Brian Clegg
Appearances
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
It's about the way that light interacts with your veins. It's quite separate from the colour of the blood in them. Colour is quite interesting. Sometimes it's caused by a pigment. So sometimes it's caused by the colour of stuff, but sometimes it's structural. So actually the shape of something can change the appearance or the way light interacts with molecules.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
If you look up at the sky, the sky is blue, but there's no blue colour. pigment in the sky. There's nothing up there that is blue. It's literally the way the light is interacting with the molecules of air. And similarly, when you see the blue veins in your arm, it's not that the blood in them is blue. It's the way the light interacts with the material that makes up the veins.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
The reality is that bumblebees don't fly the way you might think. So if you think of a bird flapping its wings, it's fairly obvious what's happening. It's flapping its wings up and down. That pushes the air down, effectively pushes the bird up as it pushes the air down.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
bumblebees wings move in a much more complicated way they basically almost act a bit like a helicopter in that they have a kind of curved motion and the result of that is they actually generate more lift than you expect from those little wings
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
The other thing about bumblebees actually is they look chunky, you know, compared with an ordinary insect, they look pretty fat, but actually it's still very light. So it isn't as dramatic looking, as dramatic as it actually looks to be. And the fact is there's no problem at all with bumblebee wings supporting bumblebees. In some ways, a more interesting example is kangaroos.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
Of course, it is genuinely true that kangaroos use more energy or appear to use more energy when they bounce along than they consume. They seem to be able to actually give out more energy in their bounces than they've consumed in their food. And the reason for that is it's a bit like the way a rubber ball works. You know, if you drop a rubber ball on the floor, it bounces.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
When I was young, they had these things called super balls, super balls that bounced really high. I don't know if you ever had one of those. And kangaroos are a bit like that. So when they hit the ground, it's not a case of all the energy they're putting into their muscles is wasted.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
It's actually more like storing up energy in a rubber band as they hit the ground and then it bounces off and they use up that extra energy they've stored away. So they can do what seem to be amazing things, even though in practice they're not breaking the laws of physics.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
It's another of those little, it's a little bit more complicated. We're oversimplifying when we say the speed of light is the limit. The real thing is the speed of light in a vacuum is the limit. So the fastest anything can go is the speed that light goes through empty space. but light can also go through other stuff. It can go through water, it can go through glass.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
And when it does, it slows down. So light goes considerably slower through water or through glass or another solid transparent substance. And when it does that, it's closed down sufficiently that physical objects can move faster than the speed the light's going. And there's something called Cherenkov radiation that happens in nuclear reactors.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
Have you ever seen a video of one of the old nuclear reactors that had water surrounding the nuclear pile? it glows blue. And the reason it's glowing blue is that little particles that are coming off out of the nuclear reactor are actually going faster through the water than the speed of light through the water.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
And that produces a kind of optical equivalent of a sonic boom, which produces this blue glow. So yes, it's true. The speed of light in a vacuum is the absolute limit. But if we just say the speed of light is as fast as you can go, it's not true if you're not in a vacuum.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
And the fascinating thing about this one is it was, if you like, a deliberate urban myth. So a guy who was in advertising and marketing produced a fake paper, effectively, saying that this was the case. And he used this to try to sell the idea that these subliminal messages would make people want to drink
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
more of a particular beverage or want to go out and have a hot dog or whatever and the fact is it just wasn't true there is no good evidence that these subliminal messages work but the fact is you know so many people have heard this that we still today in a number of countries for instance it's illegal to use subliminal messaging interestingly there are very subtle effects that do seem to happen as a result of it but what certainly isn't true is that it will suddenly turn people you know
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
into the urge to drink a particular drink or eat a particular substance.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
Certainly in the original, no. So it was totally fictional. It was made up, the original, that was written up. It never did happen then. Since then, people have tried it, either tried it as experiment to see whether or not it works, but also some people have tried to influence others by putting frames in this way. But as I say, all the scientific evidence is that it has very little impact.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
Okay, great. Thanks very much.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
The classic is the Empire State Building. It's typically struck, I think, about 25 times a year. In fact, there's even one guy that was a U.S. park ranger called Roy Sullivan, who's been struck by lightning seven times in his career, thankfully survivable.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
I spend a lot of time talking to people about science, and all too often what comes up is it's a bit more complicated than we thought, that science tends to be a little more complicated than we think about it. And what I'm looking at here, in a fairly light way, a fairly fun way, is...
