Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?

Comment: Re:Why is this dribble on the front page? (Score 2) 441

by rgbatduke (#49798433) Attached to: Creationists Manipulating Search Results

We wouldn't know. We do know that perceptual errors, emotional disturbances, and the rest are possible.

You are simply saying that we cannot disprove God, that absence of evidence is not conclusive evidence of absence. Sure. But so what? We can go down an enormously -- actually uncountably infinite -- list of propositions for which we have no evidence. If we are sane, we do not grab arbitrary entries from this list and promote them to plausible beliefs, no matter how pretty a story they make.

Your argument is, of course, ancient and has a name. You are arguing for a God of the Gaps. As human knowledge has expanded, thing after thing that was attributed to God in ancient scripture has been shown to have natural causes. Furthermore, "natural causes" have been shown to have a rigorous, inviolable consistency so much so that when we look hard for cases where our existing laws fail, or where there are still pernicious inconsistencies that suggest that they are not quite right and will require future revision.

Since all of the "easy" gaps have been plugged, you are stuck following this chain:

Laws of Nature (microscopic nuclear + E&M and QFT) -> nuclei and nucleons
Laws of Nature (E&M/QED) -> atoms and molecules (Chemistry!)
Chemistry -> Inorganic and Organic chemistry
Organic chemistry + classical E&M and mechanics -> biochemistry and biophysics
Biochemistry and biophysics -> evolutionary biochemistry, neurophysiology etc (Biology)
Biology -> neuropsychology, anthropology, medicine, (Psychology!)
Psychology & information theory & mathematics -> Intelligence and cognition, Artificial intelligence, etc.

At this point, you take the fact that the science is incomplete to extend the quite correct observation that we don't understand all aspects of human consciousness (yet!) in full detail as a "gap" in which you can insert God. Consciousness is only possible with God, God can communicate with humans by directly manipulating microscopic physics, chemistry, biology, psychology laws in ways that directly violate the second law of thermodynamics, and so on. Forget whether or not there is any good reason to think that this is true. Forget the fact that we have an entire, consistent, empirically validated chain of physical law and reasoning stretching from the microscopic to the macroscopic. If you hear voices in your head, it could be God instead of (for example) your right brain talking to your left brain or some other perfectly natural thing. Hence in your mind, there is a reason to believe, and furthermore to invent a whole new "logic" to explain the fact that your conclusions can be held independent of the mere common sense that leads to the development of consistent science.

Obviously -- seriously -- you are mistaken. What you are doing is called the "Mind Projection Fallacy". To quote wikipedia:

Once one has grasped the idea, one sees the Mind Projection Fallacy everywhere; what we have been taught as deep wisdom, is stripped of its pretensions and seen to be instead a foolish non sequitur. The error occurs in two complementary forms, which we might indicate thus: (A) (My own imagination) (Real property of Nature), [or] (B) (My own ignorance) (Nature is indeterminate)

Welcome to B, with an admixture of A. Our ignorance is not an excuse for assuming that Nature is indeterminate and there is room for e.g. violations of the first or second laws of thermodynamics at the whim of a Deity, and your imagination of God filling the gaps in our knowledge is neither evidence nor (worse!) certainty that that which you imagine is a real thing.


Comment: Sure, only pick the prizes for the race carefully. (Score 1) 267

For example, China and the US could have a bet -- loser's premier/president has to sing the national anthem of the other on international television. Or they could bet a really nice dinner in Paris. Or maybe they could bet, I dunno, world domination and possession of all lunar resources in perpetuity. I know which one The Brain would pick...

Comment: Re:Why is this dribble on the front page? (Score 1) 441

by rgbatduke (#49787675) Attached to: Creationists Manipulating Search Results

His noodleness won't need to forgive me of anything. I'm perfectly aware of the correlation between piracy and global warming, and what more evidence does one need? And who can deny the reality of fettucini, especially when made with loving hands?

