12 ms·
Can self-replicating species flourish in the interior of a star? (2020) [pdf]
- drjasonharrison 4y agoAFAIK, this isn't an "April's Fools" paper. https://www.sciencealert.com/physicists-argue-that-life-based-on-cosmic-strings-may-be-possible-inside-stars https://www.sciencealert.com/physicists-argue-that-life-base...
- ndsipa_pomu 4y agoOn seeing the title, I was wondering if this was connected to The Algebraist by Iain M Banks. Edit: I've misremembered the story and confused stars with gas giants
- JoBrad 4y agoReminds me of a less-snarky version of Ryland Grace’s paper (from Project Hail Mary). The absolute extremes a living organism would need to be able to survive are insane.
- steppi 4y agoThere’s a 1964 story, The Truth, by Stanislaw Lem on this matter which is worth a read [0] [0] https://thereader.mitpress.mit.edu/the-truth-by-stanislaw-lem/ https://thereader.mitpress.mit.edu/the-truth-by-stanislaw-le...
- bmitc 4y agoDragon's Egg by Robert L. Forward is a novel that has a species living on the surface of a neutron star.
- viksit 4y agothis was amazing thank you! do you have a list of books you read or recommend (goodreads) to peek at?
- steppi 4y agoNot at the moment, but it’s a good suggestion. I should start putting something together like that. Feel free to email me though if you want to talk about books. You can find my email at the link in my profile.
- johngossman 4y agoThank you! Did not realize there was a Lem book I had not read.
- Sosh101 4y agoStar Maker, by Olaf Stapledon also touches on this.
- neatze 4y agoRelevant short sci-fi story how such alien lifeform would view us; https://www.mit.edu/people/dpolicar/writing/prose/text/thinkingMeat.html https://www.mit.edu/people/dpolicar/writing/prose/text/think...
- jonplackett 4y agoI enjoyed this very much, thank you Here’s a snippet for anyone interested "So who made the machines? That's who we want to contact." "They made the machines. That's what I'm trying to tell you. Meat made the machines." "That's ridiculous. How can meat make a machine? You're asking me to believe in sentient meat."
- jerf 4y agoWhile this paper acknowledges at the beginning the need to pump entropy out of a system faster than the local system is injecting it (criterion three, but that is my own summary, and a bit different than they phrased it), and they claim they cover it, I don't actually see how they cover it. The only thing they discuss is the gradient between the inner star and outer star, which does indeed involve an energy flow, but the relevant question is whether you can get a gradient between the "inside" and the "outside" of the organism and pump enough entropy out of it to make up for what is being generated inside. I am deeply skeptical of any such claim for the inside of a star because of the sheer amount of entropy constantly being jammed in by the environment. A star entity would be made of relatively normal matter (compared to some other things), even mediated through magnetic fields, and would be working on not entirely dissimilar time constraints from us, so it is difficult to see how that could work. (Contrast Robert Forward's story about critters living on old, relatively quiescent neutron stars: https://en.wikipedia.org/wiki/Dragon%27s_Egg https://en.wikipedia.org/wiki/Dragon%27s_Egg While if I had to bet, I'd bet reality still makes that impossible, at least the Cheela creatures built of degenerate matter would be working with reactions that themselves run much more quickly than our normal matter reactions do, so one can imagine that even though their environment is pumping more entropy in than our environment does per second, perhaps something could run more quickly and pump it out again at rates conventional matter could not. A star creature is in an environment that could run at perhaps modest, single-digit multiples "faster" than us, but is getting enormous multiples more entropy pumped in. I don't see the ratio working out favorably.)
- leejoramo 4y agoDragon’s Egg is my favorite hard SF novel. I remember attending a session with Robert Forward at an early 1980s World Science Fiction Convention and was amazed at how much detail science and math Forward put into his books.
- idiotsecant 4y agoAgreed, great book. Anyone who enjoys thinking about the extremes of possible life might also enjoy Blindsight by Peter Watts. It blew my mind about the nature of thought and consciousness in the same way dragon's egg blew my mind about the nature of time and consciousness.
- vodou 4y agoBetteridge says no. https://en.wikipedia.org/wiki/Betteridge%27s_law_of_headlines https://en.wikipedia.org/wiki/Betteridge%27s_law_of_headline...
- bobkazamakis 4y agoHow about you let us know when it says yes.
- Geee 4y agoCould you engineer a system, with a huge computer and fusion reactor to look like a star? Consider that all life would be digital at this point. If we take energy production and computation to the limit with huge scale, it might start to resemble a star. It would also be a perfect hiding place and defensive structure against aggressors. Rather than trying to eliminate your heat signature, you max it and hide in plain sight.
