Evidence for Big Bang Cosmology

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  • Опубліковано 15 вер 2024
  • At the beginning of this series, we talked about the Big Bang, which was the beginning of our universe, and what happened in the early epochs thereafter. But what we didn't talk about was how we know all that stuff! What is the evidence that supports this model? There is a lot of it, and we weren't ready to understand it then, but now we are. Let's talk about recession velocities, the cosmic microwave background radiation, the ratio of hydrogen to helium in the universe, and all the other empirical evidence that supports Big Bang cosmology.
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КОМЕНТАРІ • 745

  • @henrydyess9863
    @henrydyess9863 3 роки тому +332

    Came here for the flat earth debunks, stayed for the science videos.

  • @shashikaushal7127
    @shashikaushal7127 5 років тому +539

    I love your intro. Please never change this at any cost. I love it.

    • @somalithinker419
      @somalithinker419 4 роки тому +20

      It's really bit childish, but ok

    • @nebtheweb8885
      @nebtheweb8885 4 роки тому +3

      @@somalithinker419 It is the best national anthem ever! ua-cam.com/video/EDQuuU8wCbo/v-deo.html

    • @MBicknell
      @MBicknell 4 роки тому +31

      @@somalithinker419 you're a bit childish!

    • @grosty2353
      @grosty2353 4 роки тому +5

      Bicknell music what a comeback

    • @grosty2353
      @grosty2353 4 роки тому +11

      I agree tho, it makes me smile every time I listen

  • @thegoodlydragon7452
    @thegoodlydragon7452 3 роки тому +74

    My uncle the other day expressed skepticism in the big bang theory. Explaining evolution to him was easier since an interested layman like myself can grasp the evidence for it, but I had some trouble with the big bang theory and had to admit that I myself didn't fully grasp its basis. After watching this, I see that this is in part because it requires math that's well above my mathematical knowledge, and yet, accepting the premise that the experts have done that math and it checks out, I can otherwise see the very solid reasoning behind it. I sent him this video to give him a more comprehensive explanation than I could.

  • @amungust4054
    @amungust4054 Рік тому +32

    Most videos explain what the big bang was, but explaining the evidence and history of the theory is really powerful.

  • @dug.8523
    @dug.8523 Рік тому +19

    Hey Dave, raised hardcore fundamentalist Christian. I come back to this video every couple months so that I keep it memorized. More than once I have been asked how I could possibly believe in the big bang and I just quote you verbatim hahaha. You are one of the main reasons I was able to escape the doctrine. Thankyou :)

    • @marcekessen8003
      @marcekessen8003 9 місяців тому

      In my head cannon the Big Bang is God creating the universe, otherwise where did the singularity come from? The math breaks down in the first bazillionth of a second after the Big Bang and only works from that fraction of a second forward. I do not feel science and God are mutually exclusive, I think God made a wonderful universe for us to explore and use and to keep our brains( made in His creative image) busy!

    • @bluestriker256
      @bluestriker256 3 місяці тому +2

      ​​@@marcekessen8003that's a fallacy at its finest. All scientific breakthroughs, the amount of work and the brightest minds in mankind to propose and corroborate these observations and you go "God created the singularity that produced the big bang" . Based on what observations or actual facts? Still doing the same thing religion has always done: explaining what we YET do not understand with fairy tales.
      And btw, if a God created the singularity, it must have been the primordial diety of Chaos from Greek mythology since that sounds more badass than loser Jesus Christ. (See how I also made an assumption and assigned it to the creation of the universe?)

  • @RT710.
    @RT710. 5 років тому +38

    I saw you shared your video about the stellar life cycle and it reminded me that I need to catch up on this playlist! I absolutely love your content man!

  • @derfunkhaus
    @derfunkhaus 5 років тому +72

    I wish you would explain just what physicists mean when they talk about two or more fundamental forces being unified or combined. Knowing a little about each force makes it actually harder for me to understand the concept of unification. What does it mean, for example, if gravity and electromagnetism are unified?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  5 років тому +59

      well from the little i understand, we would be talking about a unified quantum field theory which would mean a new particle that would carry that new force, so it would predict a particle, and then i'm sure there would be all kinds of crazy equations. but other than that i'm not sure!

    • @thunder7433
      @thunder7433 3 роки тому +19

      @@ProfessorDaveExplains “from the little I know” has made over 1000 videos about teaching others

    • @501thtrooper4
      @501thtrooper4 3 роки тому +4

      @@thunder7433 Yeah knowing a bit about the subject is like knowing how the youtube algorithm works.

    • @user-nu2it6kf2m
      @user-nu2it6kf2m 2 роки тому +8

      @@thunder7433 Dave is humble

    • @JimmyKlef
      @JimmyKlef 2 роки тому +5

      Felicity Chevalier right, well yea it’s basically all just “math” when you are looking backwards or forward in time and into utterly inhospitable conditions. But there is a lot more than just math equations. From our perspective, we can use math to try to understand and make predictions but as this video made a point of, we verify the math with real world observations. There multiple lines of sight to look through to find reality at these levels, not just math. But yes, the math is extremely complex, mathematicians are almost unfathomably great at what they do and no one should underestimate any scientist by fooling yourself into thinking you have some sort of understanding about their field that they do not. This is their backyard. It’s their baby. It’s the back of their hand. When we listen to something like Beethoven, we don’t challenge his musical knowledge. If there was some sort of musical competition, and there was someone who merely has listened to music, and then Beethoven himself… we would all bet Beethoven is going to win absolutely whatever it is. Because his level of understanding is so far beyond people who haven’t delved completely into music right? It’s absurd anyone would think differently of any expert, really. Especially when we can see the great fruits of their labor pay off enormously in innumerable ways. Just like we can hear that Beethoven is phenomenal, we can apply that here too. Science isn’t dogmatic within itself, but those who argue about “scientism” don’t understand the difference between a lay-person understanding they are not an expert and trusting the work of experts, especially when holding a phone in your hand made by the science and math of this world you couldn’t make in a million years… we still never not have the ability to check. Where any religion is constantly scrambling and editing itself to cling to existence. Of course challenging religion is frowned upon. That’s because it requires dogma to remain in a world where science is constantly proving it wrong. The bible, nor any holy book ever, let alone “constantly” disproves anything. If you really think scientists are not right, you can step up and prove them wrong if you start learning and running good experiments yourself. But if nobody has a better explanation for something, it’s because it isn’t a better explanation. At least not yet. Not until it can meet and surpass whatever criteria previous theories before it can.

