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Comment Re:Rockets are too expensive (Score 1) 349

Sure, one built with imaginary and probably impossible materials, ignoring petty little details such as the non-equivalence of the accelerating inertial reference frames at the ground and top (not to mention all of the way up).

Here's a hint for you (and everybody else that proposes this absurdity):

a) Equatorial speed relative to center of Earth: 460 meters/second or just over 1000 mph. Around 1.35 x the speed of sound.
b) Speed at geosync orbit at R \approx 6 R_e: 6 x 460 = 2.78 km/sec.

Or if you prefer energy:
c) Total mechanical energy of 1 kg object sitting at "rest" at equator: = GMm/R_e + 1/2 m v^2 (using v from a) above): -64 MJ/kg
d) TME of same object sitting at "rest" in geosync orbit \approx -10 MJ/kg

And the worst of them all, angular momentum:
e) Total z-directed angular momentum of 1 kg on equator = mR_e v (from a): 2.9 x 10^9 kg-m^2/sec
f) Ditto at geosync (36x larger): 105 x 10^9 kg-m^2/sec

So, to lift something up from the surface to geosync, one has to:

1) Increase its tangential speed -- tangent to great circles around the axis -- by a factor of 6 as it rises.
2) Increase its mechanical energy by 50 million Joules per kilogram of payload.
3) Increase its angular momentum by well over 100 BILLION kg-m^2/sec. This is done by means of the same torque required to increase its tangential speed.

Now, let's ignore all the picky details, such as how to make a cable that can support its own weight hanging to the ground from geosync orbit -- where if we not unreasonably insist on it having a specific gravity around 1 (same as water) then we need the weight of a cable well over 5 R_e long (at least, if you want to be able to apply tangential force via the same cable) so let's START with 5 R_e -- in round numbers 5 x 6.4 x 10^6 = 32 million meters long (yes, that is million). Figuring the top tension is a bit tricky and involves an integral, but the result of the integral is that the tension at the top is the change in potential energy per kilogram times the density times the cross sectional area: GM_e\rho \Delta A (1/R_e - 1/6R_e) = 50 MJ/kg x 1000 kg/m^3 \Delta A.

This is 50 x 10^9 Newtons times the cross sectional area (in m^2), and is most easily expressed by dividing out the area to get:

Requirement: 50 GPa minimum tensile (yield!) strength

The highest tensile yield strength observed in any material (so far) is less than 5 GPa. Carbon nanotubes have a tensile strength reported as high as 63 GPa, but this is not a yield strength and could not support a sustained load, certainly not safely. So far, then, we are (honestly) well over an order of magnitude short of the required yield tensile strength required for a cable to JUST support its own weight "hanging" from the vicinity of geosync orbit. One cannot force a lower orbit USING such a cable, and higher orbits (with more cable) that are still geosync require more tension and make little sense. But hey, this is science fiction, let's PRETEND that we can make carbon nanotube cables 32 million meters long that have a yield strength of (what the hell) 500 GPa -- our 50 plus a generous margin of safety. Let's not worry about what we are going to wrap our cable around as far as pulleys go at the ends, how we will build bearings etc -- heck, that's just "engineering". Heck, anybody can design a pulley that can support a 64+ million meter long cable (looped, remember! -- oops, there goes a factor of 2 of our ten already!) that has been looped and joined "perfectly" without the slightest defect that might lower the yield strength to (say) 5 GPa and lead to catastrophe! Engineering is just drawing a picture! Why worry about what actual material you might make it out of that the cable won't cut right through (if it is thin) or crush (if it is thick) or wear out in short order as it operates?

Let's just imagine how it might WORK. After all, the whole idea is that you send a payload up on one side of the loop at the same time you send some counterweight down on the other, adding energy as needed with the bottom pulley.

