Also, we've realized the scientific reality that traveling faster than light is likely impossible, and the vast distances to other habitable planets would mean tens of thousands of years of travel even with the most efficient technology.
Interstellar space is also hostile to life, and any life present at the destination will not use the same DNA coding for protein (if gene expression even works that way).
We also do not yet have the technology for a complete survey of nearby habitable planets.
>Also, we've realized the scientific reality that traveling faster than light is likely impossible, and the vast distances to other habitable planets would mean tens of thousands of years of travel even with the most efficient technology.
This makes for more epic story telling though. I've seen sci-fi stories span eons due to the vast distances limited by speed. Even at light speed it still takes a huge amount of time.
It rarely has to do with the possibility of the genre actually happening in reality. A story is good because it is riveting and the backdrop (whether sci-fi or fantasy) is just icing on the cake. Look at Harry potter and practically every fantasy story out there.... none of those stories have any chance of happening in our current reality... yet they are popular.
I think the answer for as to why there's less interest in sci-fi is pretty mundane. It's like genetic drift, but this one is cultural. For no reason at all our interests just shift because of luck. There happened to be more good stories written in the fantasy genre and that's the direction everything shifted.
Tbf though the MCU was more sci fi than anything and that every genre out of the water in every medium all the way up until endgame. Say what you want about it but the popularity of that universe dwarfed everything else in the last decade... which goes to show that it's likely mostly just drift.
> >Also, we've realized the scientific reality that traveling faster than light is likely impossible, and the vast distances to other habitable planets would mean tens of thousands of years of travel even with the most efficient technology.
>
>This makes for more epic story telling though. I've seen sci-fi stories span eons due to the vast distances limited by speed. Even at light speed it still takes a huge amount of time.
> and any life present at the destination will not use the same DNA coding for protein (if gene expression even works that way).
Well, that could be worked around in the world building. My favorite SF-friendly scenario would be if life originated in the Sun's natal cluster (perhaps not around the Sun itself), with tens of thousands of star systems, and spread between them before the cluster dispersed. Presumably panspermia would be much easier in such a situation because the stars are closer together and because maybe residual gas could help particles get trapped near other young systems. In this case all the "infected" systems could have the same coding.
A nice consequence of this scenario is it's compatible with the Fermi argument: even if origin of life is unlikely, it just had to happen once here, and so it not happening elsewhere in the galaxy (or even visible universe) is not a problem.
Science Fiction doesn't have to be fantasy, it can be speculative. But if your setting or plot relies on something we know to be scientifically untrue, and you don't put some effort into explaining why it somehow works in your setting, it's fantasy and not speculative.
Someone like Asimov never considered his books to be fantasy and that he could just insert whatever he wanted with no justification. In fact, he never considered sci-fi to be a genre, he always argued it was a setting and that his most famous stories were detective stories in a sci-fi setting. But detective stories don't work if your world isn't grounded in something real. Otherwise the reader can't reasonably build their own theory or deduce the answer because it's based on what the author thought was cool and not what logically connects.
The appeal of something like The Expanse just falls apart if you introduce a FTL engine just because it makes for a more dramatic story moment somewhere in the plot unless there is some serious justification as to why the author didn't just break all the rules of their world (which is supposed to be our world, but in the future).
"But detective stories don't work if your world isn't grounded in something real."
No, it just has to be grounded in something consistent and if the book starts by explaining the mechanics of the world(or is in a world with known mechanics), a detective story very well can work.
It can’t be too different from what people are familiar with. So it has to be consistent with itself and with reality.”It’s like our reality except …” but the except part (faster than light travel, mind reading, time travel, dragons, magic, etc) can’t get arbitrarily complex or unreasonable or the reader will be lost or confused.
"can’t get arbitrarily complex or unreasonable or the reader will be lost or confused."
Indeed, but that is always the challenge of a writer. But if you introduce magic in your story, and you do it in a way to show the limitations and what is roughly possible, then you can give hints later, if there was a murder with the help of a magic trick. But I actually think I only ever read one detective fantasy story
It mostly works, but in one instance there was a surprise fantasy ability, that I could have not guessed before. But the actual murderer in the end, there were enough hints that gave them away despite magic, as the skills were explained and then you could combine.
True but at that point objects travelling faster than sound had been demonstrated.
It was just hard to engineer a manned plane that could do it. For example during WWII the V2 rockets travelled much faster than sound. They were just unmanned. Or more simple, bullets were supersonic for longer too.
What I mean is, nobody thought the sound barrier was a hard limit we could never break.
A magic unobtainium drive which works in a consistent way is fine, just call it “hyperspace” or whatever
There’s a difference between hard sci-fi and soft sci-fi, but they are both still sci-fi, you can tell optimistic stories of the future with a “battle drive”, as long as you keep it consistent. If the drive cancels relativity effects and allows travel at 5000c that’s fine. Just ensure you travel at 5000c, no hoping across the galaxy in a few days, but travelling to another star in a few days or even hours is fine.
> But if your setting or plot relies on something we know to be scientifically untrue, and you don't put some effort into explaining why it somehow works in your setting, it's fantasy and not speculative.
Agreed but only because "some effort" could be as little as a single paragraph.
> But detective stories don't work if your world isn't grounded in something real. Otherwise the reader can't reasonably build their own theory or deduce the answer because it's based on what the author thought was cool and not what logically connects.
If you only change a tiny bit, this isn't a major issue.
