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Comment Re:In Other Words (Score 1) 413

You did not read what I said, and are inverting the logic. Yes, the Universe manifestly DOES have a few "simple" rules a.k.a. the laws of physics, and HAS produced rocks. But that is literally irrelevant to the point that there is nothing about rocks -- or, if you prefer, the laws of physics and the medium in which they operate -- that appears "designed". The laws are regular mathematical laws and we have no evidence for some sort of highly imaginative "field" of possible mathematical law sets and possible Universal media obeying them that a designer can select from to create the design, let alone evidence for the insane recursion relation in complexity and design implicit on the existence of such a designer.

Any sentient "designer" of a Universe plus their Super-Universe within which it builds the Universe has more complexity (and greater information content) than the Universe that they designed and built. If complexity implies design, then every designer and their Universe must have a still more complex designer in a still more complex Universe. If you wish to assert that this recursion terminates anywhere, so that you can call the designer at that level "God" or "The Master Simulation Programmer", then you no longer assert that complexity necessarily implies a designer, in which case there is no good reason to apply the rule at all even in the first instance without evidence!

Quite aside from this, rocks specifically do not exhibit any of the characteristics we generally associate with designed things, and we have quite detailed mathematical models for the probable history of rocks that do not require or benefit from (in the specific sense of being improved by) any assumption of active design. Neither, frankly, do the laws of physics.

As I pointed out in another thread, the following is a classroom example of incorrect logic:

All men are mortal.
My dog is mortal.
Therefore, my dog is a man.

All computational simulations are discretized.
The Universe is discretized (or not, see other replies).
Therefore, the Universe is a simulation.

You argument is even worse:

Rocks, that do not appear to be designed, can be designed anyway.
Therefore, we can never say that rocks do not appear to be designed.

Say what?

My dog, that does not appear to be immortal, might be immortal anyway.
Therefore we can never say that dogs are mortal.

Sure we can. What you might get away with is the assertion that there is a very small chance that some living dog (including my currently living dog, that isn't dead yet!) might turn out to be immortal. However, every single dog since wolves came out of the cold that was born more than thirty years ago is to the very best of our observational knowledge and theoretical knowledge of dog biology dead as a doorknob and every living dog that any of us have ever seen appears to be aging and we all understand how aging and disease and accidents all limit life. To assert immortal dogs you have to just make stuff up -- invent things like "dog heaven" where all dead dogs run free and have an unlimited supply of bones, or imagine that somewhere there might be a very lucky ex-wolf that failed to inherit an aging gene and that has never had a fatal disease or a fatal accident and that somehow has eluded our observational detection -- so far -- and (ignoring the second law of thermodynamics and the probable future evolution of the Universe based on the laws of physics) assume that that dog will somehow survive longer than the Universe itself probably will. Both of which are pretty absurd.

So I repeat, there is absolutely nothing about rocks that makes us think that they are designed. That does not imply that they might not be designed after all, it is not a logical statement that rocks could not have been designed, it is an empirical statement that, just as dogs appear to be mortal (and not humans, however easy it is for dogs to make the mistake, especially around dinner time:-), rocks appear not to be designed. When I find a rock on the ground as I walk along, I do not quickly look around trying to figure out who designed the rock because it looks so very much like a made thing. Quite the opposite. And, I can almost guarantee, so do you!

Comment Re:In Other Words (Score 1) 413

No arguments. Simulations similarly are generally not "deterministically" scripted. They are constantly rolling (metaphorically) pseudorandom numbers to generate non-repetitive game play. But rocks or gameplay that is "generated" are still generated according to an algorithm that was designed, and I was using the term in this broader sense.

Comment Re:In Other Words (Score 1) 413

I was pointing out (possibly badly) that his argument was a formal fallacy of the general sort: "All men are mortal, my dog is mortal, therefore my dog is a man". "All simulations are discretized. The world we observe is discretized. Therefore, the world we observe is a simulation." Same argument, substitute men/dog/mortal and simulations/world/discretized (or whatever). This is simply an incorrect argument in symbolic logic completely independent of the meanings of the symbols per se, unless I am misremembering my formal symbolic logic.

ELSEWHERE I pointed out that we do not, in fact, know if the world is discretized and that even if it is as far as spacetime is concerned, that doesn't mean that it is discretized in amplitude/phase space. And I am teaching quantum mechanics every Monday, Wednesday and Friday at the moment, so I'm not exactly ignorant about this.

