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When the Fermi Paradox was first posited, scientists and engineers seemed to believe that interstellar travel was soon to be technologically achievable, a few d
by stephc_int13 1y ago
When the Fermi Paradox was first posited, scientists and engineers seemed to believe that interstellar travel was soon to be technologically achievable, a few decades, maybe centuries for the less optimistic. Progress around space propulsion has kind of stalled since then and we should maybe question the possibility of interstellar travel as this would give an easy but unpleasant answer to the famous paradox.
- shireboy 1y agoRight- “where are all the aliens?” is answered by either “they don’t exist” or “they do but physics of the universe prevent them from moving between solar systems.”
- VladVladikoff 1y agoThis feels very defeatist to me. Technology continues to advance, exponentially. And there are hypothetical ultra fast space travel technologies that we haven’t yet been able to fabricate but could theoretically in the future. e.g. Alcubierre warp drive.
- losteric 1y ago> Technology continues to advance, exponentially Why should we believe it will continue to advance exponentially? And even if it does, we many find none of the hypotheticals pans out - perhaps we advance exponentially and there is nothing feasible to reach even 0.01c
- notTooFarGone 1y agoYeah it's always quite naïve to say technology will be always exponential. We only had like a few thousand years - if it's logarithmic we wouldn't know it for the next 10000 years.
- nirav72 1y agoMore like technology evolves in spurts. Huge gains within a specific area for 2-3 decades and then only small incremental advancements for the next 2-3 decades.
- justinator 1y agoMore like technology evolves during global wars. Fixed that for you. Rev up those stealth fighters!
- nobody9999 1y ago>More like technology evolves in spurts. Huge gains within a specific area for 2-3 decades and then only small incremental advancements for the next 2-3 decades. I'd expect that the time scales between spurts, while getting shorter over the past 350 years or so, were generally much, much longer. We first started using stone tools more than 2.5 million years ago. We didn't start effectively using fire for another 500-750k years. It was another 1.75 million years before we began harvesting seasonal "crops" we identified in our nomadic travels, and another tens of thousands of years before we founded permanent agricultural settlements. Doing so (and the food surpluses enabled by such) allowed for specialization and R&D into stuff that wasn't directly related to food production. That really kicked off a technological spurt, which included writing -- a technology that was, perhaps, the biggest step forward, until Liebniz/Newton's Calculus. Given the immaturity of our current understanding of physics (Standard Model/General Relativity), biology (DNA research) and the like, it seems we're likely to continue without another spurt for quite some time. I, of course, could be wrong. But since history is often a good guide to the future, I don't think so.
- krapp 1y agoIf the Alcubierre drive were possible, some civilization would have already discovered it, and we would see evidence of its use. This is certain to be the case with any kind of FTL travel, if such a thing is even possible. But when we observe the universe we see nothing. Therefore either no advanced life exists in the universe besides ourselves, which seems unlikely, or none have spread to space in any significant degree and FTL is either impossible or so difficult no one bothers. There doesn't seem to be a secret third thing that both satisfies our observations and obeys known physics.
- oneshtein 1y agoGeminga?
- krapp 1y agoEverything I read tells me it's a gamma ray pulsar.
- oneshtein 1y agoSomething like Alcubierre drive must move fast (0.1% of c at least), be very heavy and dense (to create protected environment inside), and emit lot of high energy gamma rays because a spacetime with negative energy will accelerate light a lot.
- deleted 1y ago[deleted]
- justinator 1y ago>Technology continues to advance, exponentially. Currently focusing on imaginary money crypto schemes and ML chatbots whose data centers use as much power as entire US states, sorry.
- freakynit 1y agoThe fabric of spacetime itself sets the ultimate speed limit. Nothing can locally move through it faster than light. For example, gravitational waves ripple across the universe at light speed. Anything that exists within spacetime is bound by this rule. The only odd exception people point to is quantum entanglement, but while the correlations appear instantaneous, they can’t be used to send information faster than light. Sending matter is distant second. So, if we ever hope to travel faster than light, we wouldn’t do it by "outrunning" gravity. Instead, we’d need to find a way to manipulate spacetime itself, like bending, warping, or reshaping it ... since that, in the first place itself, is what is defining the limits of motion.
