Henry Lin: What we can learn from galaxies far, far away

Translator: Mirna Lukovic Reviewer: Samra Cebiric

Here are some images of clusters of galaxies.

Evo nekoliko slika skupina galaksija.

They're exactly what they sound like.

I one su upravo to.

They are these huge collections of galaxies,

One su ogromni zbirovi galaksija,

bound together by their mutual gravity.

povezani zajedničkom gravitacijom.

So most of the points that you see on the screen

Većina tačaka koje vidite na ekranu

are not individual stars,

nisu pojedinačne zvijezde,

but collections of stars, or galaxies.

već zbirovi zvijezda ili galaksija.

Now, by showing you some of these images,

Pokazujući vam neke od ovih slika,

I hope that you will quickly see that

nadam se da ćete brzo uvidjeti da su

galaxy clusters are these beautiful objects,

zbirovi galaksija ovi prelijepi objekti,

but more than that,

ali i više od toga.

I think galaxy clusters are mysterious,

Lično mislim da su skupine sazviježđa misteriozne,

they are surprising,

da su iznenađujuće

and they're useful.

i da su korisne.

Useful as the universe's most massive laboratories.

Korisne kao najveće laboratorije univerzuma.

And as laboratories, to describe galaxy clusters

I kao kada opisujete laboratorije, opisati skupine galaksija

is to describe the experiments

znači opisati eksperimente

that you can do with them.

koje s njima možete raditi.

And I think there are four major types,

A ja mislim da postoje četiri glavne vrste eksperimenata,

and the first type that I want to describe

a prva vrsta koju želim da opišem

is probing the very big.

je ispitivanje jako velikog.

So, how big?

Koliko velikog?

Well, here is an image of a particular galaxy cluster.

Evo slike određene skupine galaksija.

It is so massive that the light passing through it

Ova je skupina toliko velika da se svjetlo koje kroz nju prolazi

is being bent, it's being distorted

savija, deformira

by the extreme gravity of this cluster.

zbog ekstremne gravitacije ovog zbira sazviježđa.

And, in fact, if you look very carefully

I, zapravo, ako dobro pogledate

you'll be able to see rings around this cluster.

vidjet ćete prstenove oko ove skupine.

Now, to give you a number,

Da biste dobili predstavu,

this particular galaxy cluster

ova konkretna skupina galaksija

has a mass of over one million billion suns.

ima masu veću od jednog miliona milijardi sunaca.

It's just mind-boggling how massive these systems can get.

Jednostavno je nepojmljivo koliko mogu biti veliki ovi sistemi.

But more than their mass,

Ali, važnija od njihove mase

they have this additional feature.

je njihova dodatna osobina.

They are essentially isolated systems,

One su u osnovi izolovani sistemi,

so if we like, we can think of them

tako da, ako želimo, o njima možemo razmišljati

as a scaled-down version of the entire universe.

kao o umanjenim verzijama cijelog svemira.

And many of the questions that we might have

Mnoga pitanja koja možda imamo

about the universe at large scales,

o svemiru, u širem smislu,

such as, how does gravity work?

kao na primjer "kako djeluje gravitacija?"

might be answered by studying these systems.

mogu biti odgovorena proučavanjem ovih sistema.

So that was very big.

To je, dakle, jako veliko.

The second things is very hot.

Druga stvar je - vrelo.

Okay, if I take an image of a galaxy cluster,

Ako uzmem sliku skupine galaksija

and I subtract away all of the starlight,

i s nje uklonim svjetlost zvijezda

what I'm left with is this big, blue blob.

ostaje mi ova velika, plava mrlja.

This is in false color.

Ovo nije prava boja.

It's actually X-ray light that we're seeing.

Ovo što vidimo je zapravo svjetlo rendgenskog zraka.

And the question is, if it's not galaxies,

Sada je pitanje, ako to nisu galaksije,

what is emitting this light?

šta onda emituje ovu svjetlost?

The answer is hot gas,

Odgovor je vreli gas,

million-degree gas --

gas od milion stepeni -

in fact, it's plasma.

zapravo, to je plazma.

