Dark Forest: Should We NOT Contact Aliens?

444,842
0
Published 2024-03-14
Check out the Space Time Merch Store
www.pbsspacetime.com/shop

In 1974 we sent the Arecibo radio message towards Messier 13, a globular cluster near the edge of the Milky Way, made up of a few hundred thousand stars. The message was mostly symbolic; we weren’t really expecting a reply. Yet surely other civilisations out there are doing the same thing. So, why haven’t we heard anything? What if the silence from the stars is a hint that we shouldn’t be so outgoing? What if aliens are deliberately keeping quiet for fear that they might be destroyed?

Sign Up on Patreon to get access to the Space Time Discord!
www.patreon.com/pbsspacetime

PBS Member Stations rely on viewers like you. To support your local station, go to:to.pbs.org/DonateSPACE

Sign up for the mailing list to get episode notifications and hear special announcements!
mailchi.mp/1a6eb8f2717d/spacetime

Search the Entire Space Time Library Here: search.pbsspacetime.com/

Hosted by Matt O'Dowd
Written by Richard Dyer & Matt O'Dowd
Post Production by Leonardo Scholzer, Yago Ballarini & Stephanie Faria
Directed by Andrew Kornhaber
Associate Producer: Bahar Gholipour
Executive Producers: Eric Brown & Andrew Kornhaber
Executive in Charge for PBS: Maribel Lopez
Director of Programming for PBS: Gabrielle Ewing
Assistant Director of Programming for PBS: John Campbell

Spacetime is a production of Kornhaber Brown for PBS Digital Studios.
This program is produced by Kornhaber Brown, which is solely responsible for its content.
© 2024 PBS. All rights reserved.

End Credits Music by J.R.S. Schattenberg: youtube.com/user/MultiDroideka

Space Time Was Made Possible In Part By:

Big Bang Sponsors
John Sronce
Bryce Fort
Peter Barrett
David Neumann
Alexander Tamas
Morgan Hough
Juan Benet
Vinnie Falco
Mark Rosenthal

Quasar Sponsors
Glenn Sugden
Alex Kern
Ethan Cohen
Stephen Wilcox
Mark Heising

Hypernova Sponsors
Chris Webb
David Giltinan
Ivari Tölp
Kenneth See
Gregory Forfa
drollere
Bradley Voorhees
Scott Gorlick
Paul Stehr-Green
Ben Delo
Scott Gray
Антон Кочков
Robert Ilardi
John R. Slavik
Mathew
Donal Botkin
Edmund Fokschaner
chuck zegar
Jordan Young
Daniel Muzquiz

Gamma Ray Burst Sponsors
Jessica M. Kandal, Ph.D.
Anthony Crossland
Grace Seraph
Frank Plessers
Max Paladino
Stephen Saslow
Robert DeChellis
Tomaz Lovsin
Anthony Leon
Leonardo Schulthais Senna
Lori Ferris
Dennis Van Hoof
Koen Wilde
Nicolas Katsantonis
Joe Pavlovic
Justin Lloyd
Chuck Lukaszewski
Andrea Galvagni
Jerry Thomas
Nikhil Sharma
John Anderson
Bradley Ulis
Craig Falls
Kane Holbrook
Ross Story
teng guo
Harsh Khandhadia
Michael Lev
Terje Vold
James Trimmier
Jeremy Soller
Paul Wood
Joe Moreira
Kent Durham
jim bartosh
John H. Austin, Jr.
Diana S
Faraz Khan
Almog Cohen
Daniel Jennings
Russ Creech
Jeremy Reed
David Johnston
Michael Barton
Isaac Suttell
Oliver Flanagan
Bleys Goodson
Mark Delagasse
Mark Daniel Cohen
Shane Calimlim
Tybie Fitzhugh
Eric Kiebler
Craig Stonaha
Frederic Simon
Tonyface
John Robinson
Jim Hudson
David Barnholdt
John Funai
Adrien Molyneux
Bradley Jenkins
Amy Hickman
Vlad Shipulin
Thomas Dougherty
King Zeckendorff
Dan Warren
Joseph Salomone
Patrick Sutton
Julien Dubois