Comment Re:In Other Words (Score 1) 413

Shall I show you my dry stack walls and my mortared fieldstone walls? Besides, this doesn't really impact the argument. The argument is: "Things exist that appear to have functions in a system of interlocked causality. If I were going to simulate this particular system of apparent interlocked causality, I would do so by using things that have these functions so that the result looks like this system of interlocked causality. Therefore, this apparent system of interlocked causality is a simulation because it works the way a simulation of it that I built would work!"

This is an utterly absurd argument. Begging the question doesn't begin to describe it. This is just the argument for God by design dressed up in computer clothing with a side order of Solipsism, and leaves all of the same questions begged and not even acknowledged as "problems". OK, so we are a simulation. Even discretized, the Universe has the information content of at least 10^256! (that's factorial, not exclamation point, all the permutations of all the ways "stuff" can be entered into the apparent cells). Or, of course, as I argued, it could have far, far less information content because all it really has to do is provide a few gigapixels of my apparent visual field, a handful of less dense informational channels for sound, tasted, smell, and touch -- certainly less than a terabyte of information -- and update it according to a set of classical physics rules plus an interactive script. It doesn't even have to do more than one, because if the Universe is a simulation, you could be and probably are a NPC being presented to just me in my VR bodyset -- assuming that in some more fundamental reality I have an actual body and am not MYSELF a self-aware NPC in a simulation being run for things that look like giant amoebic blobs swimming in liquid helium near the cores of gas giants (or in some more bizarre environment as we have no possible way of even speculating about the physics of the world in which the host computer supposedly lies).

We could come damn near building this now -- it's an easy extrapolation of our first rudimentary VR sets. We likely couldn't make it high enough resolution yet, but that's just a matter of scaling of work underway and doesn't require anything like Planck length discretization.

Then there is that computer that we are all running on. One way or another, its information content has to be at least as large as the information content of the Universe being simulated, or Shannon has lived in vain. Furthermore, it has to have an extremely high degree of organization. Indeed, the information content in the physical hardware of any computer ever built -- all the way down to your hypothetical Planck scale -- is almost infinitely larger than the content of its "computational" working memory and processors. Indeed, if one accepts the assertion that real quantum phases etc are real numbers, and meditate on the continuum hypothesis and aleph null and aleph prime, it is infinitely larger. It takes billions to trillions of atoms to represent a single switch, and many switches and other adjuncts to perform even a simple, crudely discretized computation simulating real number arithmetic.

So if you REALLY take the simulation theory seriously, you have to have a Universe somewhere -- somewhere, somewhen, somehow, there has to be a physical basis for the computation, energy and entropy with a set of rules that encodes this massive program -- that has a much, much, much, much.... larger information content than the Universe being simulated. My laptop (plus a remote supercomputer plus a network) can play World of Warcraft and provide me with a very nice simulation shared with a few hundred others (more like a few tens in any given perceptual field representation) based on coarse-grained objects and carefully builts SURFACE representations, because the giant snapping turtles are only shell thick and have no actual internal guts. Even this crude a simulation, skin deep and lacking real depth and transmitting only a shared visual space with added sound effects that don't even try to "share" a sound space, requires ever so much more physical information to represent it.

Now if I were designing a Universal simulation, I would make it self-representing. That is, I would make it its own computer. This makes it information-theoretically compact. The program being run are "the Laws of Physics", and the data being manipulated represents nothing but itself; it isn't stored on something else. Now the simulator for the Universe is the exact size and exact structure of the Universe being simulated, Shannon is very happy, and hey, even the Planck length -- if real -- is now relevant. The only real problem left is that now it isn't a simulation, it is reality itself. And a minor secondary problem -- even if this is how I would design it (if only because I can look around me and see that it works) that doesn't mean that it was designed. One cannot look at something with a given degree of complexity and say "Wow, that's complex! It must have been designed in order to be that complex" without contradicting your own argument with the implicit assumption that there is an even MORE complex layer of reality supporting the designer and the medium in which the design is realized. The only empirical conclusion that is justified and consistent is that what we see is what we get. Reasoning by analogy isn't reasoning at all, either logically or empirically.


Comment Re:In Other Words (Score 5, Insightful) 413

1. Due to limited computational resources, the simulated universe would be granular or "quantum".
2. To limit computation, reality would be held in a fuzzy probabilistic "superposition" state until it is actually observed, similar to how a GPU running OpenGL will skip the generation of hidden polygons.
3. The maximum speed of information transfer would be finite, to limit the propagation of changes through the universe.