Still, we have to add all of that velocity, energy, and angular momentum to the mass WHILE IT RISES! This means that the cable has to exert: a) enough vertical force on the payload mass to overcome local gravity. This comes out of the total tension budget but hey, we assumed that we could build a cable with enough surplus to be able to lift several times the weight of the cable, however thick or thin we make it. We just make the cable thick enough that the cable plus payload are WELL within this utterly imaginative, fictitious, limit. b) enough TANGENTIAL force to be able to exert the required torque on the payload as it rises! And this is a very, very serious problem, one that it will not be easy to overcome with science fiction.

For one thing, this utterly rules out "straight" cables. Even if you JUST run the loop WITHOUT payload, the rising cable will (apparently) deflect to antispinward/west in order to build up enough of a bow for the tension in the cable to be able to provide the necessary torque on the cable itself. The bigger the bow, the better the angle, but the longer the cable (and what do you do with all of that cable when you AREN'T running the loop? Hmmmm....) the greater the static tension, operating or not. The smaller the bow, the flatter the angle, the bigger the tension needed to provide the transverse acceleration/torque as well as lift the payload.

In the meantime, the descending cable is going TOO FAST for the ground. It balloons out spinward/east as it descends. The operating loop doesn't look like two vertical lines, then. It looks like two enormous arcs, stretched in opposite directions!

Lifting the mass has two more really interesting effects. One is that the cable pulls the geosync end DOWN relative to static tension equilibrium when you load it. The loops have to come from somewhere, and if the station stretches the cables "tight" at equilibrium, the opening of the loops has to reduce the vertical span of the loop, period. Moving it down moves it out of geostationary stasis -- the station ITSELF starts to deflect to spinward as it is going too fast for a lower circle at constant angular velocity (there are lovely demonstrations of this involving coin spirals in shopping malls or figure skaters). As the mass rises, though, it pulls backwards on the station. It is basically undergoing a "slow" inelastic collision with the station! It started with the wrong angular momentum (too low, from Earth's surface). The Earth's surface cannot ADD angular momentum to the space station -- it moved forward because it was being conserved when we turned on the loop and it moved to a lower circle! But as the particle rises, it really DOES reduce the angular momentum of the space station as it increases the angular momentum of the payload. In fact, overall, it is sort of like you fired the payload at the station in the direction opposite its motion at 2 km/sec, and the mass then collides with the station and sticks!

It doesn't happen that fast and it may not release heat during the collision (assuming our motors do their work) but as far as angular momentum is concerned, that's what happens. The rising mass pulls antispinwards on BOTH the mass AND the space station, but the space station is not fixed.

At the end of the day, if the station was in geosynchronous static tension equilibrium before you sent up your payload, after you've sent an unbalanced load up it is not, basically because strings cannot exert any shear stress on the space station and can exert tangential forces on the mass only by pulling the station down to a different radius. And this is all in the quasi-static limit, ignoring the WAVES that any loaded motion would induce on the loop and just what happens to the slack that develops in the loop.

In the end, you have to add energy and angular momentum back to the station plus platform in order to re-achieve geosync orbit. To do that, you are right back to using rockets (or still more science fiction).

Let's face it. The "space elevator" concept is deeply flawed, IN ADDITION to the fact that it is currently literally impossible to build from the material science point of view. We haven't even touched on the problems building an attractive trillion dollar target in the sky that a laser or physical projectile can trivially destroy by just creating defects in the cable, in the case of a laser quite possibly from hundreds of miles away or elsewhere in orbit, or its vulnerability to space junk all along its considerable length. Stories that utilize it always seem to forget the coriolis (pseudo) "force" and the problems with inducing waves on rotating loops where one end of the loop is free floating in an either system rotating (of necessity) with a constant angular velocity. If we're going to push sci-fi, let's contemplate land-based electromagnetic mass drivers (which are in principle feasible, if still pretty absurd in cost and engineering "details").

