Feeds:
Posts
Comments

Posts Tagged ‘physics’

This is my 500th post on this blog.

It shouldn’t have taken more than 900 days to get this far, ideally, but we’re here now, and I think I’ve been getting the hang of it lately.

So, to celebrate, let’s have some comedy.

If you’re not familiar with Conservapedia, it is fucking hilarious. But today’s specific entertainment is the page on counterexamples to relativity. (Thanks to Brian Cox for bringing this to the attention of Twitter recently.)

The theory of relativity is a mathematical system that allows no exceptions. It is heavily promoted by liberals who like its encouragement of relativism and its tendency to mislead people in how they view the world. Here is a list of 30 counterexamples: any one of them shows that the theory is incorrect.

Yep, it turns out you don’t have to have a scientific background or spend years studying physics to be able to disprove Einstein. You just have to be sufficiently right-wing. That’s all it takes to be a genius!

Look, scientists don’t claim that relativity is perfect and complete and explains everything in the Universe flawlessly. Reconciling general relativity with quantum theory is one of the big unsettled problems of physics today. But in the arena to which they apply, the general and special theories of relativity are the best we’ve got. When there are discrepancies between nature and relativity, they tend to be smaller than the discrepancies between nature and any other theory. That’s why we bother with them at all.

It’s unclear what the Conservatards think would act as a superior alternative to relativity. Neither classical mechanics nor quantum mechanics is violently decried as an elitist liberal conspiracy, so clearly they’re not disapproved of very strongly. (Though, if you’ve passed high school physics, their thoughts on the Heisenberg Uncertainty Principle should give you a giggle.)

Some of my favourite bits:

– #5 is a question. It’s not even making a statement. Is it meant to be rhetorical?

– #7 seems to assume the Big Bang model of the universe, which is very much not Conservapedia’s usual style.

– #9 is a Bible quote. To disprove relativity. Which has literally nothing to do with anything.

– #11 completely ignores the theory’s consistency with any evidence, and just says that it’s wrong because it hasn’t led to any further “insights”. This is like insisting that, if you beat your friend in a game of basketball, you must be taller than him, and ignoring whatever happens when someone gets out a tape measure.

– #18 is even funnier: relativity led to the atomic bomb, which is bad because it kills people, therefore the theory is false. Seriously. Icing sugar has carbs and will make you fat; therefore the cake is a lie.

– #28 brings up the first chapter of Genesis, which is more like it (though destroys the usefulness of #7 as a counterexample). It also randomly decides that the firmament described in the Bible “likely refers to the creation of the luminiferous aether”. What the fuck an outdated theory essentially disproven by the end of the 19th century has to do with anything, or how it disproves relativity, I have no idea.

– Whoever compiled this list basically has no idea what any physics means. Even I can explain why #16, #20, #25, #27, #29, and #30 are just factually incorrect. And the Twin Paradox one wasn’t hard to look up. That stuff’s been experimentally verified too, for what it’s worth.

Oh dear, I was supposed to just present this without comment for your amusement, but I seem to have ended up rather rambling on. Terribly sorry.

Advertisements

Read Full Post »

Here’s a fun drinking game.

Watch this video of some homeopathic woo-merchant talking about mass-energy equivalence…

…and knock back a shot every time you involuntarily frown in bemusement and think: “What the hell are you talking about?”

It’s like she’s taken a book on general relativity for six-year-olds, mostly just looked at the pictures, then spent an hour banging her head against a wall so that the few sensible scientific ideas she learnt got all jumbled up in her brain with everything crazy that was already in there.

When she’s not getting something completely wrong, it’s generally because what she’s saying literally doesn’t mean anything.

Oh good god, I just got to “Stephen Hawkings gave us the string theory”. And it’s getting worse.

I… Okay, is this a stealth stand-up comedy show? This is genuinely worth watching all the way through. Maybe put down any sharp things first, but… wow.

Hat-tip to PZ.

Jesus, now she’s moved on to throwing a home-made explosive device at her neighbour’s house. And it’s an analogy for how homeopathy works. I am not making this up. I love this crazy bitch.

(Hey, I went a whole blog post without bringing up the latest #singhbca gossip. Aw, dammit.)

Edit 28/10/09: As in so many areas of awesomeness, Steve Novella surpasses me by far.

Read Full Post »

So, I guess I should’ve done this one sooner. Pseudoscience is pretty much the pinnacle of anathema to everything I’m struggling for on this blog (hey, writing dozens of words about stuff as often as five or six times a month is a real struggle sometimes). I’m all about science, and a worldview based on empirical data and testable theories. I’m an atheist, but the interesting fight isn’t just against religion, it’s against the irrationality and flawed thinking that underlies all kinds of non-reality-based beliefs and ideas, religion included.

Pseudoscience is what you get when a hopeful but misleading patina of science is used to try and smarten up some ideas which, however nice they might be, have no connection to the real world. It’s some phenomenon or notion whose fans will stand by it unwaveringly, regardless of whether it’s actually supported by any evidence. Astrology, for instance, is widely regarded as a pseudoscience. Its claims can be shown to be empty and meaningless once you bring a few actual scientific investigative techniques into it, and its adherents have to sacrifice intellectual honesty to scrape together a flimsy charade of supporting evidence.

Obviously nobody ever thinks that what they’re doing is pseudoscience. People don’t believe that they’re deliberately ignoring contradictory evidence and sticking to unsupported claims long after they’ve been shown conclusively to be untenable. They’re much more likely to think that they’re steadfastly fighting an uphill battle for a truth that the rest of the world is too blind to accept. As a result, it’s sometimes hard to untangle good, healthy debate and disagreement on the one hand, from actual pseudoscientific nonsense on the other. When people have conflicting ideas, how can you tell if there’s a reasonable, scientific difference in opposing parties’ interpretations of the data, or if one side’s just full of shit?

