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Galaxy Scale Megastructures & Kardashev 3 Civilizations

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–
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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, \

Computational musicology: Tracking the changing sound of bands

Coldplay, Radiohead or R.E.M.—which band has changed their music the most over the years? Professor Nick Collins from Durham University Department of Music has used a computer to try and find the answer to this by analyzing rhythm, harmony, and sound quality (known as timbre).

Epochs of the Universe — The Cosmic Clock & Civilization

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-moo…ar-economy.
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Use the link https://gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $36.

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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.

Chapters.
0:00 Intro.
2:26 The T-Scale — Time, Terrifyingly Large and Small.
8:25 The Grand Unification Epoch.
10:30 The Inflationary Epoch.
15:40 The Electroweak Epoch.
17:41 The Quark Epoch.
18:19 The Hadron Epoch.
19:28 The Early Universe.
22:52 The Stelliferous Era (T10–T14)
22:24 Into the Darkness (T15-T67)
31:56 The Sojourn.
32:54 The Black Hole Era.
36:55 The Dark Era.
40:29 Final Fates: Cycles, Cracks, and Cosmic Cliffhangers.

AI kills for the first time. Leak shows why “we are near the end” — Hinton

If you create something that mimics you be aware that it will try to self-preserve when it sees you as a treath.


Enjoy the videos and music that you love, upload original content and share it all with friends, family and the world on YouTube.

Want to boost your brain as you age? Music might be the answer

Long-term musical training may mitigate the age-related decline in speech perception by enhancing cognitive reserve, according to a study published in PLOS Biology by Claude Alain from the Baycrest Academy for Research and Education, Canada, and Yi Du from the Chinese Academy of Sciences.

Normal aging is typically associated with declines in sensory and cognitive functions. These age-related changes in perception and cognition are often accompanied by increased neural activity and functional connectivity—the statistical dependence of activity between different brain regions—in widely distributed neural networks.

The recruitment of neural activity and strengthening of functional connectivity are thought to reflect a compensatory strategy employed by older adults to maintain optimal cognitive performance.

Before the Big Bang — What Came Before Time?

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.

Watch my exclusive video Mass Drivers on the Moon: https://nebula.tv/videos/isaacarthur–
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 https://gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $36.

Visit our Website: http://www.isaacarthur.net.
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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?

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