A few months ago the Nobel Prize in physics was awarded to two teams of astronomers for a discovery that has been hailed as one of the most important astronomical observations ever. And today, after briefly describing what they found, I'm going to tell you about a highly controversial framework for explaining their discovery, namely the possibility that way beyond the Earth, the Milky Way and other distant galaxies, we may find that our universe is not the only universe, but is instead part of a vast complex of universes that we call the multiverse.
Pre nekoliko meseci Nobelovu nagradu iz fizike dobila su dva tima astronoma za otkriće koje je proglašeno jednim od najvažnijih astronomskih zapažanja ikada. Danas, nakon što vam ukratko objasnim šta su našli, pričaću vam o veoma kontraverznom okviru za objašnjavanje njihovog otkrića, naime mogućnost da veoma daleko od Zemlje, Mlečnog puta i ostalih udaljenih galaksija, možemo utvrditi da naš univerzum nije jedini univerzum, već je umesto toga deo ogromnog kompleksa univerzuma koji nazivamo multiverzum.
Now the idea of a multiverse is a strange one. I mean, most of us were raised to believe that the word "universe" means everything. And I say most of us with forethought, as my four-year-old daughter has heard me speak of these ideas since she was born. And last year I was holding her and I said, "Sophia, I love you more than anything in the universe." And she turned to me and said, "Daddy, universe or multiverse?" (Laughter)
Ideja multiverzuma je čudna. Većina nas je odgajana da misli da reč "univerzum" označava sve. Namerno kažem većina nas, jer svojoj četvorogodišnjoj kćeri pričam o ovim idejama od kada se rodila. Prošle godine sam je nosio i rekao: "Sofija, volim te više od svega u univerzumu." Ona me pogledala i rekla: "Tata, u univerzumu ili multiverzumu?" (Smeh)
But barring such an anomalous upbringing, it is strange to imagine other realms separate from ours, most with fundamentally different features, that would rightly be called universes of their own. And yet, speculative though the idea surely is, I aim to convince you that there's reason for taking it seriously, as it just might be right. I'm going to tell the story of the multiverse in three parts. In part one, I'm going to describe those Nobel Prize-winning results and to highlight a profound mystery which those results revealed. In part two, I'll offer a solution to that mystery. It's based on an approach called string theory, and that's where the idea of the multiverse will come into the story. Finally, in part three, I'm going to describe a cosmological theory called inflation, which will pull all the pieces of the story together.
Ali ako izuzmemo takvo nestandardno odgajanje, teško je zamisliti druge svetove odvojene od našeg, većinu sa bitno drugačijim karakteristikama, koji bi sa pravom mogli da se nazovu posebni univerzumi. A ipak, koliko god da je ova ideja spekulativna, moj je cilj da vas ubedim da postoji razlog zašto da je shvatite ozbiljno, pošto možda bude tačna. Ispričaću priču o multiverzumu u tri dela. U prvom delu, opisaću rezultate za koje je dobijena Nobelova nagrada i naglasiću duboku misteriju koju su ti rezultati otkrili. U drugom delu, dajem rešenje ove misterije. Ono se zasniva na pristupu nazvanom teorija struna i tu se ideja o multiverzumu uključuje u ovu priču. Na kraju, u trećem delu, opisaću kosmološku teoriju koja se zove inflacija, koja će spojiti sve delove priče.
Okay, part one starts back in 1929 when the great astronomer Edwin Hubble realized that the distant galaxies were all rushing away from us, establishing that space itself is stretching, it's expanding. Now this was revolutionary. The prevailing wisdom was that on the largest of scales the universe was static. But even so, there was one thing that everyone was certain of: The expansion must be slowing down. That, much as the gravitational pull of the Earth slows the ascent of an apple tossed upward, the gravitational pull of each galaxy on every other must be slowing the expansion of space.
Ok, prvi deo počinje 1929. kada je veliki astronom Edvin Habl shvatio da se sve daleke galaksije brzo udaljavaju od nas i time je utvrdio da se sam svemir širi, da se proširuje. To je bilo nešto revolucionarno. Tada je bilo uvreženo mišljenje da je u najvećoj meri svemir statičan. Ali ipak, u jedno su svi bili sigurni: širenje mora da se usporava. Kao što sila teže Zemlje usporava uspon jabuke bačene uvis, tako sila težnje svake galaksije koja utiče na sve ostale mora da usporava širenje svemira.
