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5 Sci-Fi Aliens — And The Likelihood They Could Actually Exist

Special Biology Blog on BigThink on 5 Types of Science Fiction Aliens and the Likelihood that they Actually Exist:

Link through my website Search for Life in the Universe: [ https://www.searchforlifeintheuniverse.com/post/5-sci-fi-ali…ally-exist](https://www.searchforlifeintheuniverse.com/post/5-sci-fi-ali…ally-exist)


While all cellular life on Earth shares the same DNA-based chemistry, planets with different environments could produce alien organisms far more diverse. From insect-like swarms to intelligent machines, many classic sci-fi alien archetypes have at least some grounding in biology, astrobiology, or emerging technology. Ultimately, truly alien life may defy our expectations altogether, and recognizing it could require rethinking not just what aliens look like, but how we define life itself.

If alien signals have already reached Earth, why haven’t we seen them?

For decades, scientists have searched the skies for signs of extraterrestrial technology. A study from EPFL asks a sharp question: if alien signals have already reached Earth without us noticing, what should we realistically expect to detect today?

Since the first SETI experiment in 1960, astronomers have scanned the Milky Way for signs of advanced extraterrestrial civilizations. These searches have covered radio waves, optical flashes, and infrared heat signatures.

So far, they have found nothing confirmed. That silence is often explained by saying we have only searched a tiny part of the cosmic landscape. But what if signals did reach Earth and slipped past us?

Committee co-chaired by Prof. Dava Newman issues a new roadmap for human missions to Mars

On December 9, the National Academies of Sciences, Engineering, and Medicine (NASEM) released a landmark report, A Science Strategy for the Human Exploration of Mars, laying out a comprehensive case for future crewed Mars missions. The report, authored by the Committee on a Science Strategy for the Human Exploration of Mars that was co-chaired by Prof. Dava Newman, defines the highest-priority scientific objectives for humans on the Martian surface.

At the top of the list: searching for evidence of past or present life. “We’re searching for life on Mars,” said Newman in an interview with Ars Technica. “The answer to the question ‘are we alone?’ is always going to be ‘maybe,’ unless it becomes yes.”

The report identifies 11 top science goals for initial human missions, including biosignature/habitability experiments and water and CO₂ cycle studies, geology mapping, radiation monitoring, dust-storm research, and assessments of how Martian conditions affect humans and ecosystems.

Alien Mathematics

Aliens will make use of paraconsistent logic.


Is math truly universal—or just human? Explore how alien minds might think, count, and reason in ways we don’t recognize as mathematics at all.

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Watch my exclusive video The Future of Interstellar Communication: https://nebula.tv/videos/isaacarthur–… out Joe Scott’s Oldest & Newest: https://nebula.tv/videos/joescott-old… 🚀 Join this channel to get access to perks: / @isaacarthursfia 🛒 SFIA Merchandise: https://isaac-arthur-shop.fourthwall… 🌐 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 Community: / isaacarthur 🐦 Follow on Twitter / X: / isaac_a_arthur 💬 SFIA Discord Server: / discord Credits: Alien Mathematics Written, Produced & Narrated by: Isaac Arthur Select imagery/video supplied by Getty Images Music by Epidemic Sound: http://nebula.tv/epidemic & Stellardrone Chapters 0:00 Intro 2:02 Why We Expect Mathematics to Be Universal 6:32 Math Is Not the Same Even for Humans 10:47 How Alien Biology Could Reshape Their Mathematics 16:44 Alien Logic: When the Rules Themselves Don’t Match 20:37 Oldest & Newest 21:41 Can We Ever Bridge the Mathematical Gap?
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Why Earth-like worlds might be rare

Dr. Craig Walton: “This makes searching for life on other planets a lot more specific. We should look for solar systems with stars that resemble our own Sun.”


How common are Earth-like worlds beyond our solar system? This is what a recent study published in Nature Astronomy hopes to address as an international team of scientists unveiled new evidence that Earth-like worlds might be rarer than previously thought. This study has the potential to help scientists better understand the formation and evolution of Earth-like worlds and what this could mean for finding life beyond Earth.

