Re: Dark energy-powered devices
Here’s another idea I just came up with, that doesn’t harness dark energy itself so much as the Hawking radiation of the de Sitter horizon. A civilization could build a sphere around a cold black hole (I.e., a rotating or charged black hole whose Hawking temperature is lower than that of the cosmological horizon; such a black hole would need to be very close to extremal). The sphere would catch the Hawking radiation from the cosmological horizon, and then feed some of it into the black hole in such a way as to further decrease its temperature (by pushing it closer to extremality). The sphere could use the rest of the energy for its own needs. The black hole and the sphere would keep growing over time. -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Dark energy-powered devices
Uh oh, looks like the “giant atom” idea might not work either. I had been under the assumption that dark energy would cause two orbiting bodies to spiral apart. But on second thought, it seems like what would actually happen is that an orbit affected by dark energy would still be stable, it would just have a longer period than it would have had in the absence of dark energy. Thus it wouldn’t gain gravitational potential energy over time. It looks like the best hope now might be for a breakthrough or paradigm shift in cosmology and/or physics. For instance, if something like Jamie Farnes’ dark fluid theory turns out to be true (in which dark energy and dark matter are both the same, negative-mass object). Alternatively, it might be possible to survive a trip through a rotating black hole into another universe, and when that universe’s usable energy is exhausted, just repeat the process ad infinitum. (There’s a lot we don’t know about black holes). -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Dark energy-powered devices
Actually now that I’m thinking about the spring idea some more, it seems like you might be right about it not working. Dark energy will change the shape of the potential energy/displacement curve for sure, making the spring strongly anharmonic. However it doesn’t look like it will result in amplitude increase (negative damping) like I thought. However the orbiting-spheres system still seems to work, though, and there may be other possible devices that function similarly. As far as cosmological-scale black holes are concerned, I’ve got a hunch. I suspect (but cannot prove) that above a certain mass/radius, the Hawking temperature of a black hole would start to increase again, due to dark energy helping give particles a “push” out of the hole. Not only that, but at least some of these particles would be emitted without decreasing the hole’s mass (since the dark energy performed the work needed to bring the particle into existence). A large enough black hole might radiate away visible light and could serve as a “sun” that never goes out. Perhaps by gathering together several galaxies’ worth of matter it might be possible to form such a black hole? Or perhaps there already is one somewhere in the universe, formed by natural causes, in which case all we would have to do is find it. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Dark energy-powered devices
> That would indeed be like a giant atom, so we would have to have a quantum > theory of gravity to know if that would work, and we don't have such a > theory. Quantum theory tells us those orbiting changes could not be in just > any old orbit but can only be in discrete quantized orbits, and the energy > radiated away would not be continuous but would come out in chunks . > Maxwell's equations are only approximately correct. That’s true, but I’m not sure how significant quantum effects (or quantum gravity effects) would be on such a large scale. > I don't think that would work, if it did then if you hung a spring vertically > from a hook in a gravitational field and gave it a small oscillation the > spring's oscillation would get larger and larger until it tore itself apart. > But that's not what we observe. Well, in a gravitational field like Earth’s the force pulling down on the spring is constant (it’s the weight of the spring itself and whatever is attached to it, which doesn’t vary significantly with height over the distances we observe). With a constant rather than an oscillating force, you won’t get amplification of oscillations. Dark energy curves space in a different manner than the presence of an ordinary mass like a planet, so the situations aren’t exactly analogous. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Dark energy-powered devices
