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Bonus bonus points: Creationists on facebook smugly thinking this is all prove of a divine hand.
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Dec 10, 2019 00:41
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Libluini posted:Except our math and physics could be all wrong, for all we know (which is not much). When your speculation rests on the laws of thermodynamics or relativity being wrong, weep for your speculation. The universe would have to be very, very different from what we perceive and experience, in remarkable ways. And nothing we have so far uncovered would continue to make sense. It's a sucker's bet.
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Dec 10, 2019 07:32
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OtherworldlyInvader posted:On a related note, I think its fair to question the assumption intelligence will inevitably spread out into some sort of interstellar empire. If you're something like the encoded memories of an entire civilization of people uploaded into a hyper computer unified into a galaxy brain super intelligence, why would you want to introduce years long ping times between elements of yourself? Granted, you are immortal, but there's no getting around the math that you could fit a LOT more thinking time into those years if you didn't spread yourself out like that. Even a distance as short as the Earth to the moon is like a 5 second response time, which can be a long time even for us slow thinking meat brains, a Dyson sphere would have even longer times. Even if they send minor elements of themselves to other stars for whatever reason, technologically advanced civilizations/intelligences may be characterized by building their most important elements smaller and more compactly, in order to share more information within themselves. A civilization developing in a dense enough star cluster could conceivably spread fairly easily without FTL over a long enough timescale. They'd have to get lucky to avoid being wiped out by nearby supernovae early on and wait for just the right kind of close encounters to provide small delta v without being too close to disrupt the orbits of either system's planets.
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Dec 10, 2019 07:40
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ashpanash posted:When your speculation rests on the laws of thermodynamics or relativity being wrong, weep for your speculation. The universe would have to be very, very different from what we perceive and experience, in remarkable ways. And nothing we have so far uncovered would continue to make sense. Tell that to string theorists, those guys are nuts! 
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Dec 10, 2019 08:09
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Libluini posted:Tell that to string theorists, those guys are nuts! I do, every chance I get.
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Dec 10, 2019 08:19
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Raenir Salazar posted:First, there's a few assumptions you've made that aren't really correct in the context of the thread, it seems like you maybe read one or two posts and then skipped to the end. Nah I read the whole thing. My issue is that people make very limiting assumptions about what an interstellar civilization might look like. The assumption that spreading out is a good survival mechanic, or is even desirable, is absolutely worth questioning given interstellar distances and the speed of light. For highly technologically advanced aliens with a deep understanding of astrophysics and unbelievably vast quantities of processing power, the chances of being blindsided by a cosmic natural disaster may be effectively 0, and with advanced technologies they may develop better contingency plans for them than writing off major chunks of themselves. The only existential threat to such an entity may be another highly technologically advanced entity... which they run the risk of creating themselves by spreading themselves so distant they're unable to maintain a cohesive whole. The point I'm questioning isn't if interstellar travel is possible (there's no reason to assume it's not, even if it seems a daunting engineering challenge to us today) but how intelligence capable of interstellar travel would desire to structure its self, and how those desires may interact with known constraints of the universe. This is also operating on the assumption that the most desirable place to live in the universe is always going to be near a star. For aliens with advanced materials and energy technology it's possible quick access to mundane metals/rock/ice/gas and radiated solar energy is no longer needed or perhaps even not desirable for whatever it is technologically advanced aliens want to do. To advanced aliens, free solar power from a star might be about as wanted as a free cave is to a human with a penthouse apartment in the big city. Maybe the gravitational fields in a solar system interfere with their computer systems which are pushing up hard against the very edge of miniaturization allowed by the physical laws of the universe so they've moved to a void between filaments in the intergalactic medium (which is really quite embarrassing I mean they're 34 million years old as a space-faring civilization and all they do anymore is play video games). Basically I don't think we should assume that [People on a Planet] > [People on a bunch of Planets at different stars] is the natural or inevitable progression for a human-ish species who's developed advanced capacity for interstellar or even interplanetary travel. Libluini posted:Except our math and physics could be all wrong, for all we know (which is not much). Essentially, we got far enough into the essence of the universe, finding out even more becomes a slower and slower struggle with each new tidbit of information collected. And a lot of this new information is basically guesswork, as new experiments to falsify the wrong stuff gets harder and harder the further we progress. In fact, some scientists think the combination of new experiments (like data collected from the LHC, for example) only confirming what we already think we know with the existence ongoing cosmic riddles like dark matter and dark energy means we got something seriously wrong somewhere on the way. The question of FTL travel its self is an artifact of human language and growing up in an environment where we've