Why Time and Space swap in a Black Hole

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  • Опубліковано 26 кві 2024
  • What is the difference between time and space? Why do time and space swap roles in a black hole? What is a Penrose diagram? All these answers in 12 minutes!
    0:00 - Light cones
    2:45 - Space and time
    4:56 - General relativity
    6:20 - Black holes
    10:13 - Collapse diagrams
    This video is narrated by Octave Masson.
    For more videos, subscribe to the UA-cam channel : / scienceclicen
    And if you liked this video, you can share it on social networks !
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    Alessandro Roussel,
    For more info: www.alessandroroussel.com/en
    _________________________________________________
    ScienceClic Français : / scienceclic
    ScienceClic Español : / scienceclices
    _________________________________________________
    To learn more :
    en.wikipedia.org/wiki/Light_cone
    en.wikipedia.org/wiki/Penrose...
  • Наука та технологія

КОМЕНТАРІ • 3 тис.

  • @ScienceClicEN
    @ScienceClicEN  2 роки тому +1074

    Hope you like this new video!
    About this video, it was a work of research, trying to find the most intuitive depiction of why time and space swap around inside a black hole. I wanted to find a set of coordinates, or a diagram, that would be mathematically accurate from the scientific standpoint, as well as being easily explainable in layman terms. For this, I have developed a more intuitive (in my opinion) version of Penrose diagrams, which, for those interested, consists in embedding the Penrose diagrams in the complex plane, and applying the conformal transformation z→z². This allowed me to generate a curved grid (used throughout the video, at 6:08 for instance), which is more intuitive than a Penrose diagram in the sense that "motionless" objects still move in straight horizontal lines, while clearly displaying the orientation of "time" and "space" (from Kruskal coordinates), and thus keeping lightcones oriented at 45° everywhere (thanks to the conformal transformation). Btw let me know if you have seen such a diagram before, I personally haven't, which surprises me since the construction is not so difficult to come up with. As a little bonus here is a preliminary simulation I had done while preparing for the video: ua-cam.com/video/L0UilXW34cs/v-deo.html
    About something else, if there are Spanish speaking people among you, don't hesitate to check out the new channel in Spanish. We will soon translate the main videos of this channel in Spanish. We just started it a few months ago, and it would help a lot if you share with your Spanish speaking friends or family 🙏 ua-cam.com/users/ScienceClicES

    • @whatsup3519
      @whatsup3519 2 роки тому +9

      I have a question when a ball fall from top, we can't reverse it . Which is similar to dropping ink to water which we can't able to reverse due to increased entropy. But when ball is falling down where can we see "disorder"? Could you please make a video about it or answer my question

    • @heikotessmann1964
      @heikotessmann1964 2 роки тому +3

      Yes! I do. Or in German: Ja, tu ich. Danke. Thanks.

    • @jayorag
      @jayorag 2 роки тому +3

      Gracias!

    • @Dr.RiccoMastermind
      @Dr.RiccoMastermind 2 роки тому

      Shiwn the topic in a very nice way, though I cant really see the switch to tine behaving as space and vice versa. Another German video tells, that movement through space now only allows one direction to the center (instead of 3 freedom grades outside) but time might be more freely moved through now 🤔
      However I dont see any ohysical reason why a black hole should be an empty sphere, but massive.
      How do we know if our physics still work right below the horizon, and does not only break in the very center (unlikely beeing of infininte density)?

    • @JubilantJerry
      @JubilantJerry 2 роки тому +11

      @@Dr.RiccoMastermind So there is no sudden transition, space and time are continuous and curve smoothly. A falling observer doesn't experience anything weird: if they are inside a small box with no windows (and assuming the black hole is much bigger than this box) they have no idea that the box is falling at all. So they can still move in 3 directions inside the event horizon.
      There actually is no single direction of time or space, there are multiple coordinate systems that are all valid. Like you can say the +x direction is your left and I can say the +x direction is your right, and both can be correct depending on how we draw the axes. A direction for time describes the world line of some observer. You can say the time direction follows your world line and therefore you move purely in the time direction, while someone in a fast spaceship can say that the time direction follows their spaceship and you are therefore moving backward and not purely in the time direction, both are correct depending on how the axes are drawn.
      Outside the event horizon, the direction that results in hovering at a fixed distance is a valid direction for time because observers can move in such a way. Inside the event horizon it's impossible to hover so no valid time direction points perpendicular to the radius. But it is in fact possible for observers to move directly in the radial direction so that becomes a valid direction for time. If chosen so, the other 3 directions: east-west, north-south, and past-future, would be the corresponding directions for space. So the event horizon marks a boundary where the intuitive coordinate system stops working and the weird one with time and space swapped starts working. But it's also just as possible to gradually change coordinate directions while getting closer, resulting in no sudden change at the horizon. Such are how the coordinates the video used work (if you're curious, the video uses Eddington-Finkelstein and later Kruskal / Penrose. The coordinates that have a sudden change at the event horizon is called Schwarzchild coordinates).

