In tomorrow’s world, cities may rise into the clouds, dive beneath oceans, or float among the stars—join us as we journey through these radical urban frontiers.

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Credits:
Cities of the Future 
Episode 498; May 8, 2025
Written, Produced & Narrated by: Isaac Arthur
 Edited by: Briana Brownell & Thomas Owens
Graphics: Bryan Versteeg, Ervin Oprea, Ken York YD Visual, Sergio Botero
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Chris Zabriskie, "Unfoldment, Revealment", "A New Day in a New Sector", "Wonder Cycle"
Taras Harkavyi, "Alpha and..."
Stellardrone, "Red Giant", "Billions and Billions"

498 V Cities of the Future May 8, 2025

The Fermi Paradox asks why, in a vast and ancient universe, we see no signs of alien life. In this episode, we explore five explanations that make sense—and seven popular ones that, despite sounding good, fall flat under closer scrutiny.

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Credits:
5 Fermi Paradox Explanations I Love, 7 That Fall Flat
Episode 502 / 721; May 31, 2025
Written, Produced & Narrated by: Isaac Arthur
Graphics: Ken York YD Visual
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator

0:00 Intro
1:11 Space Is Too Big
4:46 Rare Earth
6:35 Aliens Signals Just Can’t Be Heard
10:09 Humans Are Boring
11:36 Dark Forest Theory
14:14 Interdiction Bubble Civilizations
16:49 Hermit Hypothesis
19:18 Aestivation Hypothesis and Extragalactic Migration
21:10 Transcendance, Ascension, and Extra-Universe Migration
22:33 Infinite Miniaturization
23:33 Berserkers & Zombie AI
24:53 Aliens Common But Unrecognizable 
26:08 Simulation Hypothesis


5 Fermi Paradox Explanations I Love… and 7 That Fall Flat (Narration Only)

Are we alone in the universe—or just early to the party? We’ll explore the math, models, and megastructures that might answer how many alien civilizations are out there, and why the night sky remains so quiet.

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Credits:

How Many Alien Civilizations Are There?

Episode 723; June 8, 2025 

Written, Produced & Narrated by: Isaac Arthur

Editor: Ludwig Luska

Graphics: Ken York YD Visual

Select imagery/video supplied by Getty Images

Music Courtesy of Epidemic Sound http://epidemicsound.com/creator

Phase Shift, "Forest Night"

 Chris Zabriskie, "Unfoldment, Revealment" & "A New Day in a New Sector" 

Koalips, "Kvazar"

 Stellardrone, "Red Giant" & "Billions and Billions"

How Many Alien Civilizations Are There? (Narration Only)

Could we sculpt dead planets into living worlds? From artificial crusts and orbital mirrors to taming tectonics and engineering biospheres, this is your definitive guide to turning alien rocks into second Earths.

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Credits:
Interstellar Travel: Can We Survive The Long Journey?
Episode 725; June 15, 2025
Written, Produced & Narrated by: Isaac Arthur
Graphics:
Jarred Eagley
Jeremy Jozwik
Ken York YD Visual
Mafic Studios
Sergio Botero
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Chris Zabriskie, "Unfoldment, Revealment", "A New Day in a New Sector", "Oxygen Garden", "Wonder Cycle"
Kai Engel, "Endless Story About Sun and Moon"
Taras Harkavyi, "Alpha and..."
Dark Future, "Staring Through" pt1
Miguel Johnson. "The Commanders", "Far From Home"
Lombus, "Hydrogen Sonata", "Cosmic Soup"
Aerium, "Deijocht"
Stellardrone, "Red Giant", "Solar Eclipse", "Billions and Billions"

The Terraforming Compendium - From Barren Rocks to Living Worlds (Narration Only)

In order to succeed in space, we must be able to produce as much as possible on-site, or ‘in situ’, but what are the most critical resources to harvest and how do we do it?

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Credits:
I.S.R.U. In-Situ Resource Utilization
Written, Narrated & Produced by: Isaac Arthur
Graphics:
Fishy Tree
Jeremy Jozwik
Ken York / YD Visual
Sergio Botero
Udo Schroeter
Music Courtesy of
Epidemic Sound Epidemic Sound http://epidemicsound.com/creator


ISRU: In-Situ Resource Utilization (Narration Only)

Explore the real economics of building and operating a space elevator—from ship-launched ribbons to megaton climbers—and how this infrastructure could change the world.

