How simple ideas lead to scientific discoveries

Kako jednostavne ideje vode do znanstvenih otkrića

Translator: Jenny Zurawell

Prevoditelj: Ivan Stamenković Recezent: Senzos Osijek

(Glazba)

Jedna od čudnih stvari kada posjedujete mozak

One of the funny things about owning a brain

is that you have no control over the things

je da nemate nikakvu kontrolu nad stvarima koje skuplja i zadržava,

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

činjenice i priče. I što postajete stariji, to postaje gore.

And as you get older, it only gets worse.

Stvari ostaju godinama

Things stick around for years sometimes

before you understand why you're interested in them,

dok ne shvatite zašto ste zainteresirani za njih,

prije nego svhatite njihovu važnost za vas.

before you understand their import to you.

Ovdje su tri moje.

Here's three of mine.

When Richard Feynman was a young boy in Queens,

Kada je Richard Feynman bio mladi dječak u Queensu,

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

otišao je u šetnju sa svojim ocem, svojim kolicima

i loptom. I primjetio je da kada vuče kolica,

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

lopta ide prema stražnjem kraju.

I pitao je svog oca, "Zašto lopta ide prema stražnjem kraju kolica?"

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

I njegov otac je rekao, "To je inercija."

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

Rekao je, "Što je inercija?" I njegov otac je rekao: "Ah,

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

inercija je ime koje su znanstvenici dali

Inertia is the name that scientists give

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

fenomenu lopte koja ide prema stražnjem dijelu kolica.

(Laughter)

Ali zapravo, nitko ne zna."

"But in truth, nobody really knows."

Feynman je prikupio diplome

Feynman went on to earn degrees

na MIT-u, Princetonu, riješio je katastrofu Challengera,

at MIT, Princeton, he solved the Challenger disaster,

i na kraju je dobio Nobelovu nagradu iz Fizike

he ended up winning the Nobel Prize in Physics

zbog Feynmanovih dijagrama koji opisuju kretanje subatomskih čestica.

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

I on pripisuje zasluge razgovoru sa svojim ocem

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

jer su mu dali osjećaj

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

da ga najednostavnija pitanja mogu odnijeti do ruba ljudskog znanja,

i da je to mjesto gdje se on želi igrati.

and that that's where he wanted to play.

I igrao se.

And play he did.

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

Eratosten je bio treći knjižničar velike knjižnice u Aleksandriji

and he made many contributions to science.

i dao je mnoge doprinose znanosti.

Ali ono po čemu se najviše pamti

But the one he is most remembered for

began in a letter that he received as the librarian,

započelo je u pismu koje je primio kao knjižničar

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

iz grada Sweneta, koji je bio južno od Aleksandrije.

Pismo je uključivalo činjenicu koja se zaglavila u Eratostenovu umu,

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

i činjenica je bila da je pisac rekao da u podne

and the fact was that the writer said,

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

na solsticiji, kad pogleda u svoj duboki bunar,

he could see his reflection at the bottom,

može vidjeti svoj odraz na dnu, i da također može vidjeti da je njegova glava

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

blokirala sunce.

I should tell you -- the idea that Christopher Columbus

Sad, moram vam reći -- ideja da je Christopher Columbus otkrio da je svijet sferičan

discovered that the world is spherical is total bull.

je potpuno netočna. Uopće nije istina.

It's not true at all.

Zapravo, svatko tko je bi educiran shvaćao je da je svijet sferičan

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

od Aristotelovog vremena, i Aristotel je to dokazao

since Aristotle's time.

Aristotle had proved it with a simple observation.

sa jednostavnom opservacijom.

Primjetio je da svakog puta kada je vidio Zemljinu sjenu na Mjesecu,

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

ona je bila kružna,

it was circular,

i jedini oblik koji uvijek stvara okruglu sjenu

and the only shape that constantly creates a circular shadow

je sfera, dakle Zemlja je okrugla.