All of these are actually true in our universe, ergo, we are very likely a simulation.

And this, sir, is why you really need to consider taking a course in formal logic and maybe learn about logical fallacies.

None of these assertions, even if they were true in some useful way, constitute a statistical or logical argument for the conclusion. This is true at an openly embarrassing level. Suppose one were designing a rock because you wanted to build a rock wall and for some reason didn't want to use actual rocks. Due to the cost of raw materials, rocks would be finite in size. Because you don't want the wall to be boring, rocks would come in many different colors, sizes, and shapes. Because you don't want the fake rock wall to fall down, rocks would be solid, as opposed to liquid, glass, plasma, gaseous.

All real rocks are actually finite in size, come in many different sizes, shapes, and colors, and tend to be solid to the point where "rock solid" is a standard metaphor in human speech. Ergo, all rocks are obviously designed.


Teleological arguments are pure bullshit, which is what the physicist in question (as well as myself, also a physicist) are happy to point out.

When one actually looks at rocks or Universes, there is an utter lack of either evidence or a plausible, consistent, evidence linked chain of reasoning that increases the probability that the notion/hypothesis "Rocks are designed" or "We are living in a computer simulation" is/are true from their rightful place (so far) of 0.0000.....(0 until you get bored with writing 0's)...001 to something with a tiny smidgen of actual measure.

These are not independent assertions, by the way. If you take the assertion that the Universe is a simulation seriously, then rocks ARE designed objects, even though there is absolutely nothing about rocks to suggest that they actually are designed.

One could then deconstruct the truth of each of your statements individually. For example, there is nothing in quantum theory that limits computational requirements -- quite the opposite. Indeed, quantum theory is built on top of complex, non-discrete numbers in every quantum textbook ever written -- C-numbers. That is, quantum objects are described in general by (at least) TWO real numbers, not just one. If you attempt to represent the quantum state of a very simple -- the simplest -- two level quantum system such as |\psi> = A|-> + B|+>, one discovers that it requires two continuous degrees of freedom and that the states of the system map nicely into points on a 3D spherical hypersurface. If you try to describe the most general quantum state of N such 2 level objects, it requires 2^N or so continuous degrees of freedom. Consequently, we are limited in our solutions or simulational studies of fully correlated quantum systems to a tiny, tiny handful of e.g. "two level atoms" -- perhaps 20 to 30 of them -- because one very quickly runs out of computational resources to perform even very small general computations.

Second, you are building a whole mountain of assumptions into what appears to be a misinterpretation of the Planck length. To quote Wikipedia's page on this topic:

There is currently no proven physical significance of the Planck length...

so you are quoting something for which there is no direct evidence as evidence in a bad teleological argument for something for which there is no evidence at all.

You also don't address the actual numbers associated with the Planck length/time. If the Planck length \ell_p is order of 10^{-35} meters, and the visible Universe (alone) is ~10^11 light years across, and a light year is 10^16 meters then there are 10(11+16+35)*3 = 10^{186} cubic Planck lengths in the visible Universe, and making Planck time out of \ell_p/c we end up with another factor of 10^70 x 10^186 = 10^256 discrete space-time points. That's a hell of a lot of data, and one has to compute all of this for all of these time slices.

Now speaking only for myself, if I were building a simulation of the Universe, it would NOT look like this microscopically. That's because when one plays a game with a physics simulation, all one has to do is present a perspective view into a purely classical representation of various surfaces, plus some sounds, plus some sundry nervous/sensations. Humans can't see microscopic things anyway, even with a microscope we don't see microscopic things, we see images that our brains plus some cognitive work identify as microscopic things. I don't have to make a virtual world that has actual simulations of individual viruses to simulate the nervous sensations of "feeling viremic". Reality need never be more than skin deep, perception deep. I'll point out that empirically (there's that word once again) ALL actual reality simulations present precisely this sort of a Universe BECAUSE it doesn't require an enormous representation. When a dark iron dwarf in WoW throws a bomb at you, the simulator doesn't compute the quantum chemistry ot a gunpowder explosion all the way down to the Planck scale, it just manipulates a few pixels and sprites according to a very simple model of what an explosion LOOKS LIKE.