Now let's fast-forward to the 1990s when those two teams of astronomers I mentioned at the outset were inspired by this reasoning to measure the rate at which the expansion has been slowing. And they did this by painstaking observations of numerous distant galaxies, allowing them to chart how the expansion rate has changed over time. Here's the surprise: They found that the expansion is not slowing down. Instead they found that it's speeding up, going faster and faster. That's like tossing an apple upward and it goes up faster and faster. Now if you saw an apple do that, you'd want to know why. What's pushing on it?
Sada hajde da uzbrzamo do 1990-ih kada su ta dva tima astronoma koje sam spomenuo na početku, inspirisana ovim razmišljanjem, izmerila stopu po kojoj se širenje usporava. To su učinili mukotrpnim zapažanjima brojnih udaljenih galaksija, što im je omogućilo da prate kako se stopa širenja promenila tokom vremena. I evo iznenađenja: utvrdili su da se širenje ne usporava. Umesto toga utvrdili su da se ubrzava, da je sve brže i brže. To je kao da bacite jabuku na gore i ona se sve više ubrzava. Kada biste videli jabuku da se tako kreće, hteli biste da znate zašto. Šta je gura na gore?
Similarly, the astronomers' results are surely well-deserving of the Nobel Prize, but they raised an analogous question. What force is driving all galaxies to rush away from every other at an ever-quickening speed? Well the most promising answer comes from an old idea of Einstein's. You see, we are all used to gravity being a force that does one thing, pulls objects together. But in Einstein's theory of gravity, his general theory of relativity, gravity can also push things apart.
Slično tome, rezultati astronoma su sigurno zaslužili Nobelovu nagradu, ali postavljaju analogno pitanje. Koja sila utiče na sve galaksije da se međusobno udaljavaju sve većom brzinom? Odgovor koji najviše obećava je stara Ajnštajnova ideja. Vidite, svi smo navikli na gravitaciju kao silu koja radi jednu stvar, međusobno privlači stvari. Ali prema Ajnštajnovoj teoriji gravitacije, njegovoj opštoj teoriji relativiteta, gravitacija može takođe da razdvaja stvari.
How? Well according to Einstein's math, if space is uniformly filled with an invisible energy, sort of like a uniform, invisible mist, then the gravity generated by that mist would be repulsive, repulsive gravity, which is just what we need to explain the observations. Because the repulsive gravity of an invisible energy in space -- we now call it dark energy, but I've made it smokey white here so you can see it -- its repulsive gravity would cause each galaxy to push against every other, driving expansion to speed up, not slow down. And this explanation represents great progress.
Kako? Prema Ajnštajnovoj matematici, ako je svemir uniformno popunjen nevidljivom energijom, nečemu nalik uniformnoj, nevidljivoj magli, onda gravitacija koju ta magla generiše mora da bude odbojna, odbojna gravitacija, što je upravo to što nam treba da objasnimo ova zapažanja. Jer odbojna gravitacija nevidljive energije u svemiru -- koju sada zovemo tamnom energijom, ovde sam je prikazao dimno-belom tako da možete da je vidite - njena odbojna gravitacija bi uticala na to da se svaka galaksija odbija od svih ostalih i tako ubrzava širenje, a ne usporava. I ovo širenje predstavlja veliki napredak.
But I promised you a mystery here in part one. Here it is. When the astronomers worked out how much of this dark energy must be infusing space to account for the cosmic speed up, look at what they found. This number is small. Expressed in the relevant unit, it is spectacularly small. And the mystery is to explain this peculiar number. We want this number to emerge from the laws of physics, but so far no one has found a way to do that.
Ali obećao sam vam misteriju u prvom delu. Evo je. Kada su astronomi izračunali koliko te tamne energije mora da prožima prostor da bi se kosmos ubrzao, otkrili su sledeće. Ovo je mali broj. Izražen u relevantnoj jedinici, on je spektakularno mali. Misterija je objasniti ovaj čudan broj. Želimo da ovaj broj nastane iz zakona fizike, ali do sada to nikome nije uspelo.