> The appeal of something like The Expanse just falls apart if you introduce a FTL engine just because it makes for a more dramatic story moment somewhere in the plot unless there is some serious justification as to why the author didn't just break all the rules of their world (which is supposed to be our world, but in the future).
That specific story falls apart but you could have lots of thematically similar stories with FTL. No need for "serious justification" unless you're trying to pull it out of nowhere halfway through the plot. If it's there from the start, there's no problem.
> No need for "serious justification" unless you're trying to pull it out of nowhere halfway through the plot. If it's there from the start, there's no problem.
Yeah I think most readers care more about consistency than realism. Being completely realistic makes consistency easy but a harder sell in terms of entertainment.
Maybe one way to view consistency is modelling the story world as a network of criss-crossing character threads. Where one axis is time and the other(s) are uh something? Anyways, consistency is how predictable (smooth / linear) the thread is. We follow the main character's thread pretty closely so that thread is allowed to suddenly curve (plot twist) without risk of losing the reader. We only catch glimpses of the supporting cast / antagonist so those have to be either predictable or the narrator has to backtrack and reveal any twists where necessary. And maybe how intricate yet well-behaved this network appears is what gives the feeling of stories coming alive. Or maybe I'm just on too much caffeine and ranting.
Start trek transporters work because of a Heisenberg compensator. Great, no idea how it could possible work but it’s enough to know it does.
The typical poorly received uses aren’t when the cre beams down from orbit, or even when they can’t beam down, it’s when they de age people and retrieve their pattern from the buffer to cure an illness, and never do it again, or when they beam light years away for a throw away story element.
30s to 60s, sci-fi wasn't just driven by the "makes for great stories", but by the optimism for scientific advacements and the idea that these could get within reach in the future.
It was "science fiction" and not merely "space fiction".
Presumably these are equally likely because you could build a DNA-printer and thereby create a dragon of some sort (not sure if it could have fully functional fire breathing though)?
Dragons are physically impossible in many more ways than the firebreathing. For one, things that large would probably struggle to fly. We can make larger things fly, but have to cheat using jet (or rocket!) engines to generate incredible thrust in ways not typically accessible to living beings.
And now I'm picturing a dragon with bombardier-beetle style pulsed jet boosters. And while I'd typically question your assumptions of how big dragons need to be in order to deserve the name, I'll assert that quetzocoatlus nothropi[1] was big enough.
"Dragon" as a classification is odd, because when you look at every kind of mythological creature that gets classified as such nowadays, sometimes from cultures that wouldn't have recognized the concept, you find that they have little in common beyond some vaguely reptilian vibe and being scary.
And I'm sorry but that thing is too goofy looking to be considered a dragon.
That's begging the question. We don't need to look "at every kind of mythological creature that gets classified as such nowadays" from "cultures that wouldn't have recognized the concept".
One could stick on those classified as such in western culture - which is where the fantasy novel about dragons and knights and spells and the rest are based on.
And in there, dragons have quite specific characteristic and vibes, as evidenced from medieval iconography of St George to countless fantasy book covers and illustrations.
But if we do expand the set under consideration then I'd suggest they do in fact have specific things in common. Large flying carnivorous reptiles. That won't cover all the various edge cases but I think it describes the vast majority of the popular usage of the term.
That definition would imply that sufficiently large flying dinosaurs qualify as dragons. And at least personally I think I agree with that conclusion. Dragons aren't purely fantasy, they're merely extinct (and never breathed fire IRL).
Hence eco-systems, yes. But that's probably a harder problem than radiation shielding + hibernation. You'd still need the radiation shielding but it would be far, far more of it (because non-local).
These are interesting problems to think about, right now they are solidly SF but dragons are and always will be fantasy because physics says they can't exist in the way they are described. But you can't 100% rule out that one day descendants of humanity will visit the stars in person, assuming we don't blow ourselves up first.
That's one of the main reasons I dislike Musk so much: he takes people motivated by positive dreams (a clean planet, off-world travel and living) and then subverts their energy for grift. But 'DOGE' has shown the world who he really is, the mask is off now and anybody still empowering that asshole is co-responsible.
> physics says they can't exist in the way they are described
If we assume advanced genetic as well as bio engineering that admits the possibility of self reproducing cybernetic organisms that closely match many or all of the key characteristics. I'm not sure it's actually a cyborg if the lineage is fully independent without involving any technology external to the species but I use the term there because that's the easiest way to communicate the idea.
No, then it still wouldn't work. Not until you use that other thing to get you to a planet where gravity is low enough that a dragon would be able to take off. The whole power-to-weight and wing-surface-area-to-weight ratio simply does not work. It (barely) works for bats though some of them can be of impressive size. The idea that something the size of a dragon can fly with that size wings on Terra is something that I do not believe is supported (hah!) by physics.
I think you're making an awful lot of assumptions there and have failed to provide even ballpark specifications for the thing you're supposedly refuting. Weight seems to be a secondary characteristic related only to size. There are also plenty of examples of "small" dragons in fantasy literature.
We've already got examples of dinosaurs that come fairly close to qualifying so I'm sure something vaguely in the ballpark is within the realm of possibility. Exactly how close to the mark though I have no idea.
For example, what would you make of something visually resembling a massive western dragon but with a largely hollow body? I don't think that would disqualify it in most people's eyes. Pushing the concept a bit farther could yield something vaguely like a living cross between a hot air balloon and a deep-sea anglerfish with a weaponized tail.