  • @hetdave8679
    @hetdave8679 5 років тому +173

    u are underrated

    • @sandeepsingh-uc9oo
      @sandeepsingh-uc9oo 5 років тому +17

      Teaching is always underrated on UA-cam

    • @ds525252
      @ds525252 4 роки тому +1

      Deservedly so.

    • @gwh0
      @gwh0 4 роки тому

      @u little shit Dave here is a chemist. I doubt he understands the topic he's talking about. I've studied it in detail and I *know* I don't.

    • @lauramoreno8742
      @lauramoreno8742 4 роки тому +5

      gwh0 wtf, he as an MA in science/chemistry from Cal State Northridge and he has taught physics, science chemistry and mathematics in high school. So what u said doesn’t make sense

  • @constpegasus
    @constpegasus 5 років тому +45

    Thank you for this video Professor Dave. You do an incredible job of explaining topics.

  • @andrewstoll4548
    @andrewstoll4548 4 роки тому +81

    Am I wrong to get sad watching this video and there is a thumbnail for a flat earth discussion below it.

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  4 роки тому +68

      I do flat earth debunks, so that's probably a factor.

    • @andrewstoll4548
      @andrewstoll4548 4 роки тому +4

      @James M please tell us where he is wrong... I'll wait.

    • @andrewstoll4548
      @andrewstoll4548 4 роки тому +10

      James I never said anything about Professor Dave being wrong.

    • @b4byf4c3455451n
      @b4byf4c3455451n 4 роки тому +2

      @@ProfessorDaveExplains How about the new hypothesis of the big bang constantly happening in the infinitely small world ..?
      To Planck magnitudes

    • @JerseyLynne
      @JerseyLynne 3 роки тому +2

      @@b4byf4c3455451n never heard of it

  • @daveh9521
    @daveh9521 4 роки тому +8

    Some really great explanations here; worth several views. You're an excellent teacher Dave!

  • @timemachine13
    @timemachine13 4 роки тому +15

    Thank you Professor Dave for the informative well put together video.

  • @donvanduzen8944
    @donvanduzen8944 4 роки тому +35

    Earth goes around the sun. Funny.
    In all seriousness, good concise synopsis for us laymen. Should be compulsory viewing for all creationists and Flerfers.

  • @gdaytoyamates8391
    @gdaytoyamates8391 Рік тому +1

    I love how you say "cosmic microwave background". you always emphasize it, and it just makes me happy for some reason

  • @serendipitousillicit734
    @serendipitousillicit734 5 років тому +100

    Start of the universe be like:
    Bang

    • @Bilbus7
      @Bilbus7 5 років тому +5

      It's sad that you had to edit that...

    • @stephenbonutto2713
      @stephenbonutto2713 5 років тому +24

      @@Bilbus7 Its sad that you say its sad he had to edit that

    • @Soupy_loopy
      @Soupy_loopy 5 років тому +5

      Misnomer. Big Bang was incredibly small and very quiet.

    • @Bilbus7
      @Bilbus7 5 років тому

      @@stephenbonutto2713 You're neither funny nor clever.

    • @stephenbonutto2713
      @stephenbonutto2713 5 років тому +17

      @@Bilbus7 We've got one salty sailor !

  • @PrettyLittle_Piss
    @PrettyLittle_Piss 3 роки тому +2

    People talk about "putting work" into their channels... Bruh, you more than deserve your 1.4 million subscribers.

  • @NeverlandSystemPunkGirlChloe

    I LOVE how you explain things so well, so clearly... and without like making audiences not familiar with science and advanced science feel dumb or lost. You are so great at this!

  • @giovanni-cx5fb
    @giovanni-cx5fb 3 роки тому +5

    Great video. One correction, though: the Einstein quote about the cosmological constant being his "biggest blunder" is actually a rumour started by Gamow, who was widely known in the physics community for making stuff up.

  • @blowmanuts9584
    @blowmanuts9584 2 роки тому +4

    How insane is this. The fact that it has this amount of evidence going for it makes it crazier, I love it. A lot of work, math and a little bit of luck and we get the most interesting theory of the universe we've ever had.

  • @vinamraparashar7590
    @vinamraparashar7590 5 років тому +22

    Empiricism at it's finest

  • @kevinnazario1015
    @kevinnazario1015 3 роки тому +4

    This is just way too cool!!!!!! Great explanation👍👍👍

  • @mayanksolanki7028
    @mayanksolanki7028 3 роки тому +3

    Please never change your intro, It makes me motivate to learn things. 😁😅

  • @thefrustratedboyy
    @thefrustratedboyy 4 роки тому +2

    Wow one of the most well researched and amazingly explained videos ever🔥👍 great work

  • @MrJoeyWheeler
    @MrJoeyWheeler 4 роки тому +18

    Question!
    What kind of things does learning the nature of the "first force" so to speak (the thing connecting all four current forces) allow us to do? Or is it impossible to tell without knowing?
    Also, if the waves that make up the Cosmic Microwave Background Radiation became microwaves over time, does that mean that, given a long enough period of time (likely more than humans will exist for), they would become Cosmic Radio Background Radiation waves?

  • @Killbayne
    @Killbayne Рік тому +4

    8:14 Twitter has ruined me and I cant read that line with a straight face anymore

  • @melsop54
    @melsop54 Рік тому +3

    This is fascinating as a Christian, because most of us simply ignore this information. But if I am to believe that God is responsible for this universe and all it's laws...I'd be ignorant to deny the very laws he created and what they seem to indicate. I've come to accept the age of the universe and it's beginning according to this video. I think where we all, regardless of our positions, begin to assume things is at the singularity that was once everything in this universe. If the universe does have a finite beginning, and a finite size, then it stands to reason that that singularity had a beginning. We can assume it does, or it doesn't and has always exploded, expanded, and contracted...but ultimately (in the absence of evidence of things prior to the big bang) we are making assumptions. If we are to accept it did have a beginning, then we must posture the existence of a beginner. Be it God or an alternate universe this one is contained within. With the alternate universe idea though, we'd have to assume that Russian doll of sorts can go on forever and ever...which would contrast with a finite universe. At any rate, I can say as a Christian, I have become able to reconcile my faith and Science in pretty huge ways. The more I learn, the more I see it actually doesn't effect the reality of my faith personally.

