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What no one has seen before: gravitational waveforms from warp drive collapse
- gorkish 2y agoFunny that the sci-fi got it backwards. It seems rather obvious in hindsight that should it even be possible, we will clearly be able to detect warp signatures far before we would be able to build a machine capable of producing them.
- sparky_ 2y agoTrue, although the Fermi Paradox still sort of applies here, e.g., even if the galaxy were teeming with aliens zipping all over the galaxy in their warp-capable spacecraft, the odds of them charting a course right past our fairly uninteresting solar system seem low. This is likely not helped by the fact that we are more than halfway out to the edge of the galaxy, in one of the Milky Way's spiral arms; since we're not near the galactic centre, there are less possible travel paths that pass by us (if we just assume arbitrary random travel between any two points.) So even if it is happening right now in abundance, and even if we can detect its occurrence, are any of those paths close enough to us to be detected?
- JumpCrisscross 2y ago> we will clearly be able to detect warp signatures far before we would be able to build a machine capable of producing them We’re in the crystal-radio stage of gravitometrics.
- nico 2y agoExcuse my ignorance about the term, what does “crystal-radio stage of gravitometrics” mean in this context?
- AnimalMuppet 2y agoPrimitive. (Primitive radios used a crystal for tuning. We have since gotten a lot better at tuning radios...)
- ElevenLathe 2y agoTo be pedantic, the crystal is the rectifier in a crystal radio. Tuning was (or is, since there are still people out there playing with these things) still usually done via a normal tuned LC circuit. But yeah, we've gotten a lot better at rectifying too.
- marshray 2y agoBut we do use crystals for generating a stable frequency reference, which is then used in tuning.
- deleted 2y ago[deleted]
- ElevenLathe 2y agoThat's not what is meant by "crystal radio".
- marshray 2y agoYes, absolutely. I was referring to the part about "still usually done via a normal tuned LC circuit". Sorry for any confusion.
- rini17 2y agoNot even that, spark gaps and coherers :) And we can't really detect radio signatures yet, not farther than closest stars. Perhaps when we get solar gravitational lens telescopes.
- kelseyfrog 2y agoExcept now the dark forest hypothesis precludes the development and use of warp drives with detectable collapse signatures.
- kragen 2y agoso if we detect them we know it's false; that's very significant
- kelseyfrog 2y agoIt would be, but we still have to keep in mind that P(ETs|warp signatures) != P(warp signatures|ETs) and there's also the issue of the Schelling point of never being the first.
- kragen 2y agoagreed
- joe_the_user 2y agoI don't think warp drives would be different from other kinds of waves expanding in space - their strength would normally decrease at least the square of the distance simply because their energy wouldn't have a direction. And if the energy did have a direction, the odds of it being aimed at earth would be small. For that reason, only warp drive harnessing star-equivalent energy levels would be visible at distance of stars and so-on. I mean, Fermi's observation comes down to "there's no intelligent-being signature at the star-levels of energy we can see". But that could be because: intelligent beings are rare or because harnessing star-levels of energy is hard or impossible no matter how advanced a society gets or advanced societies have no need for such harnessing or because advanced societies follow the paranoid "dark forest" logic.
- dheera 2y agoAnother theory I have is that truly sufficiently advanced societies stop giving a shit. They figured out how to be in equilibrium with their resources and are capable of being happy that way. Giving shits about things is one of the big reasons we have wars and other potentially civilization-ending possibilities. Even if we are able to put 100 humans on a spacecraft for 100 years hurtling across the galaxy I'm pretty sure they'll start fighting among each other after 2 years. It's one of the reasons that I think we'll need to make embodied AGIs that are less prone to fighting to continue the legacy of civilization long term.
- seer 2y agoWell if a planet has a few intelligent species, the expansionist one would dominate the rest. If there is no expansionist species, after a time one will emerge due to mutation over time. Look at humans - there were a bunch of other intelligent species around the time humans came to the scene - we out expanded and outcompeted all them. Now of course this is just a sample of 1. But also seems kind of inevitable. So if mutation and natural selection are the only way for an intelligent life to emerge, it would probably also be expansionist, just by virtue of outcompeting everything else. And thus would naturally want to “explore” for the sake of it - just like humans. Of course there might be other ways to achieve intelligence- like it being developed by other species (AI). But same rule still apply. If there are more than one, eventually the one that wants to expand will expand more than the others that don’t… And even if the species found a way to “change themselves” to make them not give a fuck, by a virtue of change being possible eventually you’ll get expansionist “strain” again.
- spartanatreyu 2y ago> Funny that the sci-fi got it backwards. Sci-fi got it both ways. Even in the eponymous "warp drive" sci-fi: Star Trek, The Federation's Prime Directive states that uncontacted civilisations are not to be contacted until they are capable of initiating contact themselves. Usually this is by that civilisation achieving warp drive capabilities (which would allow that species to meet other species) but it can also happen with a species achieving subspace (faster-than-light) communications (which would allow that species to overhear or talk with other species).
