Wikipedia:Reference desk/Archives/Science/2022 January 20

= January 20 =

Weather machine
Did anyone ever actually attempt to create a device for the purposes of manipulating the weather? Once read something about how the US military looked into how the butterfly effect could be weaponized to cause weather in Russia that would lead to droughts, floods, tornadoes, etc. - some facilty in Alaska? Also that the Russians were trying to do it too, but that it didn't work and so everyone gave up on it. Probably a conspiracy theory (I enjoy reading those sometimes), but just curious. 146.200.129.104 (talk) 11:55, 20 January 2022 (UTC)
 * See weather modification to see various efforts to manipulate the weather, to varying levels of success. Wikipedia has an article on everything.  -- Jayron 32 13:18, 20 January 2022 (UTC)
 * For a conspiracy theory, see HAARP. 2603:6081:1C00:1187:25B6:3B5:BCF7:4392 (talk) 14:55, 20 January 2022 (UTC)
 * The butterfly effect is that a butterfly wing flap on the other side of the world could literally be the difference between a hurricane or no hurricane years from now, there's no possible way humans could predict that. How do you have a years-long 24/7 video of the movements of a cow who isn't even born yet? Much less the entire world, even in caves? Sagittarian Milky Way (talk) 16:36, 20 January 2022 (UTC)
 * Except that the so called "butterfly effect" is not literally that a butterfly flaps its wing and it could mean the difference between a hurricane or no hurricane years from know. It is an analogy to explain how small changes in initial conditions can have large effects on outcomes of models. As stated in our article: "Of course the existence of an unknown butterfly flapping its wings has no direct bearing on weather forecasts, since it will take far too long for such a small perturbation to grow to a significant size, and we have many more immediate uncertainties to worry about. So the direct impact of this phenomenon on weather prediction is often somewhat wrong." A large initial perturbation CAN have a measurable impact, and one that is far easier to predict than a small perturbation.. --OuroborosCobra (talk) 18:35, 20 January 2022 (UTC)
 * The fact that I said you'd have to account for the cows and the caves and everything else in the world 24/7 shows that I knew the butterfly was just an example. Is a large initial disturbance (like nuking a hurricane I guess or maybe cloud seeding) really what scientists mean when they say the butterfly effect? I never said such tiny air disturbances could be accounted for in weather forecasts, in fact I said it could never be. No one could possibly make a model of the atmosphere that accurate. And since the minimum air disturbance size that materially affects the weighted random number generator that is weather shrinks with longer time horizons there definitely should be a time that's far enough in the future that every tiny animal movement now will change all the weather after then (without materially changing the climate probabilities, i.e. a dinosaur or Cro-Magnon couldn't have materially changed the percent of the 2nd millennium at 52°N 0°E 1km above sea level that was rain). Sagittarian Milky Way (talk) 19:24, 20 January 2022 (UTC)

Power source for Jupiter's aurorae
Does their energy ultimately come from Jupiter's rotational energy or from its internal heat (via convective dynamos)? I've been looking for papers but none explicitly analyzes these questions. JoJo Eumerus mobile (main talk) 20:44, 20 January 2022 (UTC)


 * The mechanism for the Jovian aurorae is basically the same as for the terrestrial aurorae: ionization and excitation of atmospheric gases by charged particles affected by disturbances with the planet's magnetosphere. The source of these particles on Earth is primarily the solar wind; from the JADE results it is known that there is an important other source in play on Jupiter. The magnetic field forming the magnetosphere is thought to be generated by what is called an "interior dynamo", but the mechanism is poorly understood. Here are links to scholarly articles on dynamo models for Jupiter. --Lambiam 21:18, 20 January 2022 (UTC)


