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

Prevodilac: Aniko Kovac Lektor: Mile Živković

Here are some images of clusters of galaxies.

Ovo su neke slike galaktičkih jata.

They're exactly what they sound like.

Ona su upravo ono što im ime kaže.

They are these huge collections of galaxies,

Ogromni skupovi galaksija

bound together by their mutual gravity.

povezani njihovom međusobnom gravitacijom.

So most of the points that you see on the screen

Većina tačaka koje vidite na ekranu

are not individual stars,

nisu pojedinačne zvezde,

but collections of stars, or galaxies.

nego skupovi zvezda ili galaksija.

Now, by showing you some of these images,

Dok gledate neke od ovih slika

I hope that you will quickly see that

nadam se da ćete ubrzo uvideti

galaxy clusters are these beautiful objects,

da su galaktička jata predivni objekti,

but more than that,

ali više od toga,

I think galaxy clusters are mysterious,

smatram da su galaktička jata misteriozna,

they are surprising,

ona su puna iznenađenja

and they're useful.

i ona su korisna.

Useful as the universe's most massive laboratories.

Korisna kao najveće laboratorije univerzuma.

And as laboratories, to describe galaxy clusters

I kao laboratorije, opisati jata galaksija

is to describe the experiments

je opisati eksperimente

that you can do with them.

koje možemo da radimo s njima.

And I think there are four major types,

Smatram da postoje četiri glavna tipa

and the first type that I want to describe

i prvi tip koji želim da opišem

is probing the very big.

je sondiranje izuzetno velikih.

So, how big?

Koliko velikih?

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

Ovo je slika jednog specifičnog galaktičkog jata.

It is so massive that the light passing through it

Ono je toliko masivno da se svetlost koja prolazi kroz njega

is being bent, it's being distorted

savija i krivi

by the extreme gravity of this cluster.

pod ekstremnom gravitacijom ovog jata.

And, in fact, if you look very carefully

Ako pogledate veoma pažljivo

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

videćete prstenove oko ovog jata.

Now, to give you a number,

Kako bih to predstavio brojem,

this particular galaxy cluster

ovo galaktičko jato

has a mass of over one million billion suns.

ima masu preko milion milijardi sunaca.

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

Zapanjujuće je koliko masivni ovi sistemi mogu da budu.

But more than their mass,

Ali osim svoje mase

they have this additional feature.

oni imaju još jednu dodatnu osobinu.

They are essentially isolated systems,

Oni su u suštini izolovani sistemi,

so if we like, we can think of them

i ako želimo, možemo o njima da mislimo

as a scaled-down version of the entire universe.

kao o umanjenoj verziji čitavog univerzuma.

And many of the questions that we might have

I na većinu pitanja koje možemo imati

about the universe at large scales,

o univerzumu na velikim razmerama,

such as, how does gravity work?

kao što je: "Kako fukncioniše gravitacija?"

might be answered by studying these systems.

odgovor možemo dobiti proučavanjem ovih sistema.

So that was very big.

To je bilo veoma veliko.

The second things is very hot.

Druga stvar je veoma toplo.

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

U redu, ako uzmem sliku galaktičkog jata

and I subtract away all of the starlight,

i oduzmem svu svetlost zvezda,

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

ono što mi ostaje je ova velika, plava grudva.

This is in false color.

Ovo nije njena prava boja.

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

Ono što vidimo je svetlost X-zraka.

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

Pitanje je, ako ne potiče od galaksija,

what is emitting this light?

šta emituje ovu svetlost?

The answer is hot gas,

Odgovor je užareni gas,

million-degree gas --

gas na milion stepeni,

in fact, it's plasma.

u stvari, to je plazma.

And the reason why it's so hot

Razlog zbog čega je ovako topao

goes back to the previous slide.

vraća nas na prethodni slajd.

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 velike temperature.

So this is the main idea,

Ovo je glavna ideja,

but science is a rough draft.

ali nauka je samo gruba skica.

There are many basic properties about this plasma

Mnoge osnovne osobine ove plazme

that still confuse us,

nas još uvek zbunjuju,

still puzzle us,

još uvek su nam intrigantne

and still push our understanding

i još uvek menjaju naše razumevanje

of the physics of the very hot.

fizike veoma toplog.

Third thing: probing the very small.

Treća stvar: sondiranje veoma malog.

Now, to explain this, I need to tell you

Kako bih vam ovo objasnio, moram da vam kažem

a very disturbing fact.

jednu veoma uznemirujuću činjenicu.

Most of the universe's matter

Većina materije univerzuma

is not made up of atoms.

nije sačinjena od atoma.

You were lied to.

Lagali su nas.

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

Većina je sačinjena od nečeg veoma, veoma misterioznog

which we call dark matter.

što zovemo tamnom materijom.

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

Tamna materija je nešto što ne voli interakciju,

except through gravity,

osim putem gravitacije

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

i, naravno, voleli bismo da saznamo više o njoj.

If you're a particle physicist,

Ako ste fizičar čestica,

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

želite da znate šta se dešava kada se stvari sudare.

And dark matter is no exception.

I tamna materija nije izuzetak.

Well, how do we do this?

Pa, kako to radimo?

To answer that question,

Kako bih odgovorio na to pitanje, moraću da postavim još jedno,

I'm going to have to ask another one,

which is, what happens when galaxy clusters collide?

a ono je: "Šta se dešava kada se galaktička jata sudare?"

Here is an image.

Evo slike.