  • @MrHopecoreOfficial
    @MrHopecoreOfficial Рік тому +3930

    "The horizon of the black hole is no longer a place in space, but a moment in our past. And the centre of the black hole is no longer a point, but an event in our future... a destiny we cannot avoid" Something about this gives me chills

    • @naysay02
      @naysay02 Рік тому +162

      Yes! Beautifully captured the irresistible dark power of a black hole

    • @Dominus_Augustus
      @Dominus_Augustus Рік тому +116

      Truly terrifying, but also fascinating to say the least

    • @electriceyeball
      @electriceyeball Рік тому +43

      This must be how the Bene Gesserit in Dune feel

    • @annihilation777
      @annihilation777 Рік тому +4

      @@electriceyeball L

    • @Victor-ti4fx
      @Victor-ti4fx Рік тому +45

      Doesn't that mean we are currently falling towards a singularity?

  • @mrdre3628
    @mrdre3628 Рік тому +2068

    People underestimate how important good visualization graphics are to a complicated subject; I've understood the concepts of what you're saying for a while theoretically, but seeing it laid out so clearly definitely clarified things and I understand Penrose diagrams better as well so thank you...hopefully science educators can unlock the secrets of clear and understandable graphic design

    • @f1reflam3
      @f1reflam3 Рік тому +53

      Good visualization is not just important, it is often the key to understanding something. Visualization can in most cases make the difference between understanding a concept and not

    • @mrdre3628
      @mrdre3628 Рік тому +16

      @@f1reflam3 I agree completely

    • @rupertchappelle1089
      @rupertchappelle1089 Рік тому +3

      All gravity well graphics are wrong.
      The bottom of the well in in the center of the mass, not under it.
      See corrected gravity well model.

    • @Bassotronics
      @Bassotronics 7 місяців тому +5

      If this was all taught to me only in math form, I’d understand absolutely nothing. But an A.I. would understand everything!

    • @JugsKise
      @JugsKise 7 місяців тому +2

      @@rupertchappelle1089 Well, if the corrected gravity well model is correct, that would mean *most* gravity well graphics are wrong, not all 😉

  • @HodsBroo
    @HodsBroo Рік тому +424

    I've watched hundreds of hours of content and videos regarding 4D Space Time and I'm once again reminded at how the representations in your content are of the very best possible. You have a way of making things so simple and elegant, that they become easy to relate to and digest. Very good work.

  • @ARIY1411
    @ARIY1411 7 місяців тому +142

    This is the best video I have ever watched. The moment when you described how Space Time works visually was like an epiphany for me. Thank you for spending the time to create a video with such clear explanations. I hope you are able to continue making high quality videos.

    • @NoDarks
      @NoDarks 5 місяців тому

      Stupid consumer, why would you ever give someone on UA-cam money.

  • @labplay6771
    @labplay6771 2 роки тому +3516

    I like how you take pauses for us to grasp and figure everything out

    • @MrShtrudL
      @MrShtrudL 2 роки тому +86

      Couldn't agree more

    • @dramab7690
      @dramab7690 2 роки тому +51

      EXACTLY

    • @counterleo
      @counterleo 2 роки тому +102

      I still hit pause and uttered a loud *bruh* when he said the event horizon was no longer a place but an event in our past

    • @dharmatejamyneni4879
      @dharmatejamyneni4879 2 роки тому +37

      UA-cam ads : we have more pauses

    • @jacobshirley3457
      @jacobshirley3457 2 роки тому +12

      And having great visuals and background music also helps fill it out.

  • @igbaccin
    @igbaccin 2 роки тому +1210

    "If the apple falls, although it was motionless at first, it is because its future points downwards". This! This encapsulates the role gravity plays on time wonderfully. It felt like everything I read and watched on the subject suddenly clicked. The "aha!" moment! I deeply thank you for the insight.

