7 ms·
I wonder if gravity wave detection could be ever be precise enough for communication. I wonder this because it occurs to me that one possible answer to Fermi's
by TomMckenny 8y ago
I wonder if gravity wave detection could be ever be precise enough for communication.
I wonder this because it occurs to me that one possible answer to Fermi's paradox is that aliens don't use Radio or other EM to chat.
And maybe they don't leak it because they move energy and information around more efficiently than we do.
- meowface 8y agoEven if tons of intelligent civilizations happened to be radiating gravitational waves (or some other form of radiation which travels at or very close to the speed of light) encoded with information directly towards Earth right now, it's very likely we'd never receive them in the next million years due to the vastness of the universe.
- roywiggins 8y agoWhat about all of the intelligent civilizations who were doing it a million years ago? With a million years for waves to fill space, you'd think we'd be able to hear something.
- LoSboccacc 8y agoNot necessarily, immagine scanning all radio frequencies except you don’t know neither modulation nor the symbols transmitted. Separating something from noise is a challenge on itself especially if signals are compressed or encrypted
- meowface 8y agoMaybe. Or maybe the time range of broadcasts that reached our solar system was several millions or even billions years ago. Or maybe it was as recent as 10,000 years ago, but we had no way of detecting or decoding them. Or maybe nearly all of the intelligent life existent in the universe doesn't yet have the capability to transmit information via gravitational waves or other resilient media. Or maybe humans really are one of the first instances of intelligent life in the universe, and the broadcasts won't start coming until millions of years from now... or never. And the most disappointing/intriguing part is there's a good chance humanity will never, ever know the answers and will never have any confirmation or denial of any of those possibilities. Or if they do, it might be so far into the future that humanity as a concept will cease to exist. The universe is just too big.
- maxxxxx 8y agoWhat would be the advantage of using gravity waves?
- lazysheepherd 8y agoI was about to comment to state that there is no advantage because both gravitational waves and electromagnetic radiation travel at the same speed: "c". But then it struck me, maybe there will be one advantage, EM can be absorbed, blocked and warped while gravitational waves are not affected by anything, thus guaranteed to deliver the message(?)
- the8472 8y agoYou could also use neutrinos for the same reasons and they have the advantage that it's a lot easier to emit them as a beam instead of omnidirectional waves.
- krapp 8y agoMaybe the complexity required in detecting them acts as a form of security by obscurity. It's far more likely that radio waves would be intercepted.
- MauranKilom 8y agoRadio waves were first predicted almost exactly 150 years before the first confirmed detection of gravity waves. Either signal takes millions to billions of years to travel across the universe.
- sleavey 8y agoOne reason would be that gravitational wave amplitude decays only as 1/distance instead of electromagnetic radiation which decays as 1/(distance squared). ...But man-made gravitational waves are, without some scientific advance eclipsing the discovery of electricity, completely beyond any human capability of being produced at the levels required for extra terrestrial communication.
- Faaak 8y agoYour idea is actually used in "the three body problem" trilogy. If you like that sort of sci-fi, read the book; it's worth it !
- josho 8y agoI’ve had similar thoughts and assume aliens would use something like lasers to have point to point communication rather than broadcast RF. Of course for us we’d never detect those point to point transmissions unless we were incredibly lucky to be along the vector between two aliens communicating.
- meowface 8y agoEven if you assume a "manycast" or "broadcast" type of communication rather than point-to-point, e.g. some kind of technology which could radiate information-packed gravitational waves traveling at light speed in all directions of 3D space simultaneously, and even if you assume hundreds of thousands of independent intelligent civilizations throughout the universe are doing this right now, it is likely humans will never, ever detect any of them, due to the sheer size of the universe.
