Alcubierre warp drives are cool, though keep in mind the difficulties with the idea as it is currently understood: https://en.wikipedia.org/wiki/Alcubierre_drive#Difficulties
In all this excitement hopefully we don’t forget the horde of luddites that’s the modern physics community that couldn’t imagine the possibility of faster than light travel. Like I get it, it’s absurd to consider FTL in regular space time, but when a normal person asks this question all they care about is whether they can realistically imagine going from one star to another in meaningful timespans. Pretty much every physicist I talked to online and offline would scoff and call the concept “absurd” (which is technically true in regular space time). I even believed them for a while. They’d shut down any discussion or imagination before it was even possible. Even now you see the same backwards thinking instead of being excited at least by the theoretical possibility.
Even last year when I brought up the Alcubierre drive to a physics PhD he wasn’t aware of it, and couldn’t imagine this being anything other than a joke (even after showing him the Wikipedia page).
Like a bunch of science fiction writers could think of something called “warp drive” and it took decades for some dude in Mexico to imagine a theoretical potential method to do this?
The last great physicist in my opinion is Carl Sagan, the entire field just like most sciences have rotten to the core into completely unimaginative folks who cannot fathom a world that’s only marginally different from what’s currently around them.
Richard Rhodes spends a lot of time in his “making of the atomic bomb” to figure out if the original inspiration for the atom bomb might have come from HG Wells. We’ve had great imagination in our science fiction, only our scientists have lost whatever mojo used to be there (and I suppose a gun to the head in the name of Nazism) to inspire from it.
Of course it would have the limitation that you could only send information back to a point after the "time machine" had been switched on, and you could only communicate to entities in the future who knew of your time machine's existence and design, but that's enough of a pinhole to send lottery numbers back through.
This has probably been considered before in fiction, where presumably the author thought about the other practical problems, like the time machine being on a rotating and Sun-orbiting Earth, meaning that the spatial distance between the time machine's location on subsequent days can be considerably large (relative to reference frame of the Sun). I don't know what the engineering consequences of that are.
It definitely steps around P=NP. You could try a large number of costly experiments and "send back" the working solution. The parallel experiments collapse into one.
You can send canary messages back to yourself to know if you're in danger, assuming it's you on the other side.
But perhaps the signals from the future are actually from an advanced adversary, such as an AI, and they're telling you to make moves that will lead to your demise (or the rise of the adversary).
The future adversary knows your actions and can send crafted messages to nudge you to the desired outcome. Perhaps similarly to the "P=NP" parallel explorations in the future from the past, the future has parallel simulations of your past behavior to optimize the future outcome.
It breaks the rules, but it'd be fun fiction.
"Thrice Upon a Time" by James P. Hogon, 1980. [1] It plays with interesting implications. In the book, sending a message to the past changed that version of the past.
My under standing is temporal communication in our universe is likely to be different. You couldn't change your past, so somehow things would line up no matter what you did.
But perhaps you could impact events you had not yet measured, since that impact, and your after-sending sampling of them, would leave a lot room for impact without contradicting any information you had at the time you sent.
For instance, you send a message back to your collegue to buy a stock yesterday, and you haven't seen him since last Tuesday. So nothing weird would have to happen to achieve consistency. Presumably your friend bought the stock, knew not to tell you until tomorrow to give you time to have sent that back to him. If the colleague tried to tell you earlier, something would stop him - because obviously he wasn't able to before you sent the message.
A good way for the colleague to risk their life since a serious accident would be the best way for time to prevent a determined colleague from changing the universe!
That means things in the time loop (from received time to sent time) could get very weird to achieve consistency.
I just don’t see how this works in the extremely simple case where you send the message to your past self. Using the colleague just tries to sidestep this. What physically happens if you attempt to send a message to yourself that you don’t remember receiving in your past? Does the system just consistently malfunction? Does it turn out that you had an accident between receiving and sending that caused memory loss?
It's not like you always, at any moment, remember every single moment of your life. You send it back, and then you remember it. You couldn't have remembered it before you've sent it back, but as soon as you did, you remember reading it.
Makes perfect sense to me. I see no reason why the memory wouldn't spontaneously form.