    • @giacomofilippin12
      @giacomofilippin12 Рік тому +36

      Even if I already understood how and why that happens, this added a beautiful interpretation to it, really really perfect explanation

    • @davem1658
      @davem1658 Рік тому +6

      When in the video does he say about the apple had its "future point downwards"?? This wouldn't work on normal earth gravity (except black hole) as its future is not certain from the point of motionless in the air. It could be hit back upwards with something.... (your comment sounds like the apple's future was certain)
      I would state that the structure of space near a massive object distorts, constantly.... Continually going straight line to curve towards the center of the earth. Its this that starts the apple falling down. Time is the process of it falling. I don't think your idea of time in your comment is accurate.

    • @igbaccin
      @igbaccin Рік тому +8

      @@davem1658 But then do you think the idea of time presented in the video is at all accurate? I am directly quoting it starting at 5:50.

    • @davem1658
      @davem1658 Рік тому +4

      @@igbaccin Oh ok, you've directly quoted it. I've missed that.... I really have no idea, and I defer to your assessment. ... What I like to know is; the very exact moment the apple is motionless in space, what starts its trajectory on the curvature of space of falling down? What gives its initial push from 0 acceleration?

    • @igbaccin
      @igbaccin Рік тому +21

      @@davem1658 don't quote me on that since I am not at all an expert but I think the apple does not require any push because it is already has a trajectory through time.
      The apple, and everything else for that matter, is continually moving through time. It would only remain "floating" if it was in a region where spacetime is not distorted. I think this is the mind bending thing! You do not need to be pushed towards the earth if you are motionless within a region of spacetime that is distorted by earth's gravity. By virtue of moving through time (and of course always forward in time) your trajectory through time will meet the earth's trajectory through time. I think this is the rationale behind the quote at 5:50. You can even see the author displaying "stacking earths" at the bottom of the screen during this particular explanation to denote earth's movement through time (already illustrated at 0:54). I may be getting this all wrong, but this is what I understood from the video and from whatever else I consumed on the topic!

  • @martyd8175
    @martyd8175 Рік тому +93

    I'm a 50 year Old Irish man and has actually made me feel intelligent. What a fantastic way to illustrate the concept. The light cones have made everything fall into place. It's taken me 50 years to find something that allows me to grasp it!!!!

    • @Greenfist007
      @Greenfist007 5 місяців тому +2

      That's cause your a do'er not a dreamer . They have absolutely no idea what's going on it no doubt it will all change around in a few years time and then again a few after that. The only way to change the future is to do something . To act, not just sit there with your tongue hanging out the side your mouth drawing lines in the air.

    • @yngtylrdrdn
      @yngtylrdrdn 2 місяці тому +5

      ​@@Greenfist007what tf are you talking about?

    • @Greenfist007
      @Greenfist007 2 місяці тому

      I dont' know@@yngtylrdrdn

    • @toastycrystaleclxpse3423
      @toastycrystaleclxpse3423 Місяць тому

      @@yngtylrdrdn you see you are a dreamer not a do'er. They have absolutely no idea what's going on it no doubt it will all change around in a few years time and then again a few after that. The only way to change destiny is to absorb it yourself, then to combat it. To do, not just sit there with your tongue hanging out in space time tracing curves. That, is how one attains destiny.

    • @streetwiseyoungbull872
      @streetwiseyoungbull872 Місяць тому

      @@toastycrystaleclxpse3423consider yourself a smart man do you

  • @LAK_770
    @LAK_770 Рік тому +99

    There are SO many videos about these topics, some from eminent physicists in prestigious lectures, but they basically cover the same material and I’ve seen nearly all of them. But this video performed the rare feat of actually presenting something “new”. Never had I seen this topic presented with such distilled focus and clarity. Incredible video.

  • @kato_dsrdr
    @kato_dsrdr 2 роки тому +574

    The science community really need to give awards to people who teach us, ordinary people about science.. It's honestly a HUGE contribution for humanity..

    • @youngboy2pacdrake
      @youngboy2pacdrake 11 місяців тому

      it can come, there is a disease from a black hole named HM-248, it causes liver failure

    • @Emc4421
      @Emc4421 10 місяців тому +11

      Pay good teachers more!!

    • @Thumper770
      @Thumper770 7 місяців тому

      a real teacher will teach regardless of compensation. @@Emc4421

    • @Anolaana
      @Anolaana 7 місяців тому +6

      In the EU there is the Science Communication Prize.

    • @ChinCo1
      @ChinCo1 7 місяців тому +2

      Nice.@@Anolaana

  • @rikschaaf
    @rikschaaf 2 роки тому +518

    It's quite enlightening to see what is meant with time and space flipping when NOT looking at a penrose diagram. The 45 degree angle of time at the event horizon really makes it easier to understand.