- sillysaurus3 8y agoAnother answer to the Fermi paradox is that a Kardashev Type 4 civilization is able to harness the power of an entire universe. We wouldn't be able to detect this by definition, since they exist outside of our perceived reality. At first glance, this seems to be a useless theory, since it's not refutable. But it lends itself to a belief system: by studying the universe, we gain an understanding of whatever created it. This is helpful as a motive: a reason for studying any of this at all, in absence of economic or social incentives. This seems important. As the centuries tick by, and as we confirm and re-confirm that we are indeed alone and that we do indeed have a mostly-complete model of physics, there will become less and less incentive to analyze the corner cases. It's costly, and takes decades. But at one time, it was costly and took decades to build a cathedral. Yet we accomplished these impressive feats due to a shared belief system. The reason I brought this up is that we often like to believe there is an advanced alien civilization tucked away in some corner of some galaxy, sending out messages via gravitational waves or neutrinos. But why do humans find this idea so seductive? It's because of an underlying loneliness: we want to believe that we are connected with the universe in some fashion, that our existence has a point, and that there is reason to do anything at all in a universe that will exist long after we've gone, long after our solar system and sun has gone. Because if there were an alien civilization, at least we would not be so alone. In that context, a solution to Fermi's paradox is simply to believe that our very universe exists due to some higher-order phenomena not knowable within our reality. And by studying the laws of physics, we gain a glimpse into the boundary between our universe and its hypervisor.
- a1369209993 8y agoCommunication is a red herring; the actual Fermi paradox is why huge sections of the night sky aren't black[0] due to all the stars being enclosed by Dyson spheres. Or, for that matter, why the planet hasn't been eaten by von Neumann swarms yet. 0: technically a uniform dim infrared of waste heat
- nonbel 8y agoThis is called Olbers paradox, and is much older: https://en.wikipedia.org/wiki/Olbers%27_paradox https://en.wikipedia.org/wiki/Olbers%27_paradox
- a1369209993 8y agoThat's "Why are there any parts of the sky that aren't stars?". The Fermi paradox is "Why are there any parts of the night sky that are (unobstructed) stars?".
- perl4ever 8y agoI thought that huge sections of the night sky are empty - we call them Cosmic Voids. See: https://en.wikipedia.org/wiki/Void_(astronomy) https://en.wikipedia.org/wiki/Void_(astronomy)
- spacenick88 8y agoTo me Dyson spheres seem decidedly low tech. Why do we think a very advanced alien species would a) even need such an amount of power b) use such a primitve method as wrapping a star in solar panels? The only stuff I can imagine needing such energy levels would be wormhole gates or Alcubiere drives. Powering the former with a Dyson sphere might make sense but the latter would have to fit on a ship. The interstellar aliens I find more realistic would be those that just mastered cryo sleep or general AI and built seed ships. We don't really have any way of detecting those, do we?
- elorant 8y agoIf you want to communicate with an alien civilization you'd have to emit some kind of signal for a long period of time in order to ensure that they will receive it. Gravitational waves last for an instant and then you've missed them. Even if you've established communication with another civilization, using gravitational waves to carry on chatting seems like an awful waste of resources. The only scenario that seems plausible for using them is some kind of an SOS signal in which case you ensure that it will reach the vastness of the universe and hope that one of the receiving folks would be able to decode it. But then again that would take billion of years.
- eternauta3k 8y ago> Gravitational waves last for an instant and then you've missed them. Could you go into more detail? How do they differ from EM waves?
- ajkjk 8y agoI don't think the OP is right. The waves LIGO detected lasted for an instant because they were from a fleeting cosmic event - two black holes spiraling into each other. But there's no reason as far as I know that a much more sensitive detector couldn't see waves from more mundane, longer-lasting events. Though - at that point, why not just send EM waves? They travel the same speed. Maybe gravitational waves could penetrate anything, if you're willing to spend planetary amounts of energy to do it?
- elorant 8y agoI'm not a physicist so I can't elaborate much on the subject. From a few articles I've read at the time of the LIGO discovery they mentioned that the signals lasted for a very short period. Other than that I might be totally wrong so don't take for granted my assumption.
- basementcat 8y agoMuch of the data from LIGO is publicly available. Most scientists have been looking for chirp-like signals indicative of events like colliding black holes. Maybe you can find some other interesting signals? https://losc.ligo.org/s/events/GW170104/LOSC_Event_tutorial_GW170104.html https://losc.ligo.org/s/events/GW170104/LOSC_Event_tutorial_... Note that there's quite a bit of interference from the Earth. (trucks driving about, etc)