never had to experience or think in relativistic frames of reference. If Vulcans landed on Earth tomorrow and we eagerly asked them if FTL travel is possible, their response would probably be to think their universal translator was broken because we're talking in word salad. It might help to look at it this way: What would be the ultimate expression of FTL travel? To travel instantaneously any distance, right? We don't have to imagine what this would look like to an outside observer, there are things in the universe which do just that: travel any distance in 0 time and we can observe how they behave. All of them travel at the speed of light. If something traveling infinite distance in zero time taking 100,000 years to cross the galaxy doesn't make any sense, its because we're all human and grew up on planet Earth where none of that was relevant when we built our understanding of the world. It runs completely contrary to how we experience the world from the moment we're born to the day we die and so people have trouble understanding and believing it. None of this will probably sway you at all, because when I believed FTL travel might one day be possible it never swayed me at all until I banged my head into it enough times to realize fundamental assumptions I made about the basic nature of time and space had been conclusively proven false for like the last 100 years by people who are way smarter than I am.
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Dec 10, 2019 08:54
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OtherworldlyInvader posted:It might help to look at it this way: What would be the ultimate expression of FTL travel? To travel instantaneously any distance, right? We don't have to imagine what this would look like to an outside observer, there are things in the universe which do just that: travel any distance in 0 time and we can observe how they behave. All of them travel at the speed of light. If something traveling infinite distance in zero time taking 100,000 years to cross the galaxy doesn't make any sense, its because we're all human and grew up on planet Earth where none of that was relevant when we built our understanding of the world. Correction here - things moving at the speed of light don't travel infinite distance in 0 time. They travel 0 distance in 0 time. Space and time are inextricably liked together. To experience 0 time would necessitate experiencing 0 space. And that is exactly what happens - the universe becomes two-dimensional in the direction of travel (to the extent that we can take a limit of an object approaching the speed of light, that is - mathematically speaking, an object at the speed of light *has no* reference frame at all).
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Dec 10, 2019 09:02
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Libluini posted:Except our math and physics could be all wrong, for all we know (which is not much).
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Dec 10, 2019 09:44
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OtherworldlyInvader posted:Nah I read the whole thing. My issue is that people make very limiting assumptions about what an interstellar civilization might look like. The assumption that spreading out is a good survival mechanic, or is even desirable, is absolutely worth questioning given interstellar distances and the speed of light. For highly technologically advanced aliens with a deep understanding of astrophysics and unbelievably vast quantities of processing power, the chances of being blindsided by a cosmic natural disaster may be effectively 0, and with advanced technologies they may develop better contingency plans for them than writing off major chunks of themselves. The only existential threat to such an entity may be another highly technologically advanced entity... which they run the risk of creating themselves by spreading themselves so distant they're unable to maintain a cohesive whole. This argument is complete nonsense though, as by now everyone knows "FTL-travel" is just a mental shorthand for whatever twisting of space to generate shortcuts is or isn't possible. No-one argues FTL means literally propelling something faster than light So yes, FTL is a term grown linguistically out of how we perceive time and space, but making that fact the linchpin of your argument is incredibly wrongheaded. You're basically arguing like an alien being which has had only fleeting contact with Human culture MSDOS KAPITAL posted:In addition to what others have said, I want to also point out that basically all scientific advancement and discovery, especially in the last 250 years, consists of refining and extending existing knowledge. We're not going to find out that "all our math and physics is wrong" any more than we're going to wake up one morning to discover that down is up and the moon is made of green cheese. Any new scientific discovery will have to explain all hitherto evidence and observation, including the ones that currently lend very strong support to the theory of relativity and all the accompanying "limitations" it places on our ambitions for intergalactic empire or whatever the hell. Which is to say, that any new scientific discovery which tells us that no, really, we can do FTL after all must also, far from overturning relativity, contain it. I'm not saying that squaring that particular circle is completely outside the bounds of "what could happen," but at this point to call it far-fetched would be a massive understatement probably unequaled in the history of science. Yeah, that's the core of the problem, essentially. As I explained further after that top sentence, every new observation nowadays creates more and more work to fit into our theories. Just one simple example is our theory of how planetary systems form: After we confirmed more and more exoplanets, it turned out the theory we had built using our own system as the only reference was wrong, or at least incomplete. Exoplanets like Osiris (Jupiter-like, hot, very close to their sun) should not have been possible according to the old theory, so years of hard work was necessary to incorporate the new data. And that was just a simple problem with a simple, but tedious solution. But modern physics is full of crap like dark matter, where physicists are desperately hoping they'll eventually find something. Though with each passing year without detecting WIMPS or whatever, the ugly thought rises that we took a wrong turn somewhere.