I saw a discussion on Physics Forums about an idea similar to yours (involving spools of string steadily unrolling due to dark energy. One poster asked what would happen once the string ran out, the other person said you could just create more length of string with the energy you generated. There is the issue of what happens when the string becomes too long; the force from dark energy would make it snap, even if it were made from carbon nanotubes. I think what makes my ideas different is that they involve oscillatory motion (cycles) rather than linear. I hadn’t seen any ideas like that before. Another dark energy-related problem I’ve been thinking of a lot is how dark energy would affect large (cosmological-sized) black holes. Would the black hole become more massive over time (like reverse Hawking radiation) due to dark energy pulling it apart? Of course the usual equations relating mass to Schwarzschild radius and temperature, etc. would no longer hold. -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Dark energy-powered devices
It appears as though it would indeed be possible to build a device powered by dark energy. Such a device could keep running forever (as long as the universe keeps expanding forever and vacuum decay doesn’t occur) and be able to survive (or prevent) the heat death of the universe. Even proton decay would not present a problem; new protons could always be created from the energy generated. So far I’ve thought of two possible classes of device that could do this. The first is the “giant atom”, consisting of two spheres of equal but opposite charge orbiting each other at an extremely long distance (long enough that dark energy becomes significant). At such a distance, dark energy would cause the objects’ orbits to spiral further and further apart. On the other hand, because the objects are charged, they radiate away energy as they orbit, and this radiation provides a braking force that would cause the objects to spiral closer together. If the two effects are perfectly balanced, the orbits would be stable and the system would keep radiating away energy forever—energy extracted from the acceleration in the universe’s expansion. The second device consists of an extremely long spring. Due to dark energy, the spring experiences a fictitious force pulling it apart. This force is stronger when the spring is fully extended, due to the longer distance between the ends. Thus an oscillating spring would experience an oscillating force, and have energy continually added to it, increasing the amplitude of its oscillations. To keep the string from breaking, a mechanism for extracting energy from the spring would have to be added, and if energy is extracted at the same rate it is added the system would be stable. As far as I know, neither of these devices has been proposed before in the literature; I might have been the first person to come up with them. Perhaps we should look for signs of these devices being constructed, in the event highly advanced alien civilizations might be constructing them. Any civilization that constructs such a device would probably qualify as Type IV. With infinite energy it’d be possible to do an endless variety of things: run a universal dovetailer, or resurrect the dead (simply by resurrecting every person who COULD have ever existed, a set that obviously includes every person who DID actually exist), etc. -Mason Green -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Solomonoff induction and mechanism
Solomonoff’s method of induction seems like a good fit for a mechanist view of things. For instance, it could be used to assign a relative probability to the universe being generated by a universal dovetailer: 2^(-K) * m, where K is the Kolmogorov complexity of the universal dovetailer and m is the measure the dovetailer assigns to universes like ours. This formula implies that a (more complex) non-universal dovetailer might be preferable _if_ it assigned a much higher measure to universes like ours. Such a dovetailer might, for instance, output only (or mostly) habitable worlds, instead of outputting mostly uninhabitable worlds as the standard UD does, and the higher resulting measure would offset the increased Kolmogorov complexity. If we live in a highly “atypical” universe, that might also affect how we should do Solomonoff induction. For instance if we knew that we lived in a universe with much less suffering than an “average” inhabited universe, that could imply we were generated by a dovetailer that doesn’t like suffering. If the opposite is true and we live in a “mean world”, that means we might be generated by a sadistic dovetailer, etc. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: "No black-hole singularities" in an undated loop-quantum-gravity theory
David Deutsch suggested something like this I (that individual universes are discrete, but the multiverse as a whole is continuous). “within each universe all observable quantities are discrete, but the multiverse as a whole is a continuum. When the equations of quantum theory describe a continuous but not-directly-observable transition between two values of a discrete quantity, what they are telling us is that the transition does not take place entirely within one universe. So perhaps the price of continuous motion is not an infinity of consecutive actions, but an infinity of concurrent actions taking place across the multiverse.” January, 2001 The Discrete and the Continuous -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Decisions, decisions...
