Fermi Paradox Archives

December 5, 2022December 5, 2022 by Andy Tomaswick

Maybe we don’t see Aliens Because They’re Waiting to Hear a Signal From us First

We’ve had a long-running series here at UT on potential solutions Fermi Paradox – why aren’t we able to detect any alien life out there in the Universe? But more possible solutions are being developed all the time. Now, another paper adds some additional theory to one of the more popular solutions – that aliens are just too busy to care about us.

October 25, 2022October 25, 2022 by Evan Gough

Maybe We Don’t See Aliens Because Nobody Wants to Come Here

Artist impression of an alien civilization. Image credit: CfA

The Fermi Paradox won’t go away. It’s one of our most compelling thought experiments, and generations of scientists keep wrestling with it. The paradox pits high estimates for the number of civilizations in the galaxy against the fact that we don’t see any of those civs. It says that if rapidly expanding civilizations exist in the Milky Way, one should have arrived here in our Solar System. The fact that none have implies that none exist.

Many thinkers and scientists have addressed the Fermi Paradox and tried to come up with a reason why we don’t see any evidence of an expanding technological civilization. Life may be extraordinarily rare, and the obstacles to interstellar travel may be too challenging. It could be that simple.

But a new paper has a new answer: maybe our Solar System doesn’t offer what long-lived, rapidly expanding civilizations desire: the correct type of star.

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September 13, 2022September 13, 2022 by Seth Lockman

Alien Artifacts Could Be Hidden Across the Solar System. Here’s how we Could Search for Them.

Galileo Project members (from left: Carson Ezell, Ezra Kelderman, Abby White, Alex and Lily Delacroix) with the audio tower (left), radar spectrum tower (middle) and radar imaging tower (right) behind them on the roof of the Harvard College Observatory. Image credit: The Galileo Project

Do aliens exist? Almost certainly. The universe is vast and ancient, and our corner of it is not particularly special. If life emerged here, it probably did elsewhere. Keep in mind this is a super broad assumption. A single instance of fossilized archaebacteria-like organisms five superclusters away would be all it takes to say, “Yes, there are aliens!” …if we could find them somehow.

July 26, 2022July 26, 2022 by Matt Williams

Before we Develop Self-Replicating Machines to Explore the Universe, we Should Figure out how to Turn Them off Again

An early NASA concept of an interstellar space probe. Credit: NASA/Johns Hopkins University Applied Physics Laboratory

In 1948/49, famed computer scientist, engineer, and physicist John von Neumann introduced the world to his revolutionary idea for a species of self-replicating robots (aka. “Universal Assemblers”). In time, researchers involved in the Search for Extraterrestrial Intelligence (SETI) adopted this idea, stating that self-replicating probes would be an effective way to explore the cosmos and that an advanced species may be doing this already. Among SETI researchers, “Von Neumann probes” (as they’ve come to be known) are considered a viable indication of technologically advanced species (technosignature).

Given the rate of progress with robotics, it’s likely just a matter of time before humanity can deploy Von Neumann probes, and the range of applications is endless. But what about the safety implications? In a recent study by Carleton University Professor Alex Ellery explores the potential harm that Von Neumann Probes could have. In particular, Ellery considers the prospect of runaway population growth (aka. the “grey goo problem”) and how a series of biologically-inspired controls that impose a cap on their replication cycles would prevent that.

March 20, 2022March 20, 2022 by Matt Williams

Why Would an Alien Civilization Send Out Von Neumann Probes? Lots of Reasons, says a new Study

Artist's concept of the New Horizons spacecraft encountering a Kuiper Belt object, part of an extended mission after the spacecraft’s July 2015 Pluto flyby. Credits: NASA/JHUAPL/SwRI

In 1948-49, mathematician, physicist, computer scientist, and engineer John von Neumann introduced the world to his idea of “Universal Assemblers,” a species of self-replicating robots. Von Neumann’s ideas and notes were later compiled in a book titled “Theory of self-reproducing automata,” published in 1966 (after his death). In time, this theory would have implications for the Search for Extraterrestrial Intelligence (SETI), with theorists stating that advanced intelligence must have deployed such probes already.

The reasons and technical challenges of taking the self-replicating probe route are explored in a recent paper by Gregory L. Matloff, an associate professor at the New York City College of Technology (NYCCT). In addition to exploring why an advanced species would opt to explore the galaxy using Von Neumann probes (which could include us someday), he explored possible methods for interstellar travel, strategies for exploration, and where these probes might be found.

