The following was edited on 19 April 2011 to replace a post published on 10 April 2009. The original was harsher and caused offence. I deleted it, but was asked to repost it, so here it is in edited form. I hope it causes no further offence, but if it does, hey, you can’t please all the people all of the time, and they really have to get over themselves.
Since posting it originally, DDWFTTW has progressed substantially. I dropped in from time to time, but haven’t kept up with it. There’s been a ride-on version called Blackbird that set the benchmark world record at nearly three times windspeed. I understand the pissing match continues. There’s a really good troll called humber, and few can resist a really good troll.
My goodness, how time flies when you’re having fun. What is it, half a year since I posted here? What was my blog about before?
It was going to be all about philosophy, especially my conversion (or awakening) from buddhism into the light of reason. Then I just got bored with the sound of my own typing, and the next thing I knew I was reading about a strange little brainteaser on the JREF forum (and everywhere else, apparently), the question of whether it’s possible to build a vehicle that goes directly downwind faster than the wind (DDWFTTW) powered only by the wind, “steady state” (which means not just as a passing burst, but settled at that speed).
There is so much to this, which I’ve been immersed in since at least December, both as a physical phenomenon and a social one, that it’s really hard to know where to begin.
I learned a lot in these few months. I learned how a little cart with wheels and a propeller can go directly downwind faster than the wind. I think…
…because I also learned how wrong I can be about such things. Even now, I’m not sure, and keep thinking I’ve spotted a flaw. I spent the first few weeks very sceptical about it, and even got to the point of saying that I’d eat my hat if it was true, but the last few months I’ve been 99-point-something percent convinced that it’s not only true, but has been demonstrated both outside and on a treadmill. (They let me off with the hat thing.)
The “treadmill tests” have been a big part of the debate, and it was something of a revelation – or a rediscovery – to learn about equivalent frames of reference in mechanics, how useful they are, and how philosophically interesting. Velocity, as we kept insisting to the nay-sayers, is relative: hence, a cart being blown by a steady wind over the ground is entirely equivalent in its local conditions (i.e. for a Directly Downwind cart running there) to a treadmill belt going backwards under the still air of a room. Thus, if we put such a device on a treadmill and it moves forward in still air, that is equivalent to it moving across a piece of land outside blown by a steady wind. It’s also a little easier to do the tests, and to guarantee that this is a steady wind (if you close the doors and windows and don’t wave things about too much).
Writing the above, I’m well aware that many people will laugh at the idea, or just read blankly wondering what on earth I’m talking about. How can still air have anything to do with a steady wind? How can a cart going forward in it prove that it would go faster than the wind outside? Well, answers to that are plastered all over the net, but in brief, it is so for all such situations where the relative velocities between the parts remain the same: you can shift all of the velocities numerically one way or the other, so that a moving wind becomes still (in this case) as long as the “road” is now shifted in its velocity also, by the same amount. The different “zero velocities” are called inertial frames of reference, and we’ve known that they are equivalent for several hundred years, with no exception having been found ever. These things are so long and fully established that they are considered basic laws.
Complications exist. With a treadmill, there are some things one can observe that don’t occur if you literally translate the motion to an outside scene. On the ground, the ground continues to stretch out as far as the eye can see, and is a globe and comes back around the backside. If you translate the treadmill with a cart on it back to a piece of earth, you’d have to construct a smaller stationary piece of earth with the cart on, and great areas on all sides moving forward. But such differences as exist are ones of scale – they have the potential to alter the result, and must be studied, IMHO, and shown to be negligible, rather than just ignored, but in this case they do seem to be utterly negligible.
As with many brainteasers, once you see it, it’s easy to keep seeing it, and your earlier objections fall away. However, I’ve never come across something for which my personal mental objections kept rising and rising, each time being shown to be unreasonable. As I say, I still have the occasional doubt.
The social side of it has been immensely interesting as well, almost more so than the physics. There are two guys, one of whom goes by the username of spork (and at youtube, spork33), and his mate, “ThinAirDesigns”, or “JB” as he signs his posts, who are heavily into this and promoting the idea in dozens of forums, building carts, testing them and posting the video, teaching the physics, arguing with nay-sayers and trolls, and one wonders how they manage to hold down their jobs (and, apparently, go flying or paragliding at the weekends, too).