So I thought of an interesting problem in decision theory and/or ethics. Maybe someone’s thought along these lines before, but if so I haven’t encountered it. Suppose you have to make a decision between two options, A and B. Your credence that option A is the more ethical one is 60%, and your credence that option B is the more ethical one is 40%. Is it more ethical to 1. Automatically pick A because it has the higher credence. 2. Pick randomly between A and B with the probability of each one matching your credence. For example, generate a random number between 0 and 1 and pick B iff your number is over 0.6. If one subscribed to the MWI, the second option could even be phrased as “make sure 60% of your future selves pick A and 40% pick B”. The second option could be called the diverse-futures ethic, since it would lead to a more varied future if everyone consistently followed it, while option A could be called the winner-take-all ethic. One interesting fact is that it’s less costly (in terms of entropy and energy) for an agent to follow the diverse-futures ethic. This is because noise can be recycled from the environment to use to make the decision. However the difference in cost is very small (less than 1 bit of entropy in the above case, or less than kT ln 2 of energy). Maybe that should factor into the relative ethical merit of the two strategies, if only a tiny bit. The human brain seems to follow the diverse-futures ethic since it calculates probabilistically, using ambient noise to its advantage. -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Class calculus and conscious AIs
Hi, I’m wondering if any of you have read this paper and if so, what do you think about it. The author says he’s discovered a new kind of mathematics that could give rise to machine consciousness. A few other publications picked it up but it got surprisingly little fanfare, for such a bold claim. https://arxiv.org/pdf/1804.03301.pdf -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Black holes and computational complexity
Leonard Susskind thinks there may be a link between the size of a black hole’s interior (which grows with time) and its computational complexity (which does likewise). At the end of the article there’s even a suggestion that the expansion of the universe might likewise have a computational origin. https://www.quantamagazine.org/why-black-hole-interiors-grow-forever-20181206/ -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Extended Wigner’s Friend
To go into further detail, creatures who perceived time that way would not be able to maintain a sense of personal continuity or selfhood for very long, since they have many future “selves” and past “selves”. So instead, they prefer to think of their future and past “selves” as other people more like cousins or family. A consequence of this is that they are always changing their names as time passes; they are literally becoming different people as time passes because each observer-moment is a different person blending into other people. “Schizophrenia with a vengeance”, indeed! Definitely a good sci-fi idea. Thanks for the story idea, guys! I’d never have come up with it without this discussion. -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Extended Wigner’s Friend
Ah, yes, multiple histories. Given only what we know now about the universe (and not what we “remember from before”, since our memories are actually just patterns encoded in our brain at the present moment), what’s to stop us from thinking that entropy was higher in the past and things just spontaneously arranged themselves into the present low-entropy state? In other words, the second law of thermodynamics might not be true and the arrow of time could be more of a parabola with our present selves at the bottom. That ripe banana in your hand might have been rotten 6 days ago. If multiple histories is true, then MOST (by probability amplitude) of the universe’s histories are paradoxical in this way, since there are more possible pasts with high entropy than there are with low entropy. Furthermore these counterintuitive histories might be weird in other ways (for instance, some of them might not feature a Big Bang or expanding universe at all, but rather the light distribution just fluctuated in such a way as to mimic one). Everything we think we know about “the past” might come into doubt if MWI and multiple histories are true. I once tried asking this question on Physics Forums but it got deleted for being too weird. Apparently they don’t like anything that upsets their common sense too much. Actually I find the idea that the past is not as it seems to be oddly fascinating. I’m thinking I might write a story about beings who perceive time as parabolic, with their present selves at an entropy minimum: their language is structured so that they can only talk about possible pasts and not “the” past, and also they have words for all the Second Law-violating reverse processes that had to have occurred in the high-entropy majority of their possible pasts. -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Extended Wigner’s Friend
Here’s a recent editorial I found in the magazine arguing against Many-Worlds on the grounds that it denies the reality of experience or the self. (https://www.quantamagazine.org/why-the-many-worlds-interpretation-of-quantum-mechanics-has-many-problems-20181018/) Well, if we don’t want many-worlds or subjectivism, than the only other option looks like it’d be to modify QM itself. Some form of digital physics might work, otherwise we could have objective collapse (either random, or else there’s something/someone outside the universe choosing which path the universe follows). -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Extended Wigner’s Friend
There’s a new article in Quanta Magazine (https://www.quantamagazine.org/frauchiger-renner-paradox-clarifies-where-our-views-of-reality-go-wrong-20181203/) about a thought experiment that poses trouble for certain interpretations of quantum mechanics. Specifically it implies that either 1. there are many worlds, 2. quantum mechanics will need to be modified (as in objective collapse theories), or 3. reality is subjective (solipsism?). Exciting stuff! -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Adam and Eve’s Anthropic Superpowers
Hi everyone, I found an interesting blog post that attempts to refute the Doomsday Argument. It suggests that different worlds ought to be weighted by the number of people in them, so that you should be more likely to find yourself in a world where there will be many humans, as opposed to just a few. This would cancel out the unlikeliness of finding yourself among the first humans in such a world. I’m curious as to what the contributors here think. (I’m new here, I found out about this list through Russell’s Theory of Nothing book). https://risingentropy.com/2018/09/06/adam-and-eves-anthropic-superpowers/ -Mason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