Well, despite what contradictory views different people might have on Ufology, or Bigfootonomy, or the current deadness-to-aliveness quotient of Elvis Presley, there are some definite protocols and standards which you have to adhere to if you want to legitimately call what you’re doing science.

When addressing pseudoscience, it’s not really constructive or desirable to simply declare “This entire field of study is bunk”, regardless of how tempting it might often be. There’s always the possibility that someone may come along and provide a robust scientific theory about something we might have written off as complete crap – and if there’s ever any evidence that this is what’s happened, we need to be open to it. But a lot of stuff is bullshit, has no supportive evidence, and isn’t likely to anytime soon.

So, rather than simply listing a number of disciplines which are stamped irreparably with the label “Pseudoscience” and may never be taken seriously by anyone who values their scientific credibility, more common is to provide a list of “red flags” – things which generally indicate poor methodology, irrational and ideology-driven research, and that you would do well to be more than usually doubtful about.

What follows is a list of these things to look out for, which should warn you that proper science might not be at the top of the agenda. I’m taking a lot of cues from similar lists at Skeptoid, and these three wikis, but with my own suggestions for how best to calibrate your bullshit detector.

Decrying the scientific method as inappropriate or inadequate to apply to this particular claim

Look, science is just awesome. As the internets are so often keen to point out (and score geek cred for referencing xkcd), it works, bitches. If you’re doing science, you really ought to have a pretty good understanding of how it works (which isn’t hard to grasp), and why it’s important to apply these principles to any new hypothesis before we credit it with being probably true.

This means that, if you’re going to claim that your new idea will revolutionise our understanding of the universe, you can’t get all touchy and offended when people start asking for proof, trying to knock it down, poking holes in it, and bringing up whatever pesky facts might cast doubt upon it. They just want to know you’re not as full of shit as all those loons with their own Grand Unifying Theories, who share your passion but whose ideas don’t make a lick of sense.

If you want people to take you seriously, and believe that you’re any different from the loons, you should be doing everything in your power to help them with their knocking and poking. Because however much this hypothesis is your beautiful darling baby, and you know it will change the world and make you a hero and persuade everyone to shove that haggard old Liberty bint out of the way to make room for a statue of you, you must never forget the crucial and constant scientific principle that it might all be total bollocks.

If you’re wrong, you should really be keen to find that out. If you’re right, you’ll have a theory that’s all the stronger and more convincing for having withstood everything that humanity’s current scientific understanding could hurl against it. This has been the path of every established theory in the whole of science. You are not above this process.

This includes medical practitioners who claim that they don’t have time to waste performing rigorous scientific tests on the alternative treatments they’re dishing out, because they’re “too busy curing people” to bother with any of that. As if all those researchers painstakingly performing controlled studies to determine the actual effects of their treatments are just trying to find ways to pass the time.

One person’s subjective interpretation of one small set of data points – say, how an individual doctor remembers the general feedback he’s got from a handful of patients about a particular pill he’s been giving them – is a far less effective way of finding out the real effects of a treatment than a proper, blinded, scientific study, which can include information from thousands of people and rule out countless potential sources of bias. These studies are why you’re not likely to get a prescription of leeches or thalidomide from your GP anytime soon. They’re the best way we have of finding out what reality is like. (Read Ben Goldacre‘s book for a more thorough discussion of things like the placebo effect, observer bias, and the numerous other phenomena which can make our personal judgments totally unreliable when it comes to the efficacy of medical treatments.)

Being batshit crazy

Now, granted, some batshit crazy stuff does in fact turn out to be real, like quantum mechanics or Mr. T, but these examples are relatively few. You can label yourself a mould-breaking freethinker unfettered by the constrictions of current paradigms, but that won’t stop people calling you an ignorant jackass. Yes, Galileo was right, even though he was viewed as heretical by an oppressive establishment dogmatically set in its ways. But just the second thing on its own isn’t enough.

It might not sit well with the part of us that wants to cheer on the underdog, and see some high-and-mighty ivory-tower types collapse under their own hubris, but most claims which totally contradict established science are going to turn out to be completely wrong. In most cases, such science is established for good reason, and has a lot of data backing it up. If all of this is going to be overturned, it probably won’t be because of a single set of results from one new experiment – particularly given how easy it is for the ignorant, scientifically illiterate, and borderline mentally unstable to make scientific claims.

Obviously this new claim may end up being borne out over time, and the old ideas will then need to be abandoned – but for every Galileo, there’s a thousand whining ideologues, raving lunatics, or honestly mistaken researchers who thought they might’ve discovered something they could publish a career-making paper on but are finding it too painful to admit to themselves that they’ve been barking up the wrong tree.

Science by press conference

Good news, everyone! I’ve invented a new type of fish which completely vanishes when left unattended, leaving no decaying and unhygenic remains behind at all! It totally worked this one time, when Reid and Hofstadter from the physics lab challenged me to an office-chair race, and I left it completely unattended. Except for my cat, who’d been asleep by the test tube rack, but he definitely wasn’t involved. He’s not a scientist. He hasn’t even got a PhD. The point is, I’m a groundbreaking genius, and now I need substantial funding for further research. Yes, mine is the only lab to have produced any such results so far. Yes, it’s just the one result. But we’re all very excited by the empty, slightly greasy plate which constitutes our lone data point, and we look forward to developing this technology into something accessible to everyone. Did you hear what I said about funding?”

There’s a reason very little actual science tends to turn up this way, in sudden monumental bursts, where whole long-standing paradigms are suddenly overturned in one brief newscast. If someone gathers together a horde of journalists, camera crews, and other sundry spectators, to make some grand announcement about a world-shattering scientific accomplishment never before mentioned in the public sphere, then there’s a good chance that they may have taken one or two short-cuts in the actual science.