Similarly, it is really irrelevant as to what the "speed of propagation of causality" is in a simulation. It doesn't even matter how fast your computer is, since you are just stacking up large arrays of numbers with some index you are identifying with some sort of discretized timestep. And don't get me started about relativity and simultaneity and the ordering of events separated by spacelike intervals and COMPUTATIONS of all of these things -- suffice it to say that your argument itself is in fact naive and incorrect per point as well as collectively.

Could the world of our experience by a simulation? Sure. Of course it could. And pink unicorns COULD fart rainbow colors. There is nothing fundamentally contradictory about either one, especially when you get to make up the terms that aren't being contradicted.

It's just that we haven't a shred of actual evidence that either assertion is true. Or that the Universe is a made/designed thing. Or that we could somehow DISTINGUISH a designed "real physical" Universe from a designed "simulation, unreal" Universe from the real, undesigned, physical Universe we appear to live in. Teleological arguments are just as dumb in religion as they are in the assertion that we are all living inside "the Matrix" in reality. How could you even know?


Comment Re:Is the tech bubble official yet? (Score 1) 77

As far as I know, nobody has yet devised an experiment capable of determining whether consciousness actually lives in the brain, or whether the brain is a receiver for a consciousness which exists independently of the body.

You mean, aside from all of the usual ones? Like, giving people powerful drugs makes their (my!) consciousness go away? Like the fact that strokes, drugs, alcohol, accidents, and acts of violence that damage the brain tissue make consciousness go away incrementally? Like the fact that when people's brains die, they apparently die (from the point of view of every device built to measure the neural activity that we identify as consciousness in everything with neurons that we have ever studied)? Like the fact that we have working neural models capable of at least a few of the first steps towards consciousness? Like the fact that all of our understanding of science so far, working together, provides not the slightest support for an alternative hypothesis?

Asserting that we have no experiments to determine whether consciousness lives in a brain is like asserting that we have no experiments that refute the possibility that we are all just NPCs in a giant MMORPG Matrix, or asserting that we have no experiments that refute the possibility of hidden nonlocal dimensions in physics, or we have no possibility of proving that Jesus didn't raise the not-quite-dead yet and make blind people walk and deaf people see. Science doesn't work that way, evidence doesn't work that way, as it leaves one stuck in the eternal "lack of evidence is not evidence of lack" for an infinite sea of non-contradictory assertions that could be true.

Heres how it works. Nearly all of that "sea of notions" -- possible true assertions -- is nearly perfectly improbable. Not "false", just -- literally -- not likely to be true, given what we know and the evidence so far. There could be a rock on the far side of the moon carved by chance into a nearly perfect bust of Abraham Lincoln -- not impossible -- but there is no point in wasting precious plausible belief in our ontology on such a hypothesis as there is no evidence that it is true. Furthermore, by doing a statistical study of rock shapes on the earth looking for rocks that actually look like they were carved into human busts with precisely recognizable features, we might even conclude that it is very likely to be false because the particular shapes that make up a human head, neck, and shoulder set are simply unlikely to occur by accident. This is Bertrand Russell's "teapot" argument.

Of course there is one amusing way the teapot could fail. We could send a silver tea set into orbit! Or, we could drop a bust of Abraham Lincoln on the dark side of the moon. Neither of these apply to consciousness, yet, but of course that is the point of the entire "True/Strong AI" enterprise. Which I personally think will succeed within the next ten to twenty years, not to preserve human consciousness but to augment it and exploit it (the AI). We are already augmenting human consciousness through the interfaces we already have -- the fingers and eyes and ears -- to the point where google is a major part of our brains, to the point where I can stream this thought chain out into your brain faster than anyone a mere twenty or thirty years ago would have ever dreamed possible.

So please, we have a mountain of evidence that consciousness is, in fact, supported directly by the physical tissue of the brain. We also have an immovable mass of humanity that does not wish to face this fact and shape their lives and ethical systems upon the probably true, scientifically supported ontology that strongly, strongly suggests that this one life is all you get, that if your brain dies you die, that there is no alternative reality or superset reality where you will live in paradise or be tortured for eternity, and that there is no mysterious invisible self-aware construct that grants wishes and enforces "perfect justice" or "perfect law" or "perfect love" on a selective basis depending on whether or not one embraces a particular set of "ancient" beliefs.


