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What no one has seen before: gravitational waveforms from warp drive collapse

arxiv.org

81–90 of 118 posts

Re: What no one has seen before: gravitational waveforms from warp drive collapse

#81

Earlier quoted context omitted.

EDIT: the CALCULATIONS are right, but they're based on an incorrect assumption. As a poster further down this thread corrects me, while the energy of a GW obeys inverse-square, the amplitude is just inverse. I can't edit my original post, but the corrected calc is here. There is also a typo in my post where there's 10^-7 instead of 10^-5, but the calculations are done correctly. That corrected assumption gives: d_aud…

Sorry I hyperfocused on the value but it's really the context which makes it confusing: > 10^-7, that is, 4 times 10^-17 times larger than the gravitational wave detected which doesn't sound right. (Like saying "X is 0.1 times larger than Y" when X = 10Y.) The ear displacement is 2.5×10^16 larger than the gravitational wave, no? (Also I think 10^-7 should be 10^-5 in the quoted phrase, as per your reply above.)

> (Also I think 10^-7 should be 10^-5 in the quoted phrase, as per your reply above.)

Yeah, you're right, I had a typo in one of the intermediate numbers (the rest of the calcs used the correct number). Turns out I was just wrong overall though, not because of a typo but because of an incorrect assumption. Energy goes as 1/r^2, but amplitude is only 1/r, so the correct value is much smaller (it's about the Earth-Moon distance).

> 10^-7, that is, 4 times 10^-17 times larger than the gravitational wave detected which doesn't sound right. (Like saying "X is 0.1 times larger than Y" when X = 10Y.) The ear displacement is 2.5×10^16 larger

A is 2.5x10^16 larger than B is equivalent to B is 4x10^-17 larger than A, although I get what you mean by the phrasing being weird. "times the size of" would've been better than "larger".

Re: What no one has seen before: gravitational waveforms from warp drive collapse

#82
post #66
post #57

Earlier quoted context omitted.

It was closed as a duplicate because you asked 3 separate questions in your post, and the most prominent one (the title) was a clear duplicate of the original. I doubt it would have been closed if you had asked only "how powerful would the waves have to be?"

It's the same cognitive disconnect that comes up with Wikipedia and Debian too. People often add more facts to Wikipedia and complain when they get deleted. The misconception is that wikipedia is where facts go, whereas, Wikipedia is specifically trying to be a tertiary source, where all the facts can be traced back to primary sources and all the analysis can be traced back to secondary sources. People often complain…

> ...produces the high quality that made them all popular in the first place

Agree with everything you said in general, but you lost me at the very end in the context of this thread. Hard to equate Stack Exchange as a "high quality" destination. It was probably true in the first few years after inception, but years of tug war between "the business they think they're in" vs. "the business their users think they are" have made a terrible experience for said less-informed users.

When given an alternative (e.g. LLMs, ironically probably trained on their own content, but without the snarkiness and self-righteousness of their mods), users seem to be voting with their clicks [1].

[1] https://meta.stackexchange.com/questions/387278/has-stack-ex...

Re: What no one has seen before: gravitational waveforms from warp drive collapse

#83
post #28

Huh, 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 situa…

One of the reasons I no longer ask questions on Physics stack exchange: 1. I asked "how powerful" such waves would have to be to be audible. 2. I directly linked to another question whose accepted answer said "these waves can wiggle your ear drum" 3. Got my question closed as a duplicate but the link was to different question that only asked "is it possible" (and accepted the answer "yes") without there being any ans…

>I no longer ask questions on Physics stack exchange:

Lately, on the science fiction stack exchange, they've been opening new questions that are duplicates, then closing my old questions/answers as the duplicate, so they can point farm their own newer ones that naturally get more traffic while making sure mine are dead and can't get more upvotes. When you check dates, mine are all timestamped years before theirs.

I do remember the day Stack Exchange was announced (on reddit maybe), and I thought to myself how great it would be compared to Expert Sexchange... little did I know.

Re: What no one has seen before: gravitational waveforms from warp drive collapse

#84
post #76
post #31

Earlier quoted context omitted.

It can move soft tissues relatively to the skull bone, resulting in changes of pressure detectable by eardrums.

But 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?

When 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.

Re: What no one has seen before: gravitational waveforms from warp drive collapse

#85

Earlier quoted context omitted.

Primitive. (Primitive radios used a crystal for tuning. We have since gotten a lot better at tuning radios...)

To 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.

But we do use crystals for generating a stable frequency reference, which is then used in tuning.

Re: What no one has seen before: gravitational waveforms from warp drive collapse

#86
post #66
post #57

Earlier quoted context omitted.

It was closed as a duplicate because you asked 3 separate questions in your post, and the most prominent one (the title) was a clear duplicate of the original. I doubt it would have been closed if you had asked only "how powerful would the waves have to be?"

It's the same cognitive disconnect that comes up with Wikipedia and Debian too. People often add more facts to Wikipedia and complain when they get deleted. The misconception is that wikipedia is where facts go, whereas, Wikipedia is specifically trying to be a tertiary source, where all the facts can be traced back to primary sources and all the analysis can be traced back to secondary sources. People often complain…

> but their (sometimes inconvenient) organizational goals are what produces the high quality that made them all popular in the first place.

Plainly not true for either Wikipedia or Stack Exchange. The rules came later, once the rules lawyers showed up to help everyone understand that those sites needed to change because they were too useful for people. This might be ancient history, but the debates that raged on for the Wikipedia editors are important. There were people who thought Wikipedia should be what we all think it should be, and they'd been there since the beginning... but they were more interested in adding missing content to Wikipedia. The exclusionists though, who to a much lesser degree hadn't been there since the beginning, thought it more important to be more prestigious than Britannica, a paper encyclopedia, for their own egos or something. And they formulated rules that they believed would get them there. And more or less the same thing with SE, though it's a private business and less a open source project than Wikipedia. Every once in awhile you'll find a 15 or 20 year old question/answer, and you'll be gobsmacked by how just "nice" it was. There was room to go off topic a little, room to provide solutions rather than answers, and so on. Though, many of those are getting deleted now days. Wouldn't want the replicants to get any ideas about how SE is supposed to work.

The disconnect is that when the core group of users was much smaller, those places acted to some extent like a real world community of people, even if no one knew anyone and no one recognized anyone else's face. Because they were a community, people wanted to be helpful. If someone had a question that was difficult to find the correct wording for, others were willing to interpret and answer the interpretation. They really wanted to be helpful. But now the group of users is much too large, and instead of wanting to be helpful, they want to compete. No one can rack up 400,000 reputation being helpful. They can't rack that up if others are being helpful. And it doesn't feel like a community, so they don't ever feel like they should be helpful.

Re: What no one has seen before: gravitational waveforms from warp drive collapse

#88
post #40

Earlier quoted context omitted.

I 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…

Another 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…

Well 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.

Re: What no one has seen before: gravitational waveforms from warp drive collapse

#89
post #18

Earlier quoted context omitted.

I imagine the sound of the hull + everything else shuddering would probably dominate the perceived sound from eardrums or direct excitation of the air.

The hull is in a vacuum, and so are the eardrums.

If we are talking about manned spacecraft, I would expect the interior of the hull to be held at 1 atm.

Re: What no one has seen before: gravitational waveforms from warp drive collapse

#90

> Our work highlights the importance of exploring strange new spacetimes, to (boldly) simulate what no one has seen before. cute

The acknowledgements are also cool:

> The crew thanks the creators and actors of the Star Trek universe for their inspiration for this work.

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