  • @Sama-zd4nb
    @Sama-zd4nb 4 роки тому +2

    very very nice and accurate explanation of development of cosmology models. Many Thanks.

  • @Drums-ve8on
    @Drums-ve8on 3 роки тому +24

    Gee all this sciencey stuff must be very difficult to accept for those who think some magical guy in the sky created everything in 7 days.

    • @WhiteWolf-lm7gj
      @WhiteWolf-lm7gj 3 роки тому

      Dude, chill. Being religious does not prevent you from understanding science.

    • @Pigeon249
      @Pigeon249 3 роки тому +8

      @@WhiteWolf-lm7gj Ehhh i disagree. For example young earth creationists (idiots) won't accept most science because it disproves their beliefs.

    • @WhiteWolf-lm7gj
      @WhiteWolf-lm7gj 3 роки тому +6

      @@Pigeon249 I mean yeah, there are some groups like flat earthers and evangelicals who ignore science, but it's not as though the only two options are religious or scientific, there are plenty of religious scientists

    • @jsihavealotofplaylists
      @jsihavealotofplaylists 3 роки тому +3

      @@Pigeon249 Genesis 1:1 is basically the big bang for some, and Genesis 2:7 is a biblical way to believe in evolution. And then its free interpretation and cherry picking time!

    • @hexamethylenediamine7934
      @hexamethylenediamine7934 3 роки тому

      @@Pigeon249 I disagree that young earth creationists or religious people won't accept a lot of science since Georges Lemaître, the person who made the theory of the Big Bang (horrible name), was a catholic priest.

  • @psihostrumpf6233
    @psihostrumpf6233 3 роки тому +5

    Since everyone is asking what happened before big bang i feel pressure to tell you all the truth... i told her that i need her to help me with something upstairs, which of course was a lie. She saw right through me but came anyway... the bang was a big one, but i swear that nothing expanded, what's the fuss all about? By the way - cool video as always, Professor! You rock!

  • @tomctutor
    @tomctutor 4 роки тому +3

    Thanks Dave, big-bang what actually caused/causing this phenomena, not an explosion but something to do with fabric of space time?

  • @tattooryry6859
    @tattooryry6859 4 роки тому +4

    You're awesome Dave!

  • @josephnardone1250
    @josephnardone1250 5 років тому +7

    The discovery of the CMBR was done at the Bell Labs in Holmdel, NJ. As a N. Jerseyite, wanted to point that out.

    • @NoName-fc3xe
      @NoName-fc3xe 5 років тому +1

      It's good to know that NJ brought us more than Snookie and the Situation.

  • @lore.keeper
    @lore.keeper Рік тому

    Can't thank you enough Dave for all this effort in preserving and spreading our human scientific knowledge for generations to come. Yours is a most noble cause sir! :)

  • @NeverlandSystemPunkGirlChloe
    @NeverlandSystemPunkGirlChloe Рік тому +1

    I think Einstein's genius is, amazingly, underappreciated. That we STILL see so much of his thinking proven or partially proven right after sooooooo long and so much to look into it... just incredible.

  • @maudlive5337
    @maudlive5337 3 роки тому +2

    i had to watch this for school and i think imma gonna subscribe this was very interesting lol

  • @sarttfft
    @sarttfft 4 роки тому +2

    Sir, You made a small mistake, it was not Hubble who discovered expanding of universe. It was Georges Lemaître. He discovered the expanding universe in 1931 and he got noble prize for expanding universe.

    • @c0rtikoZteroids1
      @c0rtikoZteroids1 4 роки тому +1

      Nobel, not Noble

    • @j.k.6865
      @j.k.6865 3 роки тому +3

      Wasn't Lemaitre the one who proposed the theory, but Hubble who discovered the expansion?

  • @Montesama314
    @Montesama314 2 роки тому +2

    "DAMMIT, I can't seem to figure out the nature of the expanding universe!"
    "Did you get rid of the pigeons?"

  • @agusmolfino
    @agusmolfino 4 роки тому +1

    Dave! I'd love to see a video of you explaining the James Webb Telescope implications for cosmology.

  • @YaHomieRen
    @YaHomieRen 4 роки тому +1

    Thanks this will help with my online science class

  • @tejasgreen1717
    @tejasgreen1717 3 роки тому +7

    yeah but Jeebus thought to himself, “13.8 billion years from now, I’m gonna sacrifice myself to myself to save these creatures i’ll eventually get around to creating from myself. Damn, what a great plan I have there!”

    • @DuckInGameStop
      @DuckInGameStop 3 роки тому +3

      I read recently "god sent himself down to earth to sacrifice himself to himself to create a loophole in the rules he himself created" lmao
      basically, why did he need to make himself a physical body, use it to go around doing some magic tricks for random people and telling them their laws were wrong, and then let that body be tortured and killed, just to make it possible for innocent people to not be sent to an afterlife of eternal torture (but only if they worship him constantly, of course!)

  • @olxzender
    @olxzender 11 місяців тому +1

    Please make video about how the CMBR was measured

  • @kylemaritz4673
    @kylemaritz4673 3 роки тому +1

    this video is just what i was looking for, thanks a million!