November 22, 2021November 24, 2021 by Matt Williams

If Alien Probes are Already in the Solar System, Maybe we Could Detect Them Calling Home

Artist's impression of the Milky Way Galaxy. Credit: ESO

It’s been seventy years since physicist Enrico Fermi asked his famous question: “Where is everybody?” And yet, the tyranny of the Fermi Paradox is still with us and will continue to be until definitive evidence of Extraterrestrial Intelligence (ETI) is found. In the meantime, scientists are forced to speculate as to why we haven’t found any yet and (more importantly) what we should be looking for. By focusing our search efforts, it is hoped that we may finally determine that we are not alone in the Universe.

In a recent study, two researchers from the University of Liège and the Massachusetts Institute of Technology (MIT) recommended that we look for evidence of transmissions from our Solar System. Based on the theory that ETIs exist and have already established a communications network in our galaxy, the team identified Wolf 359 as the best place to look for possible interstellar communications from an alien probe.

October 5, 2021October 17, 2021 by Matt Williams

Beyond “Fermi’s Paradox” XVII: What is the “SETI-Paradox” Hypothesis?

The Arecibo Radio Telescope in Puerto Rico was the site of NASA's High Resolution Microwave Survey, a search for extraterrestrial radio messages. Credit: Unites States National Science Foundation

Welcome back to our Fermi Paradox series, where we take a look at possible resolutions to Enrico Fermi’s famous question, “Where Is Everybody?” Today, we examine the possibility that we haven’t heard from any aliens is because no one is transmitting!

In 1950, Italian-American physicist Enrico Fermi sat down to lunch with some of his colleagues at the Los Alamos National Laboratory, where he had worked five years prior as part of the Manhattan Project. According to various accounts, the conversation turned to aliens and the recent spate of UFOs. Into this, Fermi issued a statement that would go down in the annals of history: “Where is everybody?”

This became the basis of the Fermi Paradox, which refers to the disparity between high probability estimates for the existence of extraterrestrial intelligence (ETI) and the apparent lack of evidence. Since Fermi’s time, there have been several proposed resolutions to his question, including the possibility that everyone is listening, but no one is broadcasting – otherwise known as the “SETI-Paradox.”

September 17, 2021September 17, 2021 by Matt Williams

If Aliens Are Out There, We’ll Meet Them in a Few Hundred Million Years

An artist's conception of how common exoplanets are throughout the Milky Way Galaxy. Image Credit: Wikipedia

Seventy years ago, Italian-American nuclear physicist Enrico Fermi asked his colleagues a question during a lunchtime conversation. If life is common in our Universe, why can’t we see any evidence of its activity out there (aka. “where is everybody?”) Seventy years later, this question has launched just as many proposed resolutions as to how extraterrestrial intelligence (ETIs) could be common, yet go unnoticed by our instruments.

Some possibilities that have been considered are that humanity might be alone in the Universe, early to the party, or is not in a position to notice any yet. But in a recent study, Robin Hanson (creator of the Great Filter) and an interdisciplinary team offer a new model for determining when the aliens will get here. According to their study, humanity is early to the Universe and will meet others in 200 million to 2 billion years from now.

January 7, 2021February 7, 2022 by Matt Williams

Beyond “Fermi’s Paradox” XVI: What is the “Dark Forest” Hypothesis?

The Full Moon at 10:30 p.m. last night (Aug. 30). Even at 25 altitude, it glowed a deep, dark orange due to heavy smoke from western forest fires. Credit: Bob King

Welcome back to our Fermi Paradox series, where we take a look at possible resolutions to Enrico Fermi’s famous question, “Where Is Everybody?” Today, we examine the possibility that Earth hasn’t been visited by aliens because interstellar travel is not very practical!

This became the basis of the Fermi Paradox, which refers to the disparity between high probability estimates for the existence of extraterrestrial intelligence (ETI) and the apparent lack of evidence. Since Fermi’s time, there have been several proposed resolutions to his question, which includes the Dark Forest Hypothesis, where extraterrestrial civilizations are deliberately avoiding contact.

December 25, 2020February 7, 2022 by Matt Williams

Beyond “Fermi’s Paradox” XV: What is the Percolation Theory Hypothesis?

This became the basis of the Fermi Paradox, which refers to the disparity between high probability estimates for the existence of extraterrestrial intelligence (ETI) and the apparent lack of evidence. Since Fermi’s time, there have been several proposed resolutions to his question, which includes the very real possibility that interstellar colonization follows the basic rule of Percolation Theory.