Comment Re:Jesus saves (Score 1) 207

You mean to say Pink Unicorns COULD exist -- if we build them -- and I agree. And they could exist even if we don't. For a long time, Europeans thought that there were no black swans because they'd never seen any. They were wrong -- they just hadn't looked in the right place. Now we would say that there are no paisley dayglo multicolored swans because we've looked everywhere that one could reasonably find swans, we've catalogued swan DNA, we understand the process of evolution that gave rise to swans and the artistic human process that produces paisley and concluded that they are pretty much orthogonal, and concluded that it is very, very,.... very unlikely that there are swans whose natural feather color pattern is a riotous mix of dayglo colors arranged in perfect swirls against (say) a dark blue or violet background. But not impossible. It is likely that SOME DNA pattern, possibly intercalated from peacock DNA and then hacked a bit, could produce an animal with 99.99% Swan DNA -- morphologically a swan -- that naturally expresses paisley on its feathers. Maybe even an animal that could breed true with other swans.

As for Shetland Ponies with horns -- it's a lot easier to just drill their skulls under anesthetic and install a screw-in socket that will accept a spiral horn. Or an iron plate that one can attach a rare-earth magnetic horn to without any break in the skin. Pink dye is a lot easier than recombinant DNA. One could do that "tomorrow", if one didn't have to contend with those silly animal cruelty laws, and it isn't clear that they'd protect the pony even from this insult if the result didn't really hurt them...

Now try to do the same thing with God(s). That's why I (sarcastically) suggest that they aren't really even conceivable. Humans imagine God by:

a) Taking a purely human concept, such as that of a Human Despot (Lord, King, Emperor). They say to themselves "Hey, Lords are pretty powerful, but Kings are more powerful. And Emperors are even more powerful -- Kings of Kings as it were. I therefore can understand the sequence from me = not powerful, to my feudal lord = more powerful, to my king = still more powerful, to my emperor = most powerful in the worldly realm as an ordinal set in "power".

b) Adding other concepts -- artist/creators from me (fingerpainter) to a high school art instructor, to a modern artists who is well enough known to get shows in museums and galleries, to the Renoir's, Da Vinci's, Picasso's of the world -- an ordinal set in "creativity"; dumb as a post (e.g. farm animals), to a high school graduate, to a college graduate, to brilliant mathematicians and physicists e.g. Einstein or Ramanujan -- an ordinal set in "knowledge" or "reasoning ability".

c) Extrapolating the set. Suppose we imagine a being that is more powerful than any other being as the limit of this ordinal set. Same being is also more creative, more knowledgeable, more intelligent, more compassionate, more loving... name any positive ordinal quality, imagine a being with that quality, extrapolate to a hypothesized most whatever of that quality, possessing perfection in that quality, all with conjunctions, so that they are the most loving and most just. Don't worry too much if the two qualities are consistent, that in some sense one cannot be the most just (giving people what they deserve) and the most loving (NOT giving people what they deserve but rather what they want) -- just keep your thoughts vague enough that they don't have to confront any contradictions and imagine each "most" quality one at a time.

d) The result is God. God is bigger than the biggest, hence larger than the Universe. He is smarter than the smartest, so he knows EVERYTHING. He's more creative than the most creative, indeed anything that exists was created by God; even my fingerpaintings are really God's fingerpaintings, planned out in complete detail to the subatomic scale long before I was born. He's perfectly just (and sends sinners to hell and the virtuous to heaven) and perfectly loving (and forgives everybody their sins) and manages BOTH even though we live in a world -- that He created with perfect knowledge of how it was going to come out and hence is responsible for every detail of the actions of saints and sinners alike -- where sin is often rewarded and virtue often punished, promising to punish some people for ETERNITY with truly HORRIFIC punishments and reward others for ETERNITY with truly SUBLIME pleasures while supposedly loving them all equally and wishing that they would not do that which they were created specifically to do by the only "free" agency in such a created Universe, the Creator. A mass of self-contradictions, in other worlds, both physical (violating observational science as a matter of course), logical (being bigger than the Universe contradicts the meaning of the term "Universe"), and moral (I love you but I'm going torture you forever because you did exactly what I predestined you to do when I created the Universe).

It's a bit hard to build that little pony, with or without the horn. And for the record, human kings are a lousy metaphor for good, period, let along perfect goodness and compassion.