- jiveturkey 2y ago> Our work highlights the importance of exploring strange new spacetimes, to (boldly) simulate what no one has seen before. cute
- SoftTalker 2y agoIt's fun that people can get paid to do this.
- dylan604 2y agoWhy not? People get paid to play video games and any other vast number of examples that break the traditional concept of "job"
- SoftTalker 2y agoI was being genuine. It would be great to have that kind of a job.
- fghorow 2y agoI Dinnae Hae Lang The Engines Can Take It, Cap'n! </Scotty>
- pezezin 2y agoThe acknowledgements are also cool: > The crew thanks the creators and actors of the Star Trek universe for their inspiration for this work.
- wrycoder 2y agoWhat no one had modeled before.
- largbae 2y agoThis is excellent. Like the Dyson sphere, predicting signals for technologies that we can imagine but not yet construct seems like a great way to guide our search for other life. Now we need a team of smart folks to identify tearing or other processing anomalies in universe-scale simulations.
- ganzuul 2y agoIf you like spooky stuff there is lots of fun things to think about. Just off the cuff; We are predicting a soul upload technology with Neuralink etc. So an alien technosignature could look like: https://en.wikipedia.org/wiki/21_grams_experiment https://en.wikipedia.org/wiki/21_grams_experiment This one is not rigorous but there are lots of other possibilities of this pattern.
- cydodon 2y agoIf measurement of the soul's weight gave 21, that can only be half of the answer[0], right? [0] https://en.m.wikipedia.org/wiki/Phrases_from_The_Hitchhiker%27s_Guide_to_the_Galaxy#The_Answer_to_the_Ultimate_Question_of_Life,_the_Universe,_and_Everything_is_42 https://en.m.wikipedia.org/wiki/Phrases_from_The_Hitchhiker%...
- trystero 2y ago2 souls united, that's the meaning of life.
- x3n0ph3n3 2y agoThat experiment was so poorly performed that it can be completely discounted.
- causality0 2y agoAt absolute best, it would be soul copying, not uploading.
- bluGill 2y agoAdvanced life. There is no particular reason to think there is life out there (if there is or not - both are extraordinary). If there is, there is no particular reason it is advanced - vs just some plants and animals living a life but not doing anything different from the first members of the species. (that is not advancing to where they might get a house)
- perihelions 2y agoHuh, so you can hear things explode in space, after all. If you're close enough to a warp field doing funny things, the gravitational wave strain would create audible-frequency artifacts, as it wiggles your eardrums at frequencies close enough to the audible. They derive an equation for estimated strain as a function of distance from the warp bubble collapse. How does strain translate to sound intensity, in the situation where a gravitational wave is driving sound pressure waves, and/or directly wiggling eardrums?
- WJW 2y agoWould it even wiggle the eardrums relatively to the rest of your head? Intuitively it seems that would only happen if the wavelength is exactly right, but at that wavelength the frequency would be inaudible because the speed of light is so high.
- deleted 2y ago[deleted]
- rini17 2y agoIt can move soft tissues relatively to the skull bone, resulting in changes of pressure detectable by eardrums.
- amelius 2y agoSo those whooshing sounds of spaceships in sci-fi movies/series were real after all ...
- paulb73 2y agoBut surely it isn't wiggling the tissues by sound waves passing through matter, but by vibrating space time itself? The skull shouldn't be able to resist gravity waves any more than soft tissues or 10km of lead?
- dotnet00 2y agoWhen a gwave passes through, since the space contracts or expands, you get changes in density, since bone and soft tissue are different densities, there should still be a pressure differential that can be heard.
- wizardforhire 2y agoStill waiting for the complete lack of gravitational waves as result of Omega particles
- Optimal_Persona 2y agoGood thing it runs on negative energy - there's no shortage of bad vibes in the world today!
- danyala 2y ago> The signal comes as a burst, initially having no gravitational wave content, followed by an oscillatory period with a characteristic frequency of order 1/[R] Interesting... > As discussed above, for a 1km-sized ship, the frequency of the signal is much higher than the range probed by existing detectors, and so current observations cannot constrain the occurrence of such events And yet, you still chose the word ;) So, how big are the ships, as a kindness for readers such as myself for whom the exercise should not be left? https://www.ligo.org/science/GW-Burst.php https://www.ligo.org/science/GW-Burst.php
- m463 2y agoIs this like imagining what jets would sound like and listening for that sound?
- DarmokJalad1701 2y agoAre there any good resources for someone to learn how to write some Numerical Relativity code?
- dsqrt 2y agoThe NRPy package and tutorials are a good place to start: https://nrpyplus.net/ https://nrpyplus.net/
- stevenalowe 2y ago"...to (boldly) simulate what no one has seen before."
- deleted 2y ago[deleted]
- mrlonglong 2y agoDoes that means if we can make our gravitational detectors sensitive enough we can detect warp drives passing through the universe?