And the reason why it's so hot

A razlog zašto je tako vrelo

goes back to the previous slide.

je na prethodnom slajdu.

The extreme gravity of these systems

Ekstremna gravitacija ovih sistema

is accelerating particles of gas to great speeds,

ubrzava čestice gasa do velikih brzina,

and great speeds means great temperatures.

a velike brzine znače i velike temperature.

So this is the main idea,

Ovo je, dakle, osnovna ideja,

but science is a rough draft.

ali nauka je grubi nacrt.

There are many basic properties about this plasma

Mnoge osnovne osobine plazme

that still confuse us,

nas još uvijek zbunjuju,

still puzzle us,

tjeraju na razmišljanje

and still push our understanding

i pomijeraju granice našeg razumijevanja

of the physics of the very hot.

fizike vrelog.

Third thing: probing the very small.

Treća stvar: ispitivanje jako malog.

Now, to explain this, I need to tell you

Da bih vam ovo objasnio, moram vam reći

a very disturbing fact.

vrlo uznemirujuću činjenicu.

Most of the universe's matter

Najveći dio materije svemira

is not made up of atoms.

nije sačinjen od atoma.

You were lied to.

Lagali su vam.

Most of it is made up of something very, very mysterious,

Najveći dio je sačinjen od nečeg jako, jako misterioznog,

which we call dark matter.

što se zove tamna materija.

Dark matter is something that doesn't like to interact very much,

Tamna materija je nešto što ne voli interakciju,

except through gravity,

osim kroz gravitaciju,

and of course we would like to learn more about it.

i, naravno, želimo znati više o njoj.

If you're a particle physicist,

Ako se bavite fizikom čestica,

you want to know what happens when we smash things together.

želite znati šta se dešava kada sudarimo dvije stvari.

And dark matter is no exception.

A tamna materija nije izuzetak.

Well, how do we do this?

I kako onda to radimo?

To answer that question,

Da bih odgovorio na to pitanje

I'm going to have to ask another one,

moram postaviti drugo,

which is, what happens when galaxy clusters collide?

a to je "šta se dešava kada se sudare dvije skupine galaksija?"

Here is an image.

Evo slike.

Since galaxy clusters are representative

Skupine galaksija predstavljaju

slices of the universe, scaled-down versions.

isječke univerzuma, njegove umanjene verzije.

They are mostly made up of dark matter,

Sačinjene su uglavnom od tamne materije,

and that's what you see in this bluish purple.

i to je ono što vidite u plavo-ljubičastoj boji.

The red represents the hot gas,

Crvena predstavlja vreli gas,

and, of course, you can see many galaxies.

i naravno, vidite mnogo galaksija.

What's happened is a particle accelerator

Ono što se desilo je ubrzivač čestica

at a huge, huge scale.

na ogromnom, ogromnom nivou.

And this is very important,

Ovo je jako važno

because what it means is that very, very small

jer znači da bi se jako, jako mali

effects that might be difficult to detect in the lab,

efekti koje bi bilo teško detektovati u laboratoriji

might be compounded and compounded

mogli jediniti i jediniti

into something that we could possibly observe in nature.

u nešto što bismo mogli primijetiti u prirodi.

So, it's very funny.

Smiješno je.

The reason why galaxy clusters

Razlog zašto preko skupine galaksija

can teach us about dark matter,

možemo učiti o tamnoj materiji,

the reason why galaxy clusters

razlog zašto kroz skupine galaksija

can teach us about the physics of the very small,

možemo učiti o fizici jako malog,

is precisely because they are so very big.

je upravo zato što su tako velike.

Fourth thing: the physics of the very strange.

Četvrta stvar: fizika jako neobičnog.

Certainly what I've said so far is crazy.

Naravno da je sve što sam do sada rekao ludo.

Okay, if there's anything stranger

Uredu, ako postoji išta neobičnije

I think it has to be dark energy.

mislim da to onda mora biti tamna energija.