 * Agreed: These dancing lights are produced when energetic particles from the sun or other celestial bodies slam into a planet's magnetosphere — the area controlled by a world's magnetic field — and flow down its magnetic field lines to collide with molecules in its atmosphere. Jupiter's magnetic field is extremely strong — about 20,000 times more powerful than Earth's — and therefore its magnetosphere is extremely large. If that alien magnetosphere were visible in the night sky, it would cover a region several times the size of our moon. As such, Jupiter's auroras are much more powerful than Earth's, releasing hundreds of gigawatts — enough to briefly power all of human civilization.   Alansplodge (talk) 21:29, 20 January 2022 (UTC)
 * Their energy mainly comes from the Jupiter's rotation. See magnetosphere of Jupiter. Ruslik_ Zero 20:23, 21 January 2022 (UTC)

Thanks. JoJo Eumerus mobile (main talk) 20:52, 21 January 2022 (UTC)

Can there be an immediate way to broadcast sound in the universe? "Bypassing relativity"?
I understand that the stars we see are actually light from stars that existed in the past (billions/trillions of years ago) and may no longer exist today, so the light is still "doing it's way" to us (even though it travels in a blazing speed).

Is there really no way to broadcast signals (light/sound) without this "slowness"? For example, is there no way for humans, at least in theory, to broadcast sound signals to other galaxies in some **immediate media**, bypassing the common situation of fast-but-slow *light speed travel*? — Preceding unsigned comment added by 79.176.222.75 (talk) 23:04, 20 January 2022 (UTC)


 * Maybe via tachyons, if they exist? (Otherwise, you'd have to get some unobtainium to build a transmitter, although it is rumored that gossip travels much faster than the speed of light.) Clarityfiend (talk) 23:37, 20 January 2022 (UTC)


 * Quoting our article Faster-than-light, oddly named, but whose topic is, specifically, faster-than-light communication:
 * Particles whose speed exceeds that of light (tachyons) have been hypothesized, but their existence would violate causality, and the consensus of physicists is that they do not exist, and their existence would imply time travel.
 * Actually, the mere assumption of the possibility of faster-than-light communication in a universe satisfying basic special relativity, regardless of the communication medium (waves, particles, telepathy, morphogenetic fields, Infinite Improbability Drive), already clashes with causality. If event S (send info) precedes event R (receive info) in some observer's frame of reference, and their separation implies FLT communication, the interval between the two events is spacelike in the Minkowski metric. This implies there is another frame of reference in which, for its observers, R precedes S: the message is received before it was sent. --Lambiam 01:00, 21 January 2022 (UTC)
 * That by itself is not necessarily a problem; that time is just a coordinate value you assign to the event, and it's OK in and of itself if the number is smaller. What's really a problem is if you can get a causal loop, which you can, if the faster-than-light communication conforms with relativity.  We have an article: tachyonic antitelephone.
 * Note that there is an assumption here. What if relativity doesn't work for tachyons?  Maybe there is a preferred frame of reference, but you can't tell if you just look at photons and bradyons, which is all we've ever observed.  This would fit with a neo-Lorentzian interpretation of special relativity, generally disfavored in the current day, but on metaphysical rather than empirical grounds. --Trovatore (talk) 01:20, 21 January 2022 (UTC)
 * This reminds me of TV ads where (unlike real life) the Twin Towers roof had a microphone and giant speakers and the bald guy would say "the New York Lottery jackpot is now (number).. MILLION.. DOLLARS!" and people are shown confused by the booming sky voice's existence at ever increasing distances and very exaggerated volume dropoff slowness finally ending with it still being loud enough to understand over the roar of Niagara Falls (hundreds of miles away). I always wondered if each TV market got a local version. Sagittarian Milky Way (talk) 01:13, 21 January 2022 (UTC)
 * Monarchy --Verbarson talkedits 16:21, 22 January 2022 (UTC)
 * Abdication emits an intense burst of kingon radiation that irradiates the entire universe simultaneously. Thus it can be used as an interplanetary distress signal. Everyone would suddenly be like "holy crap, the young king isn't king anymore, send space marines!". Sagittarian Milky Way (talk) 19:30, 22 January 2022 (UTC)


 * The article Faster than light leads to another article called Faster-than-light communication, which in turn includes a reference to Star Trek and its postulated Subspace communication. --←Baseball Bugs What's up, Doc? carrots→ 04:33, 23 January 2022 (UTC)