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  • Yeah, if we just look over here down in the valley, there is where, sir Nous on da the S P s collider provides the initial protons and from those initial protons, they then lead to the generation of the neutrinos on those neutrinos.

  • Then fly off through the mountain range through the mountain roads there and over to another set of mountains in Italy.

  • Gran Sasso Mountains.

  • It's amazing to be here.

  • And just you suddenly realize you can talk about it all you like in a room.

  • And you think, My God, that's shooting straight through that rock over there.

  • What happens when you, Trina shit rock?

  • Nothing, absolutely nothing.

  • That's the beauty of neutrinos.

  • And the only interact through the weak force.

  • The weakest of evolve A of of all the forces, electromagnetism, strong and the weak.

  • And the Andre just don't even notice the rocket.

  • All its is.

  • If the rock might be a bit of fog that they're just going through.

  • And of course, the exciting result that they was.

  • It was announced a few months back, I think, in September of 2011 was that the when they took the timing of the neutrinos that were created and detected that created here just outside of of CERN and then detected in the Grand Sassa Laboratories, worked out the distance, and they knew the time, and they worked out the speed.

  • The velocity of these neutrinos fast in the speed of light and the time difference was just 69 a second, so they were arriving 69 seconds earlier than light would arrive quiet.

  • Rightly, the experimentalists have been re analyzing everything they can because it's such a radical result.

  • If it's true on going through everything on, but it looks like they found a couple of sources of error that may account for this difference.

  • Yes, it's to do with actually one of them's to do with the cabling that takes them from the GPS system that they're using to their own to their own optical system.

  • It's an optical cable, Andi.

  • It sounds like it wasn't quite connected well enough on when they tightened up the connection.

  • The time delay that was that they west recording a 69 a second seems to have gone away completely.

  • I'm not an experimentalist, so I have not want to criticize.

  • I'm not going to criticize him because I've had loads of occasions when I've got loose wires and I can't get things to transmit.

  • Well, I think I think that they have done things the right way.

  • I think they will get criticism for this.

  • Pretend I'm still not proven that this is gonna actually screw up the result because there's two effects that they've noticed.

  • One could actually, of course, the neutrinos to go even quicker where you know this one is saying that actually, they might go.

  • There's two effects going on.

  • They're competing one another.

  • This isn't the only possible source of error.

  • They they have another they talked about which I don't really understand, which is also to do with this timing.

  • That's again to do with coordination between the GPS system that they're using to calibrate on Dhe, their own timing mechanism.

  • And they had this other source which, intriguingly, they say that these two sources of era one the connection and one this other source, which I don't understand as they're working in opposite directions, that so you know, they could cancel each other out if they cancel each other out than the results still there.

  • But At the moment, the feeling is probably that they want on that result may disappear.

  • They were sitting on this for three years.

  • They didn't know what the you know.

  • If there was anything wrong, you know, they'd look that it looked at it, looked at I sort of like in it to Darwin.

  • Actually, when Darwin came up with the origin of the species, his religious convictions meant that he was very nervous about announcing it to the scientific community, and he sat on it for years.

  • It's a bit like that in a way, you could they realize the controversy of what they were going to announce, and so they sat on it and I wouldn't want to sit on it forever.

  • The right thing to do is to open her up to the rest of the scientific community, and they can study it and they can see if they can find a fault.

  • I think that's the right thing to do.

  • When we stand here and look at those mountains, it really hits home to me.

  • How amazing it is that neutrinos pass through mountains.

  • What happens when Fred the neutrino is passing through that many atoms that much rock.

  • How come nothing's hitting anything?

  • The Fred the neutrino is you think?

  • I think it's no.

  • A bad analogy is you basically would replace that rock.

  • As far as Fred is concerned with nothing more than a veil of funk O R.

  • It's on your passing through and you just you just bypass it, but you don't you don't see it, but you just would go straight through it.

  • You're going.

  • You don't interact with it in any real way, and it's only very occasionally will.