Science depends on peer review and replication of results – if you give the details of your experiments to other, independent researchers, they should be able to do the same stuff as you did, if they recreate the same conditions. You have to give other scientists a chance to try it for themselves, and maybe tighten up the protocols (like not letting the cat inside the lab) to see if there might be an explanation for your results which doesn’t imply that everything you know is wrong. A good scientist doing credible work will understand and appreciate the need for this kind of scientific rigour, and welcome the opportunity either to further bolster their claims with independent evidence, or to falsify their own findings before they do something silly like call a press conference over something that will turn out to be easily disproven by the emergence of a well fed cat.

Heads I’m right, tails you’re wrong

My first point was that the best way to prove the scientific merit of your idea is to go through all the usual rigmarole of the scientific method. One specific example of this is that you need to make sure that your idea is potentially falsifiable.

There should be a constant attitude in science – especially with regard to new and unproven ideas – which goes along the lines of, “Take THAT, supposed laws of nature!” You should be trying to bitchslap every contending theory down with the most awkward facts you can muster, and be prepared to chuck it out, if it can’t take the heat and collapses into either inconsistency or tears.

You need to be doing the kinds of experiments where you can say in advance, “We’re going to do this, this, and this, and we predict that will happen. If that does indeed happen, then great, we might be onto something – but if the other turns out to happen instead, then we’re going to have to rethink this theory.” You need to be able to point out, ahead of time, what observations could be made, which would blow your theory out of the water if they were ever reliably demonstrated. You try your damnedest to disprove it, and let everyone else have a go, and if they can’t, then you’ve got yourself a respectable theory.

All good science has something which could totally screw it up like this. Evolution? Precambrian rabbit. The Standard Model of particle physics? If the Higgs boson doesn’t turn up where it should be in the LHC. Science.

But how do you prove homeopathy doesn’t work? Well, you might have thought that repeated analysis of experimental data showing it to have no significant clinical effect beyond that of a placebo would count as disconfirming evidence, but its proponents don’t seem willing to take this as a sign that they need to seriously rethink their ideas. In actual medicine, new treatments are constantly being tested against those already in use, and if they don’t show a significant effect, nobody keeps pushing for them to be widely adopted. They scrap it, or make some significant changes before testing it again, and don’t keep prescribing it to people in the meantime as if it worked. Homeopaths don’t seem to work like this. If someone isn’t willing to suggest what results would falsify their hypothesis if observed, and genuinely rethink their ideas if what they predicted would happen didn’t happen, this should cast doubt on how scientific they’re being.

The pseudoscience, it ain’t a-changin’

It’s never a good sign when your supposedly scientific field goes for a long time without making any significant developments, or adapting to new information and more recent research. Any useful scientific theory makes predictions about future observations, and will generally gather supporting evidence over time as these predictions are vindicated – or, it will change and refine its ideas when new data contradicts the predictions it made.

Astrology is an excellent example in this case. There’s been almost no noticeable change to it in centuries, despite repeated disconfirming evidence, and the fact that the traditional astrological arrangement of zodiac signs simply doesn’t apply any more. I remember one day at school over a decade ago, we were discussing in class a newspaper article about the actual positions in the sky of the constellations of Leo, Aquarius, and so forth, in the modern world, compared with when the standard arrangement of western astrology was first put together. Technically, based on where the constellations actually are in the sky, it was said that my birthday should fall somewhere in Sagittarius, rather than Capricorn. But there’s been no actual progress in the study of astrology resulting from this or any other development in our understanding. It’s completely static, and oblivious to new data. This does not bode well for scientific integrity.

“Energy”

Whenever some new supposedly scientific practice or product throws the word “energy” around, take a shot. Wait, I mean, be skeptical. In science, “energy” is a term referring to a well defined concept, describing how much work (itself a well defined thermodynamical concept) can be performed by a force. In pseudoscience, it’s usually just some vague, wishy-washy notion of “life force“, which some subset of animate objects is assumed to possess, but which can apparently never be quantified, directly measured, or observed in any other way that might actually be useful. It can supposedly be “felt”, by those attuned to it, but this kind of claim doesn’t stand up even to a nine-year-old’s investigations.

If a new claim is based on harnessing “energy”, but never really explains what that means or how it’s consistent with our understanding of the physical laws of the universe, that’s a big red flag. It should never be enough that you’re expected to “feel” something working, because there are many, many ways that your “feelings” can be misleading.

“Natural”

Another magic word which, when it comes to a large number of alternative medical products, health supplements and the like, shouldn’t be nearly as persuasive as it often is. “From the ecosystem that brought you such previous best-sellers as arsenic, smallpox, cocaine, and HIV, comes our new all-natural sensation…”

Obviously that last one’s not such a great example, since we all know the AIDS virus is actually a divine punishment for gayness and/or was created by the government as a means of population control. But the point still stands that Nature’s a bitch, and you should not expect her to be on your side. Chemicals designed specifically to be as beneficial to humans as possible, on the other hand, might be a better option.

Don’t go too far the other way and assume that natural = bad, or your diet will take a serious downturn – but if the “natural” quality of some remedy is being touted as a plus, there’s a good chance it’s meant to be emotionally persuasive, because there’s really nothing rational or logical to be persuaded by.

It cures cancer, makes the bed, and house-trains your unicorn

If something’s too good to be true, then it’s tautologically bullshit. And if a new scientific development comes overflowing with promises of the many wonderful ways it will change your life for the better, the problems it will solve, and the quick fixes it will fix quickly, then that should be a hint that the people making these claims might be more interested in parting some fools from their money than genuinely breaking new scientific ground. (This is especially true if the grandiose promises are being made in a high-profile public announcement, and the practical results are all still yet to materialise.)