Vaguely related to that hypothetical, we've got examples in the fossil record of 2 foot wide dragonflies estimated to have weighed in at under 150 grams. There's a pretty large solution space to explore here.
Sorry, not going there. The physics of the impossible are not for me to take apart but for you to show. I've postulated ways in which you could get to other solar systems, I don't see anything here that would lead to a dragon as it is commonly described in fiction. Fire spewing, heavier than air, intelligent and willing to let themselves be mounted and directed by humans, that's the bar.
Archaeopteryx would have you for lunch long before you realized that it doesn't spit fire.
Well you've decided that it's impossible but you certainly haven't convinced me of that fact (neither am I certain that it is possible though).
I'm not even clear what the criteria are. We've got examples in fiction that run the gamut. Even limited to fairly traditional post-Tolkien western high fantasy examples of creatures with a long neck, two wings, a distinct abdomen, and a tail we've still got concrete examples ranging in size from a small lap dog up to larger than a McMansion. Plenty of reasonably canonical examples don't spit fire (although being able to certainly furthers the general vibe). And weight? As I said earlier, that's (imo) solidly in the domain of secondary characteristics.
Semantic arguments aren't any fun (and are largely pointless). Is Pluto a planet or not? Unless it's a technical discussion where the distinction matters for some reason, who cares? What matters is if Pluto fits the pattern that you (ie the people conversing) care about.
Hence my posing the example of a particularly buoyant variety of dragon. I think most people would consider it to fit the pattern well enough but I'm sure there would be at least some disagreement.
Also as long as we're talking about wild far future sci-fi possibilities such as visiting other stars in person then you can't rule out dragons in the form of a wildly advanced, needlessly decadent military technology show piece. Something like a nuclear powered bio engineered cyborg for use as some sort of fighter jet. (Apologies if I just inadvertently ripped off some anime I've never heard of.)
Creating some sort of genetically-engineered dinosaur-derived ‘dragon’ may be more plausible than actually reaching another star system. It’s not going to breathe fire though.
> Not sure your point. It's fiction. Are we closer to finding dragons, faeries, or magic?
No, but we've become increasingly superstitious, and cultish. A lot of the day to day parts of sci-fi (screens everywhere , instant communication) have become reality so it's not as exciting anymore. Sci-fi no longer serves as escapism. Anymore, it reminds us of our limitations.
With D-D fusion it might be possible to "live off the land" between the stars which probably have numerous interstellar objects of various sizes between them with a much larger cumulative mass than planets orbiting stars -- and it may be possible to completely disassemble those kind of bodies which are much richer overall in carbon, hydrogen, oxygen and nitrogen than terrestrial planets.
A species with that kind of capability would be able to visit another solar system in 10,000 or so years but might care less to mess around with dry little solar system bodies like the Earth. The case against "grabby" aliens is that Ceres and Pluto are still here, not that we can't find evidence of them on Earth.
I like to imagine that if that kind of interstellar traveler were to visit Earth it might take them a few decades to perfect a "reverse space-shuttle" because they'd gone 10,000 years without doing anything like that... And they can't just 3-d print one out of 10,000 year old plans because they've improved their 3-d printers to print the stuff they've been printing all that time better.
I feel like for this reason we should be focused on colonizing asteroids rather than the moon or mars. We can do various tricks to get artificial gravity via centrifugal force. For example if the asteroid is solid enough, we can consider putting it into a spin. If it's not solid enough, we can consider laying a track around the circumference and/or boring a tunnel around the circumference and essentially having the habitat(s) constantly rotating around the asteroid.
Exactly. Those kind of people could support much larger populations than the Earth with a lifestyle they find comfortable in interstellar space and would look at living on Earth at best the way we look at living on Mars.
There is a scene in Pirates of the Carribean where captain jack is stuck in a void surrounded by duplicates of himself. It is his hell. As we have biult better and better telescopes we realize that as we expand into space we will be stuck talking only to ourselves, at least for a few thousand generations.
When they turned LIGO on i wanted to see warp drives whipping around. But all we saw was distant black hole mergers; interesting but not exactly a star trek moment. When areicebo fell and was not immediately rebiult, i realized that most people just dont care about ever meeting another civilization. Even if we did find one it wouldnt change much here on earth. Most people dont care about climate change. They dont care about anything beyond their own lifetime. What matter will aliens be if they are a thousand lightyears away? So people dream now about other things, about grimy politics and alternative history.
>When they turned LIGO on i wanted to see warp drives whipping around. But all we saw was distant black hole mergers; interesting but not exactly a star trek moment.
• The LIGO methodology is to look for hyper-specified patterns in voluminous reams of apparent 'noise'. It wouldn't be unfair to call it an extensively aggravated search for what one is looking for. That's okay, so long as they provide the stats to back up the non-noisiness of what they turn up. (I'm not a stats person and can't debate that, and. I trust their caliber enough that I don't feel the need to). But to your point, if there are other signatures lurking in LIGO data _that they don't know already how to look for_, then there is no reason why a paper would have gotten produced describing it since the first GW detection in 2015.
