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By popular request we’ve begun adding playlists of the show as Podcasts on Youtube Music, I’ll try to add a new one every 2–3 days till we have most of our inventory up there, but given today’s Episode is *Cities of the Future*, a collection of all of those seemed a good idea https://www.youtube.com/playlist?list=PLIIOUpOge0LuyCbYUhy-79RQKkOXonmx4 These are the (tentatively named) upcoming playlists/podcasts list I’ll be adding, in no particular order: Megastructures & Extreme Engineering The Fermi Paradox & Alien Civilizations Space Colonization & Habitats Post-Scarcity & Future Civilizations Transhumanism & Human Evolution Propulsion & Interstellar Travel Terraforming & Planetary Engineering Mind, Machines & Alien Intelligence Future Warfare & Defense Strange Worlds & Alien Life.

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While you won’t see a trace of this exoplanet or alien life, it’s easy to spot the red dwarf star that warms its surface.

You may never come face to face with your favorite rock star, but you can attend their concerts or listen to a music recording. Celestial bodies can be like that. Amateurs can’t see black holes, exoplanets, and accretion disks, but we can detect their presence by how they interact with their surroundings. At the very least we can picture them in our mind’s eye.

For example, a likely exoplanet orbits the 1st-magnitude star Pollux in the Gemini twins. It even has a name — Thestias. At public events, I point to Pollux and explain that a planet twice as massive as Jupiter orbits the red giant every 590 days. When it comes to novae, including the woefully-behind-schedule T Cor Bor, it’s fun to imagine the “single” star as a pair of tightly orbiting suns. One pilfers hydrogen from the other until enough material accumulates on the thief’s surface to detonate in a brilliant thermonuclear explosion. Voilà — a nova!

What if the galaxy isn’t empty—but locked in a silent Cold War between ancient alien empires? This episode explores the Dark Forest Theory, Interdiction Bubbles, and what it means if our galaxy is shaped by dormant, watchful civilizations playing a long game of survival and subtle dominance.

Watch my exclusive video Antimatter Propulsion: Harnessing the Power of Annihilation — https://nebula.tv/videos/isaacarthur–… Nebula using my link for 40% off an annual subscription: https://go.nebula.tv/isaacarthur Get a Lifetime Membership to Nebula for only $300: https://go.nebula.tv/lifetime?ref=isa… Use the link gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $30. Visit our Website: http://www.isaacarthur.net Join Nebula: https://go.nebula.tv/isaacarthur Support us on Patreon: / isaacarthur Support us on Subscribestar: https://www.subscribestar.com/isaac-a… Facebook Group: / 1,583,992,725,237,264 Reddit: / isaacarthur Twitter: / isaac_a_arthur on Twitter and RT our future content. SFIA Discord Server: / discord Credits: The Alien Cold War: Silent Competition Among Dormant Empires In A Dark Galaxy Episode 497; May 1, 2025 Written, Produced & Narrated by: Isaac Arthur Edited by: Donagh Broderick Graphics: Darth Biomech, Jeremy Jozwik, Ken York YD Visual, LegionTech Studios, Sergio Botero Select imagery/video supplied by Getty Images Music Courtesy of Epidemic Sound http://epidemicsound.com/creator Markus Junnikkala, “A Fleet Behind the Moon” Phase Shift, “Forest Night” Kai Engel, “Endless Story About Sun and Moon” Chris Zabriskie, “Unfoldment, Revealment”, “A New Day in a New Sector”, “Cylinder One” Taras Harkavyi, “Alpha and…” Stellardrone, “Red Giant”, “Billions and Billions“
Get Nebula using my link for 40% off an annual subscription: https://go.nebula.tv/isaacarthur.
Get a Lifetime Membership to Nebula for only $300: https://go.nebula.tv/lifetime?ref=isa
Use the link gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $30.
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Credits:
The Alien Cold War: Silent Competition Among Dormant Empires In A Dark Galaxy.
Episode 497; May 1, 2025
Written, Produced & Narrated by: Isaac Arthur.
Edited by: Donagh Broderick.
Graphics: Darth Biomech, Jeremy Jozwik, Ken York YD Visual, LegionTech Studios, Sergio Botero.
Select imagery/video supplied by Getty Images.
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator.
Markus Junnikkala, \

Love this short paper which reveals a significant insight about alien life with a simple ‘back-of-the-envelope’ calculation! — “We find that as long as the probability that a habitable zone planet develops a technological species is larger than ~10^-24, humanity is not the only time technological intelligence has evolved.” [In the observable universe]

Free preprint version: https://arxiv.org/abs/1510.

