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Comment Re:Buzzword-heavy (Score 2) 54

Double ditto. I've written magazine articles on beowulf-style supercomputers I've built at home (I used to write a column for "Cluster World" magazine in the brief time that it existed, but I also wrote an article or two for more mainstream computer mags). I have also set up clusters for companies I've founded and helped others set up corporate clusters. Some of what are arguably the world's largest parallel supercomputers -- Google's cluster, for example -- are not government funded. Many others aren't government funded, they are built by companies that sell products to many entities, among them (perhaps) the government. Aerospace engineering companies all need supercomputers to do computational fluid dynamics on hull designs, for example. Ordinary engineering companies use them to do finite element analysis. Gaming clusters are by any sensible definition a highly parallelized, dynamically partitioning supercomputer.

Ever since the invention of PVM and open source versions of MPI, anybody with a small pile of computational resources and a network has been able to implement a beowulf-style supercomputer built from them, an architecture so successful that nearly all of the supercomputers built in the world today are basically "beowulfs". I've helped a few dozen individuals (one at a time, not via my book or magazine articles) build beowulf clusters at home just to dink around with for fun, or to learn a new job skill, or to set up a learning cluster at a small community college or university. No government funding, often out of pocket funding or repurposing old computers that are lying around. Not all of these clusters could beat Moore's Law, which has inexorably eaten Amdahl's Lunch after a few years (that is, by the time they were built it was often the case that a single processor over the counter computer at the high end of clock and so on would beat the small cluster made of older systems) but there is no doubt that they were supercomputer architecture with substantial (but sublinear) speedup compared to single threaded execution times for a suitable parallelized chore.

Besides, it is useful to remember that your cell phone would have been considered a munition a bit over a decade ago. A better thing to state is that everybody buys supercomputers because almost every processor based system from navigation systems in cars to cell phones to tablets to personal computers is, these days, a supercomputer. My i7 laptop has four cores, eight contexts, and exhibits linear speedup on in-cache embarrassingly parallel code out to eight simultaneous tasks because Intel has done a pretty amazing job of internally parallelizing the execution subsystems for the contexts. It beats the hell out of almost all of the small clusters I've ever built, including clusters with many, many more nodes. Build even a small stack of i7 systems on a gigabit or better network -- two, for example -- and you've got a sixteen core supercomputer with a complex communication topology (variable speeds and nonlinear thresholds, as the i7 does stop giving you the purely linear 8 way speedup for large enough tasks and drops down to a bit over four -- again an instance of "superlinear speedup" of parallel code even WITHOUT using a fancy tool if you simply count cores instead of context and ignore internal parallelism for certain kinds of code that permits a single core to be managing memory I/O for one task while executing the other).

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Comment Re:Buzzword-heavy (Score 2) 54

Hey, don't disrespect physicists in parallel computing. Some of us actually understand how to do it properly and agree with what you state. Superlinear speedup is not precisely unknown, but it is rare and depends on architectural "tricks" that typically preserve Amdahl's law at a low level but apparently violate it at a higher level. In the naivest, stupidest example, if we didn't count cores instead of processors, even embarrassingly parallel code would exhibit superlinear speedup on a single processor system. Replace core count with internal ALUs, pipelines, SIMD/MIMD in the architecture, onboard vector units, etc, and one can get the same sort of thing per core for just the right code.

I am deeply skeptical of any sort of toolset that purports to be able to either statically or dynamically partition a given set of upper level code to get superlinear speedup. I won't say it is impossible to build a set that "works" for some fraction of the parallelizable code in the Universe, but given the complex tradeoffs between computation and communication in different communication topologies and task partitionings, this is not a problem that has a simple universal solution and I suspect that in lots of cases an experienced parallel programming human being could spend a half day analyzing the code and architecture and beat (or tie, as the USUAL rule is going to be no meaningful superlinear speedup boring for coarse grained parallel or embarrassingly parallel code) the output from an automated tool.

