Matter. What is reality? And if it’s so fundamental, why do we all experience it so differently? Join us for a marathon through the discoveries and paradoxes that suggest modern physics is pointing to a deeply uncomfortable truth: that our picture of the universe is far from complete, and what we think about reality may be completely wrong.
00:00 Reality Is Already Broken 00:57 Scientists Build a Window into the Fourth Dimension 23:16 The Physicist Who Says Reality Is Not What It Seems 1:28:45 The Black Hole Paradox That Keeps Physicists Awake at Night 1:50:40 Sean Carroll: The Many Worlds of Quantum Mechanics 2:46:40 What are the foundations of reality?
About New Scientist: New Scientist was founded in 1956 for “all those interested in scientific discovery and its social consequences”. Today our website, videos, newsletters, app, podcast and print magazine cover the world’s most important, exciting and entertaining science news as well as asking the big-picture questions about life, the universe, and what it means to be human.
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.
Watch my exclusive video Fishbowl Starships — Water As Shielding — 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 https://gift.nebula.tv/isaacarthur to give a year of Nebula to a friend for just $36. Visit our Website: http://www.isaacarthur.net 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: 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” Chapters 0:00 Intro 5:33 What is Terraforming? 8:27 Terraforming vs Para-Terraforming 11:54 Planets vs Megastructures 14:05 Terraforming vs Bioforming 17:14 The Inevitable Hybrid Approach 20:59 Ethics & Debate: Preservation vs. Transformation 22:42 Terraforming as a Civilization-Scale Endeavor 23:46 Terraforming Technologies & Techniques 24:42 Artificial Gravity Solutions 27:58 Atmospheric Manipulation 31:25 Bioforming & Genetic Engineering 34:06 Comet & Asteroid Bombardment 39:43 Domes & Worldhouses 43:24 Geoengineering & Climate Control 47:05 Hydrospheric Engineering 49:58 Magnetosphere Generation 53:35 Fishbowl Starships 55:02 Mass & Orbital Adjustments 1:00:17 Mega-Mirrors & Solar Shades 1:04:30 Oxygenation & Soil Processing 1:07:39 Planetary Shells & Artificial Crusts 1:10:37 Terraforming Nanotechnology 1:14:04 Tidal & Seismic Stabilization 1:18:45 From Theory to Practice: Adapting Terraforming to Specific Worlds 1:20:27 Extreme Radiation Levels 1:23:57 Frequent Asteroid & Meteor Impacts 1:27:41 High Gravity 1:30:29 Highly Eccentric Orbits 1:34:46 Hostile Native Life 1:38:25 Intense Volcanism 1:40:55 Long or Erratic Day/Night Cycles 1:51:09 Low Light Levels 1:52:57 No Air 1:54:25 No Magnetosphere 1:56:17 No Seasons 1:58:13 No Water 2:00:48 Short or Long Years & Seasons 2:02:05 Tidally Locked 2:03:32 Tidally Wracked 2:04:36 Too Cold 2:05:36 Too Hot 2:06:21 Too Much Air 2:07:05 Too Much Ocean 2:08:44 Too Much Solar Wind 2:11:13 Toxic or Corrosive Atmosphere or Surface 2:14:09 Unstable Tectonics 2:15:10 Wrong Air Composition 2:16:21 Final Thoughts. 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. Support us on Patreon: / isaacarthur. Support us on Subscribestar: https://www.subscribestar.com/isaac-a… Facebook Group: / 1583992725237264 Reddit: / isaacarthur. Twitter: / isaac_a_arthur on Twitter and RT our future content. SFIA Discord Server: / discord. 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, \
Space. Time. Matter. What is reality? And if it’s so fundamental, why do we all experience it so differently? Join us for a marathon through the discoveries and paradoxes that suggest modern physics is pointing to a deeply uncomfortable truth: that our picture of the universe is far from complete, and what we think about reality may be completely wrong.
00:00 Reality Is Already Broken 00:57 Scientists Build a Window into the Fourth Dimension 23:16 The Physicist Who Says Reality Is Not What It Seems 1:28:45 The Black Hole Paradox That Keeps Physicists Awake at Night 1:50:40 Sean Carroll: The Many Worlds of Quantum Mechanics 2:46:40 What are the foundations of reality?
Excellent review in which Solé et al. explore how physical/mathematical constraints may determine what subset of biological systems could theoretically evolve in the universe. Lots of fascinating ideas applying concepts like Turing machines, cellular automata, McCulloch-Pitts networks, energy minimization, and phase transitions to multiscale biological and evolutionary phenomena!
I found the description of how parasites almost inevitably emerge and drive increased biodiversity in computational models of evolution particularly fascinating. Interestingly, I recall this idea was featured in the Hyperion Cantos novels during an explanation of the history of artificial intelligence in their fictional universe!
Abstract. It has been argued that the historical nature of evolution makes it a highly path-dependent process. Under this view, the outcome of evolutionary dynamics could have resulted in organisms with different forms and functions. At the same time, there is ample evidence that convergence and constraints strongly limit the domain of the potential design principles that evolution can achieve. Are these limitations relevant in shaping the fabric of the possible? Here, we argue that fundamental constraints are associated with the logic of living matter. We illustrate this idea by considering the thermodynamic properties of living systems, the linear nature of molecular information, the cellular nature of the building blocks of life, multicellularity and development, the threshold nature of computations in cognitive systems and the discrete nature of the architecture of ecosystems. In all these examples, we present available evidence and suggest potential avenues towards a well-defined theoretical formulation.