Comment Re:Is the tech bubble official yet? (Score 1) 77

I'm giving up mod to add to this. Bug Jack Barron is worth the read even today, as Spinrad is a true visionary. One of my favorite books. Sort of a Rush Limbaugh in reverse, or what Stern wishes that he was. And periodically, you hear snippets of med-tech that still leave open the possibility that Spinrad's take on immortality wasn't completely wrong...


Comment Re: Cutting who? The massively inflated? (Score 1) 649

Why, exactly, is this a sentence fragment?


is a sentence, consisting of a verb in imperative form, with the understood subject 'You' (the listeners). So is "Try." So is "(You) go again." Or "(You) try again."

Oh, and since you are supposedly representing the grammar police on /., and I'm challenging your absurd statement that this is a fragment, I suppose I ought to provide you with at least some K-12 level documentation that your assertion is, in fact, absurd:

Comment Re:Getting Hyrogen from Water (Score 3, Interesting) 106

Yeah, if I were going to get hydrogen from water I would take a solar panel and hook it up to a floating platform sitting in the ocean. Underneath there would be two gold or platinum plated electrodes, one of which I would leave free and the other of which I would put in a vertical tube. On top I would have a small pump (also run by the solar cell, or maybe powered by a small wind turbine since there is usually a wind over the ocean) that compressed the hydrogen into a collection tank. That would produce hydrogen at a very, very predictable rate, fully compressed and ready to use. A small hydrogen powered boat (powered indirectly by the same solar cells) could make the rounds every week or so to replace the tanks and bring the tanks ashore for use. The rafts themselves would attract fish and de facto cool the ocean underneath. And best of all, they would produce the hydrogen for only four or five times what the electricity that produced it was worth!

Now to patent this, get a government grant, and fight the NIMBY battle with all of the boaters and fisherpeople who don't want to see the oceans and sounds scattered with floating platforms covered with solar cells and hydrogen gas tanks. I'll be rich!

Oh, wait. You mean that this idea has been around for over forty years now?

You mean that it is developed to the point where one could produce hydrogen peroxide, or release the CO2 in the ocean water and capture THAT at the same time we generate the hydrogen (for an even larger multiplier for the actual value of the electricity)? You mean that even a patent troll would have a hard time locking this one down? You mean that there really are some people, somewhere, who have heard of the second law of thermodynamics or the first law of economics (that in business, one's product has to sell for more than the cost of production)?

So what? As long as we have a government, these will not be obstacles...


Comment Re: Not surprise in the least... (Score 2) 457

Presumption of innocence is essential to a society run by laws, and it says, if you didn't get convicted by a court, you're innocent of the crime. There's not one iota of ambiguity there.

I've been following, and mostly agreeing with, your marvelous string of rant(s) on this topic, but here I must pick a very important epistemological nit.

When I drove to work today, I exceeded the legal speed limit, as I do every day. I am therefore in reality guilty of violating the laws restricting the speed I am permitted to drive my car. This guilt persists whether or not I am stopped, observed, ticketed, taken to court. It persists whether or not I am stopped, go to court, and pay a lawyer a large sum of money to have the case thrown out or to convince judge or jury that my excess speed was within some legal uncertainty associated with its measurement, whether or not there was a technical error in my citation that makes it null and void. Being guilty in reality of violating a law is quite independent of the courts, arrests, prosecutions, and verdicts. Did I commit the crime? Yes (just like pretty much every human alive driving today). Have I been "declared guilty" by a court? Absolutely not, got away with it just like almost every human alive who exceeds the speed limit today will get away with it, some of whom will exceed it by a lot. Yesterday I (accidentally, seriously) ran a red light. Didn't get caught, didn't harm anyone, but I'm absolutely guilty of doing it and am still kicking myself for letting myself get too distracted at the intersection as I could have hurt someone. Guilty, guilty, guilty.

So let's correct your statement above:

Presumption of innocence is essential to a society run by laws, and it says, if you didn't get convicted by a court, you're presumed to be innocent (in the eyes of the law). There's not one iota of ambiguity there.

NOT THE SAME as saying you ARE innocent in reality, only that as far as the law goes, you have the benefit of any doubt (and various legal protections against others acting on their own as if you were guilty). This is true even if Colonel Mustard is found in the pantry holding the wrench, is arrested without being Mirandized, confesses everything and leads the police to a wealth of absolute proof that he did it, that he planned to do it, that he is glad he did it, that he is guilty, guilty, guilty of doing it -- but all of that evidence is thrown out and consequently the jury declares him (not innocent, but) not guilty. At which point he could write a book: "I Did it in the Pantry with the Wrench, and I'm Glad", by Colonel Mustard, Esq, and could admit it on Oprah and he'd still be "not guilty" in the eyes of the law for the rest of eternity because of the double jeopardy clause.