- FredPret 4y agoThat's a great idea for a scifi novel right there. I wonder if you could steer the star around by shining more of the radiation out of one end, or focus it all into a beam of death
- Geee 4y agoIn addition to Kardashev scale, there should be a scale for how much power can a civilization project on an enemy at once. More advanced civilization should be able to project more power on similar scale as Kardashev. I.e. being able to project one star's power on an enemy would be a type 2 civilization.
- olex 4y agoThere's a great concept that I found out about reading Schlock Mercenary (a sci-fi webcomic), about using a gas giant as an interstellar spaceship [1]. It probably originates elsewhere, but it was nicely explained there. You build a "candle" (huge tube) that is inserted into the gas giant on one side, then ignite the gases inside it (iirc the comic uses fusion reactors on both ends, and an intake in the center of the candle). Both ends of the candle are open, "inner" end counteracts the gas giant's gravity to keep the candle from sinking into the core, the other end produces thrust. You put your payload on moons that orbit around the gas giant, and steer by moving the candle. The "thrust end" of the candle also doubles as a light and heat source for the moons, replacing the sun while in interstellar space. There are... some risks involved into the whole operation. [1]: https://www.schlockmercenary.com/2003-08-03 https://www.schlockmercenary.com/2003-08-03
- idiotsecant 4y ago
- RajT88 4y agoThe paper hedges its bets on a rather lower bar for the definition of life. By which definition, prions would likely be considered to be alive. But I think the consensus is that prions aren't alive, and are just self-replicating proteins.
- raydiatian 4y ago> Life can be thought out as a dynamical hy- percycle (DNA encodes proteins, proteins help DNA to self- replicate, DNA encodes proteins, etc.) that can survive indefi- nitely as long as free energy is available for it, and as long as self-replication goes faster than the destruction of information carriers. Somebody posted something on here awhile back, definitely last 2 years, that suggested a really novel & fun to think about view on “life”, stating that life is a manifold for information through spacetime. DNA must replicate in order to prevent its dissolution into entropy, and life therefore exists because nature threw together the right random shape for the building blocks of self-preserving space-time informational manifolds. I’m doubtlessly paraphrasing and summarizing poorly, but my inner hippie was going “whooaaaa mannnnn far out!!”
- helf 4y agoNo one has mentioned Andy Weir’s “Hail Mary” yet?? :) fun book with “astrophages”.
- mcdonje 4y agoIIRC, they didn't live inside stars.
- helf 4y agoTrue. I think it’s on the surface. BUT THATS JUST WHAT WE KNOW ABOUT in that universe XD jazz hands
- marcusverus 4y agoFun is the perfect word for it. Hail Mary was the first time I ever read a newly released book and immediately thought "that's a classic".
- raydiatian 4y ago…sssssssspoiler alert
- skykooler 4y agoFor the first chapter, sure.
- raydiatian 4y agoReflexive contrarianism detected
- helf 4y agoI actually thought about that after I had typed it and left it for awhile. WOOPS
- raydiatian 4y agoYeah HN isn’t a place where you can redact spoilers, something I realized after I had typed it and left it for awhile. WOOPS
- optimalsolver 4y agoThis was the idea behind Frederik Pohl's novel The World At The End Of Time: https://en.wikipedia.org/wiki/The_World_at_the_End_of_Time https://en.wikipedia.org/wiki/The_World_at_the_End_of_Time
- irrational 4y agoAnd Dragon's Egg https://en.wikipedia.org/wiki/Dragon%27s_Egg https://en.wikipedia.org/wiki/Dragon%27s_Egg
- aortega 4y agoI read somewhere (if someone remember it, please tell) a short history about life in neutron stars. It would be incredible fast due to the abundance of energy, with the evolution from 'stone age' to computer age happening in milliseconds. Due to being in a deep gravitational well, such life and life inside a star are forever isolated from us. Unless they discover a way to use solar flares, in fact, perhaps solar flares are their way to escape the surface of the sun.
- ars 4y agoThere's also enormous time dilation, they would appear to be moving very very slowly from our POV. It would be magical if both those phenomenon exactly counter each other (I have not run any numbers, but my instinct tells me time dilation will win out).
- idiotsecant 4y agoI think a neutron star would have time dilation below 2x. Would be interesting at our time scale, but on the order of magnitude we're discussing of the increased chemical speed i think it would just be noise.
- ars 4y agoA neutron star is right on the edge of being a black hole, which has infinite time dilation. A neutron star should have very very high time dilation.
- aortega 4y agoThere is a big difference between infinite and very high gravity. Neutron stars have only about 50% time dilation on the surface, as the surface is at about 50% their Schwarzschild radius.