Unless, of course, one is inclined to think of J. R. "Bob" Dobbs as being the incarnation of deity. Or Xenu. Or Krishna. Or Odin. Or Vishnu. Or Allah. Or Jesus. Or Zeus. Or Quetzacoatl. Or Yahweh. Or...

His divine noodleosity makes as much sense as any of the named possibilities, and serves well to emphasize that with the exception of mavericks like Benjamin Franklin who supposedly believed a little bit in "everything" and are N-n for some value of n, everybody is an N-1 atheist except for real atheists who are N.

Comment: Re:Why is this dribble on the front page? (Score 3, Insightful) 441

by rgbatduke (#49781367) Attached to: Creationists Manipulating Search Results

Most atheists/agnostics at this point will insist upon their own definitions. It becomes a semantic argument, and if you insist upon your own definitions, you have effectively erected a straw man. Perhaps this is not the best approach.

I think you have it exactly backwards. The meaning of omniscient and omnipotent are perfectly clear and are contained in any dictionary. As you say above, every religion, including the many sects and branches of "Christianity", faced with the obvious fact that their god(s) is/are not possessing of either quality in its true formal meaning, adopt some weaker definition, so that God isn't all-knowing (the literal meaning of omniscient) or all-powerful (the literal meaning of omnipotent) or all-good (omnibenevolent) or ubiquitous (omnipresent) or "perfect" or any other infinite quality that would get them in the kind of obvious trouble any sort of infinite attribute is likely to lead to. At the same time, they have to assert that this really really big, mostly knowing, somewhat powerful, occasionally incredibly cruel being was knowing enough and powerful enough to be the proximate cause of the entire visible Universe as well as any still unseen invisible parts, which he (masculine gender usually assigned) created out of nothing, because otherwise most of us wouldn't consider even a really big, really smart, mostly good space alien to be a god, we'd consider them to be somebody like us, living in time's stream with every moment mostly a surprise because our finite information capacity is "infinitely" smaller than the information content of the Universe.

So yes, I've learned the hard way that there is little point in discussing Christianity in a reasoned way with a Christian. The fact that they are still a Christian is de facto proof that they have already arrived at a state of cognitive dissonance wherein all the myriad contradictions in (e.g.) the Bible itself or between bald assertions in the Bible (old and/or new testaments and/or apocrypha) and mere reality are smoothly elided and rationalized by doing what you're doing, bending the clear definitions of the simple terms used to describe God with a capital G.

One has to do this, because otherwise the problem of theodicy is a crushing burden for any religion claiming any significant fraction of the "omni"-properties conjoined with the assertion that god is good. One has to literally turn off one's common sense to believe that a being exists that on the one hand created the entire Universe out of nothing in some sort of state of knowledge of its future course (in most of the Bible, it is pretty clear that this state is supposed to be perfect knowledge beginning to end, alpha and omega and predestination and all that) but who created the Universe filled with evil as experienced by humans (undeniable) but was at the same time all-good and who runs things so that one can never detect Its existence because the visible Universe appears to follow rigorous rules that are never violated and that are utterly indifferent to human suffering.

That's actually the more interesting aspect of Chrisitianity in particular. Since Jesus is advanced as being God and Human and all-compassionate and perfectly good, and since the New Testament is full of direct quotes of Jesus asserting that he can do literally anything (and so can all of us) just by "having faith" and wishing it into being, Christians have to engage in the most incredible mental distortions to explain the mind of God/Jesus in such a way that there is room for the existence of human suffering on Earth and Hell for unbelievers and all of the other madness while the principle parties remain hidden.

So next time somebody dies slowly of cancer, next time a baby is born in innocence with the terrible affliction of Down's syndrome, the next time a small child dies of starvation or from malaria or from being bitten by a snake, the next time you are directly confronted with the cognitive dissonance between your belief and reality, instead of doing what you usually do, instead of participating in the ritual designed to help you elide the contradictions and consider the horror part of the "mystery" of God, why not confront them?