Outside of this small but important exception, I agree with what you are saying. And it matters! Those rules that might get Col. Mustard a walk even though he is guilty as hell might protect Miss Scarlet who is intimidated into admitting that she did it in the kitchen with the knife but really was in the Library with Professor Plum. They prevent many a miscarriage of justice where a DA aggressively prosecutes somebody for political reasons on inadequate or trumped up evidence. It's not like we don't routinely convict the innocent because the person accused happens to be black or hispanic even WITH the protections we have...

That doesn't stop people from "convicting" O.J. Simpson of murder in their own minds even though he is declared "not guilty" in a trial. It doesn't stop him from (maybe) BEING guilty even though he was acquitted. It doesn't stop people from convicting Hilary Clinton and/or Donald Trump in their own minds of everything from murder down to simple child molestation and rape and (while we are obligated to presume their innocence in all legal matters including not defaming them by asserting their certain guilt in public forums, a form of "crime" that our political system tolerates SPECIFICALLY for politicians) it doesn't remove the possibility that either of them really is guilty of any number of crimes. Just not in the eyes of the law.

People with any actual wisdom ought to recognize that no matter how convinced they become of guilt due to reporting and hearsay allegations OUTSIDE of a courtroom, they don't actually have access to most of the real evidence, and they have not reliable way of assessing the truth of the evidence presented, especially in the case of politicians where "everybody lies" all of the time, both in accusing and in defending. Even under oath, it isn't uncommon to hear lies, and when one is NOT under oath, only the threat of civil suit reins in speculations and accusations (and often this is not enough). Since political slander is tolerated, politicians have to develop thick skins as they basically can't sue people for defamation even if the assertions made in a campaign are blatently false, a fact that made a joke of the last election. Even when they "can", it is a lose-lose proposition in an election and they pretty much never do.

So sure, maybe the Clintons have collectively committed murder and eat dead babies for breakfast. Perhaps Donald Trump is actually a traitor to the US because the Russians have footage of him having sex with minors and Melania is really his handler, not his wife. Perhaps they all sit around and snort cocaine together off the naked bellies of 13 year olds when they aren't in front of cameras, laughing at the naivety of the American People. But as far as the law is concerned, they have not been prosecuted and convicted of any of these hypothetical crimes. If Hilary drove to work today, I personally am pretty sure that she violated the law and really is guilty of at least that one crime, but she and I and Donald -- equally guilty in reality of speeding at least some time when we are driving -- have not been stopped and ticketed and have not gone to court and are not proven guilty of doing it and hence are presumed to be innocent of ever exceeding the speed limit while driving by as little as 0.001 mph or as much as 100 mph in the eyes of the law.


Comment Re:No real information (Score 5, Informative) 211

Well, that escalated quickly! Howbow I just reply to your first questions, because sunlight blocking isn't related nor makes much sense to me.

Let's try to make it make sense. The solar wind is driven by light pressure. Particles do not, however, follow strict radii out from the sun. They have transverse velocity components as well as radial ones. Also, they are pushed by photons from all over the face of the sun, which have different impact angles, which constantly change their transverse velocity. To put it another way, the particles driven away from the sun that will eventually hit Mars have a phase space envelope at least as large as the truncated cone formed by the surface of revolution whose boundaries are the circumference of the Sun on one end and the circumference of mars at the other.

Now consider a satellite (say) 100m in diameter. Suppose you locate it at the Lagrange point so that it is always along the line between the center of the Earth and the center of the Sun. Question: Will it dim the total sunlight received by the Earth?

Not measurably. The penumbra of this little satellite extends from its dark side to the tip of the extended cone formed by the circumference of the satellite and the circumference of the Sun. Since the Sun is basically 0.5 degrees from the Earth or the Lagrange point either way, the height of this cone is found from tan(0.5 degrees \approx 0.02 rad) \approx 0.02 rad = 100/H, or
50x100 = 5 km. So the satellite will cast a complete shadow of the sun that starts out 100 m wide right behind the satellite, then shrinks to zero around 5 km (give or take a km, I'm being lazy) . Beyond that you are in the umbra, which basically means that you are in bright sunlight from the annulus of sun surface visible around the satellite. The further out you go, the smaller the ratio of the occluded part to the directly visible part. By the time you reach the earth, the satellite is completely invisible -- the umbra is irrelevantly dimmed relative to no satellite at all, and it "covers" less of the sun's face from any viewpoint on Earth than a medium sized sunspot.