Does it work? TRY BUY IT AND SEE FOR YOURSELF

If the people doing the research are also the people taking your money for the product whose efficacy they’ve been researching, that’s not a great sign. What should be even more suspicious is when they can’t provide any actual data to suggest that the product works, and their best suggestion is that you spend your own money (or even just your own time and effort) on performing a non-blinded and unreliable study by yourself, with a sample size of one. (That one being you. And nobody is a statistically significant sample size all on their own.)

If they’re promoting or selling it, and making claims for its effectiveness, there should really be data by now supporting the idea that it actually does something. “Don’t knock it till you’ve tried it” might be a fine way to approach, say, oysters, or bungee jumping, or homosexuality, but it’s not a sound principle on which to base scientific research.

It’s a conspiracy!

The usual reason for ideas not being accepted by the scientific community is that they’re bad science. People who claim that their amazing findings are being suppressed by a conspiracy are much more likely to fall into the “batshit crazy” category mentioned above, than to have actually achieved anything that anyone could possibly have reason to suppress. It’s much more likely that they just don’t have the data to suggest that their hypotheses are anything other than wishful thinking, and so the scientific community is justifiably uninterested.

It profoundly misunderstands the nature of science and the motives of scientists to suggest that there exists any kind of grand conspiracy which is innately hostile to new ideas, and strives to preserve the status quo. Science is all about discovery, and improving our understanding, and scientists love discovering new stuff they can’t explain, and for which they’ll have to come up with a new theory. If you’re even dimly aware of something called “the past”, and have an idea of what things were like there, and how different were the levels of technology and our understanding of the world, then it should be clear that science is anything but stagnant and unchanging.

Sometimes, an individual scientist will be too attached to their preferred, established theory to accept new data which should prompt them to update their ideas. But the process as a whole is geared entirely around going where the evidence points, and people complaining about their ideas not being accepted probably just don’t have any such data.

foorp fo nedruB

That’s a reversed burden of proof, for those of you busy trying to translate it from Klingon or something. If someone comes along with a new product or scientific claim, you’re under no obligation to take them seriously until they’ve demonstrated that it works. You’re not obliged to prove that it’s completely impossible before making any kind of judgment, or give them the benefit of the doubt until then.

Homeopathy and astrology, for instance, are both claimed to work by mechanisms that seem entirely implausible, based on our current understanding of multiple areas of science. This doesn’t prove with absolute certainty that nothing will ever come of them, but nobody’s interested in doing that. You can’t absolutely prove that my pet unicorn Hildegaard isn’t spying on you right now and telepathically reporting your every move back to me, but that doesn’t mean you need to treat it like a credible theory. These ideas all fail a number of basic tests for scientific plausibility, so until someone actually produces some convincing, repeatable, rigorously scientific results, you can ignore the crackpots continuing to promote them. If you’re not being presented with any data, but still being told to “trust” this idea, or told that your skepticism isn’t appropriate or justified, then you might just be looking at a big ol’ steaming pile of pseudoscience.

Impedimentarily obfuscatory collocution

As is so often the case, things go much more smoothly and productively in science if people know what the hell you’re talking about.

Science has jargon in almost every field, and this is fine and necessary. Physicists, for instance, often talk about neutrinos, and quarks, and bosons, and fermions, and many other terms not in common usage. But this doesn’t make them needlessly technical and opaque; they’re just labels for things which don’t often come up in discussion outside of particular scientific circles. Someone not familiar with the sport of badminton might not know the word “shuttlecock”, but they could probably get to grips with it and use it appropriately after being shown what one is. They wouldn’t insist on everyone avoiding the technical talk and referring constantly to “the ball thingy with the feathers on”.

Expecting physicists to go without these terms would be like abandoning the words “man” and “woman”, and attempting to describe people’s gender in terms of factors like their shape, or anatomy, or whether they smell nice. It doesn’t add anything to transparency, or simplify the discussion at all (in fact, quite the opposite).

Corporate jargon is an endlessly fun object of mockery, even though a lot of the phrases involved seem to be perfectly acceptable idioms communicating useful concepts that our language doesn’t otherwise account for. People usually start taking objection when it’s not really being used to communicate anything – when pointlessly verbose and grandiloquent language is used as if to deliberately obscure the meaning. (“Synergy” can actually mean something, but it can just be something to say if you want to sound business-savvy.)

A common sign of pseudoscience is to see lots of technical language being thrown around which looks plausibly scientific, but can’t be consistently reconciled with any other scientific field, or which doesn’t explain its jargon expressions in more mundane terms. SkepticWiki has some good examples, including “quantum biofeedback”, “Counter Clockwise Molecular Spin of Water Molecules”, and “total consciousness of the universe”. There’s also a lot of technical-sounding variants on the ill defined concept of “energy”, as mentioned above. This sort of thing should raise your skeptical hackles still further.

I’ll add more in future, but this seems like an adequate start.

Read Full Post »

The world’s been around for a while. And although there’s no shortage of cool stuff in it for us to look at, some people aren’t content with being limited to everything that’s around now. They reckon that some of the stuff that happened “before now”, in a period of time experts refer to as “the past”, might also be quite interesting. To learn things about the past, and what exactly went on there, we’ll have to have some way of extracting this information, from things we can look at in the present.

Sometimes this is simple. If you want to know what was on the mind of any given emo poet in the last few years, there’s LiveJournal. This and many other equally vital pieces of information are stored, regularly and reliably, and provide an easily accessed insight into yesterday, yestermonth, and beyond. There are also news archives, parish records, and diaries kept by rather more notable historical figures than the emo poets of the 21st century, to give us a more rounded view. Sometimes these can be unreliable sources, riddled with political and personal bias (that Adrian Mole clearly can’t be trusted, for one), but they at least provide some insight into what the past was generally about, even if we can never totally avoid the danger of inadvertently buying into someone’s own line of bullshit.