Oh come on now, that's obvious bullshit. The term "sound barrier" doesn't predate the 20th century and was only popularized during WWII. Any physicist claiming it was a fundamental limitation would've needed to be completely ignorant to the existence of artillery. Who were these supposed physicists and what specifically did they claim?
https://en.wikipedia.org/wiki/Prandtl–Glauert_singularity
> The Prandtl–Glauert singularity is a theoretical construct in flow physics, often incorrectly used to explain vapor cones in transonic flows. It is the prediction by the Prandtl–Glauert transformation that infinite pressures would be experienced by an aircraft as it approaches the speed of sound. Because it is invalid to apply the transformation at these speeds, the predicted singularity does not emerge.
> The incorrect association is related to the early-20th-century misconception of the impenetrability of the sound barrier.
I learnt about it from Destin's video: https://youtu.be/p1PgNbgWSyY?t=816
Likewise today, we know something is wrong with the combination {relativity, quantum mechanics} because if our formula for both were completely true, the universe wouldn’t exists.
The supersonic munitions of the era were rather difficult to ignore, so you need better evidence to claim PhDs would’ve laughed at the idea, than merely that the best formula they had at the time was not good enough.
This never happened. I have no idea how this myth entered the popular consciousness, but it's nonsense.
There was a superstition by pilots that going past the speed of sound was inherently dangerous because of many accidents when planes did go faster.
https://en.wikipedia.org/wiki/Prandtl–Glauert_singularity
> The Prandtl–Glauert singularity is a theoretical construct in flow physics, often incorrectly used to explain vapor cones in transonic flows. It is the prediction by the Prandtl–Glauert transformation that infinite pressures would be experienced by an aircraft as it approaches the speed of sound. Because it is invalid to apply the transformation at these speeds, the predicted singularity does not emerge.
> The incorrect association is related to the early-20th-century misconception of the impenetrability of the sound barrier.
I learnt about it from Destin's video: https://youtu.be/p1PgNbgWSyY?t=816
There's no reason academia and research labs should have a monopoly on such opportunities these days. All it really takes is burn time, dedication and intelligence.
Why don't some of us just spend our time on these kinds of things? Far as I can tell, the equipment expense is well within the budget of a co-op of well paid tech folks.
https://doi.org/10.1007%2Fs10701-011-9539-2 - cited 57 times
https://doi.org/10.1088/1361-6382/aafcea - cited 47 times
https://doi.org/10.1103/PhysRevD.56.2100 - cited 123 times
Each of these papers propose a separate method of faster-than-light travel. Where's the lack of imagination?
> Like I get it, it’s absurd to consider FTL in regular space time, but when a normal person asks this question all they care about is whether they can realistically imagine going from one star to another in meaningful timespans. Pretty much every physicist I talked to online and offline would scoff and call the concept “absurd” (which is technically true in regular space time). I even believed them for a while. They’d shut down any discussion or imagination before it was even possible. Even now you see the same backwards thinking instead of being excited at least by the theoretical possibility. Even last year when I brought up the Alcubierre drive to a physics PhD he wasn’t aware of it, and couldn’t imagine this being anything other than a joke (even after showing him the Wikipedia page).
What's the difference between "regular" and "non-regular" spacetime? Also, maybe the physicists you talked to worked in other subfields of physics and didn't have expertise in this topic? Imagine going up to a professor in computer networking and asking what they think about the P=NP problem.
> Like a bunch of science fiction writers could think of something called “warp drive” and it took decades for some dude in Mexico to imagine a theoretical potential method to do this?
A bunch of science fiction writers also thought up of something called "transporters" and we have no way of making it real. Another group came up with PADDs and we have them now. You're cherrypicking one data point and generalizing it.
> The last great physicist in my opinion is Carl Sagan, the entire field just like most sciences have rotten to the core into completely unimaginative folks who cannot fathom a world that’s only marginally different from what’s currently around them.
Roger Penrose is still alive, and has a Nobel Prize in physics. We also took a picture of a black hole two years ago. Isn't that a great scientific achievement as well? It seems as though you're mistaking Sagan's scientific outreach efforts for actual scholarship on the subject.
I suppose what I'm trying to say is that I see the opposite of what you do in academia. For me, it seems to be still working well. Sure, there's still weird politics and worrying about being scooped, but ideas that are credible won't be shot down, but anything that doesn't make sense would be ripped to shreds.
Carl Sagan was not just great at outreach but also doing good science. You can watch his cosmos show half a decade later and think wait what exactly have we discovered new since then and draw a blank. Taking a photo of the black hole is great but if that’s all you have as progress for All of humanity in 50 years then think for yourself.
penrose and Hawking are alright but I didn’t mention penrose thanks to him becoming a crackpot in recent times. Point is such folks are few and far. I’m not convinced we have gotten dumber, but it’s definitely true that we have been programmed into complacency in the imagination department.