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Dec 10, 2019 10:29
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Libluini posted:This argument is complete nonsense though, as by now everyone knows "FTL-travel" is just a mental shorthand for whatever twisting of space to generate shortcuts is or isn't possible. No-one argues FTL means literally propelling something faster than light It's still not better, just shifting the problem. Essentially everything we have on this matter is a mathematical curiosity. Warp drives and almost every kind of wormhole - 'what if this thing that never goes below zero WAS below zero'. Some 'physically meaningful' kinds of wormhole cannot be made, it would need to be embedded since the start. And even the most mundane ones, like the Einstein-Rosen bridge are not physically useful - ER bridges collapse under any outside energy, including the energy you are trying to move through them; and the analytical continuation of a Kerr black hole is, well, an analytical continuation which might not be physically meaningful. And also collapses with any outside influence. It is also not clear where the extensions in the spacetime diagram would even lead. Side note: my thesis advisor wrote papers with the science advisor on Interstellar. A lot of this cool stuff actually works in the extreme gravity of a Kerr black hole, especially love.  But that is a far cry from any FTL like tech being possible.Of course, gravitational waves were initially dismissed as a mathematical curiosity until Feynman realised you can extract energy from them, and therefore they are physically meaningful. So maybe it should not be dismissed so readily - but then we run into problems with causality etc. Were I a betting man, I would say speed of light is as fast as information of any kind can meaningfully transfer, and there is no way to 'beat' the light cone with spacetime tricks. quote:And that was just a simple problem with a simple, but tedious solution. But modern physics is full of crap like dark matter, where physicists are desperately hoping they'll eventually find something. Though with each passing year without detecting WIMPS or whatever, the ugly thought rises that we took a wrong turn somewhere. That thought only rises among a fringe of physicists pushing their pet 'solutions'. To have a solution, you need a problem, and since we haven't directly observed dark matter, it's an attractive place for that fringe. In fact, my own university has a sizable (2 people) fringe of people fighting an uphill battle against just a single bit of observational evidence for dark matter (rotation curves of certain galaxies), and they made very little progress. At the same time, their solutions cannot make a single dent in cosmological proof, or nucleosynthesis, or microlensing studies. To be even more specific, just a couple weeks ago, both NASA and China released papers that suggest multitudes of galaxies without appreciable dark matter. Contrary to what you might think, that is proof in favor of lambda-CDM, as if the mechanism was not a massive particle, you would expect it to behave uniformly in every galaxy. In fact, with each passing year we get more and more data that suggests our understanding of dark matter's influence is correct. The explanation for not having directly detected the particle can be very, very simple - maybe it doesn't meaningfully interact even weakly in non-big bang level conditions. Even neutrinos - a Weakly Interacting Massive Particle we know exists, by the way - are ungodly difficult to detect. An interesting place to study, and a good place for ideas? Sure, just like thinking up FTL mathematical curiosities in relativity. Somewhere we should expect a revolution in scientific thinking? Eh, probably not. dex_sda fucked around with this message at 13:34 on Dec 10, 2019 |
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Dec 10, 2019 13:31
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Btw, this reminds me of the whole EMdrive debacle. Nearly every reputable physicist said that the claim was suspect at best (aka. basically nonsense borne of a bad experiment), but they were shouted down in media both social and mainstream. Turns out the whole thing was pretty much Lorenz force from the Earth's magnetic field in the cable. But you'd be hard pressed to find that particular tidbit of information making the rounds. I think that might promote sloppiness in science going forward 
dex_sda fucked around with this message at 13:38 on Dec 10, 2019 |
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Dec 10, 2019 13:36
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On a similar note, have you actually worked through the EMDrive guy’s argument, and following his chain of reasoning, found the flawed step? I asked the physics thread this, and no one did it, instead (and don’t get me wrong, correctly) arguing that since it violates conservation of momentum, his argument must be wrong. Still, it can be interesting to follow the argument and find the flaw.