Southwest Research Institute was part of an international team that demonstrated how complex organic molecules (COMs), key chemical precursors to life, could have been incorporated into Jupiter’s Galilean moons during their formation. The team’s findings have resulted in complementary studies published in The Planetary Science Journal and Monthly Notices of the Royal Astronomical Society, offering new insights into the potential for life in the Jovian system.
How complex organics can form Carbon-rich compounds containing oxygen, nitrogen and other elements are necessary for living matter to form. Laboratory experiments have shown that COMs can form when icy grains containing methanol or mixtures of carbondioxide and ammonia are exposed to either ultraviolet radiation or moderate heating under conditions found in protoplanetary disks. These disks of gas and dust surround newly formed stars that eventually form planets.
“By combining disk evolution with particle transport models, we could precisely quantify the radiation and thermal conditions the icy grains experienced,” said Dr. Olivier Mousis of SwRI’s solar system science and exploration division, who is lead author of one of the two studies. “Then we directly compared our simulations with other laboratory experiments that produce COMs under realistic astrophysical conditions. The results showed that COM formation is possible in both the protosolar nebula environment and Jupiter’s circumplanetary disk.”
Astronomers have found that both the core of our Milky Way and the earliest proto-galaxies in the universe share a surprising trait: They are unusually calm and quiet in terms of harsh radiation. This tranquility is not just a cosmic curiosity; it may be essential for forming complex molecules that provide the ingredients of life.
A new study published in The Astrophysical Journal Letters highlights how the Milky Way’s center and mysterious early proto-galaxies known as “little red dots” (LRDs) harbor massive black holes within peaceful, dust-and gas-rich environments. These conditions create natural laboratories for prebiotic chemistry, suggesting that the universe may have supported life’s chemical precursors far earlier than previously imagined.
The work was led by Professor Remo Ruffini and Professor Yu Wang from the International Center for Relativistic Astrophysics Network (ICRANet) and the Italian National Institute for Astrophysics (INAF).
Dr. Vishal Gajjar: “If a signal gets broadened by its own star’s environment, it can slip below our detection thresholds, even if it’s there, potentially helping explain some of the radio silence we’ve seen in technosignature searches.”
What steps can be taken to identify why we haven’t received radio signals from an extraterrestrial intelligence, also called technosignatures? This is what a recent study published in The Astrophysical Journal hopes to address as a team of scientists investigated potential explanations regarding why humanity continues hearing silence from technosignatures. This study has the potential to help scientists and the public better understand the shortcomings and enhancements that can be made in the search for intelligent life beyond Earth.
For the study, the researchers used a series of computer models to simulate how radio signals leaving extrasolar star systems could be influenced by a myriad of factors, specifically space weather coming from the host star. This study comes as SETI and other researchers worldwide continue to come up empty regarding identifying technosignatures. The goal of the study was to ascertain potential reasons while putting constraints on both how and where to search for technosignatures.
In the end, the researchers ascertained that space weather plays a role in altering the outgoing radio signals by dispersing them, as opposed to the radio signals maintaining a fixed beam. The team ascertained that M-dwarf stars, which constitute approximately 75 percent of the stars in the Milky Way Galaxy while being smaller and cooler than our Sun, are prime targets for searching for technosignatures. This is due to their space weather, which is far more active than stars like our Sun, dispersing the radio signals.
In 2017, headlines around the world declared the simulation hypothesis dead. Physicists had debunked it, the articles said. We could all move on. There was one problem. The paper they cited never mentioned the simulation hypothesis. The debunking was invented by journalists who never read the research. And in the years since, the actual physics has gotten significantly worse.
This documentary follows that physics all the way down.
We begin with what really happened in 2017 — the Ringel-Kovrizhin paper, what it actually proved, and Scott Aaronson’s correction that nobody shared. Then we examine Nick Bostrom’s original 2003 trilemma, the real math behind it, and why two decades of attacks from Sean Carroll, Lisa Randall, and Sabine Hossenfelder have failed to break it. Every critique concedes something. Every attempted kill shot narrows the escape routes.
From there, we trace the physics of information through three remarkable lives. Konrad Zuse, who built the first programmable computer in his parents’ living room during the bombing of Berlin, then proposed in 1967 that the universe itself is a computation — and was ignored. John Archibald Wheeler, who lost his brother in World War Two and spent the rest of his life asking whether reality is built from information, condensing it into three words that changed physics: \.
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: / 1583992725237264 Reddit: / isaacarthur. Twitter: / isaac_a_arthur on Twitter and RT our future content. SFIA Discord Server: / discord. Credits: Cosmic Megafauna — Could Giant Alien Life Forms Exist? Episode 727; June 26, 2025 Written, Produced & Narrated by: Isaac Arthur. Select imagery/video supplied by Getty Images. Music Courtesy of Epidemic Sound http://epidemicsound.com/creator. Stellardrone, \