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Comment Re:Richard Feynman was an athiest (Score 2) 207

Thankfully, God has made a way of escape through Jesus Christ, His Son (John 3:16). The choice is yours alone to make. Do you really believe that the Creator is âoeThe God who wasn't thereâ as atheists allege. Every watch has a maker, and I assure you that the universe has a Maker as well. It is not only improbable; but impossible that this universe just happened, let alone that it evolved from some chaotic explosion... A BIG BANG! Please, what a joke! Chaos never leads to order. Order can only come from careful planning and meticulous precision, which God has certainly accomplished. It is man that steals, kills, and destroys as Satan wants them too (John 10:10).

So let's get this straight. The Universe is a big, complex place that doesn't show the slightest evidence of actual design or intervention. You assert without proof that it must have been created, even though all the laws of nature based on observation are CONSERVATION LAWS that suggest that NOTHING has ever been created in the history of the Universe itself. Everything that you think of as being the "creation" of something is just preexisting stuff moving around. You have never observed one single thing actually being created -- or destroyed -- only the changing of forms of that which already is. In some very deep sense, your error comes from this -- you misinterpret the actual, literal meaning of the verb "to create" as it applies to every single actual thing you've ever seen or experienced. A potter does not "create" a pot, not in the sense you are using the term to refer to an act of a hypothesized deity. A potter reshapes preexisting clay to -- very temporarily, on a cosmic scale -- have the form of a pot. You are conflating your experience with pots -- one day not there, another day there -- to misapply common language to Universes, forgetting that you've never seen anything actually come out of nothing and have no reason whatsoever to think that it ever has.

This big, complex place, then, is supposed to be like that pot, something shaped by some intelligent hand. You assert it because (implicitly) nothing can have complex shapes unless intelligence produces them. If we ignore for the moment the fact that every snowflake that has ever existed or will ever exist refutes you -- complexity arising out of thoughtless matter interacting with remarkably simple rules -- and grant the premise, then you immediately encounter a consistency issue and problem with recursion. The potter is without doubt more "complex" than the pot he creates. But that (according to you) is why we cannot view the pot as having been produced by a natural process, or the potter as being produced by a natural process. The Universe itself, with all of its apparently natural processes is really really complex, and complex things are NEVER to be found without being put there by intelligence that is even more complex.

If we ignore the long string of unprovable, unfounded assumptions (in most cases, assumptions that are easily refuted by actual examples in physics, chemistry, even formal mathematics) we find that your conclusion -- that God must exist to have been the greater intelligence that designed the Universe that -- through the pure unfolding of natural law -- evolved the potter that -- following the inevitable path of his life determined by those same natural laws -- appeared to "design" a pot that he then assembled out of some stuff that he dug out of the ground which was eventually sold, used for a dozen years, broke, and was then ground over centuries back into dust once again -- is inconsistent. God is more complex than the world, complexity only can happen through intelligent design, therefore God was intelligently designed, therefore God was designed and "created" by a still more complex God and isn't really God. There is no terminus to the chain thus induced -- any God you postulate must always have been "created" by a still smarter, still more powerful and more intelligent God and no God, any any level, can be certain that they were not! The God of any n+1 level in the chain could be invisible to the God of the n level in the chain, just as "God" in our existence is quite invisible, without a shred of actual evidence or experience supporting their necessary existence.

Once you open the door to believing in invisible things without actual evidence, where does it all end? Starting with belief in a contradiction -- or just a false assertion -- one can then "logically" prove just about anything. To quote Voltaire (since you like quoting people, let's quote somebody with a brain, shall we?) -- "It is a small step from believing an absurdity to committing an atrocity."