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Dec 10, 2019 14:08
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I think it’s lazy to ignore that many human cultures have a history of sending people out beyond contactable distances to explore and expand when preaching some ‘no species would ever lessen its computing power’ argument that you’ve pulled from your rear end. Making a ton of assumptions and acting smugly like you must be correct because of those assumptions is a really silly way to contribute to a conversation, especially about possible future tech, but double especially when your argument rests on ‘humans definitely won’t do something stupid like go explore the unknown just to see what’s there.’
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Dec 10, 2019 14:59
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OtherworldlyInvader posted:Nah I read the whole thing. My issue is that people make very limiting assumptions about what an interstellar civilization might look like. The assumption that spreading out is a good survival mechanic, or is even desirable, is absolutely worth questioning given interstellar distances and the speed of light. Stars die, there's finite amounts of resources on a given world, overpopulation, politics, discrimination, religious persecution, another alien species arriving and displacing you, there are also hundreds of different ways your species can be wiped out, many of which we ourselves have easily speculated upon despite barely making it to the moon. Gamma ray bursts, supernova, stray comets or space rocks. There is zero means of surviving any of these with a fully developed and populated planets with 99% of your population intact that does not involve going off world. There are no systems of bunkers dense enough, deep enough, or strong enough to resist a space rock. Additionally the intersellar distance and the speeds we are likely limited to, aren't even particularly daunting for us. People have no problems speculating about generational colony ships transporting a small city's worth of people over hundreds of years to reach a new Eden. We can reach nearby stars *right now* with just 1970's technology; it isn't ideal technology but we can certainly improve upon it. There is no "given", your assumptions just seem wrongheaded. What *is* given is virtually *all* life on Earth follows broadly very similar processes and survival strategies. We have precious few examples of quasi immortal static life forms; I think there's just one? All other life, from bacteria to cancers, to trees, to viruses, to mammals, to insects, everything; all does the same thing. Reproduces, passes down genes, and spreads and consumes while natural selection prunes some of the chaff. Any discussion about "survival strategies" that doesn't accept and acknowledge the evidence we can already observe is just being contrarian. quote:For highly technologically advanced aliens with a deep understanding of astrophysics and unbelievably vast quantities of processing power, the chances of being blindsided by a cosmic natural disaster may be effectively 0, and with advanced technologies they may develop better contingency plans for them than writing off major chunks of themselves. The only existential threat to such an entity may be another highly technologically advanced entity... which they run the risk of creating themselves by spreading themselves so distant they're unable to maintain a cohesive whole. There is no contingency to survive a gamma ray burst; there is zero amount of computational power or technology without venturing into science fantasy bullshit like forcefields and blackhole power generation at which point you might as well throw in FTL and colonies! There's no reason to presume these hypothetical space gods WOULDN'T spread out; you're begging the question. quote:The point I'm questioning isn't if interstellar travel is possible (there's no reason to assume it's not, even if it seems a daunting engineering challenge to us today) but how intelligence capable of interstellar travel would desire to structure its self, and how those desires may interact with known constraints of the universe. We know how we'd structure ourselves. We'd have no structure. We'd just be however many independent civilizations co-existing over a massive empty galaxy to ourselves. Because Faster than Light interstellar travel isn't possible (that we can yet imagine), and the communications beyond the nearest stars too long a delay for meaningful integration beyond the nearest of stars. It's one thing to like want to speculate, but I don't really have the patience or desire to walk you through why spreading out is the most likely survival mechanic and past a certain point if you're just going to explain some key points. quote:This is also operating on the assumption that the most desirable place to live in the universe is always going to be near a star. For aliens with advanced materials and energy technology it's possible quick access to mundane metals/rock/ice/gas and radiated solar energy is no longer needed or perhaps even not desirable for whatever it is technologically advanced aliens want to do. To advanced aliens, free solar power from a star might be about as wanted as a free cave is to a human with a penthouse apartment in the big city. Maybe the gravitational fields in a solar system interfere with their computer systems which are pushing up hard against the very edge of miniaturization allowed by the physical laws of the universe so they've moved to a void between filaments in the intergalactic medium (which is really quite embarrassing I mean they're 34 million years old as a space-faring civilization and all they do anymore is play video games). What if they also possess magic powers. You started with, "What if surviving isn't desirable" to "What if space magic and sufficiently advanced aliens?" so I'm a little confused about your point; if you wanna speculate about scifi and aliens and poo poo, its in the thread title go nuts; but I think you should be clear which problem space you're operating in because you're now being very confusing as to what you're arguing.
