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According to the ScienceAlert article Mysterious repeating radio signals have been detected coming from outside our galaxy, based on the Letter to Nature "A repeating fast radio burst", there has been a series of signals detected that the article reports that scientists have not seen before. From the article:

Astronomers have detected repeating blasts of radio signals coming from deep space. These short-lived signals are known as 'fast radio bursts' (FRBs), and although we've heard them before, they were always thought to be one-off events coming from random locations. But for the first time ever, researchers have now heard repeating signals, all emanating from a single unknown source outside our galaxy.

Emphasis mine

In the Letter to Nature, it is hypothesised that the source could be that

these repeat bursts with high dispersion measure and variable spectra specifically seen from the direction of FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star

This leads me to the question:

How could a neutron star cause repeated 'fast radio bursts' detected coming from outside of the galaxy?

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  • $\begingroup$ Neutron Star, I choose you! use Rapid Spin aim towards Earth... [accelerating charged particles emits photon(see synchrotron radiation) and although the beam is pointed towards Earth it's suffers from axial tilt syndrome BTW it isn't 100% neutron.] $\endgroup$ – user6760 Dec 27 '16 at 4:05
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The progenitors of FRBs have been tied to soft gamma-ray repeaters (SGRs), and are likely young magnetars displaying irregular atmospheric and magnetic activity. The earliest connection between the two - as far as I know - was made by Lyutikov (2002), who compared the outbursts to solar flares (the magnetar bursts are sometimes referred to as "giant pulses"), based on models by Thompson et al. (2002).

The theory is that currents dissipate into the neutron star's magnetosphere, at rates coupled to the star's crust. Slow deformation can allow dissipation to proceed at a constant rate, while "fractures" in the crust can lead to quick outbursts. The release of magnetic energy through reconnection may then be responsible for the radio outbursts. The evolution of the field is similar to the behavior of the Sun's magnetic field in the corona, leading to the analogy to solar flares.

Popov & Postner (2007) state that Lyutikov's model's predictions agree with several observed bursts. While the arXiv version of the Letter concerning FRB 121102 does not specifically delve into the model, it seems to support it, although there are doubts as to the feasibility of repeated giant flares.

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