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Credits:
Space Elevator Economics: Building And Operating A Superhighway To Space 
Episode 726; June 19, 2025
Written, Produced & Narrated by: Isaac Arthur
Edited by:
Adrian Nixon
Ludwig Luska
Peter Swan
Graphics:
Anthrofuturism
Atlantis Project
Katie Byrne
Phil Swan
Sergio Botero
Udo Schroeter
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Chris Zabriskie, "Unfoldment, Revealment", "A New Day in a New Sector"
Aerium, "Deijocht"
Stellardrone, "Red Giant", "Billions and Billions"
Lombus, "Hydrogen Sonata", "Cosmic Soup"

Space Elevator Economics - Building And Operating A Superhighway To Space (Narration Only)

From quantum tunneling to cosmic inflation, we journey through the theories behind the Big Bang and beyond — and ask the big question: could another Big Bang be in our cosmic future?

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Credits:
Could We See a Second Big Bang?
Episode 724.1; June 10, 2025
Written, Produced & Narrated by: Isaac Arthur
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator


0:00 Intro
1:59 Why Did the Big Bang Happen?
3:01 Quantum Fluctuations
5:20 Inflation and False Vacuum Decay
7:56 Cyclic Models and the Ekpyrotic Universe
9:43 Big Bounce Cosmology 
12:35 Tunneling from Nothing 
14:04 Beginnings, Endings, and Echoes

Could We See a Second Big Bang?

In-situ resource utilization (ISRU) is the key to building lasting colonies in space—by turning local materials into shelter, fuel, and even food. Explore how humanity might thrive beyond Earth by living off the land on other worlds.

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Credits:
I.S.R.U. In-Situ Resource Utilization
Written, Narrated & Produced by: Isaac Arthur
Graphics:
Fishy Tree
Jeremy Jozwik
Ken York / YD Visual
Sergio Botero
Udo Schroeter
Music Courtesy of
Epidemic Sound Epidemic Sound http://epidemicsound.com/creator

Chapters:
0:00 Intro
3:20 Shelter
11:06 Extraction of Volatiles
13:45 Regolith Processing
16:55 Energy Production
18:19 Manufacturing and Construction
20:24 Agriculture
23:40 Propellant Production
26:25 Starlifting

ISRU: In-Situ Resource Utilization - From Regolith to Rocket Fuel

ISRU: In-Situ Resource Utilization - From Regolith to Rocket Fuel (Narration Only)

From Martians undone by germs to predators who insist on sporting duels, we explore the most ridiculous alien invasion tactics in fiction, and what they reveal about strategy, science, and human resilience.

Join us as we journey beyond the birth of the universe to unravel the mysteries of what might have preceded the Big Bang—and whether time itself had a beginning.
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Credits:
The 10 Worst Alien Invasion Strategies
Episode 733; July 1, 2025
Written, Produced & Narrated by: Isaac Arthur
Select imagery/video supplied by Getty Images 

Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
0:00 Intro
0:48 10. The “Park and Wait” Strategy
2:02 9. Invading a Planet That Can Kill You
3:46 8. Single Point of Failure: The Hive or Control Ship
5:22 7. Telegraphing Your Arrival
6:50 6. Overly Convoluted Takeovers
8:30 5. Broadcasting Your Weakness
9:55 4. Playing Fair & Ritual Combat
11:54 3. Overconfidence & Underestimating the Locals
13:07 2. Hive Minds That Collapse Instantly
15:03 1. Ignoring the Home Field Advantage
16:06 Outro

The 10 Worst Alien Invasion Strategies (Narration Only)

If everything is free, what’s still worth striving for? From replicators to reputation, we examine the surprising economics of a post-scarcity world.
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Credits:
The Economics of a Post-Scarcity Universe - What Happens When Everything Is Free?
Episode 730; July 3, 2025
Written, Produced & Narrated by: Isaac Arthur
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Chapters
0:00 Intro
2:02 What Post-Scarcity Means Economically
5:10 Incentives Without Scarcity
8:17 Distribution, Duty, and Designed Idleness
14:27 Ownership and Property in a Post-Scarcity Economy
20:03 The Star Trek Economy & the Myth of a Moneyless Society
22:58 Wealth, Inheritance & Intergenerational Power
27:57 Upward Mobility and Inequality
29:02 Economic Failure Modes in Post-Scarcity
30:35 Where Economics Still Matters
33:02 The Infinite Price of a Meaningful Life