Now you might wonder, should you care? Maybe explaining this number is just a technical issue, a technical detail of interest to experts, but of no relevance to anybody else. Well it surely is a technical detail, but some details really matter. Some details provide windows into uncharted realms of reality, and this peculiar number may be doing just that, as the only approach that's so far made headway to explain it invokes the possibility of other universes -- an idea that naturally emerges from string theory, which takes me to part two: string theory.
Možete se zapitati, zašto je to važno? Možda je objašnjenje ovog broja samo tehničko pitanje, tehnički podatak zanimljiv stručnjacima, bez važnosti za nas ostale. To svakako jeste tehnički podatak, ali neki podaci stvarno jesu važni. Neki podaci daju uvid u neistražene svetove realnosti i ovaj čudan broj možda upravo to čini, jer kao jedini način koji je do sada to uspešno objašnjavao, poziva se na mogućnost postojanja drugih univerzuma - ideja koja prirodno proističe iz teorije struna, što me uvodi u drugi deo: teoriju struna.
So hold the mystery of the dark energy in the back of your mind as I now go on to tell you three key things about string theory. First off, what is it? Well it's an approach to realize Einstein's dream of a unified theory of physics, a single overarching framework that would be able to describe all the forces at work in the universe. And the central idea of string theory is quite straightforward. It says that if you examine any piece of matter ever more finely, at first you'll find molecules and then you'll find atoms and subatomic particles. But the theory says that if you could probe smaller, much smaller than we can with existing technology, you'd find something else inside these particles -- a little tiny vibrating filament of energy, a little tiny vibrating string. And just like the strings on a violin, they can vibrate in different patterns producing different musical notes. These little fundamental strings, when they vibrate in different patterns, they produce different kinds of particles -- so electrons, quarks, neutrinos, photons, all other particles would be united into a single framework, as they would all arise from vibrating strings. It's a compelling picture, a kind of cosmic symphony, where all the richness that we see in the world around us emerges from the music that these little, tiny strings can play.
Zato nemojte zaboraviti negde u pozadini misteriju tamne materije, dok vam budem pričao o tri ključne stvari teorije struna. Kao prvo, šta je to? To je pristup ka ostvarivanju Ajnštanovog sna o jedinstvenoj teoriji u fizici, jednom sveobuhvatnom okviru koji bi mogao da opiše sve sile koje deluju u univerzumu. Centralna ideja teorije struna je prilično jednostavna. Ona kaže da ako ispitujete bilo koji delić materije sve detaljnije, prvo ćete naći molekule, a onda atome i subatomske čestice. Prema ovoj teoriji, ako biste mogli da ispitujete još sitnije nego što možemo postojećom tehnologijom, našli biste još nešto u ovim česticama - sićušno, vibrirajuće vlakno energije, sićušnu vibrirajuću strunu. I baš kao strune na violini, one mogu da vibriraju na različite načine proizvodeći različite muzičke note. Ove male fundamentalne strune, kada vibriraju na različite načine, proizvode različite vrste čestica -- tako se elektroni, kvarkovi, neutrini, fotoni, sve ostale čestice ujedinjuju u jedan okvir, pošto svi proističu iz vibrirajućih struna. To je zanimljiva slika, neke vrste kosmičke simfonije, gde svo bogatstvo koje vidimo u svetu oko nas nastaje iz muzike koje ove sićušne strune mogu da sviraju.
But there's a cost to this elegant unification, because years of research have shown that the math of string theory doesn't quite work. It has internal inconsistencies, unless we allow for something wholly unfamiliar -- extra dimensions of space. That is, we all know about the usual three dimensions of space. And you can think about those as height, width and depth. But string theory says that, on fantastically small scales, there are additional dimensions crumpled to a tiny size so small that we have not detected them. But even though the dimensions are hidden, they would have an impact on things that we can observe because the shape of the extra dimensions constrains how the strings can vibrate. And in string theory, vibration determines everything. So particle masses, the strengths of forces, and most importantly, the amount of dark energy would be determined by the shape of the extra dimensions. So if we knew the shape of the extra dimensions, we should be able to calculate these features, calculate the amount of dark energy.