Hhhmmmm...
Nonsense. Szilard thought chain reactions were possible and worked years to prove this is the case. The bomb was an immediate and obvious consequence.
Science fiction writers don't push physics or science forward. Physics and science push science fiction forward. As we discover more, what we can imagine also grows.
> Like a bunch of science fiction writers could think of something called “warp drive” and it took decades for some dude in Mexico to imagine a theoretical potential method to do this?
People 5,000 years go could imagine flying. But that doesn't help you with flying at all. Just because someone wrote a cute story about how nice it would be to fly, doesn't mean you're any closer to doing it.
The correct analogy is about how long you go from someone imagining a flying machine where the wings don’t move to an actual plane. They called it “warp drive” for heavens sake.
Also comparing the lack of progress today to the lack of progress in medieval times is not the flex you think it is.
No way. The idea that your wings don't have to move wasn't new, it's ancient. People were building paper planes thousands of years ago. If all it took to fly is to not move your wings, people would have been flying around thousands of years ago.
Making a flying machine takes far more than that. You need to understand the lift equation, how airfoils work, how and why you can and can't control wings and attitude, etc. The Wright brothers didn't strap wings to a bicycle, they spent years working on the physics and engineering of flight, including building wind tunnels.
From the outside, at a high level, without understanding the physics or engineering of these systems, it's easy to say "Oh, it's just X". Like looking at the solution to a chess problem and saying "Of course, I would have seen that". You wouldn't have. As evidenced by the fact that no one did. For millenia.
> Also comparing the lack of progress today to the lack of progress in medieval times is not the flex you think it is.
I never said there's a lack of progress today. Scientific progress is amazing today, far faster today than at any point in history.
What're you basing this on/how're you defining the growth rate here? Not rhetorical, would be interested to see your data since it seems quite a common argument to hold that it's slowing in lots of areas
One kind of metric to look at are published papers, patents filed, money invested into science, total citations. All of them are increasing a lot. But these are terrible and unconvincing, you could see the numbers go up if we were spinning our wheels.
The value of science and engineering should really be measured in terms of how much easier they make our lives. If you look at that, it's hard to find a metric that doesn't show that scientific progress is healthy and increasing. Moore's law is still going. The cost of solar per Watt is down like 100x in 30 years. The cost of batteries is down 50x in 30 years. The cost of sequencing a genome is down 10,000x in 20 years. Productivity per worker doubled in 30 years. 30 years ago digital cameras were super low resolution, now they're amazing. 20 years ago computer vision could barely detect a person walking in front of car, it was state of the art research; it's now so reliable the new infrastructure bill makes it mandatory for new cars.
I picked examples from all sorts of areas of the economy and human life for a reason: none of these are down to one discovery. They required countless advances from material science, to basic physics, even the mathematics, engineering, etc.
Everything is far cheaper to make today and people are far more productive compared to 30 years ago, and it's just incomparable compared to 60 years ago.
But I get it. It doesn't feel that way. That's not a science problem. That's a politics problem. The gains from all of these improvements at a societal level are mostly going to the ultra-rich sadly, because people vote against their own best interests routinely.
Digital cameras and batteries aren't in the same league as game changing concepts like quantum theory and relativity.
Game changers don't just mean you can make stuff cheaper, they mean you can imagine completely new kinds of stuff that were literally unthinkable before the game changed.
Before you can improve batteries you have to invent the concept of a battery. Which means having some basic understanding of electricity. Before you can improve computer vision you have to invent the concept of a computer. Which requires inventing a theory of computability.
And so on.
The point is there really hasn't been a lot happening at the game changer level for a long time now. Refinement is fine, but it's unwise to confuse it with fundamentals.
This pretty much gives away that you aren't a scientist. The vast majority of fundamental research opens up new ground in highly specialized areas. It slowly trickles out as improvements that you don't seem like "game changing concepts" but they required game changing concepts at a low level to get things done. That's scientific progress and that's the game changer.
> Game changers don't just mean you can make stuff cheaper, they mean you can imagine completely new kinds of stuff that were literally unthinkable before the game changed.
And I don't think you've ever dealt with transitioning science from the lab to industry. The game changer is the cost and availability. There are plenty of amazing things that don't matter in real life because they aren't practical. They aren't game changers.
> Before you can improve batteries you have to invent the concept of a battery. Which means having some basic understanding of electricity. Before you can improve computer vision you have to invent the concept of a computer. Which requires inventing a theory of computability.
