Are we alone in the universe? Three Oxford academics conclude that probably yes | Science and Health

This is the question that the famous Italian physicist Enrico Fermi asked his colleagues while he was working at the National Laboratory of Los Alamos in the United States in 1950.

Fermi discussed the Existence of other intelligent civilizations and the apparent contradiction between believes that there is a high probability that these civilizations exist in the observable universe – and the lack of evidence of their existence.

Only in the Milky Way, the most conservative estimate indicates the existence of about 100 billion stars, many of which are surrounded by planets. Why, then, do not we still have proof of intelligent life beyond our planet?

There are billions of possibilities for intelligent civilizations, why has no one tried to get in touch?

This disparity, known as the Fermi Paradox, was re-evaluated by three researchers at Oxford University.

And in their study, titled Dissipate the Fermi Paradox, they say that humanity is more likely to be "alone in the universe."

The three authors of the study are Anders Sandberg, a researcher at the Future Institute of Humanity at Oxford University, Eric Drexler, who popularized the concept of nanotechnology, and Tod Ord, professor from philosophy to the same academic center.

Their new work badyzes one of the mathematical underpinnings of Fermi's paradox, the Drake equation proposed by astronomer Frank Drake in the 1960s.

The equation has designed to estimate the number of detectable civilizations in the Milky Way and multiply seven variables.

Two of them, for example, are N, the number of Milky Way civilizations whose electromagnetic emissions are detectable, and fp, the fraction of stars with planetary systems.

The three Oxford researchers presented an updated version of the Drake equation that incorporates "a more realistic distribution of uncertainty".

The Drake equation has been used in the past to show that the number of possible places where there might be life should produce a large number of civilizations.

But these applications badume "a certainty about the highly uncertain parameters," emphasize the study's authors.

"We examine these parameters by integrating models of chemical and genetic transitions along the pathways leading to the origin of life, and show that existing scientific knowledge corresponds to uncertainties extending over several orders of magnitude. " Sandberg and his colleagues.

Examining the equation with more realistic distributions of uncertainty led the authors to conclude that "there is a 39 to 85% probability that humans be alone in the universe ".

"We find a substantial probability that there is no other intelligent life in our observable universe, and as a result, there should be no surprises when we do not have a good life. detect any sign, "say the authors.

The greater uncertainty "leads us to conclude that there is a rather high probability of being alone," they say.

The authors of the study do not believe however that scientists should give up seeking extraterrestrial intelligence or SETI, to from the acronym English.

Recently, for example, scientists have discovered the existence of complex carbon-based molecules in the waters of Enceladus, a moon of Saturn, which may indicate that the place is capable of to house life – something that will only be bought after several years research.

"We do not show that this quest (for extraterrestrial life) is useless, on the contrary," said Sandberg. "The level of uncertainty that we need to reduce is enormous and astrobiology and SETI can play an important role in reducing this uncertainty of certain parameters."

There are no simple answers to the Fermi paradox.