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Dec 10, 2019 15:13
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Returning to the Fermi paradox - OtherworldlyInvader mentioned that a highly advanced civilization might opt to build Dyson spheres to support their vast energy needs, and might not want to send emissaries to other systems because of the lag-time in communication between interstellar distances. I think that, if it was being put forward as a possible Fermi solution, it's reasonable enough. It's totally on point with the main themes and questions of this thread, so we shouldn't just dismiss or gloss over that point in our rush to defend interstellar colonization. The question is, then, why haven't we detected Dyson spheres yet? A Dyson sphere should be fairly visible in the cosmos, appearing as a point that strongly radiates waste heat in the infrared rather than the visible spectrum. So if we were, for example, to do a sky study looking for points in the heat part of the spectrum, we should be able to detect them. As far as I know, we haven't found anything quite like it -- "Tabby's Star" seems like it's pretty well explained by clouds of dust and gas, I think. For the record - I don't believe that FTL/Wormholes/Warp Drives are possible. EDIT: Hm, what if that's a possible Dark Matter candidate? What if the Dark Matter halo around some galaxies is actually the extremely cold megastructures of some highly advanced alien civilization? EDIT2: My point being - this person isn't Kerning Chameleon, so don't rush to tear their post down. DrSunshine fucked around with this message at 15:42 on Dec 10, 2019 |
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Dec 10, 2019 15:36
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DrSunshine posted:
I'm gonna give the answer that is always the answer for this stuff: we haven't detected poo poo yet. People talk about aliens in this framework like we've done some exhaustive search of the universe and looked under every rock and nothing is out there. The most complete SETI program has scanned 20% of the sky in one spectrum. The first confirmed planet not in our solar system wasn't until 2003. We aren't even sure we have found all the planets in our OWN solar system we are so in our infancy with astronomy. We haven't found any dyson spheres because the dyson sphere detection program is like, not a thing that exists yet and the programs that would find it incidentally would not be looking for it and certainly wouldn't write an anomaly off as "well it's aliens guys'
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Dec 10, 2019 15:43
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silence_kit posted:On a similar note, have you actually worked through the EMDrive guy’s argument, and following his chain of reasoning, found the flawed step? From what I remember, the EMDrive guy didn't have an argument either, he just built this thing and measured some thrust from it. When he attempted to explain it in some way, he had to resort to weird, utterly nonsensical poo poo like 'bouncing off pilot waves' in order to explain how it worked.
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Dec 10, 2019 15:44
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I found this article looking for "Fermi's paradox" + "Dark matter" + "alien civilizations". Read it if you are a bit into  speculative articles written by astrophysicists.
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Dec 10, 2019 15:46
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Sure, dark matter could be discarded alien space stations all cooled to nearly 0K, as long as you throw away all of modern cosmology and galaxy formation and ignore the absence of evidence for MACHOs.
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Dec 10, 2019 16:17
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eXXon posted:Sure, dark matter could be discarded alien space stations all cooled to nearly 0K, as long as you throw away all of modern cosmology and galaxy formation and ignore the absence of evidence for MACHOs. I mean, it could also be WIMPS, as long as you ignore the absence of evidence for WIMPS.