An interesting example of a tool that does this sort of tuning (semi-empirically!) that works is ATLAS, the automatically tuned linear algebra system. Basically it does a search of the space of partitionings and algorithms to determine the best combination of the two for performing basic linear algebra functions (BLAS) and then implements it in a transparent library. It is semi-empirical because it is nearly impossible to predict the overall effect of every combination of SSE support, clock speed, bus speed, core architecture -- it is a lot easier to just go and find out. But the problem ATLAS solves is comparatively simple relative to even static task partitioning on heterogeneous computational resources with variable costs for core-to-core communication, especially in today's multicore world where one has different speeds between cores on a processor, between processors in a system, between systems, between general purpose processors and special purpose e.g. GPU/vector processors, where the communication topology itself can have a major impact on the kind of parallel speedup any given task has.

This, then, is the interesting part as you note, and who knows, maybe they've built a sufficiently intelligent system to get nominally superlinear speedup (or hell, who cares, just getting close to optimal speedup sublinear or not) from a meaningful fraction of the space of possible parallizable code. But God couldn't get superlinear speedup on fine grained synchronous parallel code with long range coupling out of any multi-node scalable parallel architecture available in the real world today, no matter how fancy the partitioning tool.

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Comment Re:Pentaquark (Score 1) 111

Aw, now you are being rational. C'mon, when somebody sees a transluminal neutrino, traps a magnetic monopole, measures a signal that might possibly be the long lost Higgs boson, you can't go around doubting it. Where would climate science be if one doubted the spaghetti-snarl output of all of the GCMs and Hansen's predictions of 5 meter SLR by 2100? Where would medicine be if we doubted that oat bran and fish oil pills prevent heart attacks? Where would the Middle East be if all of a sudden all of the Muslims, Christians and Jews suddenly doubted the Bible, Koran, etc, especially the good parts where he promises land to this or that group or gives it permission to enslave or otherwise abuse non-believers?

Next you're going to tell me that "dark matter" might ultimately turn out to be a lot more brown dwarfs than we think there are instead of new physics that enables interstellar transportation. Spoilsport.

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Comment Re:I'm gonna become rich! (Score 1) 311

Curiously, I did this too (physicists all love big sparks and explosions, I guess:-)

I built it to melt metal in my basement. So (being twelve and stupid at the time) I struck the arc, and bang, there it was tremendously bright. I happened to be in bare feet standing on the damp basement floor, so I grabbed a handy nail in a pair of metal pliers, wrapped a paper towel around the handles, and stuck the nail into the arc (and mind you, I didn't have anything like eye protection, I'm standing there in my shorts and tee shirt, right?).

After I picked myself up off of the floor, I thought "Damn, I guess I needed more paper towels". So I rewrapped the handles in a double layer of paper towels and stuck the nail into the arc again.

After I picked myself up off the floor a second time, I shook myself off, unplugged the arc lamp, and never ran it again (probably saving my vision, my heart, my life, and perhaps the house...) But it did work to make me smarter! So did taking a hit of 100,000 volts or so through a fluorescent tube straight from a homemade Tesla coil!

I can't imagine what I was doing, risking burning my family alive, the tragedy of my death, my eyesight... Wait, insight fading, fading....

Hey, has anybody got a roll of magnet wire? What would happen if we drove a carbon arc from a really big Tesla coil in a stream of pure Deuterium gas? I bet we could get thermonuclear fusion going in my basement!

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Comment Re:Shocking... (Score 2) 160

I've shot myself (by accident) with a 410 shotgun at close range (blowing off my thumb in the process) and -- d'ya think? First person shooters where people get shot repeatedly and overrun a heath kit and are suddenly better (and didn't just die as their limbs and organs were blown off or perforated) aren't realistic?

Damn. Who knew?

I'm taking back my original copies of Duke Nukem and Doom, and trading them in for a realistic game like Mortal Combat or World of Warcraft.

Or let's rewrite all first person shooters so:

a) Getting shot triggers dog zap collars or taser clips attached to various parts of your body set to a level that is not quite lethal. Make love, not war, Baby...;-)

b) If you persist in play after you get shot the first time (non-fatally) and eventually get shot and die (Ouch! Twenty minutes on the floor twitching before your muscles will work again!) you never, ever get to play the game again. In fact, you have to sell your computer and join the peace corps to help villagers in South India build waste treatment plants and safe wells.

