What Happened Before the Big Bang? 

I literally can't believe that PBS actually is funding something this in-detail. I used to watch PBS as a kid all the time, it's what got me interested in science and why I went into STEM. I love you guys so much, you are doing a huge service to humanity, inspiring multiple generations to have an interest in sciences which will make this world better for everyone. Thank you so much for the endless joy you've brought us :') You have no idea how much it means to me

I watch an episode when I start feeling too smart... Always brings back me to reality...

With all these people saying they didn't understand anything, I'd just like to say that I really appreciate your level of depth. This channel has some of the best pop-sci explanations of theoretical physics and cosmology out there. Thank you so much Matt (and anyone else involved)!

Yesterday I looked at my dog in pity. Unable to comprehend television....he deserves an extra treat today

who gets totally confused half way through but just keeps watching anyway?

Sometimes I watch these videos and realize: “so this is what it feels not to understand English “

I feel these videos are a really convoluted way of saying "we just don't know, although a couple of physicists have some good ideas"

1. Question in my head: "What Happened Before the Big Bang?" 2. Watching this video. 3. Don't understand anything. 4. Tell myself to stop asking questions that have too complicated answers.

Love the fact that PBS is covering ground breaking theoretical research in somewhat comprehendible human. Support them if you can.

I feel like I'm in the classroom with Charlie Brown listening to the teacher

I’m hoping if i watch enough of these videos I’ll understand what he’s talking about

Me: watches this video Also me: can’t understand the cooking instructions on the pogo box

I have a degree in physics and chemistry, he lost me.

I think a more fun question is, what is on the other side of the universes expansion? We know it's expanding. But, expanding into what exactly?

9:48 "Admittedly this raises a few questions." Bro... you have no idea...

I love Spacetime. Best channel covering cosmology and particle physics. All other documentries on YT are just crap.

Props to the background artists. I just noticed the parallaxing on the stars in the background when the camera moves. Not easy to do that with a constantly changing background

The visual explanations are amazing and something a textbook can never bring.

This channel is one of the main reasons I want to research in astrophysics as a machine learning student

Don't let him out again! We need these Space Time episodes.

just getting back into this channel. i remember getting upset 3 or 4 years ago when i saw gabe was getting replaced, and now i'll be devastated if matt ever has to go! really doing an awesome job! thanks for all the knowledge (even if it doesn't ever fully sink in!)

This show never fails to thoroughly blow my mind.

I absolutely love the slow roll inflation theory. There's something profoundly comforting in the sentiment that nothing ever really ends in that model of the universe. Yes it still implies that this particular bubble will expand forever and eventually succumb to heat death, but that won't be the end of everything for everyone.

3 tabs acid and Spacetime... gets you really thinking fast

I love not only understanding his videos but also noticing the inner jokes and sarcasms he throws all around in such a subtle way The way these videos are produced is absolutely fantastic and extraordinary

When you think you understand anything Space Time: "hold my beer"

You know what blows my mind the most... why is there anything at all? Surely the easiest thing would have been for nothing to exist AT ALL. Nothing EVER. A literal lack of anything would be simpler than all the crazy stuff that goes on. But yet here we are talking about it. The fact that anything exists at all will always be the weirdest thing to me.

I would undoubtably Not get his April fools joke.. He could even have been making up facts for the last year while i still silently Stare and nodd

I understood 10% of everything he said. I still watched to the end for some reason :)

"We dont know" is the only answer.

I've been studying astrophysics since the 7th grade. I'm now 37 and this was way over my head. Lol!

I need colored animations and detailed physics of the time before time.

Been waiting 2 years for this video. Thanks so much for finally presenting the topic. This channel is the best! Seen every episode twice. Thanks.

"The day without yesterday."

Was that the first time in YT history that a Creator had a "wanted to have a quick word" that wasn't about a sponsor?

"Hot dense expanding state." That's me when I eat spicy food.

The Homer voice in my head is saying "just tell me what happened before the big bang!"

No, that isn't the idea of the question. You're still talking about the Big Bang. The question is what happened before. You might say that there is no time before the big bang. OK, then what was there before time began.

I'm halfway through and simply want to comment that I appreciate the use of speculative terminology such as "could" and "might"...it goes a long way in allowing for civil & productive discussion/debate of the hypotheses. :)

I would be lying if I say, I understand this whole thing...

Is it just me or do you get chills realizing your a human

I watch these types of videos when I cant sleep at night.