#aliens #astrobiology #life #universe


Abstract In this article, we address the cosmic frequency of technological species. Recent advances in exoplanet studies provide strong constraints on all astrophysical terms in the Drake equation. Using these and modifying the form and intent of the Drake equation, we set a firm lower bound on the probability that one or more technological species have evolved anywhere and at any time in the history of the observable Universe. We find that as long as the probability that a habitable zone planet develops a technological species is larger than ∼10−24, humanity is not the only time technological intelligence has evolved. This constraint has important scientific and philosophical consequences. Key Words: Life—Intelligence—Extraterrestrial life. Astrobiology 2016359–362.

This week, researchers uncovered the negative pressure mechanisms plants use to communicate stress. Linguists found that the melody of spoken language in English functions as its own, distinct language. And there was also depressing news! Like the Trump administration slashing NASA’s budget, which could scrap the James Webb Space Telescope right at the beginning of its operational life (they’re also pushing to scrap the completed Nancy Grace Roman Space Telescope before its launch).

Additionally, researchers found that the video game Dark Souls has positive psychological effects on players; a physicist made a new contribution to the theory that the universe is a computational process; and scientists in Spain mapped the brain connectivity patterns of psychosis patients:

How likely is it that we live in a simulation? Are virtual worlds real?

In this first episode of the 2nd Series we delve into the fascinating topic of virtual reality simulations and the extraordinary possibility that our universe is itself a simulation. For thousands of years some mystical traditions have maintained that the physical world and our separated ‘selves’ are an illusion, and now, only with the development of our own computer simulations and virtual worlds have scientists and philosophers begun to assess the statistical probabilities that our shared reality could in fact be some kind of representation rather than a physical place.
As we become more open to these possibilities, other difficult questions start to come into focus. How can we create a common language to talk about matter and energy, that bridges the simulated and simulating worlds. Who could have created such a simulation? Could it be an artificial intelligence rather than a biological or conscious being? Do we have ethical obligations to the virtual beings we interact with in our virtual worlds and to what extent are those beings and worlds ‘real’? The list is long and mind bending.

Fortunately, to untangle our thoughts on this, we have one of the best known philosophers of all things mind bending in the world, Dr. David Chalmers; who has just released a book ‘Reality+: virtual worlds and the problems of philosophy’ about this very topic. Dr. Chalmers is an Australian philosopher and cognitive scientist specialising in the areas of philosophy of mind and philosophy of language. He is a Professor of Philosophy and Neuroscience at New York University, as well as co-director of NYU’s Center for Mind, Brain and Consciousness. He’s the founder of the ‘Towards a Science of Consciousness Conference’ at which he coined the term in 1994 The Hard Problem of Consciousness, kicking off a renaissance in consciousness studies, which has been increasing in popularity and research output ever since.

Donate here: https://www.chasingconsciousness.net/episodes.

What we discuss in this episode:
00:00 Short Intro.
06:00 Synesthesia.
08:27 The science of knowing the nature of reality.
11:02 The Simulation Hypothesis explained.
15:25 The statistical probability evaluation.
18:00 Knowing for sure is beyond the reaches of science.
19:00 You’d only have to render the part you’re interacting with.
20:00 Clues from physics.
22:00 John Wheeler — ‘It from bit’
23:32 Eugene Wigner: measurement as a conscious observation.
27:00 Information theory as a useful but risky hold-all language tool.
34:30 Virtual realities are real and virtual interactions are meaningful.
37:00 Ethical approaches to Non-player Characters (NPC’s) and their rights.
38:45 Will advanced AI be conscious?
42:45 Is god a hacker in the universe up? Simulation Theology.
44:30 Simulation theory meets the argument for the existence of God from design.
51:00 The Hard problem of consciousness applies to AI too.
55:00 Testing AI’s consciousness with the Turing test.
59:30 Ethical value applied to immoral actions in virtual worlds.

References: