In 1962, the legendary physicist and mathematician Freeman Dyson wrote a fascinating scientific study that he never published and that has remained hidden until now. In it he postulated the possibility that an extraterrestrial civilization had built a titanic machine capable of converting gravitational waves into energy. In his study, which has just been published posthumously after its author gave his approval before his death, Dyson also explains how we could look for the footprint of this technology to detect such intelligent species in our galaxy. Dyson argues that, given the vast size and age of the universe, it is possible that extraterrestrial civilizations exist that have reached the level of technological development necessary to obtain the resources and tools to build these structures on an astronomical scale.
Gravitational waves originally imagined by Albert Einstein in the mid-20th century and confirmed in 2015 by the LIGO and Virgo experiments are disturbances in the fabric of space-time that propagate through the cosmos at the speed of light. They are caused by massive and extremely violent cosmic events, such as the merger of two neutron stars or two black holes.
The Ligo experiment
Reading that last thought, we might assume that such machines are not worth building but Dyson offers two reasons why it makes sense to consider that a superior civilization would have built such a device. First, if this civilization expands its population and technological level at an exponential rate, there may come a time in the distant future when engineering on an astronomical scale is not only feasible but absolutely necessary in order to power the energy needs of this gigantic interplanetary civilization.
The Dyson Sphere
Dyson’s study is theoretical and, logically, does not provide direct evidence for the existence of these gravitational machines but uses logic and what we know of the universe to postulate their possible existence. a theoretical megastructure that an advanced civilization could build around a star to capture as much of its energy as possible to become a level 2 civilization on the Kardashev scale, the technological barometer proposed by the Soviet physicist in 1964. According to Kardashev, a civilization capable of harnessing all the energy of its star would be level 2. Level 1 is to harness all the possible energy of the civilization’s planet and level 3 can capture all the energy of a galaxy. To reach level 2 you would need several of these gravitational machines, currently, humanity is at level 0.
In February of last year, astronomers identified 260 stars in the Milky Way galaxy that show signs of possible Dyson spheres, making them candidates for hosting planets with advanced extraterrestrial life. But Dyson spheres, like gravitational machines, are purely theoretical and we don’t yet have any direct evidence of their existence. And while these ideas may seem far-fetched and even fantastic, they remind us that our knowledge of the universe is limited and that there is always room for new ideas and discoveries.