Down's syndrome is perfectly understandable as a trisomy of a chromosome that happens for no "reason" other than the accidents of imperfect processes that are completely indifferent to the outcome and proceed according to equally indifferent natural law. It is impossible to understand in the context of any being powerful enough to prevent the accident, compassionate enough to wish for such cruel accidents to never occur to a sentient being, benevolent enough to repair any such accident after it happens if you somehow want to assert that they "couldn't" do it before (but were still God). The fact that Down's syndrome and the full host of afflictions that can easily be explained by the principles of physics in an indifferent universe where statistical mechanics describes the progression of entropy isn't a mystery, it is an utter lack of evidence for anything mysterious. It is humans who make up all of the mystery because of their egocentric desire to be the center of something's attention rather than a rather unlikely and transient pile of thinking stardust with a strictly limited shelf life.


Comment: Re:Why is this dribble on the front page? (Score 2) 441

by rgbatduke (#49779921) Attached to: Creationists Manipulating Search Results

No, I got the bit about fiction. I just finished reading recent science fiction that utilizes very similar plot lines in several distinct stories, that's all. Even in the movie "Merlin", Mab's existence was contingent on belief. I think American Gods by Neil Gaiman is pretty much precisely that as well. To quote from its Wikipedia page:

The central premise of the novel is that gods and mythological creatures exist because people believe in them (a form of thoughtform).

So as I said, yes, you are quite right, it is (or can be, a premise for a good science fiction/fantasy novel. And has been, several times. And quite a number of bad ones as well. It's a very interesting philosophical/ontological problem -- does belief precede or follow existence?

Personally, as a physicist, I have to say that correct/best belief (as opposed to fantasy) follows existence, and ultimately is empirically founded on it. Religion is the other kind, the one where there is plenty of belief but no solid evidence for the existence of the objects of the belief.

To paraphrase Austin Power, I may believe in a gold plated potty but that doesn't mean that one exists, not even in an infinite Universe where it is possible that one exists.

Or, to toss in a reference to Russell, it is possible that there is a silver teapot floating around in an orbit around Saturn. I might, if I were un-sane enough, believe in such a teapot, and write out an entire mythology based on the teapot and how it got there and what its existence means for the Universe in general. But even if I convinced every human alive on Earth that I must be right, that as an authority on all matters concerning the Sacred Silver Teapot my word on this cannot be doubted, not even the deep and profound belief of every person in the world has the slightest chance of either creating the teapot from nothing but the belief itself or increasing the probability that the teapot exists from a number so close to zero that their kids go to the same school, noise from parties in zero's yard keep the probability up at night, they argue about who is going to trim the hedge and who is providing the beer...


Comment: Re:root knows all (Score 1) 441

by rgbatduke (#49779871) Attached to: Creationists Manipulating Search Results

So you mean, God's omniscience is, well, sort of like not being omniscient at all. I mean I can look at the Universe and get all of the information I "need". Well, at least I can get all of the information I need if I'm omniscient enough to know what information I need before I look at it, or if I have moderate needs.

Next you'll be telling me It didn't really create the Universe, it just sort of nudged already existing stuff around, sort of like using a debugger to rewrite existing code. And that It doesn't really control the Universe, it just hacks it a bit so it does some of the stuff that it wants.

Then I'll be telling you:

a) sort of like, not being God at all, isn't it?

b) and besides, there is no evidence that any of these assertions are true, or consistent.

In the end, if God has nonzero information entropy, then It is not God. If it has zero entropy, it has no Choice (and is not God, not in any way that matters). The Universe has zero entropy already.

Assertions of God are almost invariably made without any appreciation for the mathematical challenges of complexity and information content on infinite domains. A shame, really.


Comment: Re:Why is this dribble on the front page? (Score 3, Insightful) 441

by rgbatduke (#49779669) Attached to: Creationists Manipulating Search Results

An interesting science fiction plot that has been used so many times it is hackneyed.

It is also a horrendous abuse of the concepts of quantum theory. The problem with the hypothesis of God is that there has been no reproducible, objective, measurement or observation of God. Quite the contrary. The Universe unfolds precisely as if there were no such thing as God, with truly awesome, mind-boggling consistency, follow rules known only approximately (so far) as the "Laws of Nature" which leave no room whatsoever for God, unless it is God's will that the Universe evolve in time as if there were no God.