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Dec 10, 2019 16:43
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DrSunshine posted:EDIT2: My point being - this person isn't Kerning Chameleon, so don't rush to tear their post down. I somewhat hedged the way I wrote my post under the idea that maybe the poster just wants to speculate scifi stuff, which is fine. I'm a little bit side eye'ing the first paragraph which seems a little "just asking questions" like, "how can we know surviving is good?" which gets really weird when the posters allows for sufficiently advanced aliens; I'm not sure if the poster is in fact just presenting a hypothetical solution; or if they're being insistent that their pet theory that spreading out actually isn't the "wise" thing to do, ergo why no aliens; parts of it are honestly kind of strange.
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Dec 10, 2019 17:09
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I thought WIMPs and MACHOs were out of fashion in favor of Axions in regards to a dark matter candidate. Why do people think there's only one option for what dark matter is? it could be like 4-5 different phenomenon that we don't know anything bout. Hell there could be an entire class of fields and associated particles that the standard model just fails to encapsulate.
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Dec 10, 2019 17:29
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Heck Yes! Loam! posted:I thought WIMPs and MACHOs were out of fashion in favor of Axions in regards to a dark matter candidate. Then you'd have to ignore the absence of evidence for Axions! quote:Why do people think there's only one option for what dark matter is? it could be like 4-5 different phenomenon that we don't know anything bout. Hell there could be an entire class of fields and associated particles that the standard model just fails to encapsulate. The point is, whatever it is that we're detecting, we don't have a good handle on it, because none of the theoretical explanations we have are backed by any empirical evidence. Just assumptions and appeals to whatever is the "simplest" or most "parsimonious" explanation, mostly forgetting that nature does not care what we find appealing or beautiful or parsimonious. It does what it does.
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Dec 10, 2019 18:12
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ashpanash posted:Then you'd have to ignore the absence of evidence for Axions! Well yeah, the only evidence we have is gravitational interactions. We're just throwing ideas at the wall at this point to see what sticks. ashpanash posted:The point is, whatever it is that we're detecting, we don't have a good handle on it, because none of the theoretical explanations we have are backed by any empirical evidence. Just assumptions and appeals to whatever is the "simplest" or most "parsimonious" explanation, mostly forgetting that nature does not care what we find appealing or beautiful or parsimonious. It does what it does. I hate the appeal to simplicity argument. poo poo is not going to be simple at this point. there isn't some short simple equation to solve everything, and people need to stop pretending like it's out there just waiting to be found. We likely know of a very small portion of the total sum of particles, fields, and the possible interactions between them, and adding more isn't going to simplify anything.
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Dec 10, 2019 18:50
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dex_sda posted:It's still not better, just shifting the problem. Essentially everything we have on this matter is a mathematical curiosity. Warp drives and almost every kind of wormhole - 'what if this thing that never goes below zero WAS below zero'. Some 'physically meaningful' kinds of wormhole cannot be made, it would need to be embedded since the start. And even the most mundane ones, like the Einstein-Rosen bridge are not physically useful - ER bridges collapse under any outside energy, including the energy you are trying to move through them; and the analytical continuation of a Kerr black hole is, well, an analytical continuation which might not be physically meaningful. And also collapses with any outside influence. It is also not clear where the extensions in the spacetime diagram would even lead. I think the Einstein-Rosen Bridge isn't possible at all, at least I've read on Wikipedia/Scientific American that an Einstein-Rosen Bridge is defined as a wormhole between a black hole and a white hole and since we never found evidence for white holes, they probably don't exist. Do wormholes between two black holes have their own term to describe them, or are people just calling them Einstein-Rosen Bridges anyway? On the galaxies without dark matter thing, I believe I've read something about that on Scientific American, too. Wasn't there a controversy about how the observations of seemingly dark matter-less galaxies were interpreted or were the new papers after that and about something even newer? But at least I would hold back before judging this new development. I've read Sabine Hossenfelder describing how the diphoton-thing went down and I was embarrassed by proxy by all the time that was wasted by what was essentially, just white noise in the LHC-data. If the new papers hold up, fine. I'd like to have this dark matter problem solved, too. DrSunshine posted:The question is, then, why haven't we detected Dyson spheres yet? A Dyson sphere should be fairly visible in the cosmos, appearing as a point that strongly radiates waste heat in the infrared rather than the visible spectrum. So if we were, for example, to do a sky study looking for points in the heat part of the spectrum, we should be able to detect them. As far as I know, we haven't found anything quite like it -- "Tabby's Star" seems like it's pretty well explained by clouds of dust and gas, I think. For all we know, we may already have found some Dyson sphere-like constructions. Some of the systems near us behave oddly, with something dimming the light in regular patterns. All the conventional explanations for the observations so far (dust clouds, really dense Oort clouds, etc.) have certainly been plausible, but non of them cover all aspects of the observations perfectly. There's always something missing were astronomers have to shrug and wait for better data. My personal bet is 5% chance of at least one of them being aliens. 
