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  • In the late 19th century, scientists were trying to solve a mystery.

  • They found that if they had a vacuum tube like this one

  • and applied a high voltage across it,

  • something strange happened.

  • They called them cathode rays.

  • But the question was: What were they made of?

  • In England, the 19th century physicist, J.J. Thompson,

  • conducted experiments using magnets and electricity, like this.

  • And he came to an incredible revelation.

  • These rays were made of negatively charged particles

  • around 2,000 times lighter than the hydrogen atom,

  • the smallest thing they knew.

  • So Thompson had discovered the first subatomic particle,

  • which we now call electrons.

  • Now, at the time, this seemed to be a completely impractical discovery.

  • I mean, Thompson didn't think there were any applications of electrons.

  • Around his lab in Cambridge, he used to like to propose a toast:

  • "To the electron.

  • May it never be of use to anybody."

  • (Laughter)

  • He was strongly in favor of doing research out of sheer curiosity,

  • to arrive at a deeper understanding of the world.

  • And what he found did cause a revolution in science.

  • But it also caused a second, unexpected revolution in technology.

  • Today, I'd like to make a case for curiosity-driven research,

  • because without it,

  • none of the technologies I'll talk about today

  • would have been possible.

  • Now, what Thompson found here has actually changed our view of reality.

  • I mean, I think I'm standing on a stage,

  • and you think you're sitting in a seat.

  • But that's just the electrons in your body

  • pushing back against the electrons in the seat,

  • opposing the force of gravity.

  • You're not even really touching the seat.

  • You're hovering ever so slightly above it.

  • But in many ways, our modern society was actually built on this discovery.

  • I mean, these tubes were the start of electronics.

  • And then for many years,

  • most of us actually had one of these, if you remember, in your living room,

  • in cathode ray tube televisions.

  • But -- I mean, how impoverished would our lives be

  • if the only invention that had come from here was the television?

  • (Laughter)

  • Thankfully, this tube was just a start,

  • because something else happens when the electrons here

  • hit the piece of metal inside the tube.

  • Let me show you.

  • Pop this one back on.

  • So as the electrons screech to a halt inside the metal,

  • their energy gets thrown out again

  • in a form of high-energy light, which we call X-rays.

  • (Buzzing)

  • (Buzzing)

  • And within 15 years of discovering the electron,

  • these X-rays were being used to make images inside the human body,

  • helping soldiers' lives being saved by surgeons,

  • who could then find pieces of bullets and shrapnel inside their bodies.

  • But there's no way we could have come up with that technology

  • by asking scientists to build better surgical probes.

  • Only research done out of sheer curiosity, with no application in mind,

  • could have given us the discovery of the electron and X-rays.

  • Now, this tube also threw open the gates for our understanding of the universe

  • and the field of particle physics,

  • because it's also the first, very simple particle accelerator.

  • Now, I'm an accelerator physicist, so I design particle accelerators,

  • and I try and understand how beams behave.

  • And my field's a bit unusual,

  • because it crosses between curiosity-driven research

  • and technology with real-world applications.

  • But it's the combination of those two things

  • that gets me really excited about what I do.

  • Now, over the last 100 years,

  • there have been far too many examples for me to list them all.

  • But I want to share with you just a few.

  • In 1928, a physicist named Paul Dirac found something strange in his equations.

  • And he predicted, based purely on mathematical insight,

  • that there ought to be a second kind of matter,

  • the opposite to normal matter,

  • that literally annihilates when it comes in contact:

  • antimatter.

  • I mean, the idea sounded ridiculous.

  • But within four years, they'd found it.

  • And nowadays, we use it every day in hospitals,

  • in positron emission tomography, or PET scans, used for detecting disease.

  • Or, take these X-rays.

  • If you can get these electrons up to a higher energy,

  • so about 1,000 times higher that this tube,

  • the X-rays that those produce

  • can actually deliver enough ionizing radiation to kill human cells.

  • And if you can shape and direct those X-rays where you want them to go,

  • that allows us to do an incredible thing:

  • to treat cancer without drugs or surgery,

  • which we call radiotherapy.

  • In countries like Australia and the UK,

  • around half of all cancer patients are treated using radiotherapy.

  • And so, electron accelerators are actually standard equipment

  • in most hospitals.

  • Or, a little closer to home:

  • if you have a smartphone or a computer --

  • and this is TEDx, so you've got both with you right now, right?

  • Well, inside those devices

  • are chips that are made by implanting single ions into silicon,

  • in a process called ion implantation.

  • And that uses a particle accelerator.

  • Without curiosity-driven research, though,

  • none of these things would exist at all.

  • So, over the years, we really learned to explore inside the atom.

  • And to do that, we had to learn to develop particle accelerators.

  • The first ones we developed let us split the atom.

  • And then we got to higher and higher energies;

  • we created circular accelerators that let us delve into the nucleus

  • and then create new elements, even.

  • And at that point, we were no longer just exploring inside the atom.

  • We'd actually learned how to control these particles.

  • We'd learned how to interact with our world

  • on a scale that's too small for humans to see or touch

  • or even sense that it's there.

  • And then we built larger and larger accelerators,

  • because we were curious about the nature of the universe.

  • As we went deeper and deeper, new particles started popping up.

  • Eventually, we got to huge ring-like machines

  • that take two beams of particles in opposite directions,

  • squeeze them down to less than the width of a hair

  • and smash them together.

  • And then, using Einstein's E=mc2,

  • you can take all of that energy and convert it into new matter,

  • new particles which we rip from the very fabric of the universe.

  • Nowadays, there are about 35,000 accelerators in the world,

  • not including televisions.

  • And inside each one of these incredible machines,

  • there are hundreds and billions of tiny particles,

  • dancing and swirling in systems that are more complex

  • than the formation of galaxies.

  • You guys, I can't even begin to explain how incredible it is

  • that we can do this.

  • (Laughter)

  • (Applause)

  • So I want to encourage you to invest your time and energy

  • in people that do curiosity-driven research.

  • It was Jonathan Swift who once said,

  • "Vision is the art of seeing the invisible."

  • And over a century ago, J.J. Thompson did just that,

  • when he pulled back the veil on the subatomic world.

  • And now we need to invest in curiosity-driven research,

  • because we have so many challenges that we face.

  • And we need patience;

  • we need to give scientists the time, the space and the means

  • to continue their quest,

  • because history tells us

  • that if we can remain curious and open-minded

  • about the outcomes of research,

  • the more world-changing our discoveries will be.

  • Thank you.

  • (Applause)

In the late 19th century, scientists were trying to solve a mystery.

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【TED】Suzie Sheehy: The case for curiosity-driven research (The case for curiosity-driven research | Suzie Sheehy)

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    林宜悉 posted on 2018/11/26
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