But sometimes we want to know about things that nobody wrote anything about, or passed down any credible verbal stories about, or filmed on their camera-phones. One important part of this is finding out how old something is, for those times when you don’t also manage to dig up the diary of the guy who put it there. Dating historical artefacts is a massive and complicated area of science, embracing many fields of study, in none of which I am qualified to claim even rudimentary competence, let alone expertise. This, then, will be a brief description of radiometric dating, a broad and shallow summary of how it works, without too much detail just yet as to how we know it works as well as we do. There’ll be a few other articles branching off from this one soon, looking at some of the common complaints and objections raised to it, to the extent that my poor monkey-brain can cope with the intellectual rigour of it all.

So.

Up and atom

Before we can get into the meat of this topic, we’ll need to cover some basic particle physics. But you guys like reading lengthy essays on the internet about particle physics, right? I mean, porn can only hold your attention for so long before you start lusting for some hard science action, am I right? Well, if not, you can skip down to the next heading in bold, but I’ve written this bit now so I guess I’ll leave it here.

Good. So, physics. Broadly speaking, all the stuff that everything’s made of is itself made of three types of basic particles: protons, neutrons, and electrons. (Don’t worry about the dozens of others. It’s fine to simplify for now. There won’t be a quiz.) In an atom of any particular type of stuff, some protons and neutrons will be clustered together in a big dense ball (the nucleus of the atom), and some number of electrons will be floating way out around them (relatively very far, but still well under a billionth of a meter away).

Let’s pick one particular type of stuff as an example. Look at a pencil. The stuff in the middle that you write with is graphite, which is a form of carbon. Each atom of carbon is made up of those particles as described above: specifically, six protons and six neutrons bundled together in a ball in the centre, and six electrons circling around them1. That arrangement is what makes it carbon.

If, instead, you have just two protons and two neutrons in the middle, with two electrons orbiting, you get helium, the gas responsible for one of the most univerally hilarious phenomena known to science: making people’s voices go squeaky.

The numbers of particles don’t always have to match up exactly, like they do in those two examples. Sometimes there are more neutrons than protons, or very occasionally vice versa – but you can’t just throw any old mess of protons and neutrons into a nucleus and expect to make an atom. There are forces pushing them apart and pulling them together, kinda like gravity or magnetism pull at things sometimes, and so only some arrangements are stable.

For instance, the carbon I described up there has six of each type of particle. But that’s not actually the only way to make carbon. The number of protons is what defines what element a molecule is, so anything with six protons is carbon. You couldn’t have a nucleus with only those six protons, though, and no neutrons, because then there’d be a strong magnetic force pushing them away from each other (the same kind of magnetic force which makes your fridge magnets not want to get too close to each other), so it’d all fall apart. But if you put six neutrons in there as well, they provide a sort of binding force (I hope it’s clear that I’m still greatly over-simplifying all this) and hold the whole lot together. Because this particular type of carbon (one of carbon’s isotopes) has twelve particles in the nucleus (six protons, six neutrons), this is called Carbon-12. Carbon-12 is stable – the nucleus bit in the middle won’t ever just fall apart on its own – and around 99% of the carbon you’ll ever see will be like this.

Carbon has one more stable isotope, Carbon-13, which has seven neutrons instead of six in the nucleus. There’s still six protons (otherwise it wouldn’t be carbon), and six electrons (otherwise it would be ionised, which isn’t worth worrying about just now). This makes up almost all the rest of the carbon, the stuff which isn’t Carbon-12.

And then there’s one more type, Carbon-14, which has – anybody? Bueller? – eight neutrons. There’s very little of this stuff around on Earth – about one in a trillion carbon atoms are of this type – and unlike the other two, Carbon-14 is radioactive. It won’t just sit still being carbon, like its isotopes tend to do (and for which your DNA should be grateful), but over time it decays into different types of matter, because all the stuff in the nucleus can’t quite hold itself together indefinitely. In this case, Carbon-14 will undergo what’s called beta decay.

All the people atoms, so many people atoms2

Beta decay means that, every so often, one of the neutrons in an atom of Carbon-14 will suddenly transmogrify into a proton, and emit an electron (which would make your Geiger counter click, if you happened to be waving one around)3. Because of this extra proton, it’s now an atom of Nitrogen-14, and not carbon any more. This could happen at any moment, depending partly on the stability of the atom in question. Some radioactive stuff will tend to linger for years; other elements will decay into something else much more quickly. How long the radioactive stuff stays around is determined by its half-life.

The half-life of a radioactive element is the amount of time in which you would expect half of a sample of it to have decayed – or, the time after which the odds are 50/50 of any particular atom decaying. The reason I use words like “expect” is that it’s still random, so you can never be certain exactly when your Geiger counter will click, but it’s guided by a measurable process.

Time for a dubiously appropriate real-world mathematical analogy. Imagine you’ve got a thousand coins laid out on a table, all currently turned to heads. You flip them all once, and get rid of the ones that come up tails. You’d expect about half of them to go – maybe not exactly 500 out of 1000, but pretty close, because that’s the average you’d expect when the odds are 50/50 either way. Radioactive decay is like that: after a certain time (one half-life, or one round of coin-flips), you expect half your atoms to have decayed, on average. Flip the remaining 500-ish again, and about half will go again, one further half-life later, and so on.