Still not realistic -- take it from me, getting shot hurts like hell even when it doesn't kill you but merely maims you a bit -- but far more instructive...

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Comment Re:Shocking... (Score 2) 160

Sauron had nukes and biologicals and binary nerve gases, silly beanie. The only reason hobbits survived the first war at all is because their little hobbit holes double as fallout shelters and their immune systems were strong from walking around all of the time without shoes. Also, hobbits are very fond of mushrooms and other alkaloid-containing herbs and have evolved a remarkable resistance to toxins. Their powerfully detoxifying livers are roughly a third of their body weight, after a lifetime of quaffing and smoking pipeweed.

So no, not the most powerful force. "Cannon fodder" would be the right term. In fact, they were just the right size to shoot from cannons.

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Comment Re:Ah, yes! (Score 1) 315

Just for the record, I'm a PhD physicist, graduated from and teach at a major research university, and think both ID and creationism are utterly absurd propositions, repeatedly confounded by observation after observation. Believing in things without evidence, or in the teeth of directly contradictory evidence, is certainly possible for anybody, including physicists who should know better, but it almost invariably involves being brainwashed when they were too young to know better or think critically into thinking that antique scriptural writings had some magical cachet that simply looking at the world and letting it speak for itself does not.

Evidence directly contradicting creationism in physics starts with this little thing called the Law of Conservation of Mass-Energy . This law states in essence that we have never observed the mass-energy content of the Universe being increased or decreased (outside of the tiny transient violation in quantum theory). Ever. Not as far away as we can see with the biggest telescopes. Not as far back in time as we can see with the biggest telescopes. Not in the laboratory. Not in any physical theory that works to explain a whole host of experimental observations not directly concerned with energy. Not in our everyday lives, where I can be confident that the bed in my bedroom is still there when I cannot see it because mass-energy is conserved.

Empirically, there isn't any good reason to believe that anything, ever was created ex nihilo, let alone everything. It's as silly as believing that the dark side of the moon contains a full-featured Disney resort underneath a crater somewhere, just because we haven't looked (yet), or if you think that is too easy to falsify, believing that there exists a full-featured Disney resort on a moon orbiting the fourth planet orbiting Arcturus, or a full-featured Disney resort "in Heaven" (making it really impossible to obtain either positive or negative evidence.

Then (since you bring it up) there is the information theoretic argument. Both creationism and ID sweep under the rug the entire issue of information theory and intelligence and entropy. Here's precisely how idiotic it is:

We observe complex structure in the real Universe. One asserts -- without proof, and rather in contradiction to both everyday observation of a multiplicity of entirely natural complex forms and common sense -- that complex forms cannot occur naturally. To explain them, we invoke intelligence that must have designed/created the complex forms, the basic teleological "watch implies a watchmaker" argument for God. But of course this makes God even more complex, and by the same argument, even more unlikely to have occurred naturally! The hypothesis thus begins with a special exception -- a natural entity, God, is permitted to have infinitely more complexity than any complexity we observe in nature, all because somebody has a hard time believing that complexity in nature can come about without an active intelligence designing it. Who designs the designer?

Entropy is even worse. All of our observations of "intelligence" involve considerable structure and a fairly rigorous state-switching mechanism supported by physical biology and/or electronics. Entropy is (literally) the log of the missing information (to a physicist) and there are theorems concerning energy, entropy, and heat generation in switching mechanisms supporting intelligence. To be able to perceive time at all -- to enable free will, the ability to act on the basis of an uncertain future -- one requires a point of view that has incomplete information. The derivation of the Nakajima-Zwanzig equation for the time evolution of an open (quantum) system embedded in a larger Universe typifies how intelligent agents have entropy bleed into them from an uncertain external universe, and hence can exhibit non-deterministic behavior. God by definition is omniscient, and omniscience sadly directly contradicts both intelligence and free will. God can only choose between alternatives when the alternatives are not certain.

To a physicist, invoking God and an intelligent creater/designer involves hypothesizing an entire META-Universe filled with structure to support the complexity and intelligence of God, one that is self-contradictory in many ways, and in every respect is far more difficult to believe than a simple explanation, supported by an enormous body of empirical evidence, that complexity spontaneously and naturally evolves out of the simple time evolution of the non-sentient observed laws of nature. This is quite wonderful enough, BTW. One doesn't really need to invent an entire mythology outside of this that can never be measured or observed and that can have any properties you like as a consequence.

We could go on -- the enormous amount of physical, historical, and direct observational evidence of evolution occurring. The genetic evidence. The astrophysical evidence. Creationism and ID are absurd given the existing evidence, although an intelligent omnipotent deity could always choose to communicate directly and alter that situation, should they wish to. So far, they haven't.

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Comment Re:You're projecting , too. (Score 1) 629

Hey, it works with me and lobster. There they are, relatively stupid crustaceans, ripping up and eating fish and the like and surely not deeply into philosophy. Then bang -- a few days later, at least some of their molecules have become -- me! Along with a few molecules of succulent melted butter that have joined other lipids that are a part of me around my belly that I could stand becoming not-me.

I'll bet I'd be delicious, slow roasted with garlic until all that fat comes dripping down over the roast, or with my belly meat cured and turned into "long bacon". More a savory dish than a sweet one.

      rgb

Comment Re:Reasons we'll never meet aliens... (Score 1) 629

Granted, but now invert it back to the question. We will never meet aliens. We might at best meet their "seed ships". Those seed ships would no doubt be equipped with AI, AI at a level that would made them "the alien intelligence" we are likely to meet. Either they are programmed to avoid already settled planets entirely (wise for so very many reasons unless you are CERTAIN that you have the biggest guns in the galaxy) or else they (think they) have the biggest guns in the galaxy and consider evolution of the fittest to be the fundamental axiom of morality, in which case the robots will proceed to sterilize the planet, or at the very least wipe out all species that could be a threat and greatly simplify the existing planetary ecosystem, and then bioform it to meet their needs and crank out lots of little B.E.M. bottle babies to take it over.

Either way, we'll STILL never meet the real aliens. One way we MIGHT -- briefly -- have a clue that they were out there. If I were a galaxy-travelling AI with the second directive, I'd just stop my ship out in the Oort cloud, pick a half dozen 10 km asteroids, build fusion-driven ion jets onto them, add moderate directional control and drop them so that they would all arrive at once, with little warning, at six selected spots on the surface of the Earth. Then wait 100 years or so for the worst of the extinction event weather swings to damp down and bring in the clowns. The only hint we'd have that there are aliens in the Universe would be the enormous improbability of a six asteroid extinction event, at most one year before it happened (one year if they don't stealth the asteroids by e.g. painting them flat black or fitting them with a mirrored cone facing the sun to reflect all incident sunlight sideways). I rather think that truly paranoid aliens would arrange it so we would have no more than a day of warning or no warning at all. Most humans would see the flash of the rock that killed them, and within minutes the shockwaves and pyroclastic flow would arrive, transforming them into dust in seconds. Scattered survivors in e.g. submarines that survived the underwater shock waves and tsunamis of the oceanic hits would come back to a surface with no human built structure standing, no food, no plants, no animals, and an Earth with near-unit albedo and millions of teratons of surplus ocean water and fine-grained ash and dust in the atmosphere. First there would be dirty rain, then cleaner snow, and the Earth would ice up, quite possibly all the way to the equator.

One would hope that the aliens would have done this before, and would have the patience to wait out the mini-ice age or the technology to bring ice ages to an end, but I don't think that even with our technological knowledge a single human would survive an attack such as this for a full decade after the event (and bear in mind that "six" and "10 km" are variables that can be adjusted to reduce that probability further still). If we had a year's warning, we could probably build or retrofit underground bunkers capable of preserving humans for that decade, but our future prospects would still be bleak. We'd still have a hostile alien roboship with effectively unlimited free energy (it can refill it's deuterium supply from the moons of Jupiter, for example) sitting on top of a gravity well in a solar system that is chock fully of rocks. There is no depth we could build a shelter that could survive a second wave of smaller rocks dropped directly on any shelters revealed by e.g. a heat signature or electromagnetic radiation or simple observation from orbit. And remember, they've got a whole century to ensure that they got every last one of the vermin inhabiting what will eventually become a steaming warm jungle or a nice dry desert or whatever their idea of an "ideal" environment is.

