Welcome one and all! It’s time to grab your seat for the biggest battle in the soon-to-be-formed universe. That’s right— the Big Bang is about to go down! In one corner is the force that brings all matter together. It acts on any particle with mass, and its range is infinite— give it up for gravity! In the other corner, our contender can push matter away with spectacular strength. When the going gets tough, this fighter just gets tougher. That’s right, it’s pressure!
Svi vi, dobro došli! Vreme je da zauzmete mesta za najveću bitku u univerzumu u nastajanju. Tako je - Veliki prasak samo što nije počeo! U jednom uglu je sila koja drži svu materiju na okupu. Deluje na sve čestice sa masom i njen opseg je beskonačan - pozdravite gravitaciju! U drugom uglu, naš izazivač odguruje materiju spektakularnom snagom. Kada postane jako teško, naš borac postaje još jači. Tako je, on je pritisak!
Over the next several hundred thousand years, these two contenders will be wrestling for the fate of the universe. That’s right folks, the ripple effects of this historic match will shape the structure of the universe as we know it today. But what are these powers fighting over? We’ll find out when the Big Bang hits right... now!
U narednih nekoliko stotina hiljada godina, ova dva izazivača će se rvati za sudbinu univerzuma. Tako je, narode, udarni talasi ovog istorijskog meča oblikovaće strukturu univerzuma kakvog znamo danas. Međutim, oko čega se ove sile bore? Saznaćemo kada Veliki prasak otpočne upravo... sad!
Let’s zoom in for the play-by-play.
Zumirajmo rundu po rundu.
This epic event has brought three components into our infant universe. Dark matter, which only interacts with gravity. Baryonic matter, which makes up all matter you’ve ever seen, is affected by both gravity and pressure. And radiation composed of innumerable particles of light, also known as photons.
Epski događaj je uveo tri komponente u naš univerzum u povoju. Tamnu materiju, koja jedino interaguje sa gravitacijom. Barionsku materiju, koja sačinjava svu materiju koju ste ikad videli, i na koju utiče kako gravitacija tako i pritisak. I radijaciju koja se sastoji od bezbroj čestica svetlosti, poznatih i kao fotoni.
In the moments just after the Big Bang, all three components are in equilibrium, meaning no one location is denser than another. But as the universe starts expanding, differences in density start to emerge. Gravity immediately gets to work pulling matter together. Dark matter begins to collect at the center of these increasingly dense regions, forming the foundations of future galaxies.
U trenucima neposredno nakon Velikog praska sve tri komponente su bile u ravnoteži, a to znači da nijedno mesto nije bilo gušće od drugog. Kako univerzum pak počinje da se širi, razlike u gustini iskrsavaju. Gravitacija se istog trena baca na posao zbijajući materiju. Tamna materija počinje da se skuplja u središtu ovih sve gušćih oblasti, formirajući osnove budućih galaksija.
Meanwhile, pressure begins gathering its strength. In this hot, high-energy environment, protons and electrons can’t come together to form atoms, so these loose particles zip around, freely interacting with ambient photons. The result is almost a fluid of baryonic matter and radiation. But the closer these baryonic particles get, the hotter the fluid becomes, pushing photons to ping around with incredible force. This is the power of pressure, specifically radiation pressure, battling to push things apart.
U međuvremenu, pritisak počinje da sakuplja snagu. U ovoj vreloj, visokoenergetskoj sredini, protoni i elektroni ne mogu da se spoje i stvore atome, te ove slobodne čestice jure uokolo, slobodno interagujući sa okolnim fotonima. Rezultat gotovo da je tečnost od barionske materije i radijacije. Kako pak ove barionske čestice postaju bliže, tečnost postaje vrelija, terajući fotone da skakuću okolo neverovatno silovito. Ovo je snaga pritiska, to jest svetlosnog pritiska, koji se bori da stvari drži razdvojene.
