This week’s news reports highlighting the discovery of the “strongest evidence yet” of life on a distant planet, K2-18b, raise a number of pertinent questions. If life is confirmed there, what would be the next step? Should humans try to establish some sort of contact with these extraterrestrials once we know where they are?

The reports stem from a new paper based on the James Webb Space Telescope (JWST)’s detection of the spectral fingerprint of a single molecule, dimethyl sulfide, in the atmosphere of the exoplanet — that is, a planet which exists outside our solar system. This molecule is not a reliable biomarker according to another paper from earlier this year, which shows that it is found in the interstellar medium without the presence of life. On Earth, this molecule is produced by microorganisms in the oceans.

Inferences based on the detection of molecular biomarkers in the atmospheres of exoplanets are indirect. However, the detection of molecules associated with industrial pollution, such as chlorofluorocarbons (CFCs), will be far more indicative of intelligent life.

If we ever conclusively discover life on an exoplanet, we should definitely listen to any technological signals it transmits. But a dialogue would be challenging. K2-18b is 124 light years away: if we send a communication signal towards it right now, the earliest time we would receive a response at the speed of light would be in the year 2273. Humans, of course, are not that patient, and would love to learn more about the exoplanet through observation over the next two and half centuries.

The K2-18b reports coincide with another arresting bit of news, this time involving Michael Kratsios, the new director of the Office of Science and Technology Policy (OSTP) in the White House. On Monday Kratsios gave his first public talk in the role, remarking that “our technologies permit us to manipulate time and space.” This statement was part of a broader discussion on how regulatory frameworks since the Seventies have potentially hindered technological advancements, in which Kratsios suggested a wider reevaluation to enhance American productivity and innovation. Does this point to the US government possessing secret knowledge about how to manipulate spacetime, garnered from years of reverse engineering of alien spacecraft recovered on Earth?

The field equations formulated by Albert Einstein in 1915 may provide some answers to this troubling question. These equations relate the curvature of spacetime on their left-hand side to the mass or energy density of matter or radiation on their right-hand side. The distortions of time or space are minuscule unless one concentrates a huge amount of mass within a small volume. For example, the Sun distorts spacetime at a minuscule level of one part in 10^8 at the position of Earth. The resulting tiny curvature is sufficient to make the Earth move in a circle around the Sun.

When black holes with tens of solar masses collide at cosmological distances, they produce small ripples in spacetime near Earth, as first detected by the Laser Interferometer Gravitational-Wave Observatory (Ligo) in 2015. The immediate vicinity of black holes is characterised by large spacetime distortions, but the US government does not have access to such environments. We use Einstein’s equations to acquire precise navigation with GPS systems; if these equations were wrong, we would get lost.

What’s more, any experimentation by the US government does not reach the energy densities accessible at the European Organization for Nuclear Research (Cern)’s Large Hadron Collider by many orders of magnitude. This implies that if there is any new physics regarding the manipulation of spacetime, it would have been noticed in unclassified data shared by the international community of physicists at Cern. Secrets were leaked out of the Manhattan Project, and physicists worldwide would have known of any major advance in the theory of gravity.

If we ever learn how to bottle the “dark energy” which causes the accelerated expansion of the universe, we might have access to repulsive — as opposed to attractive — gravity that could propel a craft without fuel. Discovering a more advanced civilisation with this knowledge would unleash a new wave of American innovation, in line with Kratsios’s ambitions. But we have to find these alien technologies first. For that to happen, Nasa needs to allocate billions of dollars to the search for extraterrestrial technosignatures, rather than just investing in biosignatures. Hopefully, someone out there is listening.

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