I have recently fallen out pretty badly with spork. Our relationship was stormy from the start. I was a bit naive to expect that I could blather on about the machine from a position of relative ignorance and be heard with endless patience. There were some misunderstandings, and I think I pissed the guys off particularly by raising objections again after announcing that I understood it. I have the feeling it seemed like I was being deliberately awkward, and spork seemed to react as though he felt betrayed. I was genuinely just working through my questions, but I might have put them rather forcefully, as positive opinions rather than questions. I found spork and JB – and still do – highly defensive, but they were under attack by a constant stream of sceptical newcomers and hardened trolls.
I had a final fight with spork over his insults on the RichardDawkins.net forum (towards others, in fact, not me). These may have been in response to earlier insults from the other, but were to my mind beyond the pale. I reported one of his posts to the mods and things went from bad to worse.
Someone I have made a better friendship with is Recursive Prophet. This was a little surprising as well, because he did strike me as an unlikely friend at first. I didn’t trust him. He was too complimentary about everyone, and then occasionally seemed to stick the knife in about something, or seemed not to respond to answers to questions he’d asked, just repeating them. He got a lot of things wrong, especially his analysis of “humber”, the uber-troll of the whole downwind debate. But he – “RP” – turned out to be a genuinely nice guy. As with most of us, his biting remarks were in response to being rubbed up the wrong way by others.
This is a big lesson – one that a lot of people are learning through internet discussion – the way we go around with a mental picture of ourselves all squeaky clean and wonderful, only ever being a bit short with someone who deserves it, after much provocation. Unfortunately, we’re all doing much the same. Some are a little more patient and forgiving and “relativistic” in their outlook than others, and they tend to recognise that ubiquitous human problem and sometimes manage to apply it to themselves (I’m thinking of my good self here, obviously, tee-hee), while others have no idea how different our perspectives are, just believe that things are correct however we see them and if anyone disagrees, they’re obviously wrong.
Spork, for instance, said that he never gave insults that weren’t in response to an insult by the other. I tried to suggest that the other might also see it the same way from their side, that our little niggles and irritations can grow gradually, each adding to the severity of the response, always thinking that they are giving a reasonable and measured reply, or perhaps trying to warn the other off – a sort of “I have caught on to the fact that you’re getting at me and if you don’t stop, you’ll get more of this incredible wit” – while the other reads that as “your last warning is ignored, and I insult you further”.
Anyway, I decided to write here not to slate spork or talk about the physics of downwind travel, but just to celebrate my new friendship with Recursive Prophet. RP is quite sarcastic about the spork-JB program now as he exits from it [er, what, again? – he’s still there! – ed.] and I’m pretty sure that he’s seen on the forums as a troll and a troublemaker, talking shit and being aggressive. Some of that criticism may be deserved, but he’s a relativist; for the most part he recognises that our beliefs and views are separate from us, and thus he expects people not to feel any resentment about his disagreement. Within the scientific/engineering community this is often poorly appreciated: facts are highly prized, and facts are facts, not opinions, so if there’s a disagreement someone is right and someone else is wrong.
The difference between “that’s a stupid statement” and “you’re stupid” – which is the watershed on a lot of forums – goes deeper than just a handy distinction for separating dispute from insult. One example that came up is “liar” and “a lie”. JB – I think it was – argued that if someone has clearly been shown to have told a lie, then they are by definition a liar, so calling someone a liar should be an exception to the no-insults rule.
But to someone who understands a bit more about relative viewpoints, or just has a little deeper understanding of psychology and philosophy, this argument doesn’t stand up to scrutiny. Firstly, whether something is established as true is a doubtful proposition (due to the self-referential quality of language, if nothing else), and secondly, it is generally considered unlikely that any human being has not lied at some point, so by the definition we’re all liars.
Logically, this doesn’t mean it’s an offence to point it out, but it’s a bit like saying to someone that they are “nuclear waste” (as opposed to “stardust”), or “somewhat evolved slime” (rather than “a human being with a brain that is an example of the most complex entity in nature”). Clearly, calling someone a liar has meanings of greater social significance than saying that the statement they just made was untrue.