I ask you, sir -- are you not silently advocating atrocity in your absurd statements? Are you not openly inviting the persecution of those people you disagree with, with movie directors, entertainers, homosexuals, communists? Quite aside from the fact that Jesus and his disciples advocated what amounts to communism (if we are to take the patently false and openly absurd books in the New Testament seriously) and spoke out quite seriously against judging others, you seem to have set yourself up as a judge, qualified to know the mind of the God you imagine, and in his name you are giving support and encouragement to those that would commit violence against those you fear or dislike or merely disagree with. And so it ever is, when men convince themselves that black is white, that up is down, that it is perfectly reasonable to think that somebody rose from the dead 2000 years ago on the basis of hearsay evidence passed down by a religious cult that made it big but totally unreasonable if anybody were to make similar claims today.

Which is a shame, because today we really do make the blind see, we make the deaf hear, we make the cripples walk again, and sometimes we even raise the very recently, technically, dead (by the standards of antiquity, anyway). We do this not by prayer, belief, of the direct intervention of an invisible deity bending the laws of space and time on your personal behalf, breaking the very laws you assert that they made. We do it by means of science. We've figured out how things work, what's wrong, and how to fix it. No prayer or belief required. Gravity works for you the same as it works for me, and not even Jesus was tempted to violate the law of gravity, if you believe in the Jesus myths.

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Comment Re:Jesus saves (Score 5, Funny) 207

There are none who do not believe in Pink Unicorns! How can any man say, who has not travelled to the farthest end of the Universe, that Pink Unicorns do not exist? Indeed, anybody who says so secretly is claiming to BE a Pink Unicorn. Pink Unicorns hate fags and commies so you -- I'm talking to you, you apostatic Pink Unicorn believer wearing the halloween costume -- need to pass draconian laws punishing commies and let us arrest fags and send them against their will to a special school that will teach them to find only members of the opposite sex attractive, and then only within the bounds of holy matrimony. I'm talking about you, Robert De Niro and you, Billy Joel! You claim not to believe in the Pink One's Perfect Horn, but deep in your heart you have seen its Cornute Majesty as the twist in every spiral galaxy, especially those that radiate high in the Pink part of the spectrum.

DON'T BLAME ME, you anunicornists, if the great Pink Unicorn shows up one day and impales you on its Horn of Perfect Justice! It could happen! Seriously! You haven't BEEN to Alpha Centauri -- it could be liberally populated with Pink Unicorns for all you know! I have had a Holy Vision of Pink, and I Know! So sayeth the prophets, and everybody knows that people who wrote stuff down LONG AGO are always right and never made mistakes! Only that liberal commie activity known as "science" makes mistakes -- imagine, insisting on POSITIVE evidence for the existence of Pink Unicorns when the Holy Fathers among the ancients speak of "walking with the Unicorn" and tell of the many miracles performed by the Pinkest of them all. What more evidence do you need?

Oh, and by the way, pay no attention to the deluded fools in that cult over there who claim that Unicorns are not Pink, they are really Blue. Or that group -- Purple Dinosaurs (that walked with men back before the flood) are clearly right up there with Winkie-Tink, thinly disguised Faggery intended to corrupt the morals of our children and distract them from Pink! Besides, they have no evidence to back their claim, as clearly THEIR ancient prophets were just smelly old men who are lying to you to corrupt you. But the one true Pink Unicorn knows all and sees all, peering out from behind every rock and stone in the Universe, and...

What's that? Take your hands off of me, sir! I protest! Well of course I stopped taking that medicine! It was distracting me from my holy duty! I could no longer see Pink when I closed my eyes, my mortal body was in danger of being Holed and the prophets say that sinners who turn their back on the Unicorn will be trampled under hoof for all eternity! Let me go!

I will not be silenced! No! Don't put me in there! No! No! Not the needle! The TRUTH will soon be known! BEWARE, you foul, white jacketed sinners, the Unicorn that comes to trample you and everyone you love in the ni

Comment Re:Copenhagen Interpretation (Score 1) 82

OK, I'll try again. YOU DON'T. All you see is electrons being "consumed" as they hit the screen, forming the interference pattern.

If you DO look for them as they pass through the slits -- where one can do this without "consuming" them by e.g. putting a conducting loop around the slit that will experience a voltage pulse as the electron passes THROUGH it or by illuminating the volume right behind one of the slits with intense light that can scatter off of the moving electron and hence detect the slit the electron passed though -- then the interference pattern goes away.