  • @ngonzalesiii
    @ngonzalesiii 2 роки тому +1

    Sir Dave, Professor, what do you think of these scenarios I'm going to mention? Is it possible that how particles come into and out of existence push space time in all directions creating energy and waves? Sort of like how seafloor displacement creates tidal waves? And maybe particles travel to and from dimensions? Popping up in each? And entropy occurring when majority of the particles slow down and then stop coming into existence on either dimension? This is probably dogcrap, but fun for me to ponder. What do you think? Do waves travel in all directions or just radiate from a single originating point in one direction? Please let me know what you think

  • @D1M8OCreepyPasta
    @D1M8OCreepyPasta 3 роки тому +1

    Have a question, I just want say that I’m not amazing at physics just a fan. I am a data analyst by trade and had a thought experiment that I hope you could give me your thoughts on. I will go very high level for length of comment. For the thought experiment imagine that pre Big Bang there was a void that is 100% filled with subatomic fluctuations between 1 and 0 (everything simultaneously 1 & 0) imagine that there is data probability that inuf simultaneously fluctuations directly next to each othe fluctuate to 1 simultaneously) by adjusting the volume of the wave need to fluctuate to 1 we can create the probability needed to explain the reason why this has not happened again since the universe has been created. At the flash point of inuf random fluctuations aligning. The fluctions became strong inuf to become the Higgs field and first matter was created. This then repelled the equally distributed void fluctuations away from the point of initial matter creation and filling the bubble left behind with the expanding Higgs field and matter. I didn’t know if a similar model was out there and what it was called? Hope you read this apologise for long question.

  • @paulward8087
    @paulward8087 4 роки тому +2

    Am I right in understanding that science usually refers to "the universe" as the "observable universe" ... The key point to make here is that the observable universe is what we think got created by a "big bang event" of which there could be many happening even today in far off regions of the universe.
    So we end up with a potential for a cycle of ...
    Bang > expansion > contraction > repeat
    ... Throughout the entire "universe".
    Another thing that confuses me is at the standard model level what differentiates an elementary partical from from a force or wave ... Just like how the photon was at one point believed to be potentially a wave and not a partical.
    Could all mass / elementary particals be a side effect of their component parts (e.g. some sort of quantum field set)?

    • @williamcacilhas885
      @williamcacilhas885 4 роки тому

      Paul Ward When scientist speak of the observable universe, they are talking about the things we can observe. Let me explain. The universe is expanding at an accelerating rate. From an observer objects further out will appear to be moving faster than those closer. However, objects past a certain point will be in an area of the universe expanding faster than the speed of light. Their light is incapable of reaching us. So the “observable universe” is referring to the sphere of the universe around us that we can still see (where the expansion is slower than the speed of light). Hope that answers your question.
      To answer your other inquiry about the standard model, you have a misunderstanding of the model. There are no particles. There are no waves. There are things that have particle-like or wave-like behaviour. In the standard model ‘particles’ don’t have a definite position, but instead a probabilistic one. You can describe the particle as a wave function which tells you the probability of finding it over there, or over there. Before wave function collapse the particle will have wave-like behaviour. To get particle-like behaviour you have to collapse the wave function. Essentially you measure the particle giving it a more definite position (it’s still not %100 definite).
      So depending on the conditions quantum objects can be described as a wave or a particle, they have a wave-particle duality (this does not make them both a wave or a particle). This is quantum mechanics so I may have something wrong here.

    • @paulward8087
      @paulward8087 4 роки тому

      ​@@williamcacilhas885 In short - you agreed with me confirming: "the universe" is always a reference to "the observable universe" in scientific discussion.
      Observable being big or small, stuff within our roughly 14 billion light year sphere from here due to limitations in technology + laws of physics which it's safe to say is "less and less stuff every day" if the big bang is considered a fact.
      Interestingly though, if we found far out waves of a conflicting nature in spacetime / gravitational constant values then we could potentially confirm the existence of more than one big bang event in regions beyond the observable universe (assuming those big bang events occurred close enough to affect our observable universe)
      The problem with quantum physics as I understand it is that we don't know how to directly observe things smaller than an electron since doing so involves taking a signal or particle stream that bounced off those things and doing so puts you in that Schroedinger place of "is it or isn't it" due to the observation impacting the thing you're observing.
      The description / representation of something and the fact are often different to help simplify the explanation is literally how we can "sum up this problem".
      I tweeted a question to Brian Cox on this "quantum problem of definition of state" ... I proposed that physical matter at a sub quantum level wasn't a thing at all and that could we be potentially looking for some unified theory of waves that at the macro scale can be observed to be behaving as what we call "mass".
      If that's true .. the standard model could potentially be reduced to a single wave form that literally represents spacetime interacting with itself and probability.
      Observing that will be tricky though.

    • @paulward8087
      @paulward8087 4 роки тому

      I'd love to get Daves view on this.

    • @williamcacilhas885
      @williamcacilhas885 4 роки тому +2

      Paul Ward no. When scientist say “the universe” they are referring to the whole. If they’re talking about the observable universe they will generally say “the observable universe.” At least I’ve never heard a scientist not make the distinction before. It is possible to talk about the universe as a whole, including the parts you haven’t seen. You just can’t make too many claims about what’s there.
      There’s not many things smaller than an electron. That Schrödinger property you were talking about is called superposition. Superposition is represented as a wave function.
      However, the not being able to know a particles position accurately nor it’s momentum and the more accurately we know one the less accurately we know the other, is Heisenbergs uncertainty principle.
      None of those are actually limited to subatomic particles. Both of them hold, up to fairly large objects. Significantly large molecules even.
      We can already describe mass. It comes from the sum of the PE (potential energy) and KE (kinetic energy) of a particle at rest as well as it’s interaction with the Higgs field (which I’m pretty sure is just more potential energy).
      For instance an electron all by itself traveling through space, would travel at the speed of light. Except that it interacts with the Higgs Field slowing it down.

    • @paulward8087
      @paulward8087 4 роки тому

      @@williamcacilhas885 A smarter person than me once said "if you think you understand quantum you definitely don't" ... your need to constantly explain this stuff confuses me since i'm not asking how it works, I probably know as much as you do on this subject.
      Superposition and entanglement come up a lot in my line of work. I referenced Schrödinger not because of the uncertainty but because of the impact of "opening the box" or in this case "observing the thing" making it unclear if it really was how it was observed or if that was just a side effect of the observation.
      Heisenberg isn't relevant to the point I was making since that talks about the uncertainty of state in general ... this is why flat earthers exist.
      This constant need to drift from concept / point to concept / point.
      You're making a blanket statement about "the universe" where i believe context is important.
      My original statement was in reference to the contents of the big bang stuff that surrounds us, much of which we can no longer see because it's beyond out observable range.
      When scientists talk about "the universe" generally, they talk about "generally" based on what we can observe what we have deduced.
      My Original question was really ... Does the term "universe" refer to the area we are looking at now around the big bang event we theorise to be the source of that stuff or in the context of Daves presentation are we saying the WHOLE universe came from that one event?
      My thinking is that we don't have enough information to make a call on that either way, so pretty much any discussion about "the universe" is always talking about a subset of stuff from the bang bang "the observable universe" as we have no way of determining anything beyond that.
      One way to think about this is to make statements like ... "Given two big bang events we cannot be sure what impact they might have on each other or at what proximity they would need to be have such effects" ... nor could we know if it's even possible for there to be more than one big bang ever.
      This is much the same as Daves point about "if we lived say a million years from now in this exact universe, we might agree with flerfs that the universe was indeed made just for us" as there would be much less in the night sky, and we would have way less information that a big bang ever took place.
      We can only determine our "theories" from what appears to hold true in the complete set of data we have.