This is a far cry from asserting that the Aharanov-Bohm effect implies God, even allowing for the imprecision of stating that particles can be "controlled" by observing them, and worshipping something has never, as far as I know, caused that something to come to be.

Finally, there is an information-theoretic argument that proves it quite impossible to create a God by any means such as you suggest. It is quite literally as impossible as reconstructing an encoded string a gazillion bytes long from a single tiny fragment of that encoded string. The information content of God has to be greater than or equal to the information content of the Universe (this is literally the God-property of omniscience). I am a (very) finite part of the Universe. I have enormous (information) entropy relative to the Universe quite aside of the possibility that I have in some sense a quantum indeterminacy in my state. God (if God exists) has zero entropy, quantum Universe or not. There is simply no way the former can generate the latter. Violating the second law of thermodynamics is an understatement.


Comment: Re:Why is this dribble on the front page? (Score 5, Informative) 441

by rgbatduke (#49779575) Attached to: Creationists Manipulating Search Results

The real problem is, in an infinite, probabilistic universe, even the smallest chance that God exists is a certainty. Of course, there is no shortage of conflicting, self defeating pseudo-science airheads that will believe anything else rather than making an attempt at living a Christian life with a little less ego.

I do not think that this "probability" means what you think it means.

I will try to tell you. No, it is too much, I will sum up.

Suppose you have an infinite barrel of marbles, 10% of which are green. Then the probability of drawing a green marble is (wait for it) 10%. This isn't a particularly small probability. If there is a single green marble, somewhere in the barrel, the probability of drawing it is asymptotically zero, statistically neglible, less than the chance of winning the lottery, and winning the lottery in one try is far from certain. If the probability that God exists is 1 x 10^{-403} in an infinite, probabilistic Universe, then the probability that God exists is (gasp) 1 x 10^{-403}. This is most definitely not certainty. Certainty isn't the "smallest chance", it is probability 1. It is the largest (possible) chance.

Even 1 x 10^{-403} isn't in the same ballpark as "the smallest chance", by the way. It is enormous compared to the probability that all of the air molecules in the room I'm in will suddenly (by pure chance) happen to bounce in just the right way to form a big blob of liquid air in the middle of the room and leave me gasping in a vacuum as air molecules outside of the house by strange chance miss all of the myriad pathways into the room. Which in turn is unbelievably, awesomely hugely enormous compared to the probability that the infinite, probabilistic Universe is in fact determined and known at the subatomic level by a perfectly organized, uncreated, omniscient, omnipotent, omnipresent superbeing that created it all by pure magic from nothing.

Oh, wait -- that's a contradiction, isn't it! If the Universe is infinite and probabilistic, then it can't be infinite and deterministic and hence known by an omniscient, omnipotent being, because there is nothing less probabilistic than something that is completely determined by an all powerful, all-knowing being. So your premises directly contradict your conclusion, in addition to demonstrating nothing more than the simple fact that you have absolutely no clue about probability distributions on continuous spaces.

Ego aside, you might want to contemplate learning something about probability and reason itself before you argue in favor of something empirically, logically, and statistically indefensible. God (as a concept) is all three.


Comment: Re:Aren't they called Currents? (Score 1) 61

by rgbatduke (#49750055) Attached to: Subsurface Ocean Waves Can Be More Than 500 Meters High

To be fussy (and as a physicist I am nothing if not fussy), one can either describe everything in fluid motion as waves simply because the medium is (somewhat) elastic and one can construct a wave equation to describe the propagation of pressure differences, or one can use the Navier-Stokes equations straight up and solve for bulk transport properties. We don't usually refer to the bulk transport as waves. When I stir my wort making beer and get it going in a nice cylindrical eddy in the cylindrical pot, decomposing this bulk transport in a wave description makes little sense, even though the motion is undoubtedly periodic, and it is difficult to see it as the outcome of a suitable transformation of the N-S equations into a real-valued second order PDE in space and effectively second order in time, which is what one usually "expects" for "waves". Second order in time leads to solutions that are either exponential (not waves) or harmonic (waves), with life getting more complicated to the extent that things are generally nonlinear in the N-S equations.