Ali postoji cena ovog elegantnog ujedinjenja jer su godine istraživanja pokazale da matematika teorije struna ne funkcioniše baš sasvim. Postoje interne nedoslednosti, osim ako dopustimo nešto potpuno nepoznato -- dodatne dimenzije prostora. Svi znamo za tri standardne dimenzije prostora. Možete ih zamisliti kao visinu, širinu i dubinu. Ali teorija struna kaže da na fantastično maloj skali, postoje dodatne dimenzije zgužvane na tako malu veličinu da ih nismo detektovali. Ali čak iako su dimenzije skrivene, one bi uticale na stvari koje možemo primetiti jer oblik dodatnih dimenzija ograničava kako strune vibriraju. A u teoriji struna, vibracije određuju sve. Tako bi masa čestica, jačina sila i najvažnije, količina tamne materije bila određena oblikom dodatnih dimenzija. Zato kada bismo znali oblik dodatnih dimenzija, mogli bismo da izračunamo te karakteristike, da izračunamo količinu tamne energije.
The challenge is we don't know the shape of the extra dimensions. All we have is a list of candidate shapes allowed by the math. Now when these ideas were first developed, there were only about five different candidate shapes, so you can imagine analyzing them one-by-one to determine if any yield the physical features we observe. But over time the list grew as researchers found other candidate shapes. From five, the number grew into the hundreds and then the thousands -- A large, but still manageable, collection to analyze, since after all, graduate students need something to do. But then the list continued to grow into the millions and the billions, until today. The list of candidate shapes has soared to about 10 to the 500.
Izazov je u tome što ne znamo oblik dodatnih dimenzija. Sve što imamo je spisak kandidata oblika koje dopušta matematika. Kada su ove ideje pri put razvijene, bilo je samo oko pet različitih kandidata za oblike, pa možete zamisliti da ih analizirate jednog po jednog kako biste utvrdili da li neki daje fizičke karakteristike koje smo zapazili. Ali tokom vremena spisak se uvećao jer su istraživači našli još kandidata za oblike. Sa pet, broj je porastao na stotine i onda hiljade - Što je veliki skup, ali koji se ipak može analizirati jer ipak i postdiplomci moraju nešto da rade. A onda je spisak nastavio da raste na milione i milijarde, do danas. Spisak kandidata za oblike je otišao za oko 10 na 500.
So, what to do? Well some researchers lost heart, concluding that was so many candidate shapes for the extra dimensions, each giving rise to different physical features, string theory would never make definitive, testable predictions. But others turned this issue on its head, taking us to the possibility of a multiverse. Here's the idea. Maybe each of these shapes is on an equal footing with every other. Each is as real as every other, in the sense that there are many universes, each with a different shape, for the extra dimensions. And this radical proposal has a profound impact on this mystery: the amount of dark energy revealed by the Nobel Prize-winning results.
I šta sada? Neki istraživači su se obeshrabrili i zaključili da sa toliko kandidata za oblike dodatnih dimenzija, gde svaki daje različite fizičke karakteristike, teorija struna nikada neće dati konačna predviđanja koja se mogu testirati. Ali drugi su obrnuli ovaj problem naglavačke i uveli mogućnost multiverzuma. Evo ideje. Možda je svaki od ovih oblika jednak svim ostalima. Svaki je realan kao i svaki drugi, u smislu da postoje mnogi univerzumi, svi različitog oblika, za dodatne dimenzije. Ovaj radikalni predlog je imao dubok uticaj na ovu misteriju: količinu tamne energije koju su otkrili rezultati za dobijenu Nobelovu nagradu.
Because you see, if there are other universes, and if those universes each have, say, a different shape for the extra dimensions, then the physical features of each universe will be different, and in particular, the amount of dark energy in each universe will be different. Which means that the mystery of explaining the amount of dark energy we've now measured would take on a wholly different character. In this context, the laws of physics can't explain one number for the dark energy because there isn't just one number, there are many numbers. Which means we have been asking the wrong question. It's that the right question to ask is, why do we humans find ourselves in a universe with a particular amount of dark energy we've measured instead of any of the other possibilities that are out there?