- oneshtein 1y agoSo c is the speed of light in the fabric, right?
- freakynit 1y agoI believe "c" is the upper limit of allowed speed in this spacetime itself. Light just so happens to be the fastest of all entities in this spacetime. Thus, we see "c" as the speed of light. and not the max. speed limit imposed by the spacetime.
- Ekaros 1y agoI think our recent forays to microscopic and sub-microscopic things like computers have really distorted our views. Just look at something like EV. Give say 10x efficiency(very high) increase and we are actually still faraway from even interplanetary travel. Physical world is big and getting from one point to other takes lot of energy and involves lot of mass.
- Rover222 1y agoEspecially if we are actually on the cusp of ASI from self-improving AGI systems. That seems like the most likely scenario where technology emerges that we cannot currently fathom. (Big IF there, I know)
- imoverclocked 1y agoI dislike either/or answers in such open-ended scenarios. It points to our lack of humility in the vast unknown. eg: maybe they exist(ed) but once a civilization gets advanced enough to build FTL-like travel, they invent AI and use it for warfare and then soon cease to exist. This would mean there are potentially many civilizations (and AI?) that are budding and could travel through the universe. eg: We aren't in an interesting enough place to bother visiting. eg: they exist and know about us but have "prime directive" (Ala: Star Trek) laws that state they can't make contact until we reach a stable enough civilization to invent warp drive (or some other advancement.) eg: There is some exotic reason that our pocket of the Milky Way is un-navigable.
- bluGill 1y agoWe know enough physics to rule out any ftl travel. Assuming that is correct which seems very likely they can't get here, even radio signals is question able - even if radio signals can get here either they have already passed and their civialization (sun) is dead or ours will be dead by the time they arrive.
- oneshtein 1y agoCherenkov radiation is a proof, that FTL is possible. We just cannot accelerate enough. However, «burps» from blackholes are proof that blackholes can do that. To achieve singularity, outer layer of blackhole core must spin at a FTL speed anyway.
- Aerroon 1y agoOr: we're the first (or among the first). The history that led to space travel (modern human technology) has passed through an insane amount of unlikely scenarios. A few of these: * Astronomical: the sun is unusually calm for a star. Jupiter blocks comets. Saturn blocked Jupiter from destroying the Earth. * Earth is 4.5 billion years old. In the next 0.5-1 billion years Earth will become unhabitable because the sun's luminosity is increasing. We're in the twilight years of the (life-supporting) planet. * Above point + think about all the species that came before us. Life appeared 3.5-3.8 billion years ago. It took that long to get to humans. * Dinosaurs got wiped out. Would humans have even evolved if a cosmic event hadn't cleared the board? * We think that human ancestors dropped down to about 1000-100,000 individuals about 900k years ago. There's also the question of how many sun-like stars in terms of metallicity there are that preceded the sun. Our sun inherited a lot of heavier elements from a previous generation of star(s). Add all of these together and we might be early to the party.
- brabel 1y agoI believe this argument is fallacious. There could be infinite other ways a species could have evolved to acquire space technology. A smart dinosaur that evolved to use arms and tail could perhaps have built an industrial civilization. They would’ve been now 100 million years old! Imagine the progress. Them being wiped out probably just delayed civilization by millions of years.
- rini17 1y agoWell, dinosaurs learned to fly instead. And perhaps they ended in a local maximum that made them survive and thrive but did not allow development of larger brains. Not that humans with their troublesome egos are necessarily anywhere near global maximum.
- Aerroon 1y agoYes, but they didn't. I do concede that it's possible that they could've. But even that doesn't guarantee anything. Modern humans are ~100k years old. It took us nearly all of that time before we discovered agriculture. And it still took thousands of years after that to end up with industrialization. Before then our societies barely improved. It's entirely possible that if society had gone differently that we could've delayed or avoided industrialization altogether. The same could've happened with dinosaur-people.