• Now, take this for what it's worth in terms of fragmentary information relaying - But at the first Sol Symposium in 2023 at Stanford, I can tell you that in podium-level banter between talks (perhaps it was Q&A and the like IIRC) it was asserted that the LIGO consortium was not allowing studies (read: not allowing access to its data) where the investigator's intension was related to UFO / UAP phenomena (like, extrapolating here, looking for signatures correlated with external reports of UAP sightings). If that claim was borne out, than perhaps the LIGO consortium is just doing preemptive reputation protection in not allowing such studies to kick off with its name associated with it. (One could attempt to follow up with astronomer Beatriz Villaroel for a lead on who said that or if there's substance to that research policy claim)
But my point is, between these two bullet points, you are afforded a complete 'empty set' - and decidedly not a 'negative result' - on whether or not LIGO has detected signatures of a 'warp drive' or other some such non-prosaic phenomenon.
If LIGO can detect mergers at billions of lightyears, i doubt they could ignore the "sound" of the NCC-1701 passing through our solar system. Proper access or not, there are enough scifi geeks with access to LIGO data that someone would get the word out.
Again, raw LIGO data is sheer noise. They have to interrogate the dataset with their hypothesized candidate signal signature, natural or otherwise, and see if it ‘responds’ with a hit. In the case of black hole mergers, they had an idea - a candidate model - of what to look for. In the case of a warp drive, could they even guess a signature to interrogate the dataset with?
And to the extent that the -1701 patrolling Mars-Venus might manage to ‘stick out like a sore thumb’, what about the relative blip of a Sh'Raan class embarking on some fresh surveying out of 40 Eridani A?
Rebuilding it would cost maybe half a billion dollars. Give ICE an unpaid week off and job done. Maybe not the absolute best way to spend that money on science, but I fear the actual outcome is “it’s not cost effective so we’re not going to spend it on any science.”
I really find it hard to understand how people confuse science fiction with reality. I love Tau Zero - I first read it over 40 years ago - but it’s fiction, ffs.
Also they have trouble stopping in Tau Zero so they have no choice going further than they planned. It's one of the best sci-fi novels of all time, read it!.
That Bussard Ramjet, though, is thoroughly discredited. It can't possibly work. Hydrogen hydrogen fusion is a terribly slow nuclear reaction and if you had to stop the gas to give it enough time to react, you'd end up stopping the rocket not accelerating it. In fact, the most credible use of that kind of magnetic scoop is as a brake!
Stop to consider them for what purpose? Thinking they're cool? Yeah they're cool. But they have very little to do with interstellar travel, in the way that a canoe has little to do with investigating deep-sea vents.
A small station, hosting a small number of people, orbiting very close to the surface of the Earth.
> 3,000 satellites providing Internet Service
…very close to the surface of the Earth.
> Mars rovers that run for 10+ years
On the closest planet to Earth that our equipment can survive on. Notably, we have nothing but melted slag on Venus.
> Flying helicopters on Mars
On the closest planet to Earth that our equipment can survive on.
I don’t mean to detract from the achievements of our space programs. But we have to be realistic: we’re exploring the easiest bits of our local neighborhood, that’s all.
This is motivated pessimism. We knew in the 50s that breaking the speed of light was highly unlikely. We dreamed of the stars anyway. Now we refuse to dream, or to even attempt to solve the problems (a common pattern when discussing spaceflight is people who are blatantly searching for problems, rather than solutions), because we are pessimistic, devoid of imagination, and seek to legitimise our collective depression through scientific and engineering arguments.
You don't need to break the speed of light to get to the stars. Time dilation and space contraction mean that you can get there in as little time as you desire.
Everyone you knew on earth would be dead by the time you got back, but if it's just about you, the speed of light is no limitation at all. (The rocket equation, however, presents stupendous engineering challenges.)
Time dilation and space contraction only matter if you can reasonably achieve speeds of a significant portion of the speed of light. AFAIK nobody has even come up with a reasonable way to achieve this for lightweight probes, let alone for hundred-ton ships capable of carrying humans. And let's not forget the practical problems like all photons incoming from the front being blueshifted into ultrahard radiation that would make a point blank nuclear bomb seem like a small candle.
Realistically even getting to the nearest star in less than 400 years experienced time is way way WAY out of reach for now.
Laser accelerate a lightweight probe, probe lands on alien planet and self replicates a receiver and basic robot body. Send mind in the form of information at speed of light and download into robot body.
Something roughly along these lines was believable enough for the Altered Carbon universe.
Landing from relativistic speed would be a massive engineering problem, since you won't have a laser de-celerator on the other end. And landing on a planet would seem to require a rocket, which cannot be lightweight.
Not necessarily insoluble, but a massive unsolved problem.
Show us how to build machines, create factories, mines, chip fabs, etc., smelt steel, and so forth out of those bacteria and cells and you might have a point.
So what? Dilithium + antimatter + magic space warping was enough for the Star Trek universe. The sky is the limit for science fiction.
Just in that first paragraph:
- How do you stop at the other end? There won't be a large laser array at the receiving end and a laser probe will not have enough stored energy to decelerate itself.
- How exactly do you download a mind to be transmitted? We can't do it right now to be sure, and it's not clear we could ever accurately do that depending on how finely detailed a human brain is.
- How do you transmit it reliably over several hundred light years? Background radiation alone is enough to drown out any signal after a few dozen light years no matter how good your transmission is. Also, when do you start sending? You cannot possibly know which probes survived. (you DID send out at least a few hundred probes right? Don't forget to multiply laser energy requirements by the amount of probes)
- How does the receiving end download a mind into a robot body? We can't even begin to do that on Earth, not even with worms or flies. Humans are right out.
