How simple ideas lead to scientific discoveries

Kako preproste ideje vodijo do znanstvenih odkritij

Translator: Jenny Zurawell

Translator: Blaž Koritnik Reviewer: Lenka Tušar

(Glasba)

Ena od zanimivih stvari o možganih je ta, da

One of the funny things about owning a brain

is that you have no control over the things

nimamo nadzora nad tem, kar možgani sprejemajo in obdržijo;

that it gathers and holds onto, the facts and the stories.

to so zgodbe in dejstva. Ko se staramo, postane še hujše.

And as you get older, it only gets worse.

Stvari včasih ždijo leta in leta,

Things stick around for years sometimes

before you understand why you're interested in them,

preden razumemo, zakaj nas zanimajo

in kaj nam prinaša njihov vnos.

before you understand their import to you.

Podal vam bom tri zgodbe.

Here's three of mine.

When Richard Feynman was a young boy in Queens,

Ko je bil Richard Feynman še fantek, živeč v Queensu

he went for a walk with his dad and his wagon and a ball.

je bil na sprehodu s svojim očetom, s sabo pa je imel še voziček in žogo.

Opazil je, da ko je vlekel voziček za seboj,

He noticed that when he pulled the wagon, the ball went to the back of the wagon.

se je žoga zakotalila proti koncu vozička.

Očeta je vprašal: "Zakaj se je žoga premaknila proti koncu?"

He asked his dad, "Why does the ball go to the back of the wagon?"

Oče pa mu je odvrnil: "Temu se reče vztrajnost."

And his dad said, "That's inertia."

Richard je vprašal: "Kaj pa je to?" Oče mu je odgovoril:

He said, "What's inertia?" And his dad said, "Ah.

"Vztrajnost je ime, ki so ga dali znastveniki

Inertia is the name that scientists give

to the phenomenon of the ball going to the back of the wagon."

pojavu, ko se žoga zakotali proti koncu vozička.

(Laughter)

V resnici pa noben ne ve, kaj je to."

"But in truth, nobody really knows."

Feynman je diplomiral

Feynman went on to earn degrees

na MIT-u, Princetonu, razložil je nesrečo raketoplana Challenger,

at MIT, Princeton, he solved the Challenger disaster,

dobil je Nobelovo nagrado za fiziko

he ended up winning the Nobel Prize in Physics

za lastne Feynmanove diagrame, ki so opisovali premikanje osnovnih delcev.

for his Feynman diagrams, describing the movement of subatomic particles.

Zasluge pripisuje temu pogovoru z očetom.

And he credits that conversation with his father as giving him a sense

Dal mu je občutek,

that the simplest questions could carry you out to the edge of human knowledge,

da nas lahko preprosta vprašanja popeljejo na kraj človeškega védenja

in tam se je hotel malce poigrati.

and that that's where he wanted to play.

In se je.

And play he did.

Eratosthenes was the third librarian at the great Library of Alexandria,

Eratosten je bil tretji knjižničar v veliki knjižnici v Aleksandriji

and he made many contributions to science.

in je veliko pripomogel k znanosti.

Zgodba o dosežku, po katerem je najbolj znan

But the one he is most remembered for

began in a letter that he received as the librarian,

se je začela s pismom, ki ga je prejel kot knjižničar,

from the town of Swenet, which was south of Alexandria.

iz mesta Swenet, južno od Aleksandrije.

V pismu je bilo navedeno dejstvo o katerem je premišljeval Eratosten.

The letter included this fact that stuck in Eratosthenes' mind,

Pošiljatelj je zapisal, da ko je opoldne na sončev solsticij

and the fact was that the writer said,

at noon on the solstice, when he looked down this deep well,

pogledal v globok vodnjak,

he could see his reflection at the bottom,

je lahko videl svoj odsev na dnu in da je njegova glava

and he could also see that his head was blocking the sun.

delala senco.

I should tell you -- the idea that Christopher Columbus

Naj vam kar zdaj povem. Ideja, da je Krištof Kolumb odkril, da je svet okrogel

discovered that the world is spherical is total bull.

je neumnost. To sploh ni res.

It's not true at all.

Pravzaprav, že od časa Aristotla je vsak izobraženec

In fact, everyone who was educated understood that the world was spherical

s preprostim opazovanjem razumel, in to je Aristotel tudi dokazal,

since Aristotle's time.

Aristotle had proved it with a simple observation.

da je svet okrogel.

Opazili so, da vsakič, ko se je videla Zemljina senca na površju Lune

He noticed that every time you saw the Earth's shadow on the Moon,

je bila senca okrogla.

it was circular,

Edina oblika, ki meče tako senco

and the only shape that constantly creates a circular shadow

je krogla, kar dokazuje, da je Zemlja okrogla.

is a sphere, Q.E.D. the Earth is round.