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

Ali nitko nije znao kako je velika

But nobody knew how big it was

until Eratosthenes got this letter with this fact.

dok Eratostenes nije dobio pismo s ovom činjenicom.

Tako da je shvaćao da je sunce direktno iznad grada Sweneta,

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

because looking down a well, it was a straight line

jer gledajući niz bunar, to je bila ravna crta

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

dolje niz bunar, ravno pored glave tog tipa do sunca.

Eratostenes je znao još jednu činjenicu.

Eratosthenes knew another fact.

He knew that a stick stuck in the ground in Alexandria

Znao je da štap zabijen u zemlju u Aleksandriji

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

u isto vrijeme i istog dana, u podne,

the sun's zenith, on the solstice,

u sunčev zenit, na solsticij,

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

sunce bi bacalo sjenu koja je pokazivala da je 7,2 stupnja izvan osi.

Sada, ako znate obujam kruga,

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

i imate dvije točke na njemu,

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

sve što trebate je udaljenost između ove dvije točke,

and you can extrapolate the circumference.

kako biste izračunali obujam.

360 degrees divided by 7.2 equals 50.

Tristo šezdeset stupnjeva podijeljeno sa 7,2 jednako je 50.

Znam da je poprilično okrugao broj, i čini i mene sumnjičavim u svezi ove priče,

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

and it makes me suspicious of this story too,

ali to je dobra priča, pa ćemo nastaviti s njom.

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

Trebao je znati udaljenost između Sweneta i Aleksandrije,

He needed to know the distance between Swenet and Alexandria,

što je dobro jer je Eratosten bio dobar u geografiji.

which is good because Eratosthenes was good at geography.

Zapravo, izmislio je riječ geografija.

In fact, he invented the word geography.

(Laughter)

Cesta između Sweneta i Aleksandrije

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

bila je cesta trgovanja,

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

i trgovci su morali znati koliko im dugo treba da tamo dođu,

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

trabali su znati točnu udaljenost, tako da je znao vrlo precizno

that the distance between the two cities was 500 miles.

da je udaljenost između dva grada 500 milja.

Multiply that times 50, you get 25,000,

Pomnožite to sa 50 i dobijete 25000,

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

što je unutar jedan posto stvarnog promjera Zemlje.

Ovo je učinio prije 2200 godina.

He did this 2,200 years ago.

Sad živimo u dobu gdje

Now, we live in an age where

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

multi-milijarderski uređaji traže Higgsov boson.

We're discovering particles

Otkrivamo čestice koje možda putuju brže od brzine svjetlosti,

that may travel faster than the speed of light,

i sva ova otkrića su moguća

and all of these discoveries are made possible

zbog tehnologije koja je razvijena u posljednjih nekoliko desetljeća.

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

But for most of human history,

Ali za većinu ljudske povijesti,

morali smo otkriti te stvari koristeći naše oči i uši i naše umove.

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

Armand Fizeau je eksperimentalni fizičar u Parizu.

Armand Fizeau was an experimental physicist in Paris.

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

Njegova specijalnost je zapravo pročišćavanje i potvrđivanje rezultata drugih,

i ovo će se možda činiti malo kao pirovo istraživanje,

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

but in fact, this is the soul of science,

ali zapravo ovo je duša znanosti,

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

jer nema činjenice koja ne može biti neovisno potkrijepljena.

I on je bio upoznat sa Galileovim eksperimentima

And he was familiar with Galileo's experiments

u kojima je pokušao utvrditi ima li ili ne svjetlo brzinu.

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

Dakle, Galileo je smislio jedan zaista divan eksperiment

Galileo had worked out this really wonderful experiment

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

gdje su on i njegov asistent imali lampu,

i svatko od njih je držao lampu. I Galileo je otvorio svoju lampu, i asistent bi otvorio svoju.

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

I stvarno su dobro svladali tempiranje.

They got the timing down really good.

They just knew their timing.