This is a fundamental sort of "goes away". It isn't just that we gave a small extra push to the electron, as in principle you can CLASSICALLY make the detection so weak that it wouldn't affect the classical trajectory. It is that the detection itself shifts the PHASE of the electron and hence destroys its coherence with the electron(s) passing through the other slit, so there is no longer any interference.

Also, you can read:

https://en.wikipedia.org/wiki/...

which both walks through all of this and provides you with references to at least some of the actual experiments that verify it.

Comment Re:Copenhagen Interpretation (Score 1) 82

It is. The point is that if you measure which slit it passes through, the interference pattern that implies that it passed through both AS A WAVE, not a particle, disappears. The rule for this sort of thing is that if you measure wavelike properties, you don't get a definite particle position/state. If you measure a definite particle position/state, you don't get wavelike behavior any more. This is called complementarity and is the basis of the uncertainty principle. Electrons and photons alike behave the same way. Even at very low intensities where you can effectively observe single photons or electrons AT THE DETECTOR, if you don't look to see which slit they go through you get interference, implying that the electron passed through both as a wave (function). If you do look and measure the slit the photon or electron passes through, no more interference pattern, no more waves.

The electron in some sense isn't in two places at once -- it is "everywhere" at once, but with a low probability, if it has a very well defined momentum and hence wavelength. If you measure it or confine it to some specific location, you do so at the irreducible expense of having a well-defined momentum (and hence wavelength).

I'm actually teaching this stuff right now at the most elementary level. There aren't a lot of good intro level books on it, but I'm using Harris's "Modern Physics", which is at least pretty readable and has some of the real math in it. Beyond intro modern physics books, you can try Wikipedia (often has surprisingly good articles on this sort of thing) or a real quantum textbook. Or two. Or three or four. It takes years to not quite understand quantum mechanics, and an important step along the way is to UNlearn all of the nonsense you "learned" about it in English statements and to concentrate on the consistent mathematical and conceptual formulation of the theory.

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Comment Re:Copenhagen Interpretation (Score 1) 82

Hey, somebody had to do it. Using English with embedded classical logic to describe quantum phenomena is a waste of time. And even most physicists have never read Schwinger or studied the Nakajima-Zwanzig equation and hence have little idea of how to formally obtain the classical measurement projection in an open system interacting with a classically described statistical bath when the combined closed system is in a stationary state and has no probabilities at all. And then there is relativity and time reversal invariance.

I'm just sitting here, wondering if the back of the envelope computation is dead. When did we get to the point where we could resolve 30+ orders of magnitude effects in the lab? We haven't even -- as far as I know -- experimentally verified whether normal matter gravitation attracts or repels antimatter, which seems like it would be a pretty important first step in building a QFT with gravity or GR, but even that seems beyond us so far.

rgb

Comment Re:"Helping our galaxy on its journey" (Score 3, Informative) 149

Mod +1. This is the second or third time I've seen summaries of the press announcement, and the first time it has been even obliquely acknowledged that the so called "repeller" is nothing more than a localized lack of PULL, not any sort of actual gravitational "push". -1 to the article itself for being misleading bullshit and creating a "dipole" like an electron and an electron hole create a "dipole" in a uniform neutral metal, no more.

Surely there is nothing surprising about this. People have been doing cosmological simulations for a LONG time with a large number of pointlike objects interacting with GMm/r^2 attractive forces but to simulate galactic evolution and universal evolution from the big bang. The interesting point being that in the center of a uniform mass distribution, there is no net force but nevertheless 1/r^2 forces with any kind of inhomogeneity in the underlying free mass distribution tends to accrete in some places and abandon others, especially if it can inelastically interact and clump together into bound subsystems. This must have been seen in simulations pretty much every time, and should come as no surprise in nature.