Libluini fucked around with this message at 19:56 on Dec 10, 2019 |
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Dec 10, 2019 19:54
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Libluini posted:But at least I'll hold back before judging this new development. I've read Sabine Hossenfelder describing how the diphoton-thing went down and I was embarrassed by proxy by all the time that was wasted by what was essentially, just white noise in the LHC-data. Yeah, the 750 GeV diphoton anomoly was pretty embarrassing, even as it was happening. You always want to explore such things, sure, but there were lots of red flags right from the get-go, in particular the look-elsewhere tests showed a much more tenuous bump that looked almost exactly like a statistical fluctuation. But theorists gonna theorize, and something like 700 papers were submitted to the arXiv about what it could be? Yeah, it was nothing. Which made sense. It looked like a statistical fluctuation and if real, a resonance that noticeable at that energy scale, surrounded by nothing else, was a real stretch in the first place. It never came close to the 5 sigma generally accepted for a discovery, but people were salivating over it, because they have had nothing to grasp on to for years.
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Dec 10, 2019 20:05
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Libluini posted:I think the Einstein-Rosen Bridge isn't possible at all, at least I've read on Wikipedia/Scientific American that an Einstein-Rosen Bridge is defined as a wormhole between a black hole and a white hole and since we never found evidence for white holes, they probably don't exist. Do wormholes between two black holes have their own term to describe them, or are people just calling them Einstein-Rosen Bridges anyway? A wormhole exiting in a black hole is called a white hole.
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Dec 10, 2019 20:31
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Doesn't String Theory posit that wormholes connected and are proped open by cosmic strings could exist and not have the same issues as Einstein-Rosen bridges?
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Dec 10, 2019 20:42
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Raenir Salazar posted:Doesn't String Theory posit that wormholes connected and are proped open by cosmic strings could exist and not have the same issues as Einstein-Rosen bridges? String theory posits a lot of things that are complete nonsense, so it's sort of a moot point.
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Dec 10, 2019 20:46
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It's deep in the math but String Theory posits that we all have five butts.
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Dec 10, 2019 20:48
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Yeah, String theory tries it's hardest, but after so many years of failures, it's stopped being cute and has grown rancid
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Dec 10, 2019 20:49
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Libluini posted:Yeah, String theory tries it's hardest, but after so many years of failures, it's stopped being cute and has grown rancid But wait, if we shove our heads up our asses far enough using counter clockwise rotation, we may be able to come up with a testable hypothesis that our poo poo don't stink.
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Dec 10, 2019 20:51
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The latest nonsense is the many-worlds interpretation and multiverses in general. A lot of effort is being put into utterly content-less navel-gazing. Which, I suppose, is apropos for today's culture.
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Dec 10, 2019 20:53
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Even within the monkeycheese world of string theory, Cosmic Strings are primordial and would predate even the earliest possibly primordial black holes.
