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Học tiếng Anh cùng Ted talks, Eric Haseltine: Đột phá khoa học lớn tiếp đến sẽ là gì?

September 9, 2016

 Ted talk là một diễn đàn mở nhằm chia sẻ các ý tưởng tuyệt vời từ những diễn giả xuất chúng, hãy lắng nghe để mở mang kiến thức lẫn ngôn ngữ.

 

Xem lời thoại bên dưới nếu bạn cần

 

0:12

Tonight, I'm going to share with you my passion for science.

0:16

I'm not talking about science that takes baby steps.

0:19

I'm talking about science that takes enormous leaps.

0:23

I'm talking Darwin, I'm talking Einstein,

0:27

I'm talking revolutionary science that turns the world on its head.

0:31

In a moment, I'm going to talk about two ideas that might do this.

0:35

I say "might"

0:37

because, with revolutionary ideas, most are flat wrong,

0:39

and even those that are right seldom have the impact

0:42

that we want them to have.

0:44

To explain why I picked two ideas in particular,

0:46

I'm going to start with a mystery.

0:48

1847, Vienna, Austria.

0:53

Ignaz Semmelweis was a somber, compulsively thorough doctor

0:56

who ran two maternity clinics.

0:58

They were identical except for one thing.

1:01

Women were dying of high fevers soon after giving birth

1:04

three times more often at one of the clinics than at the other.

1:08

Trying to figure out what the difference was that caused this,

1:11

Semmelweis looked at everything he could.

1:13

Sanitation? No.

1:15

Medical procedures? No.

1:18

Air flow? No.

1:20

The puzzle went unsolved until he happened to autopsy a doctor

1:24

who died of an infected scalpel cut.

1:26

The doctor's symptoms were identical to those of the mothers who were dying.

1:30

How was that possible?

1:31

How could a male doctor get the same thing as new mothers?

1:35

Semmelweis reconstructed everything the doctor had done

1:38

right before he got sick,

1:40

and he discovered that he'd been autopsying a corpse.

1:44

Had something gotten in his wound that killed him?

1:48

With growing excitement,

1:50

Semmelweis looked for any connection he could

1:53

between dead bodies in the morgue and dead mothers in his delivery room,

1:58

and he found it.

2:01

It turned out that at the hospital with the high death rate,

2:04

but not the others,

2:06

doctors delivered babies immediately after autopsying corpses in the morgue.

2:11

Aha! Corpses were contaminating the doctors' hands

2:15

and killing his mothers.

2:17

So he ordered the doctors to sterilize their hands,

2:20

and the deaths stopped.

2:23

Dr. Ignaz Semmelweis had discovered infectious disease.

2:28

But the doctors of the day thought he was crazy,

2:31

because they knew, and had for hundreds of years,

2:35

that odorous vapors called miasmas caused disease,

2:40

not these hypothetical particles that you couldn't see.

2:44

It took 20 years for Frenchman Louis Pasteur

2:49

to prove that Semmelweis was right.

2:51

Pasteur was an agricultural chemist

2:54

who tried to figure out why milk and beer spoiled so often.

2:58

He found that bacteria were the culprits.

3:02

He also found that bacteria could kill people in exactly the same way

3:06

that Semmelweis's patients were dying.

3:09

We now look at what I want to talk about tonight, in two ideas.

3:14

We saw it with Semmelweis, that he was a revolutionary.

3:18

He did it for two reasons.

3:19

One, he opened our eyes to a completely new world.

3:23

We'd known since the 1680s about bacteria.

3:26

We just didn't know that bacteria killed people.

3:29

And he also demolished fond ideas that people kept close to their heart.

3:34

Miasmas didn't kill people. Bacteria killed people.

3:38

So this brings me to the two ideas I want to talk about tonight.

3:41

One has opened our eyes to a completely new universe,

3:44

and the other attacks long-held beliefs.

3:48

Let's get started with Dr. Eric Betzig.

3:50

He's a physicist who has opened our eyes to an entirely new world

3:54

by violating the laws of physics.

3:56

Betzig is a true rebel.

3:58

He quit a job at prestigious Bell Laboratory

4:01

inventing new microscopes for biology

4:03

because he thought scientists were taking his brilliant inventions

4:08

and doing lousy work with them.

4:10

So he became a househusband,

4:15

but he never lost his passion for figuring out

4:17

how to get microscopes to see finer and finer details

4:20

than had ever been seen before or ever could be seen.

4:23

This is crucial if we're ever going to understand how cells work,

4:28

and how cancer works,

4:29

and how something 150th the size of a head of a pin

4:35

can do all these amazing things,

4:37

like make proteins

4:39

and move charges around

4:41

and all of those things.

4:43

There's just one problem.

4:46

There's this thing called the law of physics,

4:49

and part of the law of physics is the thing called the diffraction limit.

4:52

The diffraction limit is kind of like when you go to a doctor's office,

4:55

you can only see so far down, no matter how good glasses you have.

4:59

This was a so-called impossible problem.

5:02

But one of Betzig's friends figured out how to take a tiny molecule

5:05

that was smaller than the best microscope could see

5:08

and get it to light up and fluoresce.