When bubbles collide is my favorite Powerman 500 remake

"ok, cool story bro" At least I understood that part!

I have a question: Can we theorize whether these infinitely spawned universes have the same laws of physics within them or would this be totally random? I would imagine if some sort of physics ties our universe to others there would be boundaries that would limit variation.

Im just a guy from East Tennessee, it sounds like y'all are proposing a perpetual motion phenomena. I was under the impression that's not plausible. Love the information.

Watching PBS Space Time for a long time and this is now one of my favorite episodes! Great idea, that requires and drives up a lot of imagination in different imaginative scenarios.(Had to watch it twice though :D) Thanks guys, keep it going!

um...2Min in, and I already need to look up so many words and phrases.

This channel is starting to sound more and more like a Star Trek Next Generation episode. All we need now are some subspace fields. And tachyons.

You say you don't know where the speck started, but how was this speck here in the first place?

Fantastic. I remember mentioning inflatons and scalar fields in a video maybe 2 or 3 years ago now (I've forgotten, been following PBS since before Matt took over) and he mentioned in the following video that he would eventually "get to that" and I held him to it. Seems today's the day. Well played, Mr O'Dowd!

1:27 I was expecting "...in an eternally inflating - SPACETIME". It felt like the end of the episode and I was thinking "Wait, that was quick."

Everybody gangsta till the Universes start poppin

So, after a relative infinite number of rewinds, I have a infinite amount of no clue!

Me: trying to hear the new words that i haven't heard of than typing it into google