Now, if I know that this is what you’re doing, I can figure out how many times you’ve been through this process of flipping all the coins and removing the tails. If I know you started with 1000, and now there’s around 125, I can be almost certain that you’ve done it three times (because when you take 1000 and halve it three times, 125 is what you’d expect to end up with). In a similar way, if scientists know how fast some radioactive stuff is decaying, then by looking at how much of it there was and how much there is now, they can tell how long it’s been decaying for, and thus how old it is.

The half-lives of radioactive stuff range from tiny fractions of a second, to billions of years. So, onto some specifics of how we can use this to actually work stuff out.

All we hear is, radiocarbon

To a lot of people, any way of finding out how old some really old stuff is, is basically “carbon-dating”. And by “a lot of people”, I mean me until a few paragraphs ago. It’s actually only one of many ways we can use radioactive decay to measure how old something is, but it’s a useful one, so let’s focus on that first.

Most carbon is Carbon-12, as you may remember from that bit you probably skipped over. A very small proportion is Carbon-14, which has a half-life of around 5,730 years.

We’ve found this out to a reasonable level of accuracy (the error bars usually given are about 40 years either way), basically by just taking a sample of C-14 atoms, and watching how fast they decay. Fortunately we don’t need to wait an entire half-life to get a useful answer, because unlike the individual coin-tosses in the example earlier, radioactive decay is a continuous process – so, if half of a sample will have decayed after 5,730 years, a much smaller (but mathematically calculable) sample will have decayed after a much shorter, more easily measurable time.

It might sound like only a really, really tiny amount would decay in a short enough time to measure, if it takes millennia for half of the stuff to go, and that it could therefore never be measured with any useful accuracy. But atoms are really, really, really small, and a tiny fraction of a gram can contain billions of them, easily enough to get a meaningful measurement of how fast the stuff is decaying. So, we know Carbon-14’s half-life, to within a low (and also well known) level of certainty.

So now that we know the rate of C-14 decay, we just need to know how much of it something started with, and measure how much is left now, to tell how old it is.

Plants take in carbon dioxide from the air in photosynthesis, some of which will be C-14. Other living things that don’t photosynthesise (such as “animals”, in technical biology jargon) tend to eat these plants (or other animals, with plants somewhere further down the chain). So every living thing is continually taking in and excreting some C-14, mixed in with all the rest of the carbon in their diet. The overall level of C-14 in their bodies stays fairly constant, depending on how much of it is in the air they’re breathing, and the stuff they’re eating.

Once they’re dead, though, this cycle comes to an abrupt halt, and the C-14 inside them is left to just radioactively decay. Because it’s only after the moment of death – when they stop breathing and eating other things with carbon in – that the amount of C-14 begins to drop off rather than being continually topped up, we can estimate how long ago the poor sod whose carbon content we’re poking around in died.

That’s basically carbon dating. It’s useful, but obviously limited. It’s not generally used on samples older than 60,000 years, since after more than ten half-lives or so, there’s such a small proportion of the original C-14 left undecayed that it’s impossible to tell with much accuracy how long it’s been decaying. Also, not everything even has any carbon in it to measure. But potassium-argon dating can be useful with rocks upwards of 100,000 years old, and uranium-lead dating is what you want if you’ve got some zircon that’s been lying around for billions of years, and there are many other similar techniques. The basic priciples of radioactive decay are the same in each case.

I wish to register a complaint

Unsurprisingly, not everyone’s happy with of this. Many people disagree with the conclusions of radiometric dating. Just as unsurprisingly, a lot of the complaints stem from a misunderstanding of how science works. In particular, the detractors of radiometric dating methods tend to approach it with an all-or-nothing mindset, and assume that a single result that seems unreliable, or any sign that it doesn’t work perfectly in all circumstances, must nullify every aspect of the discipline.

This drastically oversimplifies things; obviously we should be on the lookout for faulty results and anything which calls these methods into question, but it’s not implausible to suggest that we might be able to understand its particular shortcomings, and come up with a more limited (but still useful) system in which the results we get are still valid, and can be shown to be consistent, replicable, and entirely scientific. The pen I’m currently holding in my hand isn’t plummeting straight down into the Earth’s gravity well, but that just means we need to understand Newton’s laws in context, and be sure of how they can or can’t be applied, if we want to avoid being reckless and leaping to ridiculous conclusions. The scientists who developed these methods have had plenty of time to figure out their shortcomings.

The people who have a fundamental problem with the entire field of radiometric dating, though, often seem less than clear on what errors led to the supposedly faulty conclusions. For many of them, I suspect their doubts didn’t originate with a flaw they uncovered in the scientific methodology being used – but strict Biblical doctrine implies that the world is no more than 10,000 years old, so if that godless, immutable behemoth of Science somehow says that some things have been around for millions of years, then it’s obviously gone wrong somewhere. The details of where these mistakes have been made is rarely given quite so much thought – it’s only obvious that they must have been made somewhere, because the results disagree with the inviolate axiom of Biblical infallibility and Jesusy goodness, on which their world turns.

When fundamentalists are trying to protect their dogma from an onslaught of pesky facts, the most useful pseudoscience tends to concern theories at a slight remove from what’s commonly understood and accepted by laypeople. Nobody wastes any time denying that elements consist of a nucleus of protons and neutrons, and surrounding electrons, just as there’s no real dispute these days that genetic information is passed from living organisms to their offspring by DNA – these are things we all kind of understand, and they don’t threaten anyone’s ideology, so it’s universally settled that we’ve got these things more or less nailed. (This is always subject to change if new data arises, of course, but we’ve observed enough by now that we can be pretty confident we’re on the right track.)

