The Event Horizon Telescope has made what was inferred visible, processing prodigious volumes of radio data to image a black hole in the constellation Virgo.Black holes, with gravitational fields so powerful that not even light could escape them, were inferred by quantum physics about a century ago. Albert Einstein did not like them much, since they represented the frontier of the knowable, where his physics broke down. Beyond the event horizon of a black hole, where matter and energy vanish into a gravity well, stretches a singularity, an area of darkness from where the familiar categories of space, time, matter and information become unrecoverable. But now, the Event Horizon Telescope has made what was inferred visible, processing prodigious volumes of radio data to image a black hole in the constellation Virgo. It is anti-climactic, because black holes have been familiar to us for so very long. And it is a stirring moment for the same reason, because we had never seen one before. Even if the picture that has been published resembles a fried egg in reverse, dark side up.
This is a great scientific achievement, but its success owes to good management rather than pathbreaking science. The Event Horizon Telescope is actually a virtual machine, a network of eight radio telescope arrays scattered all over the earth, which were synchronised in 2017 to look at the same spot in the heavens, 55 million light years away. The mechanics of looking deep into the gulf of space was understood over two decades ago, but the possibility of sharing funds across the European Union helped, as the lead scientists pointed out, as well as the ability to network with installations the world over. The giant leap that has been achieved in data storage and processing in recent years was also a factor. Inured as we are to our embarrassing science congresses, where the properties of prehistoric flying machines and the misunderstood triumphs of ancient surgeons get more attention than real science, it is reassuring to see that this is an aberration.
What next? Science fiction celebrates black holes as gateways into “wormholes”, shortcuts across the universe that bend space-time. Step into one black hole, step out of another 55 million light years away. Of course, the first step is the hardest. An object crossing the event horizon of a black hole would suffer acceleration and tidal forces that should end its career as matter. A black hole is only a shortcut to the sobering realisation that the laws of physics, which we regard to be immutable, are anything but.