  • @erichvombunkers6226
    @erichvombunkers6226 4 роки тому +2

    Thank you so much for this knowledge

  • @Montesama314
    @Montesama314 2 роки тому +1

    Ah, I think I get why steady state theory wouldn't line up with the existence of background radiation: if there was indeed some C-field generating matter, then the background radiation would have differing frequencies depending on where new matter manifested. From my understanding, the frequency would be higher in places where matter had just or is being formed, with lower frequencies where the matter has cooled down and moved across the universe. You might have little creation "ovens" where background radiation is highest.

  • @firegreat3420
    @firegreat3420 6 місяців тому +1

    But why should the night sky be very bright even if the universe was infinite with infinite amount of stars?
    The sum 1 + 1/2 + 1/4 + 1/8 + ... is finite and equal to 2, but there are infinite number of terms.
    If the universe has infinite amount of stars, that would not mean that the night sky would be bright as a day, and nor would it mean that any particular object in the universe would experience an infinite force of attraction from an infinite amount of objects with mass.

    • @logickedmazimoon6001
      @logickedmazimoon6001 6 місяців тому +1

      The stars aren't tightly clustered together. The nearest neighbor to a single star is usually light years away. You also have to take into account the other celestial objects that either block or absorb light like dark energy and black holes. Beyond the observable universe, everything may as well be infinite for all we know, there could be a gigantic light wave about to descend into the observable universe but by definition we can't observe or test what is unobservable. your sum you describe actually illustrates this about what we mean by infinity, meaning that we can walk through all the sums individually but that doesn't stop us from seeing that it's approaching 2 so we can safely say that the answer is 2 when it comes to reality.

    • @petroleumalley
      @petroleumalley 4 місяці тому +1

      Check Olbers's paradox.

    • @logickedmazimoon6001
      @logickedmazimoon6001 4 місяці тому

      @@petroleumalley Interesting! So essentially we'd only expect uniform brightness in a steady state universe

  • @danjohnston3395
    @danjohnston3395 3 роки тому +2

    I freaking love Professor Dave. Teaches in a way that is very relatable and covers the big points. I always turn to Dave when flerthers start clogging up my fb page with their ill-informed bullshit. Thanks Dave!

  • @solaris4022
    @solaris4022 3 роки тому +1

    Love watching the videos then coming to the comments, that way you get to see Dave teach in a way layman can understand and then kick the ass of everyone who's completely incorrect in a way that just screams: 'Good for you, you're wrong'.

  • @eljison
    @eljison 2 роки тому +1

    Great job on this.

  • @JohnDerhammer
    @JohnDerhammer Місяць тому

    It depends on whether you ascribe yourself to d-brane or n-brane theories and then whether there were originally 9 or 13 primordial dimensions. Quantum Gravity may play out to provide a better way of explaining such concepts as gravitrons and maybe further expand on the neutrinos and their role in predicting stellar collapse.

  • @hadavisjr
    @hadavisjr Рік тому +2

    How do you now reconcile this position with the latest JW telescope imagery calling this understanding into doubt?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  Рік тому +14

      Easy, that's not a real thing. It's a lie on the internet. I made a debunk about it: ua-cam.com/video/-S-mg1LMOAo/v-deo.html

    • @hadavisjr
      @hadavisjr Рік тому +5

      @@ProfessorDaveExplains Thx, I’ll check it out.

  • @jorgecorea7528
    @jorgecorea7528 Рік тому +2

    Never expected to see Edgar Allan Poe on a Physics video

  • @johnnydeformed7123
    @johnnydeformed7123 4 роки тому +3

    You're good at explaining things. Is that why you named your channel that?🤔

    • @leekfam7667
      @leekfam7667 4 роки тому

      Read the about section of the channel I think there’s something about that there

  • @techhelp1941
    @techhelp1941 4 роки тому +2

    Dear Dave I have a question, If universe is continously expanding with an acceleratory rate and everything is in non inertial frame of reference then inertial frame of reference does make any sense?

    • @stanrogers5613
      @stanrogers5613 4 роки тому +3

      That would be a problem if the _stuff_ in the universe was accelerating, but on the scale of universal expansion, it's not. It's basically doing "local" stuff - staying still, or at least staying within an inertial reference frame, or accelerating in normal ways that we can understand - while space itself is expanding at an accelerating rate. I know it's hard to wrap your head around it, but galaxy clusters aren't moving away from one another, they're just getting further apart. Extra distance is being inserted between them. They're staying in the same place while other places to put places are added between them. Yes, that's as weird as it sounds. That's *not* how things work in the world we _know_ how to think about, so we need to spend time learning how to think about it.

  • @charlieangkor8649
    @charlieangkor8649 4 роки тому +1

    Microwave background explained: you make a big bonfire, then a photographer takes a firefighter suit and steps into the middle of a big flame. Then he takes few pics. They will show just uniform bright orange flame color because he is photographing the flame from the inside.

  • @MBicknell
    @MBicknell 4 роки тому +5

    Oceans... Dont have wings

    • @DuckInGameStop
      @DuckInGameStop 3 роки тому

      That means absolutely nothing, thanks for wasting everyone's time.

    • @anokiyoussou
      @anokiyoussou 3 роки тому +1

      @@DuckInGameStop That is a reference to Professor Dave says "OCEAN...DON'T HAVE WINGS!" to Flat Earthers.

