This question has plagued scientists for decades – if there are extraterrestrials out there, why haven’t they visited Earth yet?
Now scientists think they may have the answer to what is known as the Fermi Paradox.
dr Michael Wong from the Carnegie Institution for Science and Dr. Stuart Bartlett of the California Institute of Technology claim that extraterrestrial civilizations could become so large and technological that they reach crisis points and miss the chance to visit new worlds.
dr Michael Wong from the Carnegie Institution for Science and Dr. Stuart Bartlett of the California Institute of Technology claim that extraterrestrial civilizations are getting so big that they are reaching hot spots and missing the chance to visit new worlds
Is there extraterrestrial life?
Life has never been found outside of Earth; There is no evidence that extraterrestrial life has ever visited our planet.
However, according to NASA, this does not mean that the universe is lifeless outside of Earth.
The space agency says: “Although no definite signs of life have ever been discovered, the possibility of extraterrestrial biology – the scientific logic that supports it – has become increasingly plausible.”
A popular school of thought is that our own existence is evidence that there certainly is life on other planets, since the probability of Earth being a “one-off” is almost zero.
However, one argument against this is: if extraterrestrial life exists, why haven’t we found evidence for it?
The Fermi Paradox asks why there is no sign of extraterrestrial life given the estimated 200 to 400 billion stars and at least 100 billion planets in our galaxy.
The contradiction is named after its creator, Italian physicist Enrico Fermi, who first posed the question back in 1950.
In a new study published in Royal Society Open Science, Drs. Wong and Dr. Bartlett set out to crack the 70-year-old mystery.
The pair analyzed previous studies that had shown that, thanks to their social nature, cities grow “superlinearly” — faster than linearly.
This superlinear scaling leads to crises called “singularities” where population and energy demands crowd out innovation, leading to system collapse.
For example, the researchers say that ozone depletion, the escalation of weapons of mass destruction, and whaling on Earth could have led to burnout if not mitigated.
The researchers assume that burnout will probably also occur in extraterrestrial civilizations.
“We envision that once a planetary civilization transitions to a state that can be described as a virtually connected global city, it faces an ‘asymptotic burnout,’ an ultimate crisis where the singularity interval timescale shrinks than the timescale of innovation,’ they wrote.
If extraterrestrial civilizations can see that they are heading towards this burnout, they may be able to make changes to prevent it and achieve a “homeostatic reorientation”.
If extraterrestrial civilizations can see that they are heading towards this burnout, they may be able to make changes to prevent it, the researchers added.
However, this re-prioritization of resources could make the extraterrestrial civilizations even more difficult to spot.
“We propose a new solution to the Fermi paradox: Civilizations either collapse through burnout or realign to prioritize homeostasis, a state where cosmic expansion is no longer a goal, making it difficult to get them out of the seen from afar,” the team wrote.
As civilizations on the brink of burnout, they might be the closest we’ll see to them, according to the team.
“They would change their environment and consume free energy in totally unsustainable ways — planetary-scale fluctuations that have the largest signal-to-noise ratio.
“This raises the possibility that many of humanity’s first discoveries of extraterrestrial life could be of the intelligent, if not yet wise, kind.
“Observing such burnouts (assuming humanity lives long enough for them) would potentially confirm part of our hypothesis.”
The researchers stress that their study is merely a hypothesis and more research is needed to prove their theory.
“The aim of this article is simply to present the burnout awakening hypothesis and stimulate discussion, introspection, and future work,” they concluded.
“Like so many other astrobiological hypotheses, there is no evidence to date that this idea is true, other than that it is rooted in the laws of life that appear to govern biological organization on Earth.”
The study comes shortly after researchers at Beijing Normal University estimated how long it might take to actually make contact with extraterrestrials.
At best, it could be around two millennia, while a pessimistic view is much longer – 400,000 years to be exact.
“As the only advanced intelligent civilization on Earth, one of the most puzzling questions people face is whether our existence is unique,” authors Wenjie Song and He Gao write in their study.
“The reason why we didn’t receive a signal could be that the human communication lifespan is currently not long enough.”
WHAT IS THE FERMI PARADOX?
The Fermi Paradox asks why there is no sign of extraterrestrial life given the estimated 200 to 400 billion stars and at least 100 billion planets in our galaxy.
The contradiction is named after its creator, the Italian physicist Enrico Fermi.
He first asked the question in 1950.
Fermi thought it too extraordinary that a single extraterrestrial signal or engineering project in the universe had not yet been discovered, despite its immense vastness.
Fermi concluded that there must be a barrier limiting the rise of intelligent, self-aware, technologically advanced, space-populating civilizations.
This barrier is sometimes referred to as the “Big Filter”.
The Italian physicist Enrico Fermi developed the so-called Fermi paradox in the 1950s. It examines why, despite the 100 billion planets in our galaxy, there is no sign of extraterrestrial life
If the main obstacle preventing colonization of other planets does not lie in our past, then the barrier preventing humanity from reaching other worlds must lie in our future, scientists have theorized.
Professor Brian Cox believes that the advances in science and technology needed for a civilization to begin conquering the stars will ultimately lead to their destruction.
He said: “One solution to the Fermi Paradox is that it is not possible to run a world that has the power to self-destruct and that needs global collaborative solutions to prevent it.
“It may be that the growth of science and technology will inevitably outstrip the development of policy expertise, leading to disaster.”
Other possible explanations for the Fermi Paradox are that no other intelligent species have arisen in the universe, that intelligent extraterrestrial species are out there – but do not have the necessary technology to communicate with Earth.
Some believe that the distances between intelligent civilizations are too great to allow any kind of two-way communication.
When two worlds are thousands of light-years apart, it is possible that one or both civilizations will die out before dialogue can be established.
The so-called zoo hypothesis claims that there is intelligent extraterrestrial life out there, but deliberately avoids all contact with life on Earth to allow for its natural evolution.