But the controversy comes when the science gets a bit trickier, the concepts less easily grasped by anyone who hasn’t spent time studying them, and the implications less comfortably reconciled with the dogmatic claims of belief systems. Because of this, fields of study which are equally well established and supported by evidence start getting labelled as “controversial”, and it can easily seem like some scientific theories are much weaker than in fact they are. You won’t find many evolutionary biologists who think that the basic idea of evolution (that life on Earth evolved through a process of Darwinian natural selection) is any less likely to be true than the fact that our genes carry our genetic information, but it’s a much simpler task to spin one as a “controversy” than the other. The evidence supporting it is overwhelming, but a lot of it is harder to understand, so it may be less intuitive to accept “Because it’s obviously true” as a reason why the scientific community seems to be so unanimously behind it.

Of course, simply labelling anyone who disagrees with the majority view as an ideologue who doesn’t understand the subject matter, and ignoring their arguments, would be a colossal logical fallacy. If these “scientific” objections are as out of touch with real science as all that, then even I should be able to explain the flaws behind some of them. But it’s taken far too long already to put this together, so I’ll cut this off early, and talk about some of those problems in separate articles soon. In the meantime, you might find enlightenment at the Radiometric Dating Resource List, or these articles by Dave Matson, or the ever-invaluable TalkOrigins, or any of the other articles linked to further above.

1Though, they don’t really circle in that traditional pattern, like planets orbiting the Sun. Physicists, don’t send me emails about electron clouds.
2Half-life. Like Parklife. It’s a pun. Don’t worry about it.
3I know, I’m still simplifying a great deal here. Physicists, don’t send me emails about neutrinos.

Read Full Post »

After the roaring success of similar campaigns for both Tibet and Willy, it’s now time to discuss Free Energy. (Ha.)

The idea of free energy is pretty much what it sounds like. It doesn’t just work in the “free cable” sense of tapping into someone else’s pipeline, but rather by actually creating new and usable energy, often literally from thin air. It’s like taking candy from a baby, then selling it to another baby, then stealing it back again, and repeating the pattern indefinitely.

These kinds of machines which promise ultimate power at low, low prices are still a recurrent phenomenon, and make for pretty big business. Perhaps it’s not surprising that people regularly claim to have invented or discovered some device, mechanism, or physical process which would render that whole fossil fuel problem moot. It’s an appealing notion, to have something which could power itself and let you siphon off the overflow, storing and using all this new energy as it spills out from… somewhere. Unfortunately – at least, if you’re living under Homer Simpson’s roof and obey the laws of thermodynamics – the Universe places an inconvenient embargo on the whole idea.

Although there might seem to be many ways you can “get” energy where there wasn’t any before, you’re never really conjuring anything out of nowhere. If you light a match, you’ll be releasing heat (thermal energy) that wasn’t around before, but it comes at the cost of the resources you’re burning. The amount of energy released in the flame exactly matches the lost energy that existed in a different form in the chemicals that made up the match.

Calculated in this broader, chemical sense, energy isn’t something that can ever be created or destroyed, but only transferred from one state to another. If you burn some oil for energy, you can’t keep the oil and burn it again. If a system is kicked into action by something falling, like water in a water wheel, then it would take at least as much energy as you got out of it if you wanted to raise the stuff back up to its original height again. (This is why Wikipedia’s gallery of perpetual motion machines are all doomed to failure; a system can’t, by itself, generate more energy than it uses to keep itself going indefinitely.)

Them laws of thermodynamics ain’t no slouch, incidentally. The first one – pretty much the “no conjuring” rule as described above – is among the most solidly convincing theories in modern science. If you throw that out, then a whole lot of really useful physics goes with it. Centuries of sophisticated learning and understanding shouldn’t be scribbled over with the first new and crazy idea to come along with Earth-shattering claims.

However cunningly you try and arrange something with magnets to keep propelling itself around on its own metaphorical steam, it can’t be done.

If a flywheel is spinning, and seems happy to keep on doing so pretty much indefinitely (some are set up with such low friction that their rundown time is measured in years) then that’s all well and good, and may be a useful way of storing energy, such that it can be usefully transferred from one form to another. But to get any energy out so that you can use it, you need to let the flywheel push against something else to power it – and in so doing, you’ll be exerting a similar push against the spin of the flywheel, causing it to slow down from the friction. The energy you get out can never be more than the energy you had to put in to get it spinning that fast in the first place.

If you want to run a car on water, you’re going to have to do something more than Stanley Meyer did, because if all you’re doing is separating water into the oxygen and hydrogen that it’s made of, then burning the hydrogen and oxygen to make water again, you’re never going to get any more out when it burns, than you needed to put in to separate them. You just go round in circles, and no work is being done.

Unless, y’know, you’re throwing out almost all of physics again. That site describes the problem of how do it “economically”, and says that by traditional methods the car “could not recharge from the process quickly enough”, but makes it sound like levels of energy input and output are two separate issues to be improved upon. They don’t seem to mention the thing about needing more than 100% efficiency, which makes recharging from the process “quickly enough” about as likely as being able to run fast enough to overtake your own knees.

Creating energy this way would be like magicking water into existence by taking some water, freezing it, then melting the ice, and experting to find more water than you started with. It’s not going to get you very far. You don’t get something for nothing.

Admittedly, not every device needs to get something from nothing, while still being intended to revolutionise the world of making stuff go. Wikipedia lists several resource-consuming machines which provide apparent perpetual motion, like that little drinking-bird thing that helped Homer keep the power plant safe while he went out to buy a muu-muu. (Huh, lot of Simpsons references in this entry. Well, two.) The way those work is surprisingly sophisticated, and there’s some fascinating science behind subtle sources of energy like ambient temperature gradients, or pressure from photons.