- bmitc 4y ago> the surface is at about 50% their Schwarzschild radius Don’t you mean 100%? From what I can tell, the radius of a neutron star is about twice its Schwarzschild radius. https://www.aanda.org/articles/aa/pdf/2001/46/aah3021.pdf https://www.aanda.org/articles/aa/pdf/2001/46/aah3021.pdf
- rollcat 4y agoPhotino Birds immediately jumped into my mind. https://xeelee.fandom.com/wiki/Photino_Birds https://xeelee.fandom.com/wiki/Photino_Birds https://en.wikipedia.org/wiki/Xeelee_Sequence https://en.wikipedia.org/wiki/Xeelee_Sequence
- itronitron 4y agoReminds me of a thought I had after learning that it takes about 100,000 years for a photon to escape from the interior of a star. That is a long time, and the photons might be useful in conveying information throughout the structure of a star, in the same way that an electron propagates information through a brain. Extrapolate from there...
- at_a_remove 4y agoBuried in the first assumption is the question of structure. Instead of chemistry, which I will refer to only by analogy, let's imagine Tinkertoys, the old wooden ones. 0) A tinkertoy ball with zero holes can connect to nothing. It is a monad. It is boring. You can build nothing with it. This is rather like a noble gas. (Hahah yes you can build a cage around Xenon very clever thank you move along) 1) A tinkertoy ball with one hole can connect to another tinkertoy ball. If you have only these, well, you can form pairs with them, but nothing beyond the pairs. This looks like diatomic molecules. You can jumble them about but you cannot build a larger structure with them. Another dead end. 2) A tinkertoy ball with two holes can connect with two other tinkertoy balls with the same number of holes. If this is all you have you can build a long chain, as long as you like. Were it not so ruthlessly hungry for other electrons, ozone, which is to say three oxygen atoms, is a very flawed example. Sulfur, the next Group VI element, is better ... you can make chains of six to thirty sulfurs rather easily. Let me pause here. This is really a fundamental question: can you do anything interesting with this chain of sulfur atoms? Are there fascinating Van der Waals self-interactions? Can you effectively "knot" these chains, forming a higher level structure? This is the absolute bleeding edge. I propose that you need to hit ... 3) Tinkertoy balls with three or more holes. At that point you can form branching structures or a flat plane, and so on. This would be your nitrogens and phosphorus-analogues. My general thought is that, whether you have whole atoms with valence electrons, or wads of nuclei in a neutron star, whatever "chemistry" or equivalent is going on, you need three holes, or the ability to form three connections to other components, to create structure more than a humble chain, and that these connections must be relatively stable. If there is a chemistry analogue occurring on or in a neutron star, or some kind of strange plasma, or really anything, you must have a minimum number of connections to form a large enough structure to be more than just isolated bits of matter. I will allow that the "chain" model of just two connections might lead to something, but I wouldn't lay money on it. Granted, I'm a fan of Forward (and his son's work as well), but my guess is that the nucleonic matter alone wouldn't support those kind or number of connections, or "bonds," as fun as it is o think about.
- monkeycantype 4y agoChains of amino acids can form interesting proteins by 3d folding a 1d chain, so I wouldn't give up on your two hole tinker toys so quickly. Perhaps 2 hole node structures will never dominate in an environment with 3 hole nodes, but in an environment with only 2 hole nodes, 2 holes are the only game in town. I think we're going to find life everywhere, and everywhere life will have constructed itself from the best tools available - the most efficient physics and chemistry in that environment, but that the minimal requirements for a toolkit that life can use to fight against entropy will be much lower that the decadent luxury of the CHONPS toolkit we enjoy.