Jer vidite, ako postoje drugi univerzumi i ako svaki taj univerzum ima različit oblik za dodatne dimenzije, onda će fizičke karakteristike svakog univerzuma biti različite i konkretno, količina tamne energije u svakom univerzumu će se razlikovati. Što znači da bi misterija objašnjenja količine tamne energije koju smo sada izmerili imala potpuno drugačiji karakter. U ovom kontekstu, zakoni fizike ne mogu da objasne jedan broj za tamnu materiju jer ne postoji samo jedan broj, ima mnogo brojeva. To znači da smo postavljali pogrešno pitanje. Pravo pitanje koje treba postaviti jeste, zašto se mi ljudi nalazimo u univerzumu sa određenom količinom tamne materije koju smo izmerili umesto bilo koje druge mogućnosti koja postoji?
And that's a question on which we can make headway. Because those universes that have much more dark energy than ours, whenever matter tries to clump into galaxies, the repulsive push of the dark energy is so strong that it blows the clump apart and galaxies don't form. And in those universes that have much less dark energy, well they collapse back on themselves so quickly that, again, galaxies don't form. And without galaxies, there are no stars, no planets and no chance for our form of life to exist in those other universes.
To je pitanje sa kojim možemo da napredujemo. Jer u tim univerzumima koji imaju mnogo više tamne energije od naše, kad god materija proba da se grupiše u galaksije, snaga odbijanja tamne energije je toliko jaka da razbija tu gomilu i galaksije se ne formiraju. U tim univerzumima koji imaju mnogo manje tamne energije, dolazi do unutrašnjeg kolapsa tako brzo da se galaksije opet ne formiraju. Bez galaksija, nema zvezda, nema planeta i nema šanse da naš oblik života postoji u tim drugim univerzumima.
So we find ourselves in a universe with the particular amount of dark energy we've measured simply because our universe has conditions hospitable to our form of life. And that would be that. Mystery solved, multiverse found. Now some find this explanation unsatisfying. We're used to physics giving us definitive explanations for the features we observe. But the point is, if the feature you're observing can and does take on a wide variety of different values across the wider landscape of reality, then thinking one explanation for a particular value is simply misguided.
Zato se nalazimo u univerzumu sa određenom količinom tamne energije koju smo izmerili prosto zato što naš univerzum ima uslove koji su pogodni za naš oblik života. To bi bilo to. Misterija rešena, multiverzum nađen. Neki nisu zadovoljni ovim objašnjenjem. Navikli smo da nam fizika daje konačna objašnjenja odlika koje opažamo. Ali poenta je u tome, da ako odlika koju zapažate može da ima i ima niz različitih vrednosti u širokom predelu realnosti, onda razmišljanje o jednom objašnjenju za određnu vrednost je jednostavno neispravno.
An early example comes from the great astronomer Johannes Kepler who was obsessed with understanding a different number -- why the Sun is 93 million miles away from the Earth. And he worked for decades trying to explain this number, but he never succeeded, and we know why. Kepler was asking the wrong question.
Rani primer dolazi od velikog astronoma Johana Keplera koji je bio opsednut razumevanjem jednog drugog broja - zašto je Sunce udaljeno 150 miliona km od Zemlje. Decenijama je pokušavao da objasni ovaj broj, ali nikada nije uspeo i znamo zašto. Kepler je postavljao pogrešno pitanje.
We now know that there are many planets at a wide variety of different distances from their host stars. So hoping that the laws of physics will explain one particular number, 93 million miles, well that is simply wrongheaded. Instead the right question to ask is, why do we humans find ourselves on a planet at this particular distance, instead of any of the other possibilities? And again, that's a question we can answer. Those planets which are much closer to a star like the Sun would be so hot that our form of life wouldn't exist. And those planets that are much farther away from the star, well they're so cold that, again, our form of life would not take hold. So we find ourselves on a planet at this particular distance simply because it yields conditions vital to our form of life. And when it comes to planets and their distances, this clearly is the right kind of reasoning. The point is, when it comes to universes and the dark energy that they contain, it may also be the right kind of reasoning.