    • @DuckInGameStop
      @DuckInGameStop 3 роки тому

      @@anokiyoussou oh, okay

  • @adviksharma2072
    @adviksharma2072 3 роки тому +1

    u deserve more views

  • @vilebeggar622
    @vilebeggar622 3 місяці тому +1

    The goat of science

  • @alexeifando747
    @alexeifando747 3 роки тому +3

    Dave is gangsta!

  • @bartonpaullevenson3427
    @bartonpaullevenson3427 3 роки тому

    I thought Poe's argument was that the Universe wasn't infinitely old, and therefore even if it were infinite in size and filled with stars, most of the starlight wouldn't have had time to get to us. What did he actually say?

  • @riffshyperion
    @riffshyperion 4 роки тому +1

    Hihi, nice, I wanna see you build a bubble chamber around the LHC and take pictures of the collisions :D But it carries the message, so fine with me.

    • @freddan6fly
      @freddan6fly 4 роки тому

      The LHC detectors are electronic bubble chamers, so that is how LHC works. I think Physics Girl explained it in one of the videos where she visits Cern.

    • @riffshyperion
      @riffshyperion 4 роки тому +1

      @@freddan6fly I work on one of the detectors and while bubble chambers serve the same purpose these detectors are enormously more complicated than that. So it's both a cute comparison to carry the idea of how they work and a huge oversimplification. The collisions recorded by bubble chambers were photographed and interpreted by measuring the tracks by hand. Nowadays this is done by supercomputers and no one has ever seen an LHC proton proton collision with their own eyes; all we have are reconstructed images like this Higgs event candidate: cds.cern.ch/images/ATLAS-PHO-COLLAB-2012-011-1/file?size=large

    • @freddan6fly
      @freddan6fly 4 роки тому

      @@riffshyperion I know it is an enormous simplification, yet I can get a hint of an idea of how LHC works. I am just MsEE not working with physics but product development r&d, still interested in physics.

    • @giovanni-cx5fb
      @giovanni-cx5fb 3 роки тому

      I scrolled down the comments to see if someone else had noted that, I'm glad you did.

  • @G0lden07
    @G0lden07 3 роки тому +2

    Hey professor Dave do you still reply? I have a question. Einstein's theory of general relativity says there is no gravitational force but rather it's just the warping of spacetime. If that's true then why did you include the gravitational force into the model? Shouldn't they be only the 3 forces?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  3 роки тому +15

      It's still an apparent force, and if we find the graviton and make a quantum field theory for it it'll be considered a force in the same sense of the other forces as well. At least that's my understanding.

    • @G0lden07
      @G0lden07 3 роки тому +3

      @@ProfessorDaveExplains Thx for your answer I appreciate it :)

    • @DuckInGameStop
      @DuckInGameStop 3 роки тому

      I thought gravitational force was caused by the warping of spacetime, I didn't realize they were two conflicting ideas... I guess that makes sense though.

    • @G0lden07
      @G0lden07 3 роки тому

      @@DuckInGameStop the curvature of spacetime means that your future points towards the planet and that's what causes you to fall giving you the effect of a force but it isn't actually a force since nothing is actually pushing you towards the earth it's just you moving in time.

    • @DuckInGameStop
      @DuckInGameStop 3 роки тому

      @@G0lden07 oooh, interesting
      but if the curvature of space creates the effect of gravity, pulling things toward large objects, what does the curvature of time result in? I wonder if there are theories about that...

  • @Daniel_Thotumpuri
    @Daniel_Thotumpuri 3 роки тому +1

    Great stuff! Thanks

  • @FenrizNNN
    @FenrizNNN 2 роки тому +4

    Do you think the particles get nostalgia when they're transformed into energy?

    • @drsatan7554
      @drsatan7554 2 роки тому

      No

    • @LiLUndred
      @LiLUndred 2 роки тому

      @@drsatan7554 "Ah, this reminds me of the good ol' bang" said the up-quark

  • @mrcat5508
    @mrcat5508 Рік тому +2

    But the important thing we need to know is what shape the earth is

    • @adryanclay
      @adryanclay 7 місяців тому +1

      Its like a very big ball, like, REALLY BIG, around 12 kilometers in diameter. Its pretty thick if i do say so.

  • @richtaylor6039
    @richtaylor6039 4 роки тому +1

    Excellent vid!

  • @Playboyy1985
    @Playboyy1985 4 роки тому +1

    Might be a dumb question but why doesn’t gravity stop or at least slow down expansion in the universe ?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  4 роки тому +4

      So the expansion is actually accelerating, and we have named the unknown cause of this phenomenon "dark energy". Nobody knows why quite yet!

    • @G0lden07
      @G0lden07 3 роки тому

      @@ProfessorDaveExplains What about virtual particles they keep poping in and out of existance shouldn't that expand the universe? We are also expanding time since space is not infinite time shouldn't be infinite either yet time goes on, doesn't that mean that we are expanding time and with that expansion space does too? Why does no one talk about that yet they believe dark energy doesn't this make more sence?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  3 роки тому +1

      I don't really see how quantum fluctuation would impact expansion, nor what "expanding time" could possibly mean. But perhaps a physicist would beg to differ.

    • @tiedeman39
      @tiedeman39 2 роки тому

      Also, before the "discovery" of dark energy, it was believed that it would slow down and recompact down to a "Big Crunch", with everything becoming another singularity

  • @simonlambeth666
    @simonlambeth666 4 роки тому

    Excellent presentation!

  • @MrFree006
    @MrFree006 4 роки тому +2

    Can the Cosmic Microwave Background Radiation be converted into electricity to power our houses?

    • @MenacingPerson
      @MenacingPerson 3 роки тому

      sure, but only a little.

    • @paulmahoney7619
      @paulmahoney7619 3 роки тому

      In theory yes, but it would be more efficient to try and use starlight as a power source.

  • @StaticBlaster
    @StaticBlaster 2 роки тому +2

    Some people including scientists might inadvertently use the word "created" when talking about the origin of the universe. Creation implies some kind of work was involved whether it be nonsensical supernatural forms of work i.e., a god, or work through natural means. It's possible the universe was "created" in a naturalistic sense however more often than not nature seeks the path of least resistance. So, I think it's more accurate to say the universe is an inevitable natural consequence of some deeper laws. In fact, space and time themselves might not be fundamental. That's what Brian Cox has said, and I definitely agree.