Nihče pa ni vedel, kako velika je,

But nobody knew how big it was

until Eratosthenes got this letter with this fact.

dokler ni Eratosten dobil tistega pisma.

Razumel je, da je sonce direktno nad mestom Swenet,

So he understood that the sun was directly above the city of Swenet,

because looking down a well, it was a straight line

kajti če gledaš v vodnjak, je bilo tako kot da bi ravna črta,

all the way down the well, right past the guy's head up to the sun.

potekala mimo glave v vodnjak.

Eratosten je vedel še nekaj.

Eratosthenes knew another fact.

He knew that a stick stuck in the ground in Alexandria

Palica je, zapičena v tla v Aleksandriji

at the same time and the same day, at noon,

ob istem dnevu, ob istem času, opoldne,

the sun's zenith, on the solstice,

ko je sonce v zenitu, ob solsticiju

the sun cast a shadow that showed that it was 7.2 degrees off-axis.

metala senco pod kotom 7,2 stopinji.

Če poznate obseg kroga

If you know the circumference of a circle, and you have two points on it,

in imate dve točki na njem,

all you need to know is the distance between those two points,

potem morate samo vedeti razdaljo med tistima točkama,

and you can extrapolate the circumference.

da ekstrapolirate obseg.

360 degrees divided by 7.2 equals 50.

360 stopinj, deljeno z 7,2 je enako 50.

Vem, da je okrogla številka in celo jaz sem sumničav do te zgodbe

I know it's a little bit of a round number,

and it makes me suspicious of this story too,

ampak je dobra, zato bom nadaljeval.

but it's a good story, so we'll continue with it.

Erastoten je rabil vedeti, koliko je razdalja med Swenetom in Aleksandrijo.

He needed to know the distance between Swenet and Alexandria,

To je dobro, kajti geografija mu je šla od rok.

which is good because Eratosthenes was good at geography.

Pravzaprav je ustvaril besedo "geografija".

In fact, he invented the word geography.

(Laughter)

Pot med Swenetom in Aleksandrijo

The road between Swenet and Alexandria was a road of commerce,

je bila trgovska pot

and commerce needed to know how long it took to get there.

in trgovci so morali vedeti, koliko časa je trajala pot.

It needed to know the exact distance, so he knew very precisely

Morali so vedeti natančno razdaljo in on je točno vedel,

that the distance between the two cities was 500 miles.

da je razdalja med mestoma 500 milj (približno 805 km).

Multiply that times 50, you get 25,000,

Pomnožite s 50 in dobite 25.000 milj (40.233 km),

which is within one percent of the actual diameter of the Earth.

kar odstopa za približno 1 odstotek od dejanskega premera Zemlje.

To je izračunal 2.200 let nazaj.

He did this 2,200 years ago.

Živimo v dobi,

Now, we live in an age where

multi-billion-dollar pieces of machinery are looking for the Higgs boson.

ko oprema, vredna več milijard dolarjev išče Higgsov bozon.

We're discovering particles

Odkrivamo delce, ki lahko potujejo hitreje od svetlobe

that may travel faster than the speed of light,

in takšna odkritja so možna

and all of these discoveries are made possible

s tehnologijo, ki so jo razvili v zadnjih desetletjih.

by technology that's been developed in the last few decades.

But for most of human history,

Toda večino časa v naši zgodovini

smo morali odkriti take stvari z očmi, ušesi in umom.

we had to discover these things using our eyes and our ears and our minds.

Armand Fizeau je bil eksperimentalni fizik v Parizu.

Armand Fizeau was an experimental physicist in Paris.

His specialty was actually refining and confirming other people's results,

Njegova posebnost je bila, da je dodeloval in potrjeval rezultate drugih ljudi

in morda zveni kot pobiranje zaslug

and this might sound like a bit of an also-ran,

but in fact, this is the soul of science,

toda to je pravzaprav bistvo znanosti,

because there is no such thing as a fact that cannot be independently corroborated.

ker nobeden ne more kar sam potrditi nekega dejstva.

Poznal je Galilejeve poskuse,

And he was familiar with Galileo's experiments

ko je skušal določiti svetlobi njeno hitrost.

in trying to determine whether or not light had a speed.

Galileo je izvedel čudovit poskus.

Galileo had worked out this really wonderful experiment

where he and his assistant had a lamp, each one of them was holding a lamp.

On in njegov pomočnik sta imela vsak svojo svetilko.

Galileo je posvetil s svojo, isto je storil tudi pomočnik.

Galileo would open his lamp, and his assistant would open his.

Bila sta res dobro usklajena.

They got the timing down really good.

They just knew their timing.

