology n=about 1012 would bring weak scale to about 10-5 meters , which corresponds to size scale of cell (in biology this would also predict that dark photons at ELF frequencies have energies in bio-photon range). In fact, this value of n follows if the heff is identified as gravitational Planck constant, which is indeed done in the recent view about dark photons in living matter. The value of heff=h gr for a particle of mass m would be GMm/v0, where M is the mass of bigger object, now perhaps magnetar, m is the mass of particle, and v0< c is a characteristic velocity parameter for the system. hgr depends on particle but gravitational Compton length is same for all particles: a prerequisite for quantum coherence in the scale of R= GMmc/v0, which would represent the size scale of say magnetar. In fact, v0 might be estimated from this condition.
This parity breaking could be analogous to that proposed by experimentalists to occur in heavy ion collisions for what was originally thought to be quark gluon plasma: I wrote a blog posting about this some time ago. I wrote also a posting about chiral selection in living matter. The proposed mechanisms are based also on large heff and dark magnetic flux tubes.
- There is also second problem related to the mechanism involving helical flux tubes. Dimensional magic suggests that the generation of circular polarization is maximal if the wavelength is of same order of magnitude as the thickness of the helical flux tube along which the radiation would arrive. For gamma rays with MeV energy the wavelength is however of order of order 10-12 meters, electron Compton length: this for the ordinary value of Planck constant. Wikipedia mentions magnetic fields strengths of order 1010 Tesla for magnetars also generating gamma ray bursts. If the magnetic flux through the tube is quantized and has minimal value (assuming that flux tubes carries monopole flux, which is possible in TGD Universe and explains the existence of magnetic fields in all scales), the estimate R &asymp: 10-13 meters follows for the radius of the flux tubes. The radius of the helical flux tube could be of course much larger.
- The wavelength is measured in longitudinal direction rather than in transversal direction unless large heff could strengths dark gamma ray photons only in the direction of the flux tube. Flux tube thickness need not be scaled up in h→ heff. The value of the flux quantum is proportional to heff is dictated by flux quantization. By replacing h with h
eff in the unit of flux quantum proportional to Planck constant, the flux quantum scales by n and the radius of the flux tube by n1/2 rather than n.
For heff/h=n the wavelength is scaled up by n and for the values of n suggested by biology n would be of order 1012. One MeV gamma ray wave length would scale up to about .1 meters. The flux tube radius would scale to about 10-7 meters - happens to be a biological scale - 10 times the thickness of DNA coil of 10 nm. Nothing prevents assuming that that the radius of the helix is about .1 meter and thus of the same order of magnitude as wavelength.
The generation of ordinary matter during TGD counterpart of inflationary period is also based on the decay of dark magnetic energy to dark photons. Could a small circular polarization of CMB serve as a signature of this process? I have already earlier considered the possibility that the magnetic fields assignable to the flux tubes could somehow be responsible for linear polarization. The above mechanism would however give circularly polarized component. I do not understand the experimental side: It seems implausible that experiments could fail to detect circular polarization.
To sum up, a possible candidate for the new physics required by the circular polarization of the afterglow would be that of dark matter in TGD sense. According to the earlier proposal, gamma ray bursts could be assigned with with decay of magnetic energy for thickened cosmic strings. The dark photon radiation could be generated at the flux tube or move along a helical thickened cosmic string and helicality could induce the circular polarization. The only justification for this picture is that it fits to the overall vision.