Now, if somebody were to tell you "hey, we're going to fix global warming by putting a sun shield in geosync orbit to reduce the total insolation of the Earth", your first concern would be to think about the geometry of that penumbral cone with a known cone height of roughly 5 earth radii vs a 0.5 degree Sun. Just how large would it have to be to reduce total insolation by a single whopping percent? The answer is really, really large. Even at only 5 Earth radii, which is not the distance to a Lagrange point. At the Lagrange point, really really REALLY REALLY large.

Now, is the solar wind deflection by a magnet going to be exactly like this? No, of course not. The magnetic field doesn't have a sharp cutoff -- it drops off roughly like 1/r^3 from the center of the (presumably dipole) magnet. Also, the force acting on the solar wind (charged only) particles depends on their charge and speed, the acceleration depends on their mass as well, and it has the usual nasty cross products in it so that it only really exerts a large force when particles run across the field at right angles. One would LIKE to think that a small deflection far away produced by a magnet large enough to produce a reasonable deflection a REALLY REALLY large distance away from the magnet could create a shadow as large as Mars, but it is by no means clear that this is the case, and just saying "hey, we can make really big magnets" doesn't actually help. I've got really really big magnets in my house -- ones I've pulled out of dead hard drives, that can basically hold a (small) newspaper pinned to your fridge. IF you get them within an appallingly short distance of the fridge. From a meter away, you can't feel any force at all. If you take an old CRT television or computer monitor and wave this really really strong magnet from ten or twenty meters away, it has zero visible effect on the trajectory of ultralight electrons traveling really fast. The magnetic force/field just plain drops off really quickly away from the source dipole, and isn't that strong (compared to electrostatic forces) in the first place, smaller by 1/c where c is a very large number compared to 1.

In the case of the Earth, the field can be weak only because the area, indeed the volume, occupied by the field is enormous. The entire field that does the bending is in the "near field" of the Earth itself seen as a magnetic dipole. Particles go a very long way in the field, and the field itself doesn't drop off particularly sharply with distance from the Earth. This seems unlikely to be the case for any field we can reasonably generate to shield Mars, where by "reasonably" I mean "can afford to build without indenturing a century of global GDP-scale slave labor in the form of taxation". We're talking about volumes the size of small moons with field strengths order gauss to milligauss everywhere inside, and then MAYBE the shadow would be large enough to screen Mars a very long distance away.

Even then, one has to worry about phase space and the annoying fact that magnets don't SIMPLY deflect charged particles and the fact that the solar wind has a fairly large phase space envelope as it passes the deflector. The deflector might FOCUS along one axis as it defocuses along another -- this is a common behavior of magnetic multipoles. It might even tend to conserve the net phase space that impacts Mars! At some point one has to start solving hard problems in magnetohydrodynamics.

Does this hard problem have a solution feasible at a reasonable cost? This is the only real question. The answer is, for the moment: absurdly, laughably no. We cannot even afford to GET to Mars yet at a reasonable cost, let alone undertake major terraforming engineering projects with payoffs centuries away. In the meantime, we are short all sorts of technologies -- like low cost, high temperature superconductors, thermonuclear fusion for energy, and much more -- that might be key to making it work EVENTUALLY at an affordable cost. Is it worth wasting time on right now, given that it is absurdly impossible for the foreseeable future?

Honestly, I'd say yes. And no, but more yes than no. It's a lovely problem for an undergrad physics major, maybe, or a grad student interested in that sort of thing, to play with to learn more about electrodynamics. It's not so lovely if you're planning to pay a team of professionals and devote considerable infrastructure support to them while they work on it, given that you are pretty certain that nothing they produce will be useful in anyone now alive's lifetime. In a century, when maybe -- maybe -- it is, well, why not let them do the work then? Then they'll HAVE the tools in their palette that are currently science fiction.