- cryptonector 1y agoOr by "none exist right now nearby". If there are technological aliens 3 bly away and 3 bya, we won't likely discover their signals. If there are technological aliens 10 ly and 10 ya then we're extremely likely to pick up their signals (if they emit any), but they're not likely to come here -- not anymore than we are to go there. The Fermi paradox is most easily understood as "the probability of two concurrent technological species in different but nearby star systems is vanishingly small". For all we know there have been thousands of technological species in our galaxy, but never two at roughly the same time and roughly close together, and never will be.
- BobbyTables2 1y agoI’ve always wondered — magnetism seems kinda crazy — how are two objects not touching but exerting a force(?). Practically witchcraft… Without electricity, how well would we understand it? Just that some mysterious rocks that stick? Wonder if one day in the distant future we’ll discover a new force we never imagined.
- infradig 1y agoHow is two objects not touching but feeling a force crazy? Isn't that what gravity does but everyone's ok with that
- ljlolel 1y agoGravity is crazy
- praptak 1y agoAnd is a force only in the non relativistic model.
- DonHopkins 1y agoVelcro too.
- Yokolos 1y agoA lot of science is crazy but real. Are you not awestruck by the weird ways the real world behaves? Where's your wonder?
- mannykannot 1y agoWell, it continued to bother Newton. Here, he seems to be foreshadowing the concept of fields: "It is inconceivable that inanimate Matter should, without the Mediation of something else, which is not material, operate upon, and affect other matter without mutual Contact... That Gravity should be innate, inherent and essential to Matter, so that one body may act upon another at a distance thro’ a Vacuum, without the Mediation of any thing else, by and through which their Action and Force may be conveyed from one to another, is to me so great an Absurdity that I believe no Man who has in philosophical Matters a competent Faculty of thinking can ever fall into it. Gravity must be caused by an Agent acting constantly according to certain laws; but whether this Agent be material or immaterial, I have left to the Consideration of my readers." https://plato.stanford.edu/archives/win2008/entries/qm-action-distance/#ActDisCoExiNonSepHol https://plato.stanford.edu/archives/win2008/entries/qm-actio...
- treyd 1y agoWe do know how to build interstellar-capable propulsion. It'd still be a generational ship but we know how we could do it within the span of a few human lifetimes. Building them is a matter of organizing the resources to actually make it happen, and we haven't had the collective will for anything like that yet.
- SoftTalker 1y agoI’d be pretty pissed at my parents if I was born on a Starship and condemned to die on it too. Imagine living your entire life in a Winnebago and you can’t even go outside.
- papascrubs 1y agoI follow what you're saying, but many folks on this planet have far less opportunities than such a trip might provide. Guaranteed food, housing, access to cutting edge healthcare, a likely united community. I'm assuming these ships would be fairly big. It would definitely be different but-- would it be as bad as we think?
- saulpw 1y agoIt would be better than living your entire life in a literal cage on earth. But I think it would be worse than even being a slave on earth. A slave can touch grass and hope to run away. A person born on a generational ship would be effectively enslaved (to perform necessary ship duties). You mention 'cutting edge healthcare', but on earth that requires the substantial and diverse resources of an industrial civilization. The research of millions of people and the infrastructure to breed nuclides and manufacture precise machinery. Does this generational ship have a modern chip fab on it!?
- seabass-labrax 1y agoUnfortunately, I suspect that any starship that could bring with it all of those services would also bring with it the economic and political strife of Earth. The are lots of examples of democratic states turning into oligarchies or worse in recent history so that can't work in it's current form at least. The closest analogue in the real world to the ideal that you describe is, I think, Cuba. It does guarantee food and housing, and it does have a remarkably advanced healthcare system plus what is reportedly a united community. Perhaps most interesting of all, it's politically isolated like a starship would have to be by its nature. Even then, one would have to be either pretty brave or desperate to go along on the journey, as modern Cuba has only been around for half a century and that's at the absolute minimum of an intergalactic starship's practical mission duration.
- Razengan 1y agough the Fermi "Paradox" is pseudoscientific tripe standing on a ton of naive assumptions and it's depressing how often it's seriously invoked.