Similarly, some were angry when RP called spork a “fundamentalist”, and a few posted to say that the word had very offensive connotations, but RP posted a standard definition of the word, from which it was clear that belief in the tenets of classical mechanics, or of science, without any doubt, could be a kind of fundamentalism. Again, it could be said that it had greater social significance than the definition, like “liar” does, or one can observe the accuracy or otherwise of the meaning that the speaker intends to convey, and if it is not known, ask more to find it out.
One can take offence with a semi-conscious image in mind of a suicide bomber, or one can try to learn what another human being is trying to get over. Understanding what the other is trying to get over has to come before working out whether we agree or not; deciding how to respond should then come even later. What too many of us do too much of the time is react to communication at an autonomic level: a word triggers a gut reaction as it filters through the unreflective lizard brain we all still have below the grey matter.
Of course, in the world of science, it is often argued that the facts are pure and simple, established beyond doubt, and all that relativistic nonsense should be kept in its social context. The next minute, the same people might argue that they’re not fundamentalists in outlook, because science is about holding theories reasonably tentatively, being ready to doubt them and overturn them in the light of more empirical evidence or powerful theory. There is a healthy balance of these things, which I feel does defeat many of RP’s arguments for relativity (where they apply to laws of physics). On the other hand, too many scientists push the boundaries of the absolutism of science, or they fail to appreciate the postmodern insights into language that make such statements as “I’ll find the quote where you said it”, or “I know exactly what you’re saying and it’s just plain wrong” childish extravagances or denial.
A perfect example happened in my last few days’ involvement, when I tried to help spork and another poster, “asymptotic freedom”, to recognise that they were misunderstanding each other in their discussion. Spork said there was no misunderstanding, but AF acknowledged it as a “mis-communication”.
If anyone was paying attention through these months (for some, years) of debate, it would be clear by now that we often take a simple statement or question as though its meaning is totally unambiguous – “does a balloon track the wind?” for instance – only to discover that each of us may assume different bounds and relevant conditions, and we might set off arguing about the answer and not realise we’re discussing two different things. One way to try to avoid that is to establish the correct meaning at the beginning, but some details may only come to us as we investigate the question, and if we’re already pissed off we’ll not be free to discover them with equanimity. We get too invested in having the right answer already, and our discussion with others, instead of being a mutual discovery, becomes a fight. Science, of course, is full of it.
The “pissing match”, as spork called it, of DDWFTTW was amazing fun at times and brought out some people’s best humour. I’m sure everyone learned a few things, and a lot of people learned a lot of things.
I nearly got to the point of wanting to study mechanics at university or something, although I’ve backed off from that since. I know I can’t get my head round maths problems quite the way I used to, and there are other things that interest me more.
As an ex-therapist I’m aware that I often have unconscious motives for the things I do, and I suspect that all this involvement in a physics problem was to give me a break from my own pressing personal problems, and I think I’ve come out of the other side now, clearer of the answers to those life questions. I was taken down-life faster than the life, while my unconscious sorted out the mess that I was only making worse by worrying about it.
As Spring springs, I’m gearing up for getting a new motorcycle [yep] and starting work on getting a book published, which is almost finished in draft form [nope]. I also intend (when I’ve got a new laptop to replace my desktop machine[yep]) to use the space freed up in the study for recording my music [nope], something I’ve neglected for years[yep]. I hope to blog a bit more frequently[nope] and on a wider range of subjects in future[nope].
In the meantime, one of my new pleasures these days is listening to RP’s voice mail most mornings – it’s like my own personal Letter from America – and sending mine to him. It’s down to his enthusiasm for that medium that I got into it. Thanks, RP.
It was weird at first, but I quite enjoy it now. Talking in a 2-way conversation on Google Talk is slightly more difficult at the moment, because I haven’t got used to the dropout that happens as each of us tries to talk – I guess it’s just one channel – and because he talks most of the time 😉 but voice mail is a revelation. Being able to talk to someone is quicker than typing emails, even for a fairly quick touch-typist like myself. Like an email, each participant can pay attention to it when they have time – also an important consideration when there’s about 8 hours between us, me in the UK and him on the “left coast” of the US. It’s one of the best forms of therapy, and has some interesting features in common with traditional forms of therapy. You’re talking to the other, knowing that they will listen (and, if it’s a good friend, understand and be sympathetic), but they don’t keep interrupting with “helpful suggestions”.