All of this (to them) would be entirely justified. If we were fitter than they are to spread all over the galaxy and beyond, we'd wipe them out instead of them wiping us out, right?

The tragedy is that this is precisely correct. And all it takes is ONE hyperaggressive species, where evolution of intelligence very likely is almost always going to be the gift of time to one of the most aggressive (while still socially cooperative) species almost by definition in an entire galaxy, and the "nice guy" species simply lose and die when they come in contact or discover that they are still hyperaggressive when needs must after all. The best one could hope for is that there is a galactic civilization of sorts with a collective social agreement that permits them to mutually avoid this sort of single species takeover, and that they as a civilization protect new species instead of wiping them out for their resources, perhaps along the lines of Brin's Uplift series.

Truthfully, we cannot know whether or not any of this is likely. It is enough to know that it is possible. The best plan for humans is to stay mousy quiet on a galactic scale and work hard on developing technology, world peace, world civilization, and an outward-looking plan to expand into our own solar system, both for resources and for knowledge. Sanity demands that we assume any aliens we might discover to be hyperaggressive, dangerous, and with better technology than we have (we can always turn out to be lucky and wrong a dozen times, but we only get to be right once). In the meantime, we meditate upon defenses against galactic level alien threats, and try hard to pre-defeat an invisible enemy that might not even exist but that would very likely be our worst nightmare if it did.

EVENTUALLY, perhaps, we might send out seed ships of our own. And if we had any sense at all, we'd make the sneak past any world they were sent to that turned out to be inhabited and leave no hint on the ships themselves as to where they came from, lest we stir up a hornet's nest.

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Comment Re:You're projecting , too. (Score 1) 629

Or, it's at least equally possible that far more advanced creatures have a an advanced morality/compassion/value set that recognizes that the only hope lesser beings have of becoming greater ones in the one, short, pain-filled lifetime they have is being eaten by those greater beings.

In which case, when they land, their first words might well be, "Wow! Who brought the mustard..."

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Comment Reasons we'll never meet aliens... (Score 1) 629

a) Because there aren't any aliens to meet
b) Because even if there were, they might not be within (fill in the blank with) N>3 light years from us.
c) Because absolutely trivial physics suggests that for ANY constructed object to travel N > 3 LY, or 18 trillion miles, it would require stupendous amounts of energy. At one kilometer per second -- 1 megajoule per two kilograms of payload -- it would still take 300,000 YEARS to travel ONE light year. To cut travel time down to 300 years, one would have to travel at 1000 kilometers per second, at an energy cost of 1terajoule per two kilograms, and shortly after that one has to start paying a relativistic penalty and get less and less benefit for each doubling in energy cost. Any propulsion system that involved reaction mass would have to lift MANY orders of magnitude more mass, multiplying this already absurd number by a much larger absurd number.

True, there is always the chance of new physics, of "warp drives" and other such stuff, but that so far is pure science fiction, and if anything the fact that we AREN'T up to our armpits in smelly alien suggests that either there REALLY aren't any aliens to meet or that there is no such new physics out there to discover.

I love SF, and am a physicist and thrilled at the prospect of new physics, but when answering an open ended question it is always better to base the answer on what is known, not what MIGHT be true, if life were a Heinlein novel. Based on known physics, we'll never meet aliens because it is effectively impossible to travel in person between the stars.

Sending one's genetic code, OTOH, might be doable, if you could get it past the customs and immigration people who might not be thrilled at us cloning a potentially hostile competitive species and raising it out of all natural cultural context just to say high to a life form that didn't evolve on Earth.