Similarly, I personally wouldn't describe the thermohaline circulation of the ocean as "a wave", or stable currents as "waves", or the flow of water downhill in a stream as "waves", or laminar flow in general as "waves" and am not sure that I'd even describe eddies and the onset of turbulence as waves, although there finally, in the vicinity of the conditions where laminar instabilities can grow and initiate turbulence, a wave description might start to be sensible as periodic propagating wave-like structures appear (even though they probably don't satisfy any sort of sensible wave equation)

Note that your example of shock waves is a good one, as they result when the overpressure in air waves exceeds one atmosphere, at which point (if not long before) the wave equation that was very nearly linear becomes very definitely nonlinear, as the wave underpressure is clipped at 0 atm (a vacuum) but the overpressure is unconstrained. The resulting nonlinear equations can support e.g. solitonic solutions, propagating hyperbolic secants plus a reverberations as the air subsides into normal waves again from nonlinearities in the dispersion. I'd still categorize these as "waves" as they represent a specific limiting behavior of the wave equation with nonlinearities.

So the real question is, are the waves discovered by the MIT volken describable by suitably approximated/linearized second order time equations with complex time solutions (granting that one will still have second order space equations describing the fluctuations away from equilibrium in the bulk medium) ? Or are they first order in time, describing bulk transport but without any elastic "wave" to the wave? Are they just currents in the ocean, or are they currents in the ocean with periods, with wavelengths, or even with solitonic properties e.g. shock fronts?

After all, we know already that the ocean supports waves with wavelengths constrained only by its physical and thermoisobaric geometry and boundaries. There is no "low frequency cutoff" per se in the wave equation that describes sound waves in the water that I know of. In much of the deep ocean, the speed of sound is around 1.5 km/sec, so a 10 Hz wave has a wavelength of 150 meters. A wave with wavelength 500 m has a frequency of 3 Hz. Of course waves with this sort of wavelength propagate in the free ocean in all 3 dimensions, so variations 500 meters "high" can and almost certainly do exist.

It is this last terminology that is very odd. In a transverse wave propagating on e.g. a one dimensional string, the wave amplitude can be described as being thus and such "high", where high is understood to be perpendicular to the direction of propagation. In surface waves in the water (a mix of longitudinal and transverse waves) the wave one can discuss the longitudinal and transverse wavelengths together or separately, but again given horizontal propagation on the gravity constrained surface, transverse is understood as "high", a wave is so and so many meters high.

Underwater waves are a different matter altogether. For one thing, there is no sharp interface like the water's top surface, constraining them. Sound waves are longitudinal, and one would not usually describe the amplitude as a "height" even if they were propagating or were standing waves constrained by the top and bottom boundary conditions in the vertical dimension or were a superposition of a horizontal travelling wave and a vertical stationary wave -- a sound wave propagating from right to left between two hard sheets might have modes that could be so described, but the vertical wavelengths are not really transverse wave amplitudes.

What one would like to do is interpret these words as "there exist transverse waves in the deep ocean with actual bulk transport of water up and down by distances of up to 250 meters (each way) around some undisplaced mean, with the displacement occurring in space and time. This is hard to imagine in a highly compressed dense fluid effectively constrained between two surfaces, because it has to satisfy a continuity equation -- one cannot move water up without more water flowing in to replace it on the bottom from somewhere, and without it flowing out of the way on top to somewhere.

Structures like this are not impossible to the N-S equation -- little is, really. One can imagine, for example, a set of convective rolls that propagate around in some closed path. In order for this to be "a wave", IMO the rolls cannot be stationary in their local medium, but actually have to propagate on top of any bulk transport of the medium in e.g. a current. Convective rolls in the Gulf Stream that are just going around in the moving frame but are moving relative to the stationary ground wouldn't count, as the bulk transport is driven by something (thermohaline density changes, atmospheric flow, coriolis forces, non-Markovian history, and boundary conditions) completely independent of the process that creates and amplifies the convective rolls.