If I throw a ball into the air,

Ako bacim loptu u zrak,

I expect it to go up.

očekujem da će ići gore.

What I don't expect is that it go up

Ono što ne očekujem je da ide gore

at an ever-increasing rate.

sve brže i brže.

Similarly, cosmologists understand why

Slično tome, kozmolozi razumiju zašto

the universe is expanding.

se svemir širi.

They don't understand why it's expanding

Ne razumiju zašto se širi

at an ever-increasing rate.

sve brže i brže.

They give the cause of this

Razlog ovog

accelerated expansion a name,

ubrzanog širenja ima ime,

and they call it dark energy.

i zovu ga tamna energija.

And, again, we want to learn more about it.

I opet želimo znati više o njoj.

So, one particular question that we have is,

Jedno određeno pitanje koje imamo je

how does dark energy affect the universe

kako tamna energija utječe na svemir

at the largest scales?

na većem planu?

Depending on how strong it is,

Zavisno od toga koliko je jaka,

maybe structure forms faster or slower.

možda se strukture formiraju brže ili sporije.

Well, the problem with the large-scale structure

Problem sa velikom strukturom

of the universe is that it's horribly complicated.

svemira je taj što je užasno komplikovana.

Here is a computer simulation.

Pogledajte kompjutersku simulaciju.

And we need a way to simplify it.

Potreban nam je način da je pojednostavimo.

Well, I like to think about this using an analogy.

O ovome volim razmišljati koristeći analogiju.

If I want to understand the sinking of the Titanic,

Ako želim razumjeti kako je potonuo Titanik

the most important thing to do

nije najvažnije

is not to model the little positions

tačno postaviti svaki djelić

of every single little piece of the boat that broke off.

koji se odvojio s broda.

The most important thing to do is

Najvažnije je

to track the two biggest parts.

pronaći dva najveća dijela.

Similarly, I can learn a lot about the universe

Na sličan način mogu mnogo naučiti o svemiru

at the largest scales

na širem planu

by tracking its biggest pieces

prateći njegove najveće dijelove,

and those biggest pieces are clusters of galaxies.

a najveći dijelovi su skupine galaksija.

So, as I come to a close,

Kako se bližim završetku

you might feel slightly cheated.

možda se osjećate malo prevarenima.

I mean, I began by talking about

Mislim, počeo sam govorom o tome

how galaxy clusters are useful,

kako su skupine galaksija korisne

and I've given some reasons,

i naveo sam neke razloge,

but what is their use really?

ali koja je njihova stvarna korist?

Well, to answer this,

Da bih odgovorio na ovo,

I want to give you a quote by Henry Ford

želim citirati Henrya Forda

when he was asked about cars.

kada su ga pitali o autima.

He had this to say:

On je rekao ovo:

"If I had asked people what they wanted,

"Da sam pitao ljude šta žele,

they would have said faster horses."

tražili bi brže konje".

Today, we as a society are faced

Danas smo kao društvo suočeni

with many, many difficult problems.

sa jako mnogo teških problema.

And the solutions to these problems are not obvious.

A rješenja ovih problema nisu očigledna.

They are not faster horses.

Ona nisu "brži konji".

They will require an enormous amount of

Ta će rješenja zahtijevati ogromnu količinu

scientific ingenuity.

naučne genijalnosti.

So, yes, we need to focus,

Dakle, da, moramo se fokusirati,

yes, we need to concentrate,

da, moramo se koncentrisati,

but we also need to remember that

Ali isto tako moramo upamtiti da

innovation, ingenuity, inspiration --

inovacija, genijalnost, inspiracija -

these things come

ove stvari dolaze

when we broaden our field of vision

kada proširimo svoje vidike,

when we step back

kada zakoračimo unazad,

when we zoom out.

kada sagledamo veću sliku.

And I can't think of a better way to do this than

A ja ne mogu da zamislim bolji način da se ovo uradi

by studying the universe around us. Thanks.

nego posmatranjem svemira oko nas. Hvala.

(Applause)

Aplauz