For the study, the researchers used a series of computer models to simulate the formation of the interiors of potential Earth-like worlds, specifically focusing on planetary interior formation. This is because the researchers note how nitrogen and phosphorus are essential for the formation of habitable worlds, and the planetary mantle, the layer just beneath the planetary crust, is where they are formed and exist.

In the end, the researchers found that the right amount of oxygen needs to be present within the mantle for nitrogen and phosphorus to form. They note while Earth has these conditions, worlds with less oxygen in their mantle could limit the ability of nitrogen and phosphorus to form, resulting in non-habitable worlds.

Why only a small number of planets are suitable for life

For life to develop on a planet, certain chemical elements are needed in sufficient quantities. Phosphorus and nitrogen are essential. Phosphorus is vital for the formation of DNA and RNA, which store and transmit genetic information, and for the energy balance of cells. Nitrogen is an essential component of proteins, which are needed for the formation, structure, and function of cells. Without these two elements, no life can develop out of lifeless matter.

A study led by Craig Walton, postdoc at the Center for Origin and Prevalence of Life at ETH Zurich, and ETH professor Maria Schönbächler has now shown that there must be sufficient phosphorus and nitrogen present when a planet’s core is formed. The study is published in Nature Astronomy.

“During the formation of a planet’s core, there needs to be exactly the right amount of oxygen present so that phosphorus and nitrogen can remain on the surface of the planet,” explains Walton, lead author of the study. This was exactly the case with Earth around 4.6 billion years ago—a stroke of chemical good fortune in the universe. This finding may affect how scientists search for life elsewhere in the universe.

Why the Multiverse Is Real | Leonard Susskind

The multiverse is often dismissed as speculation — a science-fiction idea with no place in serious physics. But for many theoretical physicists, the multiverse is not a fantasy. It is a conclusion.

In this video, we explore why the multiverse may be real.

This is not an argument based on imagination or popularity. It is based on what happens when modern physics is taken seriously. Well-tested ideas like cosmic inflation, quantum mechanics, and high-energy theory naturally lead to a picture in which our universe is not unique.

Drawing on ideas associated with Leonard Susskind, this documentary explains how the multiverse emerges as a consequence, not as an assumption. In inflationary models, different regions of space stop inflating at different times, producing universes with different properties. In theories with many possible vacuum states, the laws of physics themselves can vary from one region to another.

This framework helps explain one of the deepest puzzles in physics: fine-tuning. The constants of nature appear precisely adjusted for the existence of complex structures and life. In a single-universe picture, this looks mysterious. In a multiverse, it becomes a selection effect — we observe this universe because only certain universes can be observed at all.

The multiverse raises uncomfortable questions. It challenges prediction, explanation, and even the traditional goals of science. But discomfort is not a reason to reject a theory. If the multiverse is real, physics must adapt.

JWST uncovers rich organic chemistry in a nearby ultra-luminous infrared galaxy

A study led by the Center for Astrobiology (CAB), CSIC-INTA, using modeling techniques developed at the University of Oxford, has uncovered an unprecedented richness of small organic molecules in the deeply obscured nucleus of a nearby galaxy, thanks to observations made with the James Webb Space Telescope (JWST).

The work, published in Nature Astronomy, provides new insights into how complex organic molecules and carbon are processed in some of the most extreme environments in the universe.

The study focuses on IRAS 07251–0248, an ultra-luminous infrared galaxy whose nucleus is hidden behind vast amounts of gas and dust. This material absorbs most of the radiation emitted by the central supermassive black hole, making it extremely difficult to study with conventional telescopes.

20 Beings That Existed Before The Universe

What if the universe wasn’t the beginning? Long before the Big Bang, before the first stars ignited, and before time even had a direction, there were entities already lurking in the void.

Tonight, we’re diving into 20 beings that existed before the universe itself. From cosmic architects who engineered life in the stars to \.

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