  • Will Fred actually feel the impact off one of the atoms?

  • That's and in fact it better.

  • Lee passes all the way through the rock, and the thing that the ends up detecting it is an even more concentrated regime of the detectives.

  • They use a really solid detectors of lead, which has got high density of atoms in there.

  • And basically you've just got to increase the density of atoms as much as you can so that the nuclear of the atom, the you maximize the chances that this new Treanor, which has got no into no riel interaction cross section, which means the area that it's going to hit with anything else that's so small that it just passes all the way through.

  • It's a point like object.

  • Remember, fundamental object is the neutrino it just shoots through.

  • And you've got to be very lucky that it actually hits one on.

  • Believes a re Kyle that you can detect so you maximize the density of the material.

  • It's passing through the gaps, but also it's not experience.

  • It has got no charge.

  • A neutrino has got no electric charge, so it's not feeling the effects of the protons.

  • It's not feeling the effects of the electrons, at least in terms of the electromagnetic interaction, which is far stronger.

  • So the protons and neutrons are highly.

  • They're all then the producing electro static interactions.

  • But the neutrino doesn't feel them.

  • It's not feel it doesn't feel the strong interaction.

  • So this high density of protons and neutrons, which have got the quarks in there the neutrino, doesn't feel those strong interactions.

  • The only thing it is beginning to feel are the weak interactions.

  • That's the only thing it feels, and they're much weaker than than any of the others.

  • So basically it just goes through, feels everything is again personally If it isn't proved to be a real effect, I will be gutted.

  • The fieriest are we actually got it.

  • You know, this is so exciting when it looked like it might be a credible result, you know me.

  • Is that the result?

  • You know, I'm sort of working in this field at a time when it is hugely dramatic results is occurred, and, you know, that really excited me.

  • And, you know, the game was on to try and find ways to explain it.

  • I'd already thought of a project for one of my PhD students.

  • Potentially, you know, tried explain.

  • This result 41 bothered now.

  • So something like a nucleus has various weapons in its arsenal to affect other other particles, and a lot of its weapons or one of its big weapons is neutralized.

  • In the case of a new dreams, that's it's electric, It's electrostatic.

  • Forces have neutralized and it's strong.

  • Forces are neutralized.

  • The two big weapons it's got gone and it's just left gravity.

  • Is it irrelevant is so weak on these scales.

  • It's just left with the Elect with the weak interaction with being weak means it's very difficult to detect them Yeah, I always noticed all these things.

  • I like interesting results like this.

  • You know, you don't do science for the just to sort of do the boring old.

  • I don't do science to do that.

  • Just boring old stuff, you know?

  • I want it.

  • I want to do interesting stuff.

  • I wanted to exciting stuff, you know, stuff that is really sort of moving on from what we previously thought.

  • That's what excites me, is a scientist.

  • And it may be, you know, I would like the sort of an ominous results to come out when I was doing my PhD.

  • And that's what it was announced, that the acceleration of the universe, which was last year's Nobel Prize, was given for.

  • And you know, I remember the time you were very skeptical about that.

  • And if you say, oh, it'll just be some systematics whatever.

  • But actually that's turned out to sort of stood the test of time.

  • It seems this one might not.

  • But at the time that was a huge is honest dominated my career since that that acceleration of the universe result.

  • So, you know, this is what it does.

  • The's a great things way should embrace these things.

  • Obviously, we need to be scientifically responsible and, you know, not just jump on a bandwagon, because it's sounds good.

  • But, you know, these are exciting things.

  • And I just said I'll be gutted.

  • Thanks.

  • Right.

  • How often do you see that?

  • Wow.

Yeah, if we just look over here down in the valley, there is where, sir Nous on da the S P s collider provides the initial protons and from those initial protons, they then lead to the generation of the neutrinos on those neutrinos.

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B1 中級

比光還慢的中微子 - 六十個符號 (Neutrinos slower than light - Sixty Symbols)

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    林宜悉 發佈於 2021 年 01 月 14 日
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