Comment: Bad dog! No biscuit! (Score 1) 46

I'm just waiting for drones that will simultaneously cut my lawn and deter burglars.

According to Gary Larson, that would be robodog Ginger featured in "You call that mowing the lawn? Bad dog! No biscuit!" Well, you might have to put a beanie prop-hat on the dog, but it would be pretty close...

Comment: Re:Too bad (Score 2) 66

To paraphrase, you can't be too rich, too thin, or have too many bits of precision in a calculation. With single precision you have to be enormously careful not to drop digits even in comparatively modest loops; with double precision you can many digits before you run out. You can see it in almost any computations involving trig and pi -- single precision pi degrades in series much faster than double precision pi. It isn't just a matter of not using forward recursion to evaluate bessel functions, which is unstable in any precision (or for that matter, using book definitions of e.g. spherical bessel functions in terms of trig functions) or reordering series to avoid subtracting big numbers and running small to big instead of big to small -- there is simply a big difference between cumulating a random walk with a random digit at the 16th place and one at the 8th place.

A second problem is the exponent. 10^38 just isn't "big" in a modern large scale computation. It is easy to overflow or underflow a single precision computation. 10^308 is a whole lot closer to big, even expressed in decibels. One can concentrate a lot more on writing simple code, and a lot less on handling exponent problems as they emerge.

A final problem is random numbers. This is actually a rather big problem, as lots of code (all Monte Carlo, for example) relies on a stream of algorithmically random numbers that (for example) do not have a period less than the duration of the computation and that do not have significant bunching on low dimensional hyperplanes or other occult correlations. It is much more difficult to build a good random number generator on fewer bits, because the periods of the discretized iterated maps scale (badly) with reduced numbers of bits and it is more difficult to find acceptable moduli for various classes of generators from the significantly smaller discretized space. You can watch this problem emerge quite trivially by building a Mandelbrot set generator in float and rubberbanding in -- oops, you hit bottom rather quickly! Rebuild it in double and you at least have to work to rubberband in to where it all goes flat. You have to build it in a dynamically rescaleable precision to rubberband in "indefinitely" as the details you wish to resolve eventually become smaller than any given finite precision. This actually illustrates the overall problem with single precision quite nicely -- the emergent flat patches in an graphical representation of an iterated map are isomorphic to the establishment of unintended correlations in long runs of iterated maps in a random number generator and the clipping of the graphical representation of small numbers illustrates the problems with mere underflow in real computations of interest.

Personally, I dream of default quad precision and 128 bit processors. 34 decimal digits of precision means that a random walk with n unit steps (which accumulates like \sqrt{n}) require (10^30)^2 = 10^60 steps to get to where I don't still have 4 significant digits. Even a rather large cluster running a rather long time would have a hard time generating 10^60 add operations. In contrast, with only (say) 8 decimal digits a mere 10^16 operations leaves you with no digits at all, assuming you haven't overflowed already. I've run computations with a lot more than this number of operations. I also like the idea of having overflow around 10^5000. It takes quite a while adding numbers at the overflow of double precision to hit overflow, and one basically could add overflow scale single precision floats forever and never reach it. That gives me comfort. It would also make writing a Mandelbrot set explorer tool where one would be likely to give up before rubber banding all the way to the "bottom" -- there are a whole lot of halvings of scale in there to play with that still leave you with much more resolution than needed on the screen.


Comment: Mutant Great Whites... (Score 1) 193

...with laser beams! Radical!

Shades of a bad science fiction novel. Or even several bad science fiction novels.

Next up on the news at 9 -- replete from eating Fukashima, Godzilla shows up from the trenches off of Japan to eat the Independence before marching on San Francisco, plates a-glowing...

Uncompensated overtime? Just Say No.