Since galaxy clusters are representative

Pošto su galaktička jata reprezentativni

slices of the universe, scaled-down versions.

delovi univerzuma, njegove umanjene verzije,

They are mostly made up of dark matter,

ona su većinom sačinjena od tamne materije

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

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

The red represents the hot gas,

Crvena je užareni gas

and, of course, you can see many galaxies.

i, naravno, vidite mnoštvo galaksija.

What's happened is a particle accelerator

Ono što je nastalo je akcelerator čestica

at a huge, huge scale.

na ogromnoj razmeri.

And this is very important,

I ovo je veoma bitno,

because what it means is that very, very small

jer to znači da veoma, veoma mali efekti

effects that might be difficult to detect in the lab,

koje bi bilo teško detektovati u laboratoriji,

might be compounded and compounded

mogu biti spajani i spajani

into something that we could possibly observe in nature.

u nešto što možemo da posmatramo u prirodi.

So, it's very funny.

Veoma je smešno.

The reason why galaxy clusters

Galaktička jata nas mogu

can teach us about dark matter,

naučiti o tamnoj materiji,

the reason why galaxy clusters

galaktička jata nas mogu

can teach us about the physics of the very small,

naučiti o fizici veoma malog

is precisely because they are so very big.

upravo zato što su ona veoma velika.

Fourth thing: the physics of the very strange.

Četvrta stvar: fizika veoma stranog.

Certainly what I've said so far is crazy.

Ono što sam do sada rekao je zasigurno veoma ludo.

Okay, if there's anything stranger

Ako postoji nešto čudnije

I think it has to be dark energy.

to mora biti tamna energija.

If I throw a ball into the air,

Ako bacim loptu u vazduh,

I expect it to go up.

očekujem da ona poleti.

What I don't expect is that it go up

Ono što ne očekujem je da ona leti

at an ever-increasing rate.

sa sve većim ubrzanjem.

Similarly, cosmologists understand why

Slično tome, kosmolozi razumeju zašto

the universe is expanding.

se univerzum širi.

They don't understand why it's expanding

Ne razumeju zašto se on širi

at an ever-increasing rate.

sa sve većim ubrzanjem.

They give the cause of this

Mogu dati ime uzroku

accelerated expansion a name,

ovog ubrzanog širenja,

and they call it dark energy.

i oni to zovu tamnom energijom.

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

I ponovo, želimo da saznamo više o tome.

So, one particular question that we have is,

Jedno određeno pitanje koje imamo jeste

how does dark energy affect the universe

kako tamna energija utiče na univerzum

at the largest scales?

u najvećoj razmeri?

Depending on how strong it is,

U zavisnosti od njene jačine,

maybe structure forms faster or slower.

moguće je da se strukture formiraju brže ili sporije.

Well, the problem with the large-scale structure

Problem sa strukturama univerzuma na velikim razmerama

of the universe is that it's horribly complicated.

jeste da su one užasno komplikovane.

Here is a computer simulation.

Ovo je kompjuterska simulacija.

And we need a way to simplify it.

Potreban nam je način da ovo pojednostavimo.

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

Volim da mislim o ovome putem analogije.

If I want to understand the sinking of the Titanic,

Ako želim da razumem zašto je Titanik potonuo

the most important thing to do

najvažnija stvar je

is not to model the little positions

ne napraviti model pozicija

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

pojedinačnih delića broda koji su se odlomili.

The most important thing to do is

Najvažnija stvar je

to track the two biggest parts.

ispratiti dva najveća dela.

Similarly, I can learn a lot about the universe

Slično, mogu mnogo da naučim o univezumu

at the largest scales

na najvećoj razmeri

by tracking its biggest pieces

praćenjem njegovih najvećih delova,

and those biggest pieces are clusters of galaxies.

a ti najveći delovi su galaktička jata.

So, as I come to a close,

Kako pristižem kraju,

you might feel slightly cheated.

možda ćete se osetiti prevarenim.

I mean, I began by talking about

Počeo sam priču

how galaxy clusters are useful,

kako su galaktička jata korisna

and I've given some reasons,

i dao sam vam neke razloge zašto,

but what is their use really?

ali šta je zapravo njihova vrednost?

Well, to answer this,

Kako bih odgovorio na ovo,

I want to give you a quote by Henry Ford

želim da vam citiram odgovor Henrija Forda

when he was asked about cars.

kada su ga pitali o automobilima.

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."

rekli bi brže konje."

Today, we as a society are faced

Danas se mi kao društvo suočavamo

with many, many difficult problems.

sa mnogo, mnogo teških problema.

And the solutions to these problems are not obvious.

Rešenja ovih problema nisu očigledna.

They are not faster horses.

Ona nisu brži konji.

They will require an enormous amount of

Ona zahtevaju veliku količinu

scientific ingenuity.

naučne dovitljivosti.

So, yes, we need to focus,

Da, treba da se usredsredimo,

yes, we need to concentrate,

da, treba da se koncentrišemo,

but we also need to remember that

ali takođe moramo i da zapamtimo

innovation, ingenuity, inspiration --

da inovacija, domišljatost, inspiracija -

these things come

ove stvari dolaze

when we broaden our field of vision

kada proširimo naše vidike,

when we step back

kada načinimo korak unazad

when we zoom out.

i udaljimo se.

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

Ne mogu da smislim bolji način za ovo,

by studying the universe around us. Thanks.

od proučavanja univezuma oko nas. Hvala.

(Applause)

(Aplauz)