With each of gravity’s vicious tugs squeezing photons and matter together, pressure exerts a forceful shove back. And as the two giants struggle, they heave this fluid back and forth— creating massive waves called baryonic acoustic oscillations. Moving at almost two thirds the speed of light these BAOs ripple across space, impacting the universe on the biggest scale imaginable. These rolling waves determine the distribution of matter throughout space, meaning that today— almost 14 billion years after this fight began— we're more likely to find galaxies at their peaks and empty space in their troughs. And that’s not all. We can still see these ripples in the background radiation of the universe, a permanent reminder of this epic brawl.
Sa svakim žestokim stezanjem gravitacije koja zbija fotone i materiju zajedno, pritisak izvodi silovit potisak. I kako se dva džina bore, guraju ovu tečnost napred i nazad - stvarajući masivne talase koji se nazivaju barionskim akustičnim oscilacijama. Krećući se skoro dve trećine brzine svetlosti, ovi BAO-i se talasaju svemirom, utičući na univerzum u najvećoj mogućoj razmeri. Ovi kotrljajući talasi određuju preraspodelu materije kroz svemir, što znači da danas - skoro 14 milijardi godina nakon početka ove borbe - najveće su nam šanse da nađemo galaksije na bregovima talasa, a prazan prostor u dolama talasa. I to nije sve. I dalje možemo da vidimo ovo talasanje kao pozadinu radijacije u univerzumu, trajni podsetnik na ovu epsku bitku.
But after being locked in a stalemate for roughly 370,000 years, the tide of our battle finally begins to turn. After all this time, the heat from the Big Bang has dissipated significantly, cooling the universe down to a temperature at which loose electrons start to pair up with protons. Known as the “era of recombination,” this stops electrons from recklessly pinging around. This allows light to stream freely for the first time, illuminating the universe. These photons now only exert a tiny force on the neutral atoms they interact with, gradually reducing the power of pressure.
Međutim, nakon učaurenosti u pat poziciji oko 370 000 godina, struje naše bitke konačno počinju da se menjaju. Posle sveg ovog vremena, toplota nastala u Velikom prasku se značajno raspršila, rashlađujući univerzum do temperature u kojoj ovi slobodni elektroni počinju da se sparuju sa protonima. Poznata kao „era rekombinacije”, sprečava elektrone da bezobzirno skakuću okolo. I omogućuje svetlosti da slobodno poteče prvi put, osvetljujući univerzum. Ovi fotoni sad ispoljavaju sićušnu silu na neutralne atome sa kojima interaguju, vremenom umanjujući snagu pritiska.
And with that, it’s time to crown our champion! The undefeated force, the most pervasive power in the universe: it’s gravity! And yet, this rivalry isn’t over. A similar battle continues between these two sworn enemies today, within every single star. As gravity pulls a star’s gas inward, pressure increases and pushes the matter back outward. This push and pull keeps the Sun, and all other stars, stable for billions of years. In fact, this clash of the titans is the same reason Earth’s atmosphere doesn’t collapse to the ground. So while their greatest fight might have ended, these two warriors are still to be locked in combat— even as a new challenger approaches.
I samim tim je vreme da krunišemo našeg šampiona! Neporaženu silu, najprodorniju snagu u univerzumu: gravitaciju! Pa ipak, ovde se rivalstvo ne završava. Danas se slična bitka između ovih zakletih neprijatelja nastavlja unutar svake zvezde. Kako gravitacija vuče zvezdani gas unutra, pritisak se uvećava i gura materiju nazad ka spolja. Ovo privlačenje i guranje održava Sunce i sve ostale zvezde stabilnim milijardama godina. Zapravo, upravo je sudar titana razlog zašto se zemljina atmosfera ne sruši na tlo. Stoga, ikao je njihova najveća bitka možda okončana, ova dva ratnika će i dalje da budu u klinču borbe - čak i dok se novi izazivač približava.