- How do we power the lasers? Conservative estimates have put required laser power at several gigawatts at least. Current laser systems can do that in pulsed mode but only with extremely low duty cycles. Getting enough power together to supply millions of homes would be tricky to say the least. (and see the note above about needing multiple probes just to be on the good side of probability)
- How does the probe survive decades of ultrahard radiation? What about dust it will encounter at high-subluminal speeds, also for decades? The shielding for that won't be lightweight, but the heavier the probe gets the more difficult it will be to accellerate.
- The satellite which is light enough to be powered by lasers also contains the most magical 3d printer anyone has ever seen. You can't just pull the molecules for advanced processors and energy generation equipment out of the air, such a probe would need to set up significant mining industries all on its own without any human interaction.
- A basic robot body. Keep in mind that "picking up a keychain and choosing the right key out of it without dropping the whole keychain" is already a challenge for modern robots.
In short, it'll be several centuries before humanity even gets close to such a project. I'd like to be wrong, but it seems extremely unlikely anyone of us will see such a thing in our lifetime.
It is very unlikely indeed, because we are not trying. We have a world set up so as to allow a few people to accrue wealth they couldn't possibly need, by impoverishing everyone else. Where are they going to make money out of this?
>but if it's just about you, the speed of light is no limitation at all
It's a huge limitation, even just getting propelled to "big enough speed", say 1/10 the speed of light.
We barely do 1/1500 the speed of light, in unmanned probes, and only because we sling shot on Solar gravity, not as propulsion or anything, and at 1400 o Celcius, plus deadly radiation, not to mention any micro-meteor as big as a particle of dust could kill someone there).
> It's a huge limitation, even just getting propelled to "big enough speed", say 1/10 the speed of light.
If you can't even get up to 1/10 the speed of light, then you wish the speed of light was a huge limitation, but it's actually not affecting you at all.
If the point argued is solely "the speed of light is a huge limitation" (and not: "getting anywhere near the speed of light is a big issue"), I'd say accepting that "even basic much lesser speed is a huge problem" is hardly a refutation of that. Nor is it an argument towards the feasibility of the actual feat being discussed (interstellar travel).
I guess you're technically correct though: the speed of light is not an issue, if 1/10th the speed of light is already unachievable.
Don't even need to do time dilatation - just make you lifetime longer by techjlnical means (ideally almost infinite) and you will be in the next star sumystem before you figure out how to exit your VIM session.
I don't think it's motivated pessimism so much as a shifting tastes and changes in media. There are tons of SF stories with starships in movies, games and streaming platforms. It just happens to be the case that fantasy is more popular then SF at the moment where books are concerned.
That would only rule out stories based on interstellar travel, which is a tiny subset of what you can do in space. After all, you'll just end up inside another solar system that won't be much different from ours. The planets will be in different orbits but there will most likely be an asteroid belt and the effects of temperature will remain the same even if the planets are in different temperature ranges from our planets.
If earth is big enough for fantasy, then the solar system is plenty big enough for science fiction.
If you wanted to watch hard science fiction I would recommend watching anthrofuturism on YouTube who focuses exclusively on the moon.
Our astrophysicists don't even know why the universe is expanding, don't know that Lambda CDM is correct, don't know if things are universally consistent, yet we're so damned sure this is it.
We don't even know that this isn't a simulation. Not non-falsifiable, sure. But we're convinced we're bound to this solar system with our crude tools and limits of detection.
One new instrument could upset our grand understanding and models. Maybe we should wait until they get better hardware to marry ourselves to their prognostications of the end of time.
During the postwar years of plenty, people stopped dreaming. We had bold dreams before WWII, but people stopped looking at how far we'd come and started comparing themselves to everyone else. We had no mortal enemy, tremendous wealth, and "keeping up with the Joneses" became the new operating protocol.
We have more than we did in the past. The manufacturing wealth of 1940-1970 was a fluke. The trade wealth of 1980-2020 was a fluke. We were upset over an unfair advantage that won't last forever. Even today we're still better off than a hundred years ago, yet everyone focuses on how bad things are.
Maybe a return to hardship will make us dream again.
It’s well understood that the expansion of the universe is not “due to general relativity”. General relativity does explain some details of that expansion.
The expansion of the universe is largely due to the impulse provided by the Big Bang. General Relativity does attempt to explain some details regarding what’s happened after the Big Bang, but provides no insight into the Big Bang itself. Nor does it offer insight into Dark Energy, a concept that Einstein opposed.
The universe is expanding due to general relativity... in the sense that Einstein literally wrote "... plus the expansion of the universe" into his equations.
I believe we already have the resources to colonise the Moon and maybe Mars right now. There would have to be considerable R&D, and willpower, and it would be very expensive but I think it is within our powers. Humans would have to live underground and deal with dust, maybe microbes in the case of Mars, but we could do it. The spaceships to go to Mars would have to be big but they could more easily be built on the Moon due to the lower gravity.
> I believe we already have the resources to colonise the Moon and maybe Mars right now.
That is or was essentially the mission of the US government's Artemis program, as I understand it. Some elements of the plan are (or were):
'Civilize' (my word) the Moon - build PNT, situational awareness, communication infrastructure, bases, permanent human presence etc. Bring it within a normalized region of operations, like Earth orbit (though obviously much more expensive and less utilized). A benefit is developing plans for infrastructure and operations on Mars, in a much more friendly and less expensive environment. What does it take to support humans efficiently and reliably on another body?
Also conduct experiments and develop technology for Mars in cislunar regions - again, much friendlier and less costly.