- deleted 4y ago[deleted]
- superkuh 4y agoThe year is 2024. After years of gravity assists from the inner planets Solar Probe+, er, Parker Solar Probe, slips into a planned series extremely close passes only 9 solar radii from the sun itself. The plan is for it to become the first human object to directly interact with the magnetic fields and plasma of the outer corona. This would be the story of the operators of the the Advanced Technology, er, Daniel K. Inouye Solar Telescope (DKIST) in the day of and years after their unexpected discovery of persistent seemingly life-like patterns of kilometer scale plasma and magnetic fields seemingly triggered below and overlapping in time with the Solar Probe+ perihelion. The life-like patterns of bright spots are found in the cool molecular layer of the chromosphere below the transition region. The temperature in this layer is so low that many diatomic molecules exist at equilibrium. This is where the gradient of thermal pressure to magnetic pressure is greatest and charged particles undergo "anomalous acceleration" previously unexplained by any detailed mechanism. http://erewhon.superkuh.com/Plasma-beta-depending-on-the-height-in-the-solar-atmosphere-Adopted-from-Gary-2001.ppm.png http://erewhon.superkuh.com/Plasma-beta-depending-on-the-hei... [The beta of a plasma, symbolized by β, is the ratio of the plasma pressure (p = number of particles*Boltzmann's constant*temperature) to the magnetic pressure (p_mag = magnetic field²/2*magnetic permeability).] The story would be about the process of science and discovery seen through the eyes of the DKIST and other observatory technicians [not: about the personal and political fallout experienced by the scientists and technicians of DKIST as the various postdocs in the labs compete compete to try to figure out if the patterns really are life and if so what can be learned from them]. As part of this it is also about the science involved in imaging and reconstructing ~50km long bright spots just above the surface of the brightest object in the solar system. After lots of exposition about zeeman splitting, the hanle effect, poynting vectors, crossing number and other topological considerations the shape and nature of the aliens as actual life would be clearer. The bright points come into being as a result of tension in field lines causing magnetic reconnection creating discrete plasmoids with a definable magnetic helicity handedness. In order to keep stable the plasmoids have to shed magnetic helicity to the solar wind to keep their internal magnetic dynamo from stopping. This requires utilizing opposite helicity magnetic fields that rise from the solar dynamo to the the photosphere below. As more resources are allocated and data is collected it is found that the plasmoid lifeforms are composed of dynamic arrangements of many plasmoids stuck together in patterns that "eat" opposite sign helicity magnetic flux tubes emerging from active regions. [This process would conclude with shedding single soliton waves via magnetosonic soliton conversion into shock waves that themselves break down into trains of soliton waves that propagate out into the solar wind? Soliton formation requires a balance between convection and dispersion.] The origin of nanoflares, unexplained km scale coherent radio emissions, non-thermal broadening of spectral lines in the transition region, the gamma ray excess and 40 GeV dip, and why the corona is hotter then the surface are finally explained. Along with this human accomplishment and understanding of the outer sun references should be occasionally made to the uncertainty about the the processes occuring above the tachocline but below the photosphere. Even more mysterious is the dynamo itself in the core known only through inferences made from "G" vibrational modes of the star discovered through doppler measurements of the photosphere surface.
- hypertexthero 4y agoThis reminded me of Star Maker by Olaf Stapledon, an excellent book from 1937: http://www.astro.sunysb.edu/fwalter/AST389/TEXTS/StarMaker.pdf http://www.astro.sunysb.edu/fwalter/AST389/TEXTS/StarMaker.p... > One night when I had tasted bitterness I went out on to the hill. Dark heather checked my feet. Below marched the suburban lamps. Windows, their curtains drawn, were shut eyes, inwardly watching the lives of dreams. Beyond the sea’s level darkness a lighthouse pulsed. Overhead, obscurity. I distinguished our own house, our islet in the tumultuous and bitter currents of the world. There, for a decade and a half, we two, so different in quality, had grown in and in to one another, for mutual support and nourishment, in intricate symbiosis. There daily we planned our several undertakings, and recounted the day’s oddities and vexations. There letters piled up to be answered, socks to be darned. There the children were born, those sudden new lives. There, under that roof, our own two lives, recalcitrant sometimes to one another, were all the while thankfully one, one larger, more conscious life than either alone. > All this, surely, was good, yet there was bitterness. And bitterness not only invaded us from the world; it welled up also within our own magic circle. For horror at our futility, at our own unreality, and not only at the world’s delirium, had driven me out on to the hill.
- negativelambda 4y agoThis reminds me of a paper [1] where they find that... "In the redshift range 100<(1+z)<137, the cosmic microwave background (CMB) had a temperature of 273-373K (0-100 degrees Celsius), allowing early rocky planets (if any existed) to have liquid water chemistry on their surface and be habitable, irrespective of their distance from a star." [1] https://arxiv.org/abs/1312.0613 https://arxiv.org/abs/1312.0613
- hoseja 4y agoThe monopoles and cosmic strings kinda ruin this. But there totally might be life in the star cores made of plasma magnetohydrodynamic interactions, in fact I'd be surprised if it weren't common. And the lifeforms would be completely isolated from outside universe, by the turbulent nature of outer star layers, by the enormous gravity well and the comparatively absolute cold and vacuum of empty universe. None of the linked sci-fi stories have such life as subject (at best The Truth but that one has a creature that can exist on Earth long enough to be perceived instead of violently dissolving into loose cooling gas in microseconds), probably because it's very hard to make it interact with human characters, but it's the simplest form I can think of.