Comment Re: I feel that lone sysadmin's pain (Score 5, Interesting) 356

Having used the "sweet rm" trick back in the 80's somewhere (with much more limited space, and a cron FIFO groomer) it also doesn't protect you from a wide variety of file corruption issues and overwrites. Remove a file, recreate it, remove it again? Delete two files from different parts of your tree -- e.g. README -- that have the same name? Original file gone (unless you don't just alias rm, you write a very complicated script). If you run out of space and have an alias/script like "flush" to take out the trash and make room for more, it just moves the problem one notch downstream.

With that said, it did save my ass a few times. Then I learned personal discipline, started using version control (SCCS at the time, IIRC) onto a reliable server to not just back up any files of any importance I create but to save reversible strings of revisions back to the Egg, and stopped using my reversible rm altogether after one or two of the disasters it still leaves open.

Moral: Version control with frequent checkins usually leaves your working image itself on your working machine. Keeping the repository on a different machine is already one level of redundancy. Keeping it on a server class machine in a tier 1 or tier 2 facility with reliable, regular backups and RAIDed disk is suddenly very, very, very reliable. As the current incident shows, not perfectly reliable. Human error, multiple disk failures in an array, nuclear war, internal malice or incompetence or just plain accident can still cause data loss, but in this case what is being reported isn't disaster -- they had 6 hour backups! Even though I'm sure there will be some folks who are inconvenienced, MOST of the users will still have usable, current working copies and be out anywhere from zero to a few hours of work. I've been on both sides of the sysadmin aisle in data loss server crashes, and -- they happen. Wise users use a belt AND suspenders to the extent possible lest they find their pants gathered around their ankles one day...

Comment Re:The speed of light isn't constant (Score 1) 139

Because of dispersion (different frequencies) inside dynamically polarizable materials. Not in a vacuum. In a vacuum, the speed of light is predicted to be -- the speed of light.

Light can be bent by gravitational fields, but the thought is that the bent trajectories are geodesics in bent spacetime, not actual lenses which bend light by slowing it down due to the susceptibility of space.

Comment Re: God created the moon (Score 1) 140

OK, have to step in here. The map is not the territory, and the idea of a thing is not a thing. If you are saying "God is not a thing, it is an idea" I'd agree with you. But ideas are not in any necessary one-to-one correspondence with the Universe of "things that actually exist", and ideas to the very best of our experience a) are highly complex phenomena contingent on all sorts of material stuff and do not just float around like quantum particles that permeate and surround the Universe (h/t to Terry Pratchett); b) cannot and do not "create" anything, ever. In fact there is no evidence that anything, ever, has been created. The laws of physics are all pretty much constrained by conservation principles (consistent with observation) that state that nothing is ever created, it is all just existing stuff changing form and moving around.

The second thing I'd object to is the idea that anyone at all can "reason" about God in a meaningful or useful way. The first step in such a reasoning process is to choose one's premises, or axioms, or postulates -- the basis for one's eventual "consistent" conclusions. This is precisely the same whether one is reasoning about mathematics, the Universe of stuff that actually exists, or the enormous metaphysical space of pure speculation -- reasoning about pink unicorns, trying to decide if Santa likes hot chocolate with or without a splash of peppermint Schnapps on Christmas eve, how many angels can dance on the head of a standard shirt-packing pin. The premises themselves cannot be proven -- they are PREMISES -- so all reasoning contingent upon the premises is Bullshit in the precise sense that there is (as noted) no necessary one-to-one correspondence with the pattern of consistent results on derives with the very best of intentions and the real world.

The second step in USEFUL reasoning is to seek out objective correspondences between those contingent results AND the real world. To the extent that they are discovered to exist, we strengthen our degree of belief in the conclusions, and by Bayesian reasoning, the premises that led to the conclusions in good correspondence. To the extent that they are contradicted, we at least weaken our degree of belief in the conclusions, and again by inheritance in the premises that led to the contradiction. This is a slight oversimplification as multiple premises contribute to most nontrivial conclusions and it is not necessarily clear which one(s) fail, but there is no doubt that REASON requires reduction of belief in the conclusion itself rather than amplification when there is either no evidence supporting it (but there is evidence supporting competing ideas and arguments) or if the evidence contradicts it.