I know it's an old post, thought I would chime in still. First let me say I absolutely love this channel. Its absolutely great. Thank you for the excellent topics, the involvement of the community, and the education that you bring. I'm a huge amateur theoretical physicist fan, who just teases my own mind at times. To the topic. We know in thermodynamics, that an energy system cannot be reduced to a zero value. That is to say, the total energy in the universe, is no different today, than after than the most precision measure of time just after the big bang. And the total energy of the universe will remain unchanged throughout time. Energy is constant. Well never add to it, or remove from it. We can all agree on this. However in theory, it would seem, and physics does reflect this, that both space and time are either products of the big bang, or an emergent property. This is interesting to me, as energy seems so exotic in nature, that if you could rewind the universe to " before the big bang" I can make a sound and educated argument, that there was no space or time. In other words, since you cant destroy energy, since it is constant, then it must remain constant, and present, even if there is no space time dimension. In other words, energy can exist outside space time. So I think it's safe to say. That before the big bang there was energy, in a zero time zero space environment. In other words, there must exist an environment, outside space time, not definable by space time terms, yet still a very real environment. Now I'm going to ask questions, and let the universe provide the answers. What does energy do, in zero space,.zero time? To answer that question, we must observe what energy did within space time. One feature, is self organizing systems. The universe is in business of management, and its managing massive levels of energy. If space time was either a product of the big bang, or an emergent property, it still has its roots planted in the energy it came from. Unless u believe that space time is free, and it came at no cost to that original energy the universe started from. That makes no sense in physics, as to say something comes about for free. There must be a cost, to space time. I'm sure some of the universes missing energy, will not completely be found in dark matter, but rather the missing energy lies in a formula, converting energy into space time. Then its constant. So back to my question, what does energy do in zero space, zero time. Observing what it did in space time, it organized into galaxy clusters, star systems, black holes, nebulae, planets, gas clouds etc etc. Let's look deeper. This energy also self organized into life. It self organized into conscious beings. Stay with me please. So let's apply this self organizing feature, for all we know, to zero space , zero time. If , self organization is a property of energy, than energy in zero space zero time, must have also self organized. However, follow me here, it did not have to follow a time line, or spacial restriction. In other words, energy could have self organized into the most complex patterns imaginable, and beyond, instantly in zero time. It would have exhausted its entropy, literally instantaneously, not over a time line. Since were observing this energy, now exposed to a time line, and spacial information, and we know that consciousness emerges somehow, beyond our understanding, then let's assume for a moment, that energy in zero time may have done something similar. That is to say, energy, before the big bang, could have become infinitely complex instantly, and a part of that infinite complexity, would have included consciousness, as it has emerged within space time. In quantum mechanics, making a measurement collapses a wave function. So , I'm imagining, that pre big bang, the energy becomes so complex, infinitely complex, and just as here, consciousness emerges, you cant really say it happened at any specific moment, since time did not exist. ( I realize that for evolutionary systems to occur, there must be time) however, I'm not actually saying that pre big bang, any evolution occurs, I'm saying the energy was already in it's most infinitely complex state, not requiring evolution. Its tough to imagine but stay with me. I mean our minds are not equipped to see outside space time. Our imagination is our best and only tool here let's use it. Soo, that primordial energy before the big bang became self aware, in zero time, observed itself, ( I want to say it made the 1st measurement, but that requires space time so I cant really say that) so don't think in terms of 1st measurement. However, this energy became self aware, observed itself, and collapsed the infinitesimal wave function of itself, giving birth to the 1st particle, the 1st moment of time, and space. A cataclysmic event we call the big bang. Pre big bang all of it is in super position. It was both awake and not, it was both infinity complex, and infinitely disorganized, ( my imagination makes me think, that superposition is actually a zero time zero space state) where all possibilities are observed at once. Its really hard to get your mind around it, u have to think abstractly to even try understanding. After the big bang, the universe wants to assemble itself back into that infinity complex structure it started out as ( cant really say started because that infers time ) so , what I'm saying is pre big bang, the energy was already both infinitely complex, and infinitely disorganized, and both were emergent .that is to say each reality was at play. On our side, after the big bang, its trying to conserve it's own patterns it once ( cant say once that infers time...) but its trying to achieve balance with its self. Except now its exposed to a time line. It must travel this time line to get back where it started. A part of that time line must also include consciousness, since it existed pre big bang as a part of that infinitely complex structure, so in other words you could say it was destined, for consciousness to emerge in our universe, since it was already a part of that structure pre big bang. On the other side, that super positional state of the energy, pre big bang, that was infinitely disorganized, did not collapse it's own wave function, and continues to exist outside space time. There is energy there, but in such a disorganized state, that it remains that way in zero time / space. Both realities exist, but you could say the other does not matter, since nothing arises, emerges, or changes ( I know again changes infers time) , follow me here. I'm saying a part of the cosmos exists outside space time, where there is no evolution. Which contradicts what I'm saying because evolution requires time, which is what our universe did. On one side there is no evolution in zero time, and on another side, there is evolution in time. The universe had to realize both. As, both would make up, in superposition, the energy before the big bang. I think both sides are connected however, each influencing the other, which is were entropy comes to play. Ultimately, I think both universes become one, and balance each other, and they become mirror images. Which raises the question, how does the side infinitely disorganized, never evolving, become a mirror to our own universe? Well, since they are connected, they must share information with each other. The universe of infinite disorder, is sharing its influence with our own, played out in entropy. And our universe, would be sharing information with it, causing new, and organized information to become present, in other words the other universe is experiencing backward time. Our universe will evolve, into the most exotic example of disorder, entropy, and the other universe will go back in time, becoming the most amazing example of order possible. Both in harmony, one becomes the other, the other becomes the one. Both in superposition of each other. When our universe reaches it's most ultimate point of entropy, the other will reach it's most infinitely complex pattern. Which is how it all started. Then they trade places, the cycle happens again. Like an hour glass pouring from one side to the other Consciousness flips the hour glass, but not consciously, by virtue of mechanics. Both universes always connected, in zero time, zero space. In superposition with one another. Its really tough to get my thoughts out on this. My imagination takes me places I cannot put in words, its abstract. As the hour glass analogy, there must be a time when each universe is equal, equal information, space and time, then a transition happens. You would never know it happened, all your information, matter / energy would suddenly exist on the other side, like a clone. Then the other universe would go back to zero time zero space, allowing the other to evolve in space / time, until it goes so far, that it switches sides and repeats its cycle, as the hour glass turns. I've done my best to share my thoughts, please don't be to hard on me. I'm unsure if I've explained it well enough.there is alot i left out. im trying to be as fundamental as i can, i mean were talking about "before big bang" ( which i dont like since before infers time ) , and fundamentally , before the big bang, there must have been energy . so energy is whats fundamental here. not space time, not gravity, which emerges from space time. ive purposely contradicted myself, because this conversation is like a mind experiment. its the only way i know to communicate abstract thought. introducing a self induced conflict really helps my thinking, just as many mental experiments. Schrödinger's cat being one of the best.

I know all about inflation, I remember when I was -67 years old and could buy a coke for 5 cents 😕

What came before the thing we don’t know when, where, why, and refuse to address who and what. This should be good.

I think this is my favorite series so far. Which makes me wonder what happens in Black Holes.