It's easy if you can build some kind of machine like what Eric Drexler talked about that could manufacture absolutely everything. Otherwise it's impossible.
The best hope for that is to send the one thing to Mars that people absolutely refuse to send to Mars which is bacteria and yeast and microbes. That could be a synthetic biology platform that could make pretty much all the molecules you need and then you assemble them with 3D printing or something like that.
We could send ten thousand workshop machines, a thousand huge forges and presses and reactors, and enough people to run them and all the farms and chemical vats they use those machines to build. Is that not enough manufacturing capability?
And that takes, what, a million of those "Starships?" To be plausible you have to be able to get it a lot smaller than that. If you can fit it into someone's hand the rocketry gets to be trivial.
Those big machines have lots of little parts and if you have to wait three years to get a spare part that’s a big problem. (Never mind anything that Earth sends to a Mars colony is a gift because it is inconceivable that it would be profitable to bring anything back)
Anyone who starts sketching out what a space manufacturing complex looks like (e.g. Drexler, myself [1]) comes to the same conclusion Drexler did —- there is this diverse residue of difficult to manufacture small but complex things. The good news is that we have molecular assemblers, they built you, and now that people are decoding the “junk DNA” we are getting a handle on genetic regulation networks and will be able to make them much more productive and reliable.
[1] unpublished study on manufacturing sunshades on an asteroid which is rich in something which is more-or-less “coal”, out of a lack of imagination I assumed it was going to use a pyrolysis system like https://www.netl.doe.gov/research/Coal/energy-systems/gasifi... and I can tell you that sort of thing on Earth has almost as many things that can go wrong with it as a fast reactor
You use your pile of lathes and mills to make replacement little parts. Probably skip making integrated circuits on-planet at first, but anything metal or plastic can be done by the huge group of machinists.
And for every fifty people on mars you can have a thousand people back on earth figuring out the best way to make every component.
The hard part is building chemical stocks of all these different things. And while that's a huge task, it's so much less hard than a make-anything machine. Once you have graphite, clay, rubber, and wood, making it into a pencil is simple. Cut, mix, extrude, clamp. Wood (and rubber if that's the easiest way) can be grown on-site, wood can be turned into graphite, and clay shouldn't be amazingly hard to get from martian soil. Oh and glue, we can figure out a glue.
You don’t need to go faster than light. Once you approach anywhere near the speed of light, time slows down so much that journey time becomes irrelevant.
Interstellar space contains neutral hydrogen atoms. Hitting a spaceship, they would produce electromagnetic radiation. When the collision speed goes past about 0.25c, the radiation becomes hard gamma rays which are dangerous to living things, and cannot be efficiently shielded against.
At this speed, the time dilation is slightly above 3%, so you're still not going to reach even Alpha Centauri in one human lifetime, or maybe you barely can.
Right, we are never leaving. We should get comfortable here, and take better care of the only habitable planet, rather than doing insane things and justifying that as "Don't worry, we'll make Mars habitable" and other silliness.
Well, things like the eventual expansion of our own star or the probability of a sizeable asteroid/comet hitting earth tells me, that we should at least keep thinking about leaving. Even if the current tech is nowhere near good enough.
Even if we do leave, it's unlikely that we do so for a very long time so taking care of the planet makes sense even if you intend to discard our crib. Similarly in the nearer term if we had a unified goal to colonize a near planet/moon that's still going to take a huge long term effort to do more than the equivalent of putting a tent up on an island off the coast to get that colony established (if it can ever be self-sufficient).
I think you should assume that the radiation hardened, self healing computer would consider itself alive.
But importantly that's not us leaving. Some distant future descendent of humans could have engineered itself to leave, but it's not us and we shouldn't fixate on that distant and unknowable future.
> Also, we've realized the scientific reality that traveling faster than light is likely impossible
I'm confused at what speculative fiction exists from before the 1910s (or thereabouts) which involves FTL? I've no doubt there's a handful of works but this is hardly a plausible explanation for a _recent_ decline in these topics.
> I'm confused at what speculative fiction exists from before the 1910s (or thereabouts) which involves FTL?
I bet very little. We didn’t really know how enormous the universe is (https://en.wikipedia.org/wiki/Stellar_parallax: “Being very difficult to measure, only about 60 stellar parallaxes had been obtained by the end of the 19th century”), and we hadn’t known for long that the speed of light is an absolute speed limit.
The weird thing about this is that interstellar space ought to actually be very hospitable to cold, highly efficient computational substrates. (This is for standard thermodynamic reasons: reliable computation must be free of noise, and low-temperature means low noise.) So there might be 'life' of a sort in interstellar space that's extremely smart and naturally long-lived compared to humans or even ordinary room-temperature AIs, but just can't do all that much in the outside world (i.e. has very low agency), except very slowly and with exceptional effort.
(Of course, these same constraints apply in a relative sense to the outer regions of planetary systems.)
We won't be crossing interstellar distances to look for habitable planets — we'll do it to mine material to build more of our own habitats, to spread further. We don't need to find planets to live on.
Acceleration at 1g lets you get to another galaxy in a single human lifetime (although earth will have been swallowed by the sun by the time you arrive). Relativity is pretty counterintuitive.
And yet we still have a solar system, empty of life other than Earth, we can expand to. Why try to cross an ocean when everything we could want is across the river?