Sada znamo da postoje mnoge planete koje su na različitim rastojanjima od svojih matičnih zvezda. Zato je nadanje da će zakoni fizike objasniti jedan određeni broj, 150 miliona km, jednostavno pogrešno. Umesto toga pravo pitanje jeste, zašto se ljudi nalaze na planeti, na određenoj udaljenosti, umesto svih ostalih mogućnosti? I opet, to je pitanje na koje možemo da odgovorimo. Sve one planete koje su mnogo bliže zvezdi poput Sunca bile bi toliko tople da naš oblik života ne bi postojao. A one planete koje su mnogo dalje od zvezde, one su toliko hladne da naš oblik života ne bi mogao da opstane. Tako da se nalazimo na planeti pri ovoj određenoj udaljenosti prosto jer nam daje uslove ključne za naš oblik života. A kada su u pitanju planete i njihova udaljenost, ovo je očigledno ispravan način razmišljanja. Poenta je, da kada su u pitanju univerzumi i tamna energija koju sadrže, to takođe može biti ispravan način razmišljanja.
One key difference, of course, is we know that there are other planets out there, but so far I've only speculated on the possibility that there might be other universes. So to pull it all together, we need a mechanism that can actually generate other universes. And that takes me to my final part, part three. Because such a mechanism has been found by cosmologists trying to understand the Big Bang. You see, when we speak of the Big Bang, we often have an image of a kind of cosmic explosion that created our universe and set space rushing outward.
Jedna ključna razlika, naravno, jeste da znamo da postoji još planeta, ali do sada smo samo spekulisali o mogućnosti da postoje drugi univerzumi. Znači da bismo sve spojili, potreban nam je mehanizam koji stvarno generiše druge univerzume. To me dovodi do mog konačnog dela, trećeg dela. Jer su takav mehanizam pronašli kosmolozi koji pokušavaju da razumeju Veliki prasak. Vidite, kada govorimo o Velikom prasku, često imamo sliku neke kosmičke eksplozije koja je stvorila univerzum i izbacila svemir napolje.
But there's a little secret. The Big Bang leaves out something pretty important, the Bang. It tells us how the universe evolved after the Bang, but gives us no insight into what would have powered the Bang itself. And this gap was finally filled by an enhanced version of the Big Bang theory. It's called inflationary cosmology, which identified a particular kind of fuel that would naturally generate an outward rush of space. The fuel is based on something called a quantum field, but the only detail that matters for us is that this fuel proves to be so efficient that it's virtually impossible to use it all up, which means in the inflationary theory, the Big Bang giving rise to our universe is likely not a one-time event. Instead the fuel not only generated our Big Bang, but it would also generate countless other Big Bangs, each giving rise to its own separate universe with our universe becoming but one bubble in a grand cosmic bubble bath of universes.
Ali postoji mala tajna. Veliki prasak izostavlja nešto veoma važno, prasak. On nam govori o tome kako se univerzum razvio nakon praska, ali nam ne daje uvid u to šta je dalo energiju samom prasku. A ova rupa je konačno popunjena boljom verzijom teorije Velikog praska. Zove se inflatorna kosmologija, koja je identifikovala određenu vrstu goriva koje bi prirodno generisalo izbijanje prostora ka spolja. Gorivo se zasniva na nečemu nazvanom kvantno polje, ali jedini podatak koji nam je važan jeste da je ovo gorivo toliko efikasno da je praktično nemoguće da se sve potroši, što znači da prema inflatornoj teoriji, Veliki prasak koji je stvorio naš univerzum verovatno nije jedinstveni događaj. Umesto toga gorivo je generisalo ne samo naš Veliki prasak, već i bezbroj drugih Velikih praskova, svaki bi stvorio svoj posebni univerzum, a naš univerzum bi bio samo jedan mehur u velikoj kosmičkoj peni za kupanje univerzuma.
And now, when we meld this with string theory, here's the picture we're led to. Each of these universes has extra dimensions. The extra dimensions take on a wide variety of different shapes. The different shapes yield different physical features. And we find ourselves in one universe instead of another simply because it's only in our universe that the physical features, like the amount of dark energy, are right for our form of life to take hold. And this is the compelling but highly controversial picture of the wider cosmos that cutting-edge observation and theory have now led us to seriously consider.
