An EPFL scientist has developed a novel approach that boosts the chances of finding extraterrestrial intelligence in our galaxy. His method uses probability theory to calculate the possibility of detecting an extraterrestrial signal (if there is one) at a given distance from Earth.
Could there be another planet out there with a society at the same stage of technological advancement as ours? To help find out, EPFL scientist Claudio
Grimaldi, working in association with the University of California, Berkeley, has developed a statistical model that gives researchers a new tool in the search for the kind of signals that an extraterrestrial society might emit. His method – described in an article appearing today in PNAS* – could also make the search cheaper and more efficient.
Astrophysics initially wasn’t Grimaldi’s thing; he was interested more in the physics of condensed matter. Working at EPFL’s Laboratory of Physics of Complex Matter, his research involved calculating the probabilities of carbon nanotubes exchanging electrons. But then he wondered: if the nanotubes were stars and the electrons were signals generated by extraterrestrial societies, could we calculate the probability of detecting those signals more accurately?
This is not pie-in-the-sky research – scientists have been studying this possibility for nearly 60 years. Several research projects concerning the search for extraterrestrial intelligence (SETI) have been launched since the late 1950s, mainly in the United States. The idea is that an advanced civilization on another planet could be generating electromagnetic signals, and scientists on Earth might be able to pick up those signals using the latest high-performance radio telescopes.
Despite considerable advances in radio astronomy and the increase in computing power since then, none of those projects has led to anything concrete. Some signals have been recorded, like the Wow! signal in 1977, but scientists could not pinpoint their origin. And none of them has been repeated or seems credible enough to be attributable to alien life.
But that doesn’t mean scientists have given up. On the contrary, SETI has seen renewed interest following the discovery of the many exoplanets orbiting the billions of suns in our g alaxy. Researchers have designed sophisticated new instruments – like the Square Kilometre Array, a giant radio telescope being built in South Africa and Australia with a total collecting area of one square kilometer – that could pave the way to promising breakthroughs. And Russian entrepreneur Yuri Milner recently announced an ambitious program called Breakthrough Listen, which aims to cover 10 times more sky than previous searches and scan a much wider band of frequencies. Milner intends to fund his initiative with 100 million dollars over 10 years.
“In reality, expanding the search to these magnitudes only increases our chances of finding something by very little. And if we still don’t detect any signals, we can’t necessarily conclude with much more certainty that there is no life out there,” says Grimaldi.
Still a ways to go
The advantage of Grimaldi’s statistical model is that it lets scientists interpret both the success and failure to detect signals at varying distances from the Earth. His model employs Bayes’ theorem to calculate the remaining probability of detecting a signal within a given radius around our planet. For example, even if no signal is detected within a radius of 1,000 light years, there is still an over 10% chance that the Earth is within range of hundreds of similar signals from elsewhere in the galaxy, but that our radio telescopes are currently not powerful enough to detect them. However, that probability rises to nearly 100% if even just one signal is detected within the 1,000-light-year radius. In that case, we could be almost certain that our galaxy is full of alien life.
After factoring in other parameters like the size of the galaxy and how closely packed its stars are, Grimaldi estimates that the probability of detecting a signal becomes very slight only at a radius of 40,000 light years. In other words, if no signals are detected at this distance from the Earth, we could reasonably conclude that no other civilization at the same level of technological development as ours is detectable in the galaxy. But so far, scientists have been able to search for signals within a radius of “just” 40 light years.
So there’s still a ways to go. Especially since these search methods can’t detect alien civilizations that may be in primordial stages or that are highly advanced but haven’t followed the same technological trajectory as ours.
Receive an email update when we add a new SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE article.
The Latest on: Search for extraterrestrial intelligence
via Google News
The Latest on: Search for extraterrestrial intelligence
- New Tool Helps Target The Search For Alien Life on November 7, 2018 at 4:13 pm
Several research projects concerning the search for extraterrestrial intelligence (SETI) have been launched since the late 1950s, mainly in the United States. The idea is that an advanced civilization ... […]
- Purple planets, alien probes and a cosmic hot tub: Search for extraterrestrials goes in new directions on November 7, 2018 at 11:50 am
Over the past few months, the U.S. Congress has been considering whether it should again start funding the Search for Extraterrestrial Intelligence project, better known as SETI, reversing 25 years of ... […]
- NASA Expert to Discuss Search for Extraterrestrials, Interstellar Space Travel at The Optical Society Laser Congress on November 1, 2018 at 1:16 pm
and the search for extraterrestrial intelligence (SETI). “Our primary focus currently is on very small robotic spacecraft. They won’t carry humans onboard—it’s not the goal for the ... […]
- How SETI uses off-the-shelf AI to search for extraterrestrial life on October 23, 2018 at 6:25 pm
The Search for Extraterrestrial Intelligence Institute (SETI) is using off-the-shelf machine learning technology from Nvidia and Google to advance its mission of finding other forms of life in the uni... […]
- How Paul Allen Saved the American Search for Extraterrestrial Intelligence on October 16, 2018 at 3:55 pm
On Monday evening, Microsoft co-founder Paul Allen died of non-Hodgkin's lymphoma at the age of 65. At the time of his death, Allen was the 47th richest person in the world, with a net worth of $26 bi... […]
- Paul Allen dead at 65, but his projects live on — including a search for E.T. on October 15, 2018 at 7:00 pm
connected to an incredibly powerful network of computers and listening to the radio sounds of the universe in the SETI Institute's search for extraterrestrial intelligence. Download the Microsoft News ... […]
- In Our Time Topics - Search for extraterrestrial intelligence on September 15, 2018 at 5:00 pm
Melvyn Bragg and his guests discuss planets outside our solar system, known as exoplanets. Melvyn Bragg and guests discuss our chances of ever discovering life on another planet. […]
- We Should Search for Aliens by Looking for Their Space Junk on June 8, 2018 at 1:10 pm
Advertisement The search for extraterrestrial intelligence (SETI) began in earnest in the 1960s when scientists started scanning for alien radio signals. This approach has yielding nothing, highlighti... […]
- 'Search for Extraterrestrial Intelligence' Needs a New Name, SETI Pioneer Says on January 29, 2018 at 4:00 pm
IRVINE, Calif. — Astrophysicist Jill Tarter is one of the world's best-known leaders in the search for extraterrestrial intelligence, or SETI. For 35 years, she served as the director of the Center fo... […]
via Bing News