And here's the rub. The very first step about any reasoning process about God has to begin with the pure assertion that God exists. This is because we have no direct and usable sensory data, no direct "experience" of God the way we have experience of toast, or things falling down when dropped. We have built powerful apparatus that extends the range and sensitivity of our senses and none of it reveals God. We have conducted careful statistical analyses of human experience contingent on things like belief and prayer and behavior and -- outside of obvious stuff that behaving "well" is more likely to make one happy than being a butt in human society -- no phenomena or statistical anomalies are observed that require supernatural explanation. One cannot predict one single thing about the world and how it behaves or outcomes based on religious belief or the asserted premise "God exists for some useful meaning of the word `exists'". To paraphrase, the rain falls on Saint and Sinner alike.

What we CAN do is examine the consequences of BELIEF ITSELF. Believing in something has an enormous impact on human existence. In a sense, our society (or societies!) are defined by their beliefs, their memetic structure, their history, their evolution -- including religious beliefs. Religious beliefs make an enormous set of untestable, empirically unsupportable assertions, assertions that are blatently internally inconsistent. Contradictions abound. One can, as everybody SHOULD know, "reason" your way to any conclusion you like from contradictory premises, so it comes as no real surprise that humans are constantly manipulated and manipulate others on the basis of these absurd contradictory beliefs. Since all major religions assert a special exception for ordinary reasoning processes when it comes to reasoning about the religions themselves as a necessary step in getting people to continue to believe in the absurdity, they persist, and humans who accept them make monumentally poor decisions, choices that they would never make if they were actually reasoning correctly and optimally in and about the real world.

Religion is arguably the number one killer of humans active on the planet at this very moment. It is directly responsible for some of the largest and longest running armed conflicts in our mutual history. It enslaves and distorts the judgment of some 3/4 of the human population -- literally enslaves perhaps a billion women in the Abrahamic faiths. It causes the redirection of a huge fraction of the global production of the human species into the "service" of the priesthood(s) of the various religions, who spend most of it supporting themselves without an actual job that actually produces something useful, like toast or Schnapps flavored hot chocolate. The religions that persist after a brutal memetic evolution process involving world conquest and domination at the point of a sword are almost without exception socially engineered at this point to make the poor and disadvantaged human content enough with their lot to avoid revolution against the prevailing powers that keep them poor and disadvantaged by promising them eternal pleasures in an imaginary afterlife if only they behave themselves and are good little proles in this one.

Sure, this too is an oversimplification -- some people, in some religions, also do some good things. But that is more because they are good people than because the religion itself is good, and good or not it isn't likely to be TRUE. Reasoning from FALSE premises isn't all that great a thing to do, or to base a sane society on.

Comment Finally! A Real Science article on /.! (Score 1) 279

Just kidding. Not so much.

Personally, I think we evolved without it when we took to walking upright. A penis bone would have kept all male penises pointing up at the angle of optimum intromission. This would have forced all males to urinate in long rainbow arcs that got piss all over the place in a highly conspicuous way and would have made the penis, sticking out and up right up front, highly vulnerable to all sorts of weapons as tribal man fought one another. Hard to tuck the junk back and out of risk when you are standing if you have to break a bone to do it. Humans are also enormously mutually fertile (roughly 10% of the time) and live a very long time, so long intromission, short intromission, neither one is going to be effective at ensuring "monogamy" and of course arguing that human culture is monogamous even today is pretty much to make a RELIGIOUS argument as the best that can be supported empirically is some mix of serial monogamy, serial polygamy, serial polyandry, and just plain fucking around with a smattering of true "lifetime exclusive" monogamy mixed in, maybe 10 or 20%. Swans may mate for life, but humans are lucky if they mate for dinner, if one follows overt statistics, and even that is probably driven more by religious memes than by "nature". The memes are rather at war with the genes, and different cultures follow different patterns for optimizing mate selection worldwide.

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