First observed in 2007, fast radio bursts (or FRBs) are random short-lived flashes of radio emission from deep space that last for only a few milliseconds. To date, less than two dozen of these have been detected mostly through powerful radio telescopes such as the Parkes Observatory in Australia and the Arecibo Observatory in Puerto Rico.
Scientists believe that fast radio bursts originate from extremely distant galaxies billions of light years away. Nobody knows, however, what (or who) are causing these.
There have been a few theories, all cosmological in nature, of FRBs coming from gamma-ray bursts, maybe supermassive rapidly spinning or colliding neutron stars, a supernova, or possibly stellar flares. But not a single one of these theories is close to providing an acceptable explanation.
Taking off from this, astrophysicists Avi Loeb of the Harvard-Smithsonian Center for Astrophysics and Manasvi Lingam of Harvard Universty decided that if the explanation isn’t natural, then maybe it was time to delve into the bizarre. As Loeb said in a statement: “Fast radio bursts are exceedingly bright given their short duration and origin at great distances, and we haven’t identified a possible natural source with any confidence. An artificial origin is worth contemplating and checking.”
By ‘artificial origin’ Loeb actually means alien origin, or in other words, FRBs sounds might be coming from a super-powerful alien radio transmitter. Sounds absurd? Well, if the transmitter was supposedly a solar-powered device that’s twice as big as the Earth, it would be powerful enough to generate the energy needed to produce FRBs. Which makes Loeb’s approach feasible given the fact that that kind of colossal size project is way beyond our present technological capabilities. And that simply and logically means that if such device did really exist, and we couldn’t have built it, who else could have done it but aliens, right?
Taking the ‘fantasy/probability’ further, Lingam and Loeb next thought about their theory from an engineering point of view. They questioned whether the structure will be able to withstand such a tremendous amount of energy. Their answer ; if it was water-cooled it would certainly be sufficient to keep a project like this operating.
Then comes the biggest question — what’s the whole point of building such a structure? To drive interstellar light sails, of course. According to the duo, with that amount of power, it will be possible to push millions of tons worth of load. In terms of passengers, it will be big enough to carry loads of them over ‘interstellar or even intergalactic distances’.
So how does all this fit into the search for the origin of FRBs? Theoretically, the interstellar light sail would need a beam that’s perpetually focused on it. This is what the transmitter will do — power the sail with a continuous beam. From our end, all we can see is an occasional brief flash because as the Earth is moving, so is everything else in the universe.
So is it science or science fiction? Loeb’s words: “Science isn’t a matter of belief, it’s a matter of evidence. Deciding what’s likely ahead of time limits the possibilities. It’s worth putting ideas out there and letting the data be the judge.”
The paper detailing the study was published in the Astrophysical Journal Letters.