5:10

"Aha!" Betzig said.

5:12

"I think maybe the laws of physics are not so unbreakable after all."

5:17

So he lashed together a microscope in his friend's living room.

5:22

He had no laboratory.

5:24

This revolutionary instrument got different protein molecules

5:27

to light up in different colors,

5:30

and with a computer, he was able to turn very, very fuzzy blurs

5:34

into very sharp dots and produce images of unprecedented and startling clarity.

5:41

For this work, last year,

5:43

Eric Betzig won the Nobel Prize.

5:47

Why?

5:48

Because now we can see with unprecedented detail

5:52

things that we never had seen before,

5:54

and now doctors can get a better handle on things like cancer.

5:59

But do you think Betzig was satisfied there?

6:01

No.

6:02

He wanted movies.

6:04

The problem was

6:06

that even the genius microscopes that he invented were just too slow.

6:10

So what did he do?

6:11

He came up with a 200-year-old idea

6:14

called moiré patterns.

6:16

So the way that works is if you take two very, very fine patterns

6:20

and you move them across each other,

6:21

you will see a gross pattern

6:24

that a microscope can see

6:27

that otherwise you would not be able to see.

6:29

So he applied this technique to taking a really blurry image of a cell

6:32

and moving lots of structured light patterns across it

6:35

until this cell became crystal clear.

6:38

And here is the result:

6:40

a mysterious new world,

6:43

full of strange things zipping around

6:45

doing things that we don't know what they're doing.

6:49

But when we figure it out, we'll have a better handle on life itself.

6:53

For example, those green globs that you see?

6:55

Those things are called clathrins.

6:57

They're molecules that protect other molecules

7:00

as they move through a cell.

7:01

Unfortunately, viruses sometimes hijack those to infect cells.

7:06

Also, you see those little squiggly wormlike things moving around?

7:09

Those are actin molecules.

7:11

Unfortunately, viruses also climb down those things

7:14

to get into the cell nucleus

7:15

to replicate themselves and make you sick.

7:18

Now that we can look at movies

7:20

of what's actually going on deep inside a cell,

7:23

we have a much better chance of curing viral diseases like AIDS.

7:27

So when you look at a movie like this,

7:29

it's very clear that Betzig has opened our eyes to a completely new world.

7:34

But he hasn't shattered any cherished beliefs.

7:39

That leads us to Dr. Aubrey de Grey

7:42

at Cambridge.

7:44

De Grey definitely has scientists squirming with an interesting idea:

7:48

we can be immortal.

7:50

We can beat aging.

7:51

Now, most scientists think he's a crackpot.

7:55

Any Biology 101 student knows

7:58

that aging is an inevitable consequence of living.

8:02

For example, when we eat,

8:04

we take in food and we metabolize it,

8:06

and that throws off what we call free radicals.

8:09

You might have heard of those.

8:10

Also known as oxygen ions,

8:12

those bind to our DNA, cause it to mutate,

8:14

and cause us to get old and lose our hair.

8:17

(Laughter)

8:18

It's just like, no, it's exactly like

8:21

oxygen binding to iron and making it rust.

8:23

So you age because you rust out.

8:26

(Laughter)

8:28

Oh, and scientists also know there is something called immortality:

8:33

in cancer cells.

8:35

So if you stop aging,

8:37

all of you are going to turn into giant walking malignant tumors.

8:42

These are cherished beliefs, but could de Grey be on to something?

8:47

I think he deserves a closer look.

8:48

First of all, I have a really hard time seeing him as a crackpot.

8:52

Yeah, he started off life as a computer scientist,

8:54

not a biologist,

8:55

but he earned a PhD in biology from Cambridge,

8:59

and he has published some very significant work

9:02

on mitochondrial DNA and a bunch of other stuff.

9:04

Secondly, he started an antiaging foundation

9:07

that has identified seven different causes of aging,

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to me, that seem very plausible,

9:12

and he is hot in pursuit of fixes for every single one of them.

9:16

For example, one of the reasons we age is that our mitochondrial DNA mutates,

9:21

and we get kind of old and our cells lose energy.

9:25

He believes, and he's made a convincing case,

9:27

that using viruses we can do gene therapy,

9:30

fix that DNA

9:31

and rejuvenate our cells.

9:35

One more thing.

9:36

We have an existent proof

9:38

that extreme longevity is possible.

9:42

Bristlecone pine trees live 5,000 years,

9:47

and some lobsters don't age at all.

9:52

Now, this doesn't mean that de Grey is going to revolutionize our lifespans.

9:57

I mean, after all, we're not trees, and most of us are not lobsters.

10:00

(Laughter)

10:02

But I've got to believe that there are Darwins and Einsteins out there,

10:07

and I'll tell you why.

10:09

Consider this:

10:11

there are seven times more people alive today than during Darwin's time.

10:16

There are four times as many people alive today as Einstein.

10:19

When you consider

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that the proportion of scientists in the population has skyrocketed,

10:24

there are now seven million scientists.

10:26

I've got to believe, and I do believe, that there's one of them out there

10:31

who is working right now in obscurity

10:34

to rock our lives, and I don't know about you,

10:36

but I can't wait to be rocked.