All Comments (21)
  • @vitorDM682
    There is a problem with the Game Theory logic there, and it's that you assume that any civilization you find will be confined into a single place that CAN be destroyed. In reality, the player must consider that the civilization they detected might be a branch or a colony of a larger civilization they have yet to detect. In other words, the option to "destroy" might also lead to civilization A to respond, but now, their response will not be to ignore or contact, since they KNOW you are aggressive. So the option to destroy is actually the worst, since it guarantees that, unless you are absolutelly sure you are destroying the whole civilization, that retribution wwill be comming your way.
  • @ngwoo
    "The humans are talking about genocide in terms of game theory again, let's keep hiding from them" is a potential variation of the Dark Forest Hypothesis.
  • @alexmangorove
    “ "We" don't decide things. Individuals decide, and collective action emerges in a very complex way.” - This is so well put and so many people don't understand.
  • @Lantalia
    The game is more complicated than indicated, there are multiple alternate plays, the first layer of them being to remove yourself from being a soft target, setup MAD, and doing any talking from something that you can afford to have hit
  • @Thephalex78
    One of the biggest flaw about the destroy option is that if a new player C has chosen the option "silence" they saw B destroy A ... and then migth chose to destroy B by retaliation or fears.
  • @pilliozoltan6918
    The "destroy" option in reality is "try to destroy" and has a branch where it fails and the next step us counterattack with infinite cost. I think that's where this logic fails.
  • @mikotagayuna8494
    This was the reason why we were churning out superhero movies for the past decade. The hope is that any aliens who receive our broadcasts will be duly warned of how often we get invaded and how it always ends for them.
  • Is it coincidence this video came out only a few days before "3 Body Problem" on Netflix, or am I starting to see numbers? I mean, there's been videos on the Fermi paradox before, but damn, that's some timing!
  • @WallOfScience
    The Dark Forest explanation for the Fermi Paradox was also a central plot point of the 1987 novel The Forge of God (and its sequel Anvil of Stars) by author Greg Bear. These are both great books that I highly recommend.
  • @axilmar254
    A simpler and much more reality-based explanation for the great silence is that civilizations are so far away from each other and that physics don't allow for meaningful interstellar communication/exchange of messages/exchange of 'cosmic bullets' over those distances.
  • @andreys7729
    Another refutation of Dark Forest hypothesis I can think of is this: among many existing space civs, there should be some civs that would create some kind of automated "grave beacon", that would be activated in case the civ is dead. It would start broadcasting to the whole universe the "letter from the grave" message: "If you are reading this letter, it means I'm dead. I was a cool civ, and now I'm dead, thank you for nothing. It is one of you who shot me down, isn't it? Have fun with the heatdeath, jerks". Since we don't observe such grave beacons out there, it means that: 1) either Dark Forest is correct AND killings of civs are very rare, or 2) Dark Forest is incorrect, and Fermi Paradox must be explained in some other way.
  • @ThomasMeli81
    The dark forest "conclusion" seems astonishingly sensitive to the (unrealistic) assumptions of the model. Just like the prisoner's dilemma has at least a dozen more realistic variants where collaboration becomes aligned with individual payoffs (repeated interactions, trust and reputation, evolving systems, network effects of interacting with others), I imagine that with slight tweaks you would not a dark forest. Given the intensity of the consequences, it seems important to also explore those variants. I like that you explored the flaws in the reasoning. The misapplication of models to reality seems to underlie a lot of public distrust in science, so I hope we all get better at thinking about these things.
  • @pacotaco1246
    lmao i applaud your ability to work Alice and Bob into the Dark Forest Hypothesis, two of my favorite recurring characters in Physics
  • @paulo6069
    MAD still applies, e.g. retaliation using a fleet of hidden Von Neumann probes similar to nuclear submarines today. Furthermore, any attacker would have to contend with civilizations unknown to them collaborating to destroy them in retaliation, so the "infinite cost" scenario is still in play should one attack another. EDIT: I just thought of an example of the latter. If any of you played Spore, you probably remember that using the planet buster (a weapon that destroys an entire planet) causes all civilizations nearby to hate you and likely to attack you on sight, including those that used to be allied with you.
  • @grandlotus1
    Refreshing to see that PBS Space Time can indulge in whimsy from time to time.
  • @HuxleysShaggyDog
    The premise "destroy easily" while also omitting an alliance is the problem. You throw out an RKKV or a death fleet (or whatever), and you don't succeed, you just made the survivors into the imperium of man. Even if the target planet is destroyed, if there are other colonies that are self sufficient and have enough knowledge to bootstrap, you've made eternal enemies. This also assumes nobody sees you do this, which is also pretty unlikely. Even with great delays, it's easy to imagine seeing someone setting up a Nicoll-Dyson beam or RKKVs, and easy to imagine alliances setting up, even if this is purely light speed communication and relativistic travel. What would motivate a space defense pact greater than a civilization blowing away its neighbors?
  • @PronatorTendon
    The radius inside which our incidental radio transmissions are detectable is far smaller than even purportedly scientifically literate people realize. When a signal goes below -194dB, it's indistinguishable from background noise. Our 100kw radio stations aren't reaching out 120 light years. They'll scarcely be detectable at Proxima Centauri
  • @davidtatro7457
    The Dark Forest hypothesis is always interesting to think about, but l think it's one of the weaker answers to the Fermi Paradox. The best answer so far (in my humble opinion) is that there is no paradox at all, because we've essentially only sampled one tiny drop of water from an entire ocean as it pertains to scanning space for alien signals. At this point, we have no basis for concluding that alien civilizations are either rare or quiet enough for this fact to require any explanation. All we can really say is that so far, nobody out there had been beaming extremely powerful and detectable signals directly at earth within the scant time and narrow frequency range we've been scanning.
  • @ICU1337
    Glad you finally touched on some of the ideas that shatter the dark forest hypo. Took you a minute to get there but you finally did. One thing that you didnt touch on that shatters this hypo is "what if we've already been visited by countless alien civilizations already", if we have and we're still here, doesnt that also shatter the idea that we're surrounded by a bunch of bloodthirsty alien civilizations that only exist to destroy each other🤔 The Dark Forest is an interesting hypothesis but in reality its something that best suited for those who are afraid of their own shadow and had our ancestors followed in their footsteps, we would still be a single cell life form swirling around in the primordial ooze.
  • @junkred9466
    When I see how different and unmerciful we can be towards one another within our own species, I’m not sure I want to see how it would turn out between two different species, from two different worlds