Sada, kada spojimo ovo sa teorijom struna, evo slike do koje dolazimo. Svaki od ovih univerzuma ima dodatne dimenizije. Ekstra dimenzije imaju niz različitih oblika. Različiti oblici daju različite fizičke odlike. I mi smo u jednom univerzumu umesto u drugom, jednostavno jer su samo u našem univerzumu fizičke odlike, kao što je količina tamne energije, pogodne za razvoj našeg oblika života. Ovo je zanimljiva, ali veoma kontroverzna slika šireg kosmosa koju su nas najnovija zapažanja i teorija naterali da ozbiljno razmotrimo.
One big remaining question, of course, is, could we ever confirm the existence of other universes? Well let me describe one way that might one day happen. The inflationary theory already has strong observational support. Because the theory predicts that the Big Bang would have been so intense that as space rapidly expanded, tiny quantum jitters from the micro world would have been stretched out to the macro world, yielding a distinctive fingerprint, a pattern of slightly hotter spots and slightly colder spots, across space, which powerful telescopes have now observed. Going further, if there are other universes, the theory predicts that every so often those universes can collide. And if our universe got hit by another, that collision would generate an additional subtle pattern of temperature variations across space that we might one day be able to detect. And so exotic as this picture is, it may one day be grounded in observations, establishing the existence of other universes.
Ostaje jedno veliko pitanje, a to je, da li bismo ikada mogli da potvrdimo postojanje drugih univerzuma? Objasniću vam jedan način na koji bi to moglo da se dogodi. Inflaciona teorija već ima jaku podršku iz zapažanja. Jer teorija predviđa da bi Veliki prasak bio toliko intenzivan da bi se dok se svemir brzo širio, sićušni kvantni titraji mikro sveta proširli u makro svet, dajući upadljiv otisak, raspored blago toplijih tačaka i blago hladnijih tačaka, širom svemira, koji su sada zapazili jaki teleskopi. Ako idemo dalje, ako postoji još univerzuma, teorija predviđa da se svako malo ti univerzumi mogu sudariti. I ako bi naš univerzum udario drugi, taj sudar bi stvorio dodatan suptilan raspored temperaturnih varijacija širom svemira koje bismo mogli jednog dana da detektujemo. I ma koliko ova slika bila egzotična, jednog dana bi mogla biti zasnovana na opservacijama, utvrđujući postojanje drugih univerzuma.
I'll conclude with a striking implication of all these ideas for the very far future. You see, we learned that our universe is not static, that space is expanding, that that expansion is speeding up and that there might be other universes all by carefully examining faint pinpoints of starlight coming to us from distant galaxies. But because the expansion is speeding up, in the very far future, those galaxies will rush away so far and so fast that we won't be able to see them -- not because of technological limitations, but because of the laws of physics. The light those galaxies emit, even traveling at the fastest speed, the speed of light, will not be able to overcome the ever-widening gulf between us. So astronomers in the far future looking out into deep space will see nothing but an endless stretch of static, inky, black stillness. And they will conclude that the universe is static and unchanging and populated by a single central oasis of matter that they inhabit -- a picture of the cosmos that we definitively know to be wrong.
Završiću sa bitnim implikacijama svih ovih ideja za veoma daleku budućnost. Vidite, naučili smo da naš univerzum nije statičan, da se svemir širi, da se to širenje ubrzava i da možda postoji još univerzuma samo pažljivim pregledanjem slabašnih tačaka zvezdanog svetla koje dolazi do nas iz udaljenih galaksija. Pošto se širenje ubrzava, u veoma dalekoj budućnosti te galaksije će se udaljiti toliko daleko i toliko brzo da nećemo moći da ih vidimo - ne zbog tehnoloških ograničenja, već zbog zakona fizike. Svetlost koju te galaksije emituju, čak i kada putuju pri najbržoj brzini, brzini svetlosti, neće moći da premosti sve veći jaz između nas. Zato astronomi u dalekoj budućnosti koji gledaju u dalek svemir neće videti ništa osim beskonačnog prostranstva statične, mastiljave, crne tišine. Oni će zaključiti da je univerzum statičan i nepromenljiv i nastanjen jednom centralnom oazom materije koju oni nastanjuju - slika kosmosa za koju definitivno znamo da je pogrešna.
