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arXiv · 1308.5611

Discovery of periodic modulations in the optical spectra of galaxies, possibly due to ultra-rapid light bursts from their massive central black hole

Abstract

A Fourier transform analysis of 2.5 million spectra in the SDSS survey was carried out to detect periodic modulations contained in their intensity versus frequency spectrum. A statistically significant signal was found for 223 galaxies while the spectra of 0.9 million galaxies were observed. A plot of the periods as a function of redshift clearly shows that the effect is real without any doubt, because they are quantized at two base periods that increase with redshift in two very tight parallel linear relations. I suggest that it could be caused by light bursts separated by times of the order of 10-13 seconds because it was the original reason for searching for the spectral periodicity but other causes may be possible. As another possible cause, I investigate the hypothesis that the modulation is generated by the Fourier transform of spectral lines, concluding that it is not valid. Although the light bursts suggestion implies absurdly high temperatures, it is supported by the fact that the Crab pulsar also has extremely short unresolved pulses (<0.5 nanosecond) that also imply absurdly high temperatures. Furthermore, the radio spectrum of the Crab pulsar also has spectral bands similar to those that have been detected. Finally, decreasing the signal to noise threshold of detection gave results consistent with beamed signals having a small beam divergence, as expected from non-thermal sources that send a jet, like those seen in pulsars. Considering that galaxy centers contain massive black holes, exotic black hole physics may be responsible for the spectral modulation. However, at this stage, this is only a hypothesis to be confirmed with further work.

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BibTeXRIS

Ermanno F. Borra. 2013-08-26. Discovery of periodic modulations in the optical spectra of galaxies, possibly due to ultra-rapid light bursts from their massive central black hole. https://doi.org/10.1088/0004-637x%2F774%2F2%2F142

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