You definitely don't need computability to invent a computer. And you've got the discovery of the battery exactly backward. First Volta made a battery by trying to replace frog parts with paper and brine. Then we could go back and understand electricity; that was Volta's real lasting contribution. Before we had batteries electricity wasn't understood at all.
> The point is there really hasn't been a lot happening at the game changer level for a long time now. Refinement is fine, but it's unwise to confuse it with fundamentals.
This is nonsense. Who are you to decide what is or isn't fundamental? Why are scientists and engineers supposed to bow to your aesthetic sense?
No. All that matters is results. And the result is, 3x productivity increase in 50 years. And all of those other things I showed you, hundreds of x improvements in all sorts of practical engineering areas that make daily life far better. What matters are all of the incremental gains because they enable technological revolutions.
I don't think anyone actually understands how they work.
More broadly, I don't buy for a second that science fiction doesn't feed back into the minds of scientists and engineers working on the next big thing. It would be strange if it didn't, and I think the burden of proof is on you to show that scientists and engineers are universally exercising the sort of perfect mental hygiene it would take to isolate themselves from the baseless speculations of writers.
You don't need to isolate yourself. The baseless speculations of writers just don't help in doing science. If you pick any discovery, you'll see that it was a consequence of a lot of work and intuition about a particular area of math, physics, engineering, or biology. Scientists aren't waiting for the next Star Trek episode hoping to find some ideas. The reason is simple: the ideas in science fiction don't work. Almost always what we get is totally different from what was predicted and usually more amazing, and it's shaped by the math/physics/engineering/biology that led us there, not b some outcome we want to match in science fiction. It's just a cognitive bias that you remember good SF predictions and forget bad ones.
This whole Wells atomic bomb business is a prime example. Szilard couldn't possibly get any ideas from Wells. Because Szilard's actual contribution has nothing to do with what Wells wrote. He discovered chain reactions. And how he did so is well documented, by analogy to chemical chain reactions. Literally nothing in Wells would ever help you discover nuclear chain reactions. Nor is it obvious that what Wells wrote requires chain reactions, you can think of other fanciful mechanisms.
I can't help but notice that you seem to have completely ignored it in the construction of your response. Perhaps you didn't read my comment very thoroughly.
Just because I do AI research and tell someone I watched Star Trek, does that mean I'm saying that my latest NeurIPS paper is inspired by Star Trek? No way.
You've overextended your argument, and you know it. There is no use continuing this conversation if you're going to go to such absurd lengths to deny what's obvious.
Like robots, flying cars, space stations, tablets, electric cars, AI...?
Sci-fi lets us set impossible looking goals, until somebody comes up with something similar and practical. I'd give sci-fi more credit for shaping our current world. Writers dream, science builds which I think is a beautiful symbiosis.
There's a kind of funny example of that involving Kip Thorne, or rather Kip Thorne's students. He ran into his friend Carl Sagan at some event--I think it was something like they arrived at the airport at the same time for some conference they were both attending and ended up sharing a cab [1].
At the time Sagan was writing his novel "Contact", needed FTL travel in it, and was hand waving away how that would be done. Sagan was aware the one of Thorne's pet peeves was science fiction that hand waved away things like that without at least trying to come up with something that might be plausible or at least wasn't known to be impossible.
Sagan carefully broached the subject of "Contact" and that he was hand waving FTL in it, and asked if Thorne could come up with some justification for Sagan's FTL. That set Thorne onto researching wormholes for travel and he found solutions that didn't appear to be definitely physically impossible. Thorne wrote a guide to wormhole travel for Sagan to use to make "Contact" less hand-wavy.
Thorne then put a problem on the final exam for Caltech's Ph 236, General Relativity, that set up the conditions for a pair of connected wormholes and asked the students to calculate what would happen.
Most students got that you would get a pair of connected wormholes, but Thorne was disappointed that none of the students had noticed that this seems to give a way for FTL travel.
[1] I'm going by memories of reading drafts of a book Thorne was working on 40 years ago so details are a little fuzzy. He was writing a book for the general public that was going to be about contemporary physicists. Each chapter was going to feature an interview by Thorne of a contemporary physicist and an explanation of their work. Thorne had his notes, interviews, and draft chapters on his account at the VAX of the Caltech High Energy Physics department, and it was world readable so was widely read by the other people with accounts on the machine. It's too bad it never came out. My recollection was it looked like it was going to be very interesting.