  • @flatisland
    @flatisland 4 роки тому +3

    9:46 could creating similar conditions as in the Big Bang initiate another Big Bang? I mean if so, that would be dangerous, no?

    • @rebeccacummings6697
      @rebeccacummings6697 3 роки тому

      no, it wouldn't create another big bang

    • @flatisland
      @flatisland 3 роки тому

      @@rebeccacummings6697 why not?

    • @rebeccacummings6697
      @rebeccacummings6697 3 роки тому

      @@flatisland because the conditions during the big bang didn't create the big bang so recreating the conditions during the big bang won't create another big bang.

    • @flatisland
      @flatisland 3 роки тому

      @@rebeccacummings6697 we don't know for sure what initiated it or if it even happened, so we don't know for sure what happens if we create collisions with higher and higher energies. All they do is smash particles and hope to prove some theories right or wrong without actually knowing what exactly will happen. Trial and error. I.e. it's not a demonstration, it's an experiment. And I think tampering with forces we don't exactly know what they are is a little risky. Recent example: dark matter. For decades physicists were sure it exists, now a new study is out that might turn things around.

    • @rebeccacummings6697
      @rebeccacummings6697 3 роки тому

      @@flatisland ok, I see what you're saying

  • @zipplade
    @zipplade 4 роки тому +5

    You must be wrong because I do not understand it. (Mr. Kent "Logic")

  • @couldntcareless7884
    @couldntcareless7884 3 роки тому

    8:42 that needs further explanation, I think, because the universe expands at accelerated rate, which makes the actual distance to the farthest galaxy about 30 billion light years

    • @didierleonard7125
      @didierleonard7125 Рік тому

      Our observable universe is a sphere of 45 billions light years radius as per today date…

  • @linme4330
    @linme4330 3 роки тому +1

    I enjoy watching you debunk all the hoax in the comments just a little too much. Love ur videos also

  • @gamingllama7464
    @gamingllama7464 4 роки тому +7

    god dammit I love science so much

  • @sayadiyeojhenries.815
    @sayadiyeojhenries.815 3 роки тому +10

    Yet some delusional people thinks that the universe is made by some god in a week

    • @sofiana580
      @sofiana580 3 роки тому +1

      the Big Bang theory says nothing about why/if or who made it and if you are not stupid u know u can believe in some god(maybe not the bibles god) and science at the same time. You know...god could have created it in exactly the described manner. Don't know why religious ppl don't say that always. Use the hard work of others to confirm their own believe, seems like a logical thing to do

  • @haroldbeaumont2887
    @haroldbeaumont2887 4 роки тому

    ITS HOW AND WHERE WE OBSERVE THE UNIVERSE , ITS SO INFINITE THAT ITS SO PUZZLING .

  • @two_x_4386
    @two_x_4386 4 роки тому

    One Question. Why don't all the galaxies spin in the same direction from the big bang? They should, righ fom the point of a explosion?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  4 роки тому +6

      Galaxies did not form in the initial event. They didn't form for millions of years. Start this astronomy playlist from the beginning if you want to understand the structure of the universe.

  • @nuurshewiilqaran4266
    @nuurshewiilqaran4266 5 років тому +1

    Prof.Dave please talk about a topic covering all the concepts of Genetics. I know you talk most about chemistry but plz

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  5 років тому +6

      I talk about a wide variety of subjects, including genetics. Maybe snoop around my channel a bit so that you are more aware of what I have already done.

    • @zitt4147
      @zitt4147 5 років тому +2

      @@ProfessorDaveExplains How did you manage to learn all of the things you explain to us while being young? As videos show, you deeply understand the topics you are talking on as you can explain them to the viewers. How many hours did it even take?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  5 років тому +4

      well i studied chemistry and biochemistry and physics in school, the rest is just me reading on my own. my knowledge is not especially deep, but it's fairly broad, so that lets me learn new subjects quickly.

    • @zitt4147
      @zitt4147 5 років тому +2

      @@ProfessorDaveExplains I was stunned upon seeing you talking about RNA transcription and neurophysiology and about The Big Bang theory right after that. Keep up the good work, subscribed as soon as I came across the first vid

  • @rebeccacummings6697
    @rebeccacummings6697 3 роки тому

    is it a possibility that if some things went differently, the electromagnetic force could've split into the electric and magnetic force?

    • @G0lden07
      @G0lden07 3 роки тому +2

      No that's not possible since magnetism can't exist without a moving electric charge. Electricity can function as a force of it's own but magnetism certainly doesn't so I'm not sure if this is possible.

  • @simon2636
    @simon2636 4 роки тому +2

    I find it ironic that nowadays the Big Bang model is presented as a refutation of the "creation myth" - although back in the day when it was first proposed (by Georges Lemaître - a catholic priest), it was accused by the scientific community of being "too religious" - by requiring the Universe to have a Cause beyond time and space :D

    • @JonCrs10
      @JonCrs10 3 роки тому +1

      Or more aptly, don't treat science like religion or religion like science.

  • @aaron2891
    @aaron2891 Рік тому +1

    Is it just me, or does the Electroweak Model of the Early Universe look an awful lot like a cladogram?

    • @adryanclay
      @adryanclay 7 місяців тому

      "Looks like" doesn't mean it is

  • @bogosbinted3146
    @bogosbinted3146 2 роки тому +3

    "Actually, the earth doesn't go around the sun. That is a strawman. You are dumb. THAT IS AD HOMINEM. Dave, stop adhomining!" - Every Flat Earther Ever

  • @rynx4708
    @rynx4708 2 роки тому

    2:47 Shouldn't That Be Stars Instead Of Galaxies Since The Idea Of Galaxies Did Not Crop Up At That Time Before Hubble Made His Discovery

    • @eljison
      @eljison 2 роки тому

      No. The idea that there were other galaxies "cropped up" earlier. The "Great Debate" between Harlowe Shapley and Heber Curtis took place on April 20, 1920. Hubble discovered that the distances to Cepheid variable stars in Andromeda resolved the question of whether "spiral nebulae" were part of the Milky Way in 1923, which demonstrated that Andromeda was well outside of our Milky Way Galaxy. Hubble announced his discovery of the Red Shift, which indicated that the universe was expanding, in 1929. He was measuring the red shifts of galaxies, not stars.