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Dec 10, 2019 21:02
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ashpanash posted:The latest nonsense is the many-worlds interpretation and multiverses in general. A lot of effort is being put into utterly content-less navel-gazing. Which, I suppose, is apropos for today's culture. I'll believe in the multiverse the day someone blows his rear end up because the ruby he picked up turned out to be an oscillating hyperspace crystal and not one day earlier.  To make this reference a bit less obscure: In the massive German SF-series Perry Rhodan, physics has expanded to encompass some sort of "hyperspace", enveloping the realm of matter like a shell and there are visible interactions between hyperspace and normal space you can openly observe, like gigantic Tryortan Maws (rifts into normal space that show up when hyperspace gets hit by wild fluctuations commonly known as "storms") eating a planet or a space ship here or there. Oh, and over the course of the series, it turned out that if you get too deep into hyperspace, you may exit the wrong way and end up in another universe altogether. I could go on and on with this, but the important point: To make the multiverse real, PR had to basically invent completely new types of physics. Physics based on fictional observations that don't exist in the real world because hyperspace doesn't exist in the real world So my take on this matter is, if you start talking about the multiverse, I'd expect you to show me a working transuniversal gate at the bare minimum, or I'll just quietly nod and put your words into the Sci-Fi part of my brain.
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Dec 10, 2019 21:17
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ashpanash posted:The latest nonsense is the many-worlds interpretation and multiverses in general. A lot of effort is being put into utterly content-less navel-gazing. Which, I suppose, is apropos for today's culture. If the strongest point of your thesis is the anthropic principle, you should maybe think about starting over. I really like SpaceTime's video series on this topic. https://www.youtube.com/watch?v=XglOw2_lozc
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Dec 10, 2019 21:17
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OtherworldlyInvader posted:The question of FTL travel its self is an artifact of human language and growing up in an environment where we've never had to experience or think in relativistic frames of reference. If Vulcans landed on Earth tomorrow and we eagerly asked them if FTL travel is possible, their response would probably be to think their universal translator was broken because we're talking in word salad. Libluini posted:This argument is complete nonsense though, as by now everyone knows "FTL-travel" is just a mental shorthand for whatever twisting of space to generate shortcuts is or isn't possible. No-one argues FTL means literally propelling something faster than light The ultimate expression of FTL travel is "FTL = Time Travel". That's important for both for having these discussions and for imagining what could be if FTL by warp travel like in Star Trek were possible (Star Trek has never considered this seriously even in its time travel plots). If the Vulcans showed up tomorrow, they could figure out what we meant when we asked if they traveled faster than light to get here. The actual question is, "Did you break causality to come here?" That's what asking about FTL means. Yes, at this point most people are aware there's a light barrier that can't be broken and has to be side stepped. Warp drives do that with a bubble/wrinkle of space, hyperdrives do that by entering a different dimension, and wormholes do that by creating a shorter path between two points in space. Atomic Rockets has a great and lengthy article on the implications of FTL since it's an unavoidable sci-fi topic. Project Rho posted:However, very few SF novels deal with the second problem. The aphorism at rec.arts.sf.written goes "Causality, Relativity, FTL travel: chose any two."
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Dec 10, 2019 21:26
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FTL itself isn't specifically in to the past time travel. It just allows time travel by moving between referance frames. Which like, I guess if you are doing something so weird and it messes up causality that would suck but consequences being weird if you take them to the edges doesn't mean they can't happen. "It would be too weird" isn't really an argument against something being real. "FTL can't be real because then you could do crazy poo poo I don't like the sound of" is a pretty weak concept. Even if I agree messing up causality sounds like a bad plan.
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Dec 10, 2019 21:34
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LtStorm posted:The ultimate expression of FTL travel is "FTL = Time Travel". That's important for both for having these discussions and for imagining what could be if FTL by warp travel like in Star Trek were possible (Star Trek has never considered this seriously even in its time travel plots). Could someone, without calling me an idiot or a moron, explain why going faster than light is considered impossible? We know the speed of light. Why could no technology every created go faster than that exact speed? Can someone explain it to me like I'm a child.
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Dec 10, 2019 21:59
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1glitch0 posted:Could someone, without calling me an idiot or a moron, explain why going faster than light is considered impossible? We know the speed of light. Why could no technology every created go faster than that exact speed? Can someone explain it to me like I'm a child. It comes from special relativity, and comes out as a consequence of the mass-energy equivalence - E=mc^2. Without getting into the math of it, accelerating requires energy, and energy is the same as mass. It only becomes relevant as you approach the speed of light, but essentially it becomes exponentially more and more energy-intensive to accelerate something the closer and closer you get to light speed, because the faster you go, the more massive you are because the more energy you have. This means that you would require infinite energy to accelerate to light speed. You are not a moron. 
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Dec 10, 2019 22:03
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