Now maybe those future astronomers will have records handed down from an earlier era, like ours, attesting to an expanding cosmos teeming with galaxies. But would those future astronomers believe such ancient knowledge? Or would they believe in the black, static empty universe that their own state-of-the-art observations reveal? I suspect the latter. Which means that we are living through a remarkably privileged era when certain deep truths about the cosmos are still within reach of the human spirit of exploration. It appears that it may not always be that way. Because today's astronomers, by turning powerful telescopes to the sky, have captured a handful of starkly informative photons -- a kind of cosmic telegram billions of years in transit. and the message echoing across the ages is clear. Sometimes nature guards her secrets with the unbreakable grip of physical law. Sometimes the true nature of reality beckons from just beyond the horizon.
Možda će ti budući astronomi imati dokaze prenete iz ranijeg doba, poput našeg, koji potvrđuju da se kosmos širi prepun galaksija. Ali da li će ti budući astronomi verovati u to drevno znanje? Ili će verovati u crni, statični prazni univerzum koji pokazuju njihova najnovija zapažanja? Nagađam da će biti ovo drugo. Što znači da živimo u izuzetno privilegovanom dobu, u kome su neke suštinske istine o kosmosu i dalje na dohvat ljudskog istraživačkog duha. Izgleda da možda neće uvek biti tako. Jer današnji astronomi su, usmeravajući jake teleskope ka nebu, uhvatili nekolicinu veoma informativnih fotona - vrstu kosmičkog telegrama milijardi godina u tranzitu. Poruka koja odzvanja kroz vekove je jasna. Nekada priroda štiti svoje tajne čvrstom rukom fizičkog zakona. Nekada nas prava priroda realnosti doziva negde preko horizonta.
Thank you very much.
Hvala vam puno.
(Applause)
(Aplauz)
Chris Anderson: Brian, thank you. The range of ideas you've just spoken about are dizzying, exhilarating, incredible. How do you think of where cosmology is now, in a sort of historical side? Are we in the middle of something unusual historically in your opinion?
Kris Anderson: Brajane, hvala ti. Raspon ideja o kojima si nam pričao je vrtoglav, uzbudljiv, neverovatan. Gde misliš da je kosmologija sada, sa istorijskog aspekta? Da li smo usred nečega istorijski neobičnog, prema tebi?
BG: Well it's hard to say. When we learn that astronomers of the far future may not have enough information to figure things out, the natural question is, maybe we're already in that position and certain deep, critical features of the universe already have escaped our ability to understand because of how cosmology evolves. So from that perspective, maybe we will always be asking questions and never be able to fully answer them.
BG: Teško je reći. Kada saznamo da astronomi u dalekoj budućnosti možda neće imati dovoljno informacija da saznaju stvari, postavlja se pitanje, možda smo već u toj poziciji i neke duboke, ključne odlike univerzuma su već utekle našoj sposobnosti da ih razumemo zbog načina na koji se kosmologija razvija. Iz te perspektive, možda ćemo uvek postavljati pitanja i nikada nećemo moći u potpunosti da ih razumemo.
On the other hand, we now can understand how old the universe is. We can understand how to understand the data from the microwave background radiation that was set down 13.72 billion years ago -- and yet, we can do calculations today to predict how it will look and it matches. Holy cow! That's just amazing. So on the one hand, it's just incredible where we've gotten, but who knows what sort of blocks we may find in the future.
Sa druge strane, sada možemo da razumemo koliko je star univerzum. Možemo razumeti kako da razumemo podatke mikrotalasnog pozadinskog zračenja koje je poslato pre 13,72 milijardi godina - danas možemo da izračunamo kako da predvidimo kako će izgledati i poklapa se. Tako mi svega! To je neverovatno. Sa jedne strane, potpuno je neverovatno dokle smo stigli, ali ko zna na kakve prepreke možemo naići u budućnosti.
CA: You're going to be around for the next few days. Maybe some of these conversations can continue. Thank you. Thank you, Brian. (BG: My pleasure.)
KA: Ti ćeš biti tu narednih par dana. Možda se neki od ovih razgovora mogu nastaviti. Hvala ti. Hvala ti, Brajane. (BG: Bilo mi je zadovoljstvo.)
(Applause)
(Aplauz)