  • @MasterofFace
    @MasterofFace 5 років тому +1

    What's your interpretation on the electric universe people? Is it GR they hate or what?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  5 років тому +11

      It’s a hoax.

    • @MasterofFace
      @MasterofFace 5 років тому +1

      @@ProfessorDaveExplains Maybe for the thunderbolt project, but what about the sheep? You think this is a scam hoax for money or popularity or what?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  5 років тому +13

      Yep. Just like flat earth, only a little harder to debunk.

  • @Superplexmusic
    @Superplexmusic Рік тому

    You had me at the theme song

  • @Jesuisunknown
    @Jesuisunknown 2 роки тому

    In grand unified theory explains us that all forces the 1 before the grand unification epoch but gravity isn't a force according to Einsteins general relativity and those forces are carried by different bosons does that mean that all boson are just the same before the grand unification epoch can someone explain it to me plz?

    • @Evolcun
      @Evolcun 2 роки тому

      That is why we need a unified theory, one that explains gravity as a force while using the curvature of spacetime.

  • @FlatEarthKiller
    @FlatEarthKiller Рік тому

    Hello professor dave, was the big bang *basically* an explosion in nothingness that then produced a lot of atoms and energy, or is it more complicated than that? I am curious to know.

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  Рік тому +12

      Way more complicated. Start this astronomy series at the beginning.

    • @FlatEarthKiller
      @FlatEarthKiller Рік тому +3

      @@ProfessorDaveExplains Thank you very much. I am going to watch it tomorrow as i am going to sleep today.

    • @didierleonard7125
      @didierleonard7125 Рік тому

      The big band is NOT an explosion.. maybe one day we ll stop seing this every time we talk about it….

    • @FlatEarthKiller
      @FlatEarthKiller Рік тому

      @@didierleonard7125 Yeah, im the type of layperson on this topic.

    • @dogwalker666
      @dogwalker666 Рік тому

      Calling it "The Big Bang" was someone insulting the theory, Unfortunately the name stuck.

  • @rushoflife2368
    @rushoflife2368 2 роки тому +1

    Guys here me out, Dave needs a planetarium.

  • @philipinchina
    @philipinchina Рік тому

    Thank G-d for people like you.

  • @Seapatico
    @Seapatico 2 роки тому +1

    What I especially love about the Big Bang theory is that because it really can't make any predictions or assumptions about what existed before that instant, it actually leaves plenty of room for religious beliefs.
    I'm not at all religious, but the idea of a creator making the big bang seems rather elegant to me

    • @MouldMadeMind
      @MouldMadeMind 2 роки тому

      That just means theist can now claim that they are right and not being proven wrong is prove enought.

    • @drsatan7554
      @drsatan7554 2 роки тому

      How can there be a "before" the beginning of time?

    • @Evolcun
      @Evolcun 2 роки тому

      I mean, the thought of before time existed breaks all logic, so you cant make any predictions.

  • @thomasodle4558
    @thomasodle4558 4 роки тому +1

    i think that the big band did happen, but i don’t think that there was a dense ball before hand. There isnt enough evidence to say that there was one, but there is enough to show the universe is expanding.

    • @tjarkschweizer
      @tjarkschweizer 3 роки тому +1

      And if you go back in time, where do you end up? At the universe starting as a tiny dot. See it is pretty simple.

  • @TheKitsuneCavalier
    @TheKitsuneCavalier 4 роки тому +1

    Thousandth to like! This is the second time in my life to see that "999" become "1K!"

    • @umapradhan7626
      @umapradhan7626 4 роки тому +1

      I am ur first like

    • @TheKitsuneCavalier
      @TheKitsuneCavalier 4 роки тому

      I like that you are my first like, @@umapradhan7626 .

    • @chd72
      @chd72 3 роки тому +1

      Ok @@TheKitsuneCavalier

  • @rkreike
    @rkreike 2 роки тому

    Q: If there is a redshift of light in the universe because of distance,
    then galaxies that move away with constant velocity seem to move away with acceleration.
    If so, the bigbang-theory is possibly wrong?

    • @drsatan9617
      @drsatan9617 2 роки тому

      No lol
      The measurable expansion of the universe is one of the predictions of the big bang

    • @farel9476
      @farel9476 2 роки тому

      Every theory is "possibly" wrong. That's what makes them a theory

    • @onecoinmidas4541
      @onecoinmidas4541 2 роки тому

      Nope.

    • @LiLUndred
      @LiLUndred 2 роки тому

      I think it's because the redshift happens only if things go REALLY fast, like the expansion of the universe, or under EXTREME conditions, for example when getting close to a blackhole.

  • @nathanGC__
    @nathanGC__ 3 роки тому

    I also posed myself the same question as Olber 😅😂

  • @pastorslant
    @pastorslant 3 роки тому

    8:29 I don't understand how this is a prediction that proves anything? Isn't it circular reasoning to say the prediction of when galaxies started forming is true when you used the galaxies to determine the age of the universe in the first place?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  3 роки тому +13

      No, they are separate lines of reasoning. One is a calculation based on galactic recession velocities, the other is simulation data which then correlates with observation.

    • @pastorslant
      @pastorslant 3 роки тому

      @@ProfessorDaveExplains so, we don't calculate the age of the universe by the oldest observable galaxies? Was I just misinformed on that? Because my understanding was always that we see these galaxies that are X light-years away so the universe must be roughly X years old (that's obviously a drastic oversimplification, but you get my point). Is that not actually how the age of the universe is determined?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  3 роки тому +11

      Again, galactic recession velocities was the first method used. I believe it's explained in this video, as well as my other one on Edwin Hubble.

    • @pastorslant
      @pastorslant 3 роки тому +2

      @@ProfessorDaveExplains okay. I must've missed that. That makes more sense.

  • @nainavashal9630
    @nainavashal9630 5 років тому +3

    Nice professor dave

    • @leekfam7667
      @leekfam7667 4 роки тому +1

      Yes, Dave does have a nice professor

  • @cazyang2482
    @cazyang2482 4 роки тому

    awesome video, but really surprised to see that Georges Lemaître was not mentioned at all? he was the first guy to postulate that the recession of nearby galaxies can be explained by a theory of an expanding universe, after all.