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
areas where we think that science is different from the way it really is, or where we simplify it so much that actually we don't really understand what's happening. So it's just trying to open up a little bit. It might be urban myths, it might be folklore, or it might just be not quite getting the science right in what I hope is an enjoyable way.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
And it seems crazy to say water doesn't conduct electricity, but actually it's a really bad conductor of electricity. But what is happening is it's the impurities in the water that enable it to do that conducting. So if you take totally pure water, it's a really bad conductor. And sometimes there's little things like that, or for that matter, toast. Toast falling butter side down.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
You know this thing, you drop a slice of toast, it falls on the floor. It's always the butter side that hits the floor. Or is it? Can that really be true? And a number of TV shows have actually tried to demonstrate it's not true. But unfortunately, what they've tended to do is toss toast in the air, a bit like tossing a coin.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
But the reality is when you drop a slice of toast, you don't throw it up in the air like a coin, it slides off your plate or it slides off the work service. And they're just about the right height that when something slides off and starts to turn, it has enough time to turn
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
No, absolutely not. The actual water, literally pure water, H2O, is a bad conductor. It's a good insulator. But the fact is, almost all the water we deal with on a day-to-day basis, the water that comes out of the faucets in the bathroom, is water that has minerals in it. And that's a good thing on the whole. There's nothing wrong with that. It's not a problem.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
But these minerals are in the form of what are called ions. So they're basically positively or electrically charged, negatively electrically charged. And that means that they can carry an electrical current. And it's those impurities in the water that actually carry the current. And it is dangerous, of course.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
Yes, you don't want to play around with electrics when you're in contact with water, because on the whole, the water we experience isn't pure.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
Yeah, it certainly does. I think one of the reasons for this is, you know, lightning is probably the most dramatic natural occurrence that most people have experienced. You know, there are bigger things out there, more horrific things like earthquakes and so forth. But the fact is most people have experienced lightning. It's pretty frightening stuff if it's fairly close.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
And if you ever see an actual lightning strike where it hits a tree or something like that, it's very dramatic. And certainly, over the centuries, most people would not have seen lightning strike in the same place twice. And because of that, a kind of folklore built up around it. But the fact is, it does happen, and it happens a lot.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
Any one time around the world, there may be 20,000 lightning storms, thunderstorms happening. And somewhere where there's a nice, big, pointy thing, you will get more than one strike. So the classic is the Empire State Building. It's typically struck I think about 25 times a year and it has been struck as many as 15 times just in a single storm.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
The fact is lightning really does strike more than once on the same location but it's almost become a way of referring to something. So we don't necessarily literally mean lightning doesn't strike fires, but rather more metaphorically, it's not likely to happen.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
In fact, there's even one guy, there was a US park ranger called Roy Sullivan, who's been struck by lightning seven times in his career, thankfully survived them all.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
I'm not sure he's still with us, but when he was around, the kind of job he was doing, he was out there, out in the wilds a lot, out in places where you may possibly get struck by lightning more than most of us are.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
anybody who actually owns fish, particularly if you have a pond, knows instinctively almost that this isn't right. Because the fact is, Goldfish learn, for instance, that if you come to the edge of a pond in a particular place, holding something and sort of shaking it around, food's coming, and they come to you. They remember it. They do have a memory.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
But in science, scientific terms, it's been tested by training them, for instance, to go through mazes, and they remember how to do that. In fact, all the evidence is that the original three-second memory bit came from a commercial, an advertisement. that was done just humorously referring to this. And somehow it's become part of what we tend to believe.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
And it's handy for a joke, but it's not really something.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
It's a problem that you get in a lot of scientific experiments, actually, not just the anecdotes. Because if somebody is just reporting, say, how they feel or what's happened, we can't actually isolate what the cause is.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
Now, what you actually find in practice is that when people have said, oh yeah, the kids have got really excited, they've had lots of sugar, there is often some other thing going on at the same time. So, you know, take children to a party, Yeah, they get lots of sugar, they get really excited, but also they're in a party, so is it really surprising that they're getting excited?
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Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
There just is no good scientific evidence. When you treat it scientifically, which means you have to separate off all the different influences, put people in a controlled situation so that you can actually separate off what is causing something, there is no good evidence that consumption of sugar actually makes them hyper.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
That's quite a nice little example of the it's a bit more complicated than that. The Big Bang theory is a theory of how the universe works. grew from practically nothing all the way up to what we have today. And we think that has taken about 13.8 billion years for it to go from a very tiny, pretty practically nothing up to what we have now.
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Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
And the Big Bang Theory is very successful at explaining that. But we tend to kind of associate it with literally the beginning of everything. And that's the one thing the Big Bang theory doesn't do for us. It doesn't actually explain why or how the universe came into being initially. That very first start, it has to already have, if you like, the laws of physics have to be there already.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
It doesn't explain where they come from. And the actual initial start of the whole thing requires, if you like it, to be there already for it to then start expanding. So it's not quite made it. And the other thing about it is we have a problem just seeing back that far. Now, the universe is really quite generous to us because light takes a long time to get to us from very distant places.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
So the further out you look in the universe, the further back you see in time. And we can see back until maybe 300, 400,000 years after the beginning. But beyond that, we can't see because the universe wasn't transparent before then. Light couldn't get through it. So what that does mean is that those first years, we struggled a little bit to be sure exactly what happened then.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
And certainly the Big Bang doesn't give us any insights of the initial beginning. So it's just a slight tweak, if you like. It's a great theory. It explains a lot. It gives us a timescale for the universe. But what it doesn't do is say how the universe came into being.
Something You Should Know
Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
Blood is red because of haemoglobin. So there's substance in the stuff that carries the oxygen around the body. And that haemoglobin does contain iron. And so it's quite easy to get a little bit confused and think, OK, well, iron usually makes things reddish. So rust is iron oxide. It's an iron compound. Mars looks red because there's a lot of iron in the surface.
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Science You Believe That Isn't True & The Story of The Lie Detector - SYSK Choice
So we tend to associate iron and redness. But it happens, the reason hemoglobin is red is actually due to the shape of the molecule, the way it interacts with light. It's nothing to do with the fact the iron's in there. So that's one aspect of it. It's not actually caused by the iron. And the other thing is the blue blood thing is not about the color of the blood itself.