Preprosto sta to vedela. Potem sta stala na dveh hribih,

And then they stood at two hilltops,

two miles distant, and they did the same thing,

približno 3,2 km narazen in ponovila poskus. Galileo je domneval,

on the assumption from Galileo that if light had a discernible speed,

da če ima svetloba razpoznavno hitrost,

he'd notice a delay in the light coming back from his assistant's lamp.

bi opazil zakasnitev, ko bi pomočnik posvetil s svojo svetilko.

But light was too fast for Galileo.

Ampak svetloba je bila prehitra za Galileja.

Za kar nekajkrat je napačno domneval,

He was off by several orders of magnitude when he assumed

that light was roughly ten times as fast as the speed of sound.

da je svetloba približno desetkrat hitrejša od zvoka.

Fizeau was aware of this experiment.

Fizeau je poznal ta poskus. Živel je v Parizu

He lived in Paris, and he set up two experimental stations,

in je postavil dve eksperimentalni postaji,

oddaljeni med seboj približno 8,6 km.

roughly 5.5 miles distant, in Paris.

Rešil je Galilejevo zagato tako, da

And he solved this problem of Galileo's,

and he did it with a really relatively trivial piece of equipment.

je uporabil relativno vsakdanjo opremo.

Uporabil je eno od teh.

He did it with one of these.

Za nekaj časa bom pospravil daljinec,

I'm going to put away the clicker for a second

because I want to engage your brains in this.

ker hočem, da malce razmišljate zraven.

So this is a toothed wheel.

Tole je zobato kolesce. Ima zareze

It's got a bunch of notches and it's got a bunch of teeth.

in zobce.

This was Fizeau's solution to sending discrete pulses of light.

Tako je Fizeau lahko pošiljal ločene curke svetlobe.

He put a beam behind one of these notches.

Za eno od teh zarez je posvetil z žarkom.

If I point a beam through this notch at a mirror,

Če posvetimo s takim žarkom v ogledalo

oddaljeno 8 km stran, se žarek odbija od ogledala

five miles away, that beam is bouncing off the mirror

and coming back to me through this notch.

in vrača skozi zarezo.

Ko pa je kolesce zavrtel hitreje, se je zgodilo nekaj zanimivega.

But something interesting happens as he spins the wheel faster.

Zdelo se mu je, kot da bi se žarku svetlobe, ki se vrača v njegovo oko

He notices that it seems like a door is starting to close

on the light beam that's coming back to his eye.

zapirala vrata.

Why is that?

Čemu je tako?

Vzrok je v curku svetlobe, ki se ni vračal

It's because the pulse of light is not coming back

through the same notch.

nazaj skozi isto zarezo. Pravzaprav je zadeval v zobec.

It's actually hitting a tooth.

And he spins the wheel fast enough and he fully occludes the light.

Dovolj hitro je vrtel kolesce

in prekril svetlobo.

And then, based on the distance between the two stations

Potem pa je sodeč po razdalji med postajama,

and the speed of his wheel and the number of notches in the wheel,

hitrosti kolesca in številom zarez

he calculates the speed of light to within two percent of its actual value.

izračunal hitrost svetlobe, ki je odstopala za približno 2 odstotka od dejanske količine.

To je storil leta 1849.

And he does this in 1849.

To me res privlači pri znanosti.

This is what really gets me going about science.

Whenever I'm having trouble understanding a concept,

Ko imam težave z razumevanjem neke zamisli, grem raziskovat, kako so ljudje to odkrili.

I go back and I research the people that discovered that concept.

Pogledam njihovo pot spoznanja.

I look at the story of how they came to understand it.

What happens when you look

Ko pogledate, o čem so razmišljali izumitelji

at what the discoverers were thinking about

when they made their discoveries,

ob svojih odkritjih boste razumeli,

is you understand that they are not so different from us.

da niso tako različni od nas.

Vsi smo vreče mesa in vode. Začnemo z istimi pripomočki.

We are all bags of meat and water. We all start with the same tools.

Všeč mi je to, da se različne veje znanosti imenujejo študijska področja.

I love the idea that different branches of science are called fields of study.

Večina ljudi meni, da je znanost zaprta, črna škatla,

Most people think of science as a closed, black box,

when in fact it is an open field.

ampak v bistvu je odprto področje.

And we are all explorers.

Vsi smo raziskovalci.

Osebe, o katerih odkritjih sem govoril so le malce bolj pomislile,

The people that made these discoveries just thought a little bit harder

about what they were looking at, and they were a little bit more curious.

kaj v bistvu gledajo, bile so malo bolj radovedne.

And their curiosity changed the way people thought about the world,

Njihova radovednost je spremenila način, kako ljudje razmišljajo o svetu

and thus it changed the world.

in tako je tudi prišlo do sprememb v svetu.

They changed the world, and so can you.

Spremenili so svet in lahko ga tudi vi.

Hvala.

Thank you.

(Applause)

(Aplavz)