This isn’t any kind of a loophole around the laws of thermodynamics, but maybe you don’t need to circumvent them, if energy can be grabbed from plausible sources, in such quantities that it might seem effectively free to us. I can’t rule that out, but the problem then comes back to the perennial sticking point: if you want to be taken seriously, publish some damn science. If you actually do an experiment, and find something to support your claims, and then tell other people what you did so that they can try it too and see if you’re still right, then vindication surely awaits. But what you’re saying sounds unlikely, and it sounds very similar to some other unlikely-sounding things, which are demonstrable nonsense and which break many well established laws of science. You’re going to have to actually show us something impressive.

Of course, there are always reasons why they can’t do that just now, often relating to the various conspiracy theories in place to suppress the knowledge of this world-changing technology, and preserve the status quo for those who find it profitable. I’m not aware that any significant evidence has ever been presented that this is actually happening – of course, this could mean that it’s all been covered up, but it could more simply mean that it was never there. (More on conspiracy theories in general over here.)

I’m sticking with my “publish some damn science” argument. I don’t see how data from every scientific lab could be kept out of every respectable scientific journal – those scientists and journals would be fascinated to learn anything new that’s well supported (that’s kinda what science is, after all), even if some politicians and oil magnates wanted it kept quiet.

But when established science is so strongly indicative that you’re full of shit, in a field with a history of fraud (and other business practices which should maybe raise a suspicious eyebrow), we’re going to wait for some actual evidence before accepting that you, unlike the conmen and failures who’ve gone before, really have revolutionised everything we understand about the Universe. And while everybody seems cagey as to how these things are supposed to work, and what tests might be done to find out whether they really do, and while Reuters reports credulously on supposed new developments, we’re going to keep doubting that The Man is keeping you down.

Science loves discovering things which it can’t explain, and which shatter old paradigms. Find us some actual evidence, or even just show us what’s going on and let us find it, and the scientific and skeptical community will totally be on your side. Stop holding press conferences and asking for more and more research money. It’s not working.

Read Full Post »

Tomorrow, September 10th 2008, the Large Hadron Collider will be switched on.

More precisely, tomorrow a beam of particles will (we hope) be circulated throughout the entire collider for the first time. The first particle beams were initiated about a month ago, to calibrate the whole mechanism to an accuracy of under a billionth of a second. It’ll be another month or so before the first “high-energy” collisions take place, when individual protons (of which your body contains around ten billion billion billion) will be accelerated to over 99.9999% of the speed of light, and then smashed into each other.

To do this requires over 1,600 magnets, and about 96 tonnes of liquid helium to keep them less than two degrees above absolute zero. Once the protons are at top speed, they can traverse the 17-mile circumference of the collider over ten thousand times in a second. They also weigh 7,000 times more (or, rather, have a mass 7,000 times greater) and perceive time itself 7,000 times slower (inasmuch as a proton can “perceive” anything) than if they were just sitting still, due to some freaky Einsteinian shit.

When these two particles, each about one millionth of one millionth of a millimetre across, smash into each other, some unfathomably clever people will peer closely at what happens, and use the information they gather to work out things like what makes stuff have gravity, how many dimensions of space there really are, and what the universe was like 13.7 billion years ago or so, around a trillionth of a second after every piece of matter in existence was concentrated in an infinitely dense point.

Fucking hell.

I was planning the bulk of this entry to be a rant about people who think the world’s about to end, but I can’t be bothered. Every day for the last couple of weeks, a dozen or so people have been finding my entry Nostradamus Potter and the Deathly Hadron Collider. The search terms “nostradamus all should leave geneva”, “10 september 2008 black hole nostradamus”, “swiss collider nostradamos”, “nostradamus prediction on lhc”, and several others, all very similar, have led people there just today. But I’m much more interested and mind-boggled by the facts about what this machine is, and what it can do. And there’s no conceivable threat based on any actual scientific ideas. I think the people who’ve built this damn thing actually understand how it works, and what it’s going to do, a little more clearly than the people whose protests amount to “Science is scary!” and “Did someone say black holes? Oh noes!” and “But what if they’re wrong?!?”

It seems like a threat because the unknown is scary, and apparently very very small things are scary too. Talk about nanotechnology, and it’s hard to go long without making the mental leap to the idea of tiny robots getting out of control, turning everything into tiny copies of themselves, or some such. It’s an effective horror trope, but worrying about the whole planet being destroyed because you’ve heard someone mention something about black holes (which is as complex as most people’s worries get) is about as useful as using disposable surgical gloves to take your laptop to be disinfected with bleach because it has a virus. Smarter people than me have explained this. Also, Brian Cox thinks you’re a twat. This cartoon is about as likely. You can all stop threatening to kill the scientists who are orders of magnitude cleverer than you and trying to figure out how the Universe works now.

To infer the existence of the Higgs boson would be an awfully big adventure.

Read Full Post »

Yes, now it’s easier than ever to write disturbing fanfic with slash pairings of your favourite theoretical models of the physical laws underpinning the universe.

First there was Physical Theories as Women, and the corresponding Physical Theories as Men. And now…

0. Newtonian gravity is Ron.
Solid, dependable, good long heritage.
It has its limits, but is surprisingly powerful.

1. Electromagnetism is Snape.
You must master E&M, but so many have irrational fear or hatred of it.
It leads to deep unification and glimpses of fundamental symmetries, and is strangely beautiful yet powerful.

And so on through to Hermione as string theory, and a special mention for Voldemort’s Aryan physics. It’s brilliant, but it may end up revealing more about the author’s ‘shipping tendencies than the physical theories in question. By this system, Snape is “strangely beautiful”, Harry is “apparently orthogonal to [Snape], yet incomplete without [him],” and Draco is Snape’s and Dumbledore’s love-child. Oh, and Hermione “may contain all the other fields within [her]”. All of which is just adding fuel to many scary and confusing fires.

Read Full Post »

%d bloggers like this: