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)

The Big Bang is the reigning explanation for our universe’s origin—but what if it’s wrong? This episode dives into cosmic controversies and the theories that challenge everything we thought we knew.



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Credits:

What If the Big Bang Never Happened?

Episode 730.1; July 6, 2025

Written, Produced & Narrated by: Isaac Arthur

Select imagery/video supplied by Getty Images

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





What If the Big Bang Never Happened?

This episode explores how spaceports will evolve in design, technology, and purpose—shifting from fuel-thirsty towers to seamless transport hubs for Earth, Moon, Mars, and beyond.
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Credits:
Spaceport Innovations - Designing the Next Generation of Launch Sites
July 10, 2025; Episode 731
Written, Produced & Narrated by: Isaac Arthur
Graphics:
Anthrofuturism
Atlantis Project
Jarred Eagley
Katie Byrne
Fishy Tree
Phil Swan
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Stellardrone, "Red Giant", "Billions and Billions"

Spaceport Innovations: Designing the Next Generation of Launch Sites (Narration Only)

Forget tentacles—what matters is the mind. We explore how alien behavior might emerge from evolution, culture, and technology, and why our biggest first contact risk may be misunderstanding.

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Credits:
How Would Aliens Behave?
July 13, 2025; Episode 732
Written, Produced & Narrated by: Isaac Arthur
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Stellardrone, "Red Giant"
Chapters
0:00 Intro - Alien Expectations vs. Reality
4:04 The Evolutionary Roots of  Alien Behavior
8:19 From Common Ground to Alien Paths: Divergent Behaviors
13:19 First Contact: Communication & Misunderstanding
20:11 Alien Morality: Do They Even Have Ethics?
26:04 Alien Minds, Human Limits: The Final Reflection

How Would Aliens Behave? (Narration Only)

Transhumanism promises a better humanity—or perhaps something no longer human at all. Join us as we explore the moral dilemmas and future paths of human augmentation.

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Credits:
How Would Aliens Behave?
July 13, 2025; Episode 732
Written, Produced & Narrated by: Isaac Arthur
Editor: Donagh Broderick
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Stellardrone, "Red Giant", "Billions and Billions"
Taras Harkavyi, "Alpha and..."

The Ethics of Transhumanism (Narration Only)

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:
Before the Big Bang - What Came Before Time?
Episode 738; July 20, 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 Asking the Impossible
2:08 The Limits of Time and Spacetime
7:45 Beyond the Big Bang: Alternate Beginnings
14:38 Other Realities: Higher Dimensions and Shadow Universes
18:28 Emergent Time
22:38 Bubble Collisions and Multiverse Scars
24:44 Conclusion: What Came Before Time?

Before the Big Bang - What Came Before Time?

Before the Big Bang - What Came Before Time? (Narration Only)

From metal scrolls buried under alien skies to frozen vaults holding minds or monarchs for millennia, we examine how advanced civilizations might safeguard their legacy against the slow grinding of eternity.

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Credits:
Vaults of Eternity - Planetary Archives & Stasis Fields - Extended Edition
Episode 741; July 27, 2025
Written, Narrated & Produced by: Isaac Arthur
Graphics:
Jeremy Jozwik
Sergio Botero
Music Courtesy of Epidemic Sound Epidemic Sound http://epidemicsound.com/creator

Vaults of Eternity - Planetary Archives & Stasis (Narration Only)

Aliens don’t always attack with lasers—sometimes, the smartest invasions begin with a gift, a whisper, or a smile. Join us as we count down ten invasion strategies that actually make sense.

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Credits:
The 10 Best Alien Invasion Strategies
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
1:20 10. The Infiltration Gambit: Invasion Without a War
3:58 9. False Prophets – The Alien Messiah Strategy
5:55 8. Weaponized Belief – Memes, Myths, and Messiahs
7:53 7. The Hybrid Convert Strategy
8:59 6. Shock and Awe: The Killing Star Approach
12:39 5. Divide and Conquer: Turning Humanity Into Its Own Worst Enemy
14:10 4. Trojan Tech: When the Upgrade Is the Invasion
17:40 3. Overwhelming Force and Organization
18:52 2. Preemptive Invasion & Interdiction for Conformity – The Galactic Empire Problem
20:32 Beyond Scorched Earth

The 10 Best Alien Invasion Strategies (Narration Only)

Explore the entire life story of the cosmos, from quantum flickers at the Big Bang to the distant eras of black holes and dark energy, and discover what kinds of civilizations might endure across these unimaginable spans of time.

Watch my exclusive video Mass Drivers on the Moon: https://nebula.tv/videos/isaacarthur-mass-drivers-on-the-moon-enabling-a-lunar-economy
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Credits:
Spaceport Innovations - Designing the Next Generation of Launch Sites
July 31, 2025; Episode 744
Written, Produced & Narrated by: Isaac Arthur
Epochs of the Universe - The Cosmic Clock & Civilization (July 31, 2025)
Recorded: June 2025
Written by: Isaac Arthur
Editor: Lukas Konecny
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator

Epochs of the Universe - The Cosmic Clock & Civilization (Narration Only)

Imagine engineering projects so vast they mold galaxies into new shapes. We’ll explore the staggering feats of Kardashev-3 and beyond civilizations, crafting CARD galaxies, Birch Planets, and even rearranging superclusters.

Watch my exclusive video Dark Biospheres: https://nebula.tv/videos/isaacarthur-dark-biospheres-life-on-worlds-without-sunlight
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Credits:
Spaceport Innovations - Designing the Next Generation of Launch Sites
August 3, 2025; Episode 746
Written, Produced & Narrated by: Isaac Arthur
Galaxy-Scale Megastructures & Kardashev-3 Civilizations
Written by: Isaac Arthur
Editor: Darius Said 
Graphics: Jeremy Jozwik, Ken York, Sergio Botero, Steve Bowers
Select imagery/video supplied by Getty Images 
Music Courtesy of Epidemic Sound http://epidemicsound.com/creator
Stellardrone, "Endeavour", "Red Giant", &"Billions and Billions"

Epochs of the Universe - The Cosmic Clock & Civilization (Narration Only)

Isaac Arthur

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