Same reason I think it would be silly to actually devote resources taxpayers pay for to make an engineering plan to move Europa to drop it onto Mars as phase two. Same reason I think it is silly to devote a lot of time planning for tritium mines on the moon to support thermonuclear power plants on Earth. In each case there is a "say what?" moment where you just want to bitch-slap the people who want to get paid for, or to pay for, these as if they are real feasible projects with some value in the end. It's not that these are "impossible" or "bad science" or "bad engineering". It is that pursuing them requires a sort of wilful lack of common sense and willingness to spend money that somebody, somewhere, had to earn doing real hard work of immediate value on something with no likely payoff in any forseeable future.


Comment Re:No real information (Score 2) 211

So, 1-2 Tesla peak in a device how large? A meter? Ten meters? A kilometer? (what are we going to pay for, in other words) sitting in the middle of nowhere is going to be enough to deflect off-axis charged particles by how much? Bear in mind that Mr. Sun subtends a pretty substantial arc. One such that an entire planetoid object the size of the moon barely obstructs line of sight in a tiny penumbra, sometimes, at 384K kilometers...

So just how large a region WOULD we have to cover to actually put the entire planet of Mars in its deflection penumbra? Hmmm....

If we're going to this place, why not do the same thing for Mother Earth -- put a large cloud of stuff at the lagrange point, reduce insolation, fight global warming. Price is no object! Fantasies are free! Besides, what could go wrong?


Comment Re:No real information (Score 1) 211

Hey, this is just the first step. Then we crash Europa into Mars and wait a few million years for it to cool and the water to recondense. We'll need the magnetic shield in the meantime unless Europa has enough of an iron core that the remelted Martian core turns magnetic.

Of course, we might hasten the cooling by a few hundred thousand years if we install a cloaking device at the same Lagrange point so that Mars is in its shadow.

All it takes is money, right? Unbelievably enormous amounts of money. And time, don't forget the time. Something like the entire world GDP for a few centuries. But what the heck, you're buying another whole planet, one in the same solar system, which makes this way, way more realistic a proposal than imagining travelling to a nearby star.

Well, except for the building a large enough field generator at a Lagrange point to shield a whole planet, and except for moving a good sized moon. Except for that.


Comment Re:While were at it (Score 1) 211

Not so much Jesus as King John. 36 barleycorns to the foot! How can one not love a system of weights and measures based on the grain upon which so much human happiness depends?

And hey, the mile is really decimal. Heck it STANDS for 1000. It's just a "kilo-roman-pace". Is it anyone's fault, really, that the British went with a clothyard arrow as their intermediate standard instead of something sensible, like 1 pace = 5 feet = 180 barleycorns!

Jesus, OTOH, no doubt used cubits, anticipating that in modern times we'd use qubits, which even now is a critical word to know if you play words with friends or scrabble. Thanks, Jesus!

Comment ROTFL... (Score 2) 70

... having actually looked at the problem, as opposed to saying the moral equivalent of "if pink unicorns farted fairy dust, toads could fly", what else is there to do but laugh hysterically at this proposal?

Look, if we lived in a sane universe, the problem being solved wouldn't even exist, because the government would have established a rigorous data portability standard in the first place. Given a rigorous data portability standard, data sharing across EHR's becomes a "necessary feature" instead of a malignant threat to the company that wrote the EHR who hopes that once you've invested the hundreds to thousands of hours and tens to hundreds of thousands of dollars in installing their product and porting/importing the data and training all of the staff to where they are expert enough to have learned just how their product really, really sucks, you will find all that money and time to be a large enough barrier to prevent you (physician, practice management company, hospital, whoever) from running away like a scalded llama towards absolutely anything else that might, just might, suck less.

The alternative -- that they'd actually have to continue to employ a large staff of developers who are tasked with both debugging their existing product and advancing it with feedback from users in order to actually make their users happy so that they stay with the product out of choice -- is anathema to them, because paying all of those developers and admitting errors and retraining customers as necessary dilutes their profits.

So now implementing an enormously complicated solution (one that will require a huge investment in programmers, security experts, trainers and so on and worse, will require every vendor to have hooks that permit more or less automated replication of features in other vendors' EHRs, some of which might even be proprietary or trade secrets or whatever) is suddenly going to make this particular post-apocalyptic landscape a lot better? Without laws mandating it? Without it immediately breaking as (say) Epic refuses to disclose key internals to (say) eClinicalworks or (say) Allscripts? Epic won't even willingly import HL7 data exported by other products.

So excuse me if I pause to catch my breath before resuming maniacal laughter...

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