Two things baffle me:
1. The idea that Terran life is toxic and must not be allowed on other planets in the solar system.
2. The one person who is advancing our space faring abilities by leaps and bounds is routinely vilified and excoriated on HackerNews.
There are a lot of ethical issues surrounding Neuralink and how it would be used. It might be good for certain medical stuff but I can see how it can be abused.
Mean people already do these things. Other people are already trying to use AI to decode your brainwaves and thoughts. There's no evidence Neuralink is doing anything unethical.
Neuralink has various potentials. One of them is that it becomes obligatory or even mandatory... If you don't get it, you'll be accused of being a luddite. It will probably start as a medical tool and progress to there.
The problem is that you are giving away access to your mind, one of the last private spaces. That means your thoughts can be stolen (think AI scraping but worse), or advertising put in your dreams. Perhaps even used to reprogram your mind etc.
When I was using Zortech C++ in the ‘80s, I never imagined I’d be talking to the author nearly half a century later about his support for a fascist Nazi near-trillionaire.
> I wouldn't support Musk if he was a fascist nazi.
That's not how that works.
Musk is, by many definitions well across the line distinguishing the 'fascist nazi's' from the rest of us.
Normalization of deviance slowly shifts the window to the point where his behavior is excused. Some people think it is acceptable because of all of the (potential) good a person could do or has already done. That's roughly the equivalent of 'Hitler was a vegetarian, and liked animals, how bad could he be?'. But The country that spawned the movement (so I think they get to make the call) thinks he is. And Musk's support for the German AfD (which is a thin layer of veneer over a despicable group) speaks volumes, yes, let's 'Make Germany Great Again' ffs. Even the Neo Nazi's think he is a Nazi. Elon has made Twitter (sorry, 'X') into a safe haven for the alt-right and various hate groups.
If it quacks like a Nazi and moves like a Nazi it probably is a Nazi. Whether you support him or not changes nothing about Elon but it does say something about you that you continue to support him despite everything he has already undeniably done and I'm disappointed, to put it mildly.
I think we can agree that Musk is strongly motivated. He works insanely hard and takes huge personal risks with his fortune.
He says why he does it - over and over - to save humanity by spreading it out into space.
> desperate for approval and accolades. From anyone.
If true, it is rather common behavior, not deeply unwell. Politicians 100% fall into that category. So do movie stars. So does every Olympic athlete. So what.
If he wants to save humanity, he certainly doesn't show it. Most of what he's done in life so far has harmed or taken more lives than the vast majority of individuals in history. His actions in "DOGE" vis-a-vis USAID may put him on the very top of that list, in the long run.
> If true, it is rather common behavior.
Wanting approval is normal. Most people would not support nazis for approval.
I think if you materially support the nazis, you are a nazi, regardless of what might be your internal justification. This is a distinction without a difference.
I think the distinction is important in this case specifically because it shows us that he has no strong conviction towards doing so. He knows it's wrong and does it anyways, it's worse.
>Why try to cross an ocean when everything we could want is across the river?
That "river" is still vast and nothing we want is on the other side.
>1. The idea that Terran life is toxic and must not be allowed on other planets in the solar system.
It's less the idea that Terran life is toxic and more that we're still hoping to find some forms of primitive life elsewhere in the solar system, and don't want those efforts thwarted by cross-contamination. You decided the rest of the solar system is dead, not the scientific community.
>2. The one person who is advancing our space faring abilities by leaps and bounds is routinely vilified and excoriated on HackerNews.
If you really can't comprehend the reason why Elon Musk is villified by people then there's no point in trying to explain it to you.
Suffice to say that owning a rocket company doesn't absolve a person of their sins to everyone, even on Hacker News.
> You decided the rest of the solar system is dead, not the scientific community.
The odds are heavily stacked against other life existing, and get worse with every probe. Of course, nobody can prove there is no other life. And it's not very credible that Terran life will out-compete locally evolved life.
And the idea that preserving some slime mold on Pluto justifies us constraining ourselves to Earth is just sad.
> If you really can't comprehend the reason why Elon Musk is villified by people then there's no point in trying to explain it to you.
I once asked another Musk-hater on HN why? All he could come up with is Musk called a diver a pedo-boy. I pointed out that Musk only did that because the diver went on national TV and told Musk to shove his submarine up his backside.
If you've got a better reason, I'd love to hear it!
Notwithstanding the other myriad of reasons to not like Elon Musk (of which there are many)…
You’re equivocating a childish insult with insisting that a person is a pedophile and hiring a private investigator to prove so and then writing scathing emails to reporters because they refuse to repeat claims uncritically. This is an appalling failing of morality on your part.
I’m frankly not inclined to dive into why I, previously a big fan of Elon Musk, find him personally repugnant because I expect you to apply the same standards to everything he does. That doesn’t take away from SpaceX, but we shouldn’t overlook his failings just because rockets are cool.
He hired the private investigator before he was sued.
You left out the part where he claimed a person was a pedophile and when asked if it was just an insult basically said “no I really think he’s a pedophile”, and started stating made up bullshit about child brides as fact. He only backtracked when he was sued. That is NOT the same as just throwing insults.
"Mr. Musk made these statements based on reports he received from a private investigator he hired to investigate Mr. Unsworth in preparation for the litigation that Mr. Unsworth had already threatened. Unbeknownst to Mr. Musk, the investigator’s reports were fabricated, and the investigator himself turned out to be a convicted felon who had gone to prison for fraud."