The Big Foreplay. Duh.

my mom said every big bang starts with a big bowl of chili con carne...aőgh... maybe the expansion never had a begining and its only accelerating from our perspective idk im dumb xd

so we may be part of a ever expanding fractal multiverse that be so cool

Could dark energy be some expression of a field similar to the inflaton field?

I find this much easier to grasp than love island.

The fact that anything and nothing had no beginning means parts of us have been through forever to actually form us which makes me stop worrying and happy because these parts know what forever is and they will continue the forever after i die and will create me again no matter what odds are there and i wont even sense the long time taken to do that

He’s so awesome at explaining this

It would be CRAZY if it was the Higgs.

I didn't understand any of this until I hit the bong. Now it all makes sense........man.

So the "multiverse" is like a frothing bottle of cola with a load of bubbles all continuously appearing, colliding and merging or reforming in the liquid?

One minute and 48 seconds in and my head begins to hurt with the information I can’t begin to comprehend

Could the universe bubbles actually collide? Or would the space in between them always grow faster than the space within them?

i probably know more about space and geography than all my friends because i read soooo many articles about black holes, supernovas and stuff i watch these kind of videos about the universe and i love geography. like love it. i love learning about new countries, new animals, and about how some were formed. i love anything space-related. i am just passionated, like my mom:

Do these limitless other universe bubbles share the same physical laws, or is it possible that some of them have different settings on the "dial" you sometimes mention? Asking on behalf of my friend, the Anthropic Principle.

I swear best physics/universe channel EVER! Been watching for like a year now

I hope you know that you will be respected as this generation's Carl Sagan

This is not Science...This is Philosophy

Ok , so not before the big bang then . You know when we read the title , we're not thinking " before a tiny span of time after the initial state ." Thanks for the sophistry .

I think you exist only in this youtube video. And also in Berlin techno clubs. But not outside of these two environments

My mind has just been *blown*

Nice of PBS to make a documentary for particle physicists.

If the inflaton field had a local minimum which by chance reached the actual minimum, who says our current 'minimum' is not actually just a second local minimum/false vacuum? How do we know inflation is completely stopped?

My favorite Australian after Steve Irwin RIP. Both eagerly and earnestly share/d their respective passion. Without reservation however I understood what Steve talked about far more.

Its very simple to me. First ever unit of energy had to be made out of no energy yet we base laws of physics on that being impossible. Lol

As long as you define “pretty good idea” as “NO IDEA” then yeah I would agree with you on that one.

Dodged explaining the origin of the universe. Just talked about expansion after. Explained the bang part. Left out the "Big" part.

Is "sup?" on your t-shirt some weird equation or it's just what's up?

When you ask "What time is it?" and the other person tells you about time and space, big bang, space inflation, string theory...NEVERMIND!!! I'm gonna watch some "Teletubbies" now...

You guys completely made me opsessed about space. Thank you ❤️

Hi Space Time. Just wondering how can the inflation extend to infinity if the inflating regions keep getting smaller. Wouldn't the non inflating bubbles be created up until a point where the regions are smaller than the planck volume?

"Cool story bro" - Matt, 2019

I happened before the video

Always been a hobby astrophysicist and so glad to stumble on this channel. Astronomy and astrophysics are my favorite things in the whole world.

I FEEL SMART

(Somewhat beer-induced) takeaway: Alan Guth's Inflation Theory rests upon his local minimum idea, which he pulled out of his ASSumption.

Me: interesting My brain 20secs in: good night, bro. Wake me up when you go back to funny cat videos

Wrong question. Right question would be: WHY did the Big Bang happened?

Thank you for talking about the speculation and not talking as if it is factual like some proponents.

The answer is simple, God said: "Let there be".

So, if a small enough mass in a small enough space can theoretically spawn infinite universes, what does that mean for the singularity at the centre of a black hole? Maybe it's not infinitely dense so much as it is infinitely expanding within itself, making it "bigger on the inside" from our perspective.

There are a few basic questions about the source of the universe, for example, A. Is the concept of abstract reality rational? B. Could there be different universal rules or laws of physics, many universes (multiverse)? C. Is spacetime finite or infinite? D. Is the source of energy from a quantum field or a cyclic universe? E. And did something “just exist” or was it created? This video, ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Emf6h8KwAdM.html, provides a framework for a logical discussion of these “philosophical” issues. It defines what precedes the big bang in terms of nothing plus four somethings (universal rules, laws of physics, spacetime, and energy). This description provides a reference point for philosophical questions related to the four somethings (8 minute video).