Znali su tempiranje. I onda su stali na dva vrha brda,

And then they stood at two hilltops,

two miles distant, and they did the same thing,

udaljenih oko dvije milje, i učinili istu stvar pod pretpostavkom

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

Galilea da ako svjetlo ima primjetnu brzinu,

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

on će primjetiti zaostajanje u povratku svjetlosti iz asistentove lampe.

But light was too fast for Galileo.

Ali svjetlost je bila prebrza za Galilea.

Promašio je za nekoliko redova veličine kada je pretpostavio

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 svjetlost otprilike 10 puta brža od brzine zvuka.

Fizeau was aware of this experiment.

Fizeau je bio svjestan ovog eksperimenta. Živio je u Parizu,

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

i postavio je dvije eksperimentalne stanice,

udaljene optilike pet i pol milja

roughly 5.5 miles distant, in Paris.

u Parizu. I riješio je Galileov problem,

And he solved this problem of Galileo's,

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

i učinio je to sa prilično trivijalnim komadom opreme.

Učinio je to s ovime.

He did it with one of these.

Maknut ću kliker na sekundu

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

because I want to engage your brains in this.

jer želim da uključite vaš mozak u ovo.

So this is a toothed wheel.

Ovo je nazubljeni kotač. Ima puno zareza

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

i ima hrpu zubaca.

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

Ovo je bilo Fizeauovo rješenje za slanje diskretnih pulsova svjetlosti.

He put a beam behind one of these notches.

Postavio bi zraku iza jednog od ovih zareza.

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

Ako usmjerim zraku kroz ovaj zarez prema zrcalu,

pet milja udaljenom, zraka se odbija od zrcala

five miles away, that beam is bouncing off the mirror

and coming back to me through this notch.

i dolazi natrag kroz ovaj zarez.

Ali nešto interesantno događa se kako okreće kotač brže.

But something interesting happens as he spins the wheel faster.

Primjećuje da se ponaša kao da se vrata zatvaraju

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

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

iznad zrake koja se vraća njegovom oku.

Why is that?

Zašto je to tako?

Zato što puls svjetlosti ne stiže

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

through the same notch.

natrag kroz isti zarez, već pogađa zubac.

It's actually hitting a tooth.

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

I vrti kotač dovoljno brzo

i u potpunosti zaklanja svjetlost. I onda,

And then, based on the distance between the two stations

na osnovu udaljenosti dvaju stanica

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

i brzine kojom se njegov kotač kreće i broja zareza na kotaču,

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

računa brzinu svjetlosti unutar dva posto njene stvarne vrijednosti.

I to čini 1849.

And he does this in 1849.

To me stvarno pokreće u znanosti.

This is what really gets me going about science.

Whenever I'm having trouble understanding a concept,

Kad god imam problema sa shvaćanjem koncepta, vratim se i istražujem ljude koji su otkrili taj koncept.

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

Gledam priču kako su došli do toga da to shvaćaju.

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

What happens when you look

I ono što se dogodi kada gledate što su oni koji su otkrili razmišljali

at what the discoverers were thinking about

when they made their discoveries,

kada su došli do svojih otkrića, je da shvaćate

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

da nisu tako različiti od nas.

Svi smo mi vreće mesa i vode. I svi počinjemo s istim alatima.

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

Volim ideju da se grane znanosti zovu polja istraživanja.

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

Većina ljudi gleda na znanost kao zatvorenu, crnu kutiju,

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

when in fact it is an open field.

kad je zapravo otvoreno polje.

And we are all explorers.

I mi smo svi istraživači.

Ljudi koji su napravili ova otkrića su samo malo više razmišljali

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.

o tome što su gledali, i bili su malo znatiželjniji.

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

I njihova znatiželja promijenila je način na koji ljudi gledaju svijet,

and thus it changed the world.

i zato je promijenila svijet.

They changed the world, and so can you.

Oni su promijenili svijet, i možete i vi.

Hvala vam.

Thank you.

(Applause)

(Pljesak)