"Mr. Musk’s tweet was the culmination of an argument between two people that was punctuated by insults—not a factual accusation of the crime of pedophilia. The firm also demonstrated that Mr. Unsworth had not suffered any injury."
This level of defense seems highly inappropriate when you consider that the the unimpressive billionaire doesn't stoop down to this level, has a functional moon lander, ISRU technology that can manufacture solar panels on the moon and a long term plan for getting rid of SLS while the more impressive billionaire is struggling to get to orbit.
Musk said in 2019 that Epstein was “obviously a creep” and claimed that Epstein “tried repeatedly to get me to visit his island. I declined.”
Hmm..
> “Do you have any parties planned? I’ve been working to the edge of sanity this year and so, once my kids head home after Christmas, I really want to hit the party scene in St Barts or elsewhere and let loose. The invitation is much appreciated, but a peaceful island experience is the opposite of what I’m looking for,”
Hmm..
> “Will be in the BVI/St Bart’s area over the holidays. Is there a good time to visit?”
Hmm..
> “What day/night will be the wildest party on your island?”
Hmm..
> The emails between the two moguls come years after Epstein was convicted in 2008 of soliciting prostitution from a minor in Florida.
1) There may well be other biospheres in the solar system. There is some indirect and inconclusive evidence of microbial life on Mars, and even in the Venusian atmosphere. This dates back to results from the Viking and Venera, as well as more recent research. Earth life could be destructive to native life in these places, and vice versa (since they would likely be extremophiles) resulting in invasive species.
2) Musk is putting a lot of money into these things but he is still heavily subsidised by US government money and facilities (a loophole in the Outer Space Treaty allows individuals and corporations to claim other planets but not countries.)
> There is some indirect and inconclusive evidence of microbial life on Mars, and even in the Venusian atmosphere. This dates back to results from the Viking and Venera, as well as more recent research.
Yes, I've been hearing that forever. Every probe shrinks the envelope on the possibility.
> Earth life could be destructive to native life in these places,
Better us than slime mold.
> and vice versa (since they would likely be extremophiles) resulting in invasive species.
Perhaps. If anyone was transporting things back from there, there'd be a long space voyage where any such toxicity to the astronauts would be pretty clear.
2. Musk is not getting subsidies. He does get government contracts, where he exchanges rockets for money. That is not a subsidy, like if I make boxes and sell them to the government I am not getting a subsidy.
2. How do you define loans, tax credits and other subsidies then? You claim it’s this person specifically advancing space faring capabilities- which literally would not be possible without the US government. So please elaborate, as you’re not making sense.
There are possibilities of invasive species either way. Think of how Australia etc have struggled with various plants and animals that have taken over. We may find that some Earth life likes Mars too much and becomes an uncontrollable pest there (after some mutation), or that some microbe etc from Mars finds the Earth environment more hospitable and starts being invasive here. (Already predicted by HG Wells' "Red Weed".) That would not be unlikely as if Mars used to be more habitable then there could be life hibernating or waiting for a break, and Earth might offer it all the things it needs to reproduce quickly...
It's valuable for sure. It's nothing like, "The one person who is advancing our space faring abilities by leaps and bounds". There are many others, and many are doing more (again, NASA, etc.). JPL's homepage says "Our missions have flown to every planet and the Sun ...", and that they've been on Mars for four years, so let's be serious and not throw wild absurd claims at the wall (very Musk-like, though!).
Now that Musk led the way, sure. People laughed at Musk when he started out.
> NASA
Has sent a handful of probes out, only a handful because they are so costly. Now NASA can send out legions of them. There was a previous discussion here about why only one JWST was made and launched, at a cost of $10B. We all hope and pray it doesn't break down. Now with Musk's rockets we can launch lots of them and make N times the discoveries!
(With cheap launches, we don't have to make single machines that must be super reliable. We can make cheap machines at fractions of the cost, and so what if a few of them fail.)
Lowering costs by an order of magnitude changes everything.
NASA's work has been reduced to a "handful"? What is the point of writing that? And there is far more to cost of missions and their hardware than launching them. How much of JWST's cost was the launch?
NASA has launched about 200 probes since the 1950s. That's maybe 3 probes a year.
> What is the point of writing that?
Building one-offs is extremely expensive, meaning few will be built.
> And there is far more to cost of missions and their hardware than launching them. How much of JWST's cost was the launch?
Cost goes down dramatically when you build a twin. Maybe even by 90%. And then you get twice the science done! After all, twin Voyagers were made and launched, and twice the science indeed happened. Makes you wonder what we'd have learned if the twins had more siblings!
For contrast, 9600 Starlink satellites have been launched.
There were cars before the Model T, but only for the rich. Ford made cars affordable for everyman. That changed everything.
There were books before Gutenberg, but only for the rich. His printing press made them cheap enough to print newspapers. That changed everything.
Before Bessemer, making steel was extremely expensive and rarely one. With the Bessemer Process, vast quantities of steel could be cheaply made. That changed everything. Google says:
"The process revolutionized the industry by reducing costs and increasing production, making steel accessible for major infrastructure projects in the 19th and early 20th centuries."
I think we can agree that the current cost of going to Mars is currently unaffordable. The first step is to reduce the cost of launch, and that's proceeding well.
Interstellar space is also hostile to life, and any life present at the destination will not use the same DNA coding for protein (if gene expression even works that way).
We also do not yet have the technology for a complete survey of nearby habitable planets.
It is not an encouraging line of thought.