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Comment Re:Thank you, Higgs! (Score 2) 259

It is fair to note that we have never observed an act of creation, in the literal sense. Indeed, the correct statement of the relevant, empirically supported physics is:

Mass-energy is neither created nor destroyed, but simply changes form.

More sophisticated field-theoretic statements conserve "information" as fundamentally as mass-energy, but the point is that these are conservation laws, things we have never observed to fail in an enormous range of observations and experiments and spacetime scales ranging from cosmology to the smallest scales we can currently measure.

The really, really interesting question is why anyone would have a "creation" theory for anything, given that we have yet to make a single concrete observation of a creation event of any sort, anywhere, at any time, or even find a way of inferring that such an event once upon a time might of occurred. All we have ever observed is things that already existed changing form. The Universe we can observe is a dance of existing stuff back as far as we can see in time, away as far as we can see in space, at all scales from the largest to the smallest that we can measure.

There is an interesting information theoretic argument that essentially proves that for an omniscient God to not be inconsistent, it has to be the Universe. In order to be omniscient and self-knowledgeable, the irreducible information content of God has to precisely match the irreducible information content of the Universe, defining the Universe as everything that exists (which must include God, if God exists). All of our observations of "sentience" or a sense of passing time involve entropy, and our understanding of reasoning and sentience as a dynamical state that changes over time further suggests that it is almost certainly meaningless to assign a property such as "sentience" to a Universe per se, no matter how complex, and the assertion of entropy as a measure of state change over time contradicts zero-entropy perfect knowledge. So there isn't any really great reason to conclude that the Universe is any sort of sentient God, but that's pretty much the only model (besides God as the really big and powerful but entirely mortal and time-bound space alien with technology that looks like magic) that isn't egregiously inconsistent.

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Comment Re:Thank you, Higgs! (Score 2) 259

Surely you jest. The Bible is disproven repeatedly. It is massively internally self-contradictory (and hence literally cannot possibly be true in its entirety). The book of Genesis is disproven -- not just not proven to be true, but proven to be false, proven to contradict a great deal of empirically founded, macroscopically and microscopically consistent knowledge, things that we accept as almost certainly true, beyond any sane question, every day.

It is difficult to even know where to begin in listing the problems in Genesis, as it isn't even approximately or metaphorically correct in its description of creation -- it has things in the wrong order, an absurd order temporally, it has nothing whatsoever that describes the actual processes any rational person would infer looking at the actual data. It gets the age enormously wrong. It gets the size wrong. It gets the structure wrong. It posits the story of a truly absurd flood (6 inches of rain a minute for 40 days straight to barely cover Mount Everest) and a Wal-Mart sized wooden boat ventilated through a carefully described one-square-cubit window in which every species on Earth that would be killed by such a flood -- which would be damn near every species on Earth -- was preserved. It describes a creation process for humans that never happened and is directly contradicted by the fossil record, introduced as an equally absurd explanation of theodicy -- the contradiction between believing in a compassionate and loving God and the existence of evil. It asserts that the Earth is the center of all things, floats on the ocean, and is surmounted by a solid bowl of sky hung with lights and pierced with holes through which God pours rain. It asserts that the stars can be shaken down by things like Earthquakes.

The "history" of the Bible is equally absurd and is contradicted repeatedly by archeology. Again it is difficult to know where to begin, but Tubal Cain as an "artificer of iron" is an excellent example, given that any Biblical timeline would put Tubal Cain several thousand years before the iron age. Iron, in other words, literally hadn't been invented yet. There isn't a shred of evidence outside of the assertions of the Bible itself that Moses ever existed (any more than there is evidence for Adam and Eve, or Noah, or any of the other figures from Genesis or Exodus). Jesus clearly was not omniscient or clued in on this, as he asserted on more than one occasion that Noah and the flood was a real person and real event (generally when predicting a similar apocalyptic event that never happened).

Besides, even if the Bible (old testament) were a nearly perfect history, instead of an obvious collection of fables, myths, legends, a mish-mosh of earlier Sumerian legends that dates no earlier than the first thousand years or so BCE that would not constitute any sort of evidence for the truth of its creation myths, any more than the creation myths of the Hindu religion are "proven" when somebody discovers that e.g. Mathura from the Mahabharata actually existed at some point in the past. I can write entire fantasies about (say) the Civil War with all sorts of characters that never existed and events that never happened and yet salt the story with references to things that did happen and people that did exist. I can even insert space aliens, or (in the case of the Iliad) with Gods. Does the Greek pantheon of Gods actually exist because they are characters in the Iliad and we've now discovered the site of ancient Troy? Does this prove Greco-Roman paganism, creation myth and all?

Look. I mean that quite literally. Forget the big bang and just look. You can, if you look for it, find and follow the entire historical argument and evidence for estimates of the size and age of the Universe. It isn't hidden, and isn't mysterious. Nor is it the product of "scientists with an agenda" unless that agenda is doing their best to figure out what really happened by letting the world speak for itself rather than taking an antique mythology written by enormously ignorant and barbaric peoples and edited and revised repeatedly over centuries seriously as a source of "truth". You have to be a child in order to do that, or to have been brainwashed as a child so that you are no longer capable of any sort of objective or analytical comparison of hypotheses given observational data.

This state is curable by education. Give it a try. Radiometric dating proves the world to almost certainly be between 4 and 5 billion years old, with multiple radioactive clocks with overlapping ranges giving consistent results. Parallax, blackbody theory, and the Hertzsprung-Russell diagram one builds by studying those stars close enough to be ranged using parallax permit one to build a stellar-distance ruler. Studies of certain kinds of very bright stars and events permit one to build a galactic distance ruler. Studies of redshifted galaxies plotted against their distance permit one to built a "universal" distance ruler, one that pushes the size of the visible Universe easily out into the billions of light years away, billions of light years old. You can doubt that the Universe is exactly 13.7 billion years old post Big Bang (or whatever you want to call the event that is visible in the night sky in the form of 3K blackboard radiation) but it is difficult to challenge the assertion that it is at least (say) 13+ billion years old, a far cry from 6 to 10 thousand.

The radiometrically dated fossil record tells a compelling story of the evolution of species over some 4 billion years -- almost from the point where the Earth coalesced and cooled out of the stardust leftover the previous supernova that eventually became our sun and its planets and had a surface containing free water. Wherever we look -- at the age of meteors, at the age of rocks we've collected from the moon -- we get similar numbers. Billions, not thousands. A parade of species evolving over time, not a single creation event in which all species were rapidly "hand made" and stuck down on the Earth by a mythical hand. When we study the DNA of all of the species that currently survive (and a number that have gone extinct) it tells exactly the same story. Evolutionary biology makes sense. If it didn't, don't you think that one or two of the hundreds of thousands of students that have taken it might have noticed? We don't burn them alive for heresy, the way that the Church did for well over a thousand years when its tenets were challenged. We reward heretics in science with Nobel Prizes, once their heresy is proven to be a better description of things than the set of trial knowledge it replaces.

To conclude, the Bible is imperfect, flawed, full of easily verifiable falsehood and ethical monstrosity, and in the end it was written, and repeatedly rewritten by men. If you want something that isn't tainted by mankind, a 2 to 3 thousand year old scriptural mythology isn't the place to look.

Try looking up at the stars. Try looking down at the rocks beneath your feet. They have a story to tell, an explanation to give, that is utterly untainted and indeed, untaintable by men. You don't have to believe me because I have some special authority. You are completely free to repeat, for yourself, the entire series of observations and experiments that support scientific beliefs as most-probable truth (so far). Students in my physics class, like students in modern chemistry and biology classes around the world, are required to do quite a few of those very experiments as they learn. Not to "learn the scientific method" per se -- in large part so that they can see for themselves that nobody is bullshitting them, gravity really does work thus and such of a way, that this and that chemical, combined, do indeed react to make the following byproducts, that paleontology provides at broadly consistent picture of the evolution of species, that blindness cannot be cured by rubbing filthy mud made from spit in a blind person's eye as Jesus reportedly did (and indeed, is more likely to help blind a normally sighted person from the possible infection).

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