    • @ScienceClicEN
      @ScienceClicEN  2 роки тому +84

      I'm glad you liked it! I also think it's easier to understand this way, Penrose diagrams are great but not really intuitive

    • @renaldohill5116
      @renaldohill5116 2 роки тому +26

      Agreed. I’ve never really understood what was meant by “they flip” this was a definite “ah ha” moment for me. So many other channels, such as Sixty Symbols are wonderful, but too often the scientists on there are like, you can’t explain these abstract concepts to a layman. Science Clic is like, hold my beer bruv and I love it.

    • @-_Nuke_-
      @-_Nuke_- 2 роки тому +3

      Roger Penrose is a genius!

    • @seraphik
      @seraphik 2 роки тому +7

      yeah, visualized this way it was so obvious and simple that i feel like a two year old would get it. yet up until now I've really really struggled with this concept! bravo science clic. truly the best relativity/cosmology channel.

    • @owlredshift
      @owlredshift 2 роки тому +4

      Einstein is a genius!

  • @sci_ent_ificsui_neg9236
    @sci_ent_ificsui_neg9236 Рік тому +18

    This is the best explanation I have ever seen for a layman. I've waited 10 years to fully comprehend this concept.

  • @C_Corpze
    @C_Corpze Рік тому +23

    I love how this is done, little pauses to allow us to catch up, simple explanation and good visuals that help picture it better. Thank you very much!

  • @marcelo.pastorelli
    @marcelo.pastorelli 2 роки тому +1058

    This is arguably the best science channel out there. Thank you for your efforts in sharing knowledge!

    • @jaredf6205
      @jaredf6205 2 роки тому +36

      Absolutely, more concepts have clicked for me from watching this channel than any other of the great physics channels.

    • @DragonKingGaav
      @DragonKingGaav 2 роки тому +6

      Most definitely!!!
      ScienceClic is In a Nutshell on steroids!!!

    • @ScienceClicEN
      @ScienceClicEN  2 роки тому +119

      Thank you very much it means a lot 🙏 I hope you'll enjoy the next videos!

    • @folepi7995
      @folepi7995 2 роки тому +3

      i dont agree. there are too many good channels on this topic.
      Its a fantastic channel to visualize the concempts and get new insights. But its not that simple as some videos of this channel might suggest.
      general relativity is so weird that you can interpret it in a thousand ways and alot seem right and wrong at the same time.
      to really understand more, you inevitably have to lean the calculations. There are some beatiful lectures on that on youtube.

    • @marcelo.pastorelli
      @marcelo.pastorelli 2 роки тому +1

      @@ScienceClicEN definitely will. Thank YOU

  • @studypurposeonly69
    @studypurposeonly69 2 роки тому +582

    This just blew my mind honestly! Since we can't access past events and the fact that space and time switch each other at the black hole, the outside of the black hole actually becomes an event in the past from a point in space! This is another elegant way of saying "Nothing can escape a black hole". Mind-boggling video as always

    • @JoseAndCode
      @JoseAndCode Рік тому +14

      In the incredible chance that we were to learn how to move backward in time, I wonder if this means we will be able to escape a black hole

    • @studypurposeonly69
      @studypurposeonly69 Рік тому +41

      @@JoseAndCode I am pretty sure at the time we discover how to travel back in time, we will simultaneously be able to discover of a way of escaping block hole

    • @anubhavpal5782
      @anubhavpal5782 Рік тому +4

      @@studypurposeonly69 true

    • @anubhavpal5782
      @anubhavpal5782 Рік тому +4

      @@JoseAndCode or maybe forward in time ? Since time slows down and is supposed to stop at the centre of the black hole. Meaning if we calculate correctly, we can enter black hole or stay close to the event horizon at one point in time and escape it at another point in the future ?

    • @halfjack2758
      @halfjack2758 Рік тому +3

      @@JoseAndCode by this analogy, since the light cone is turned towards the black hole, you could move backwards in time within the event horizon

  • @sgringo
    @sgringo 2 місяці тому +4

    I've watched this video several times over the past two years. Each time, I'm amazed anew at how brilliantly this nonintuitive concept is explained. This is, by far, the clearest description of time's relationship to general relativity that I have seen.

  • @steamyninja8881
    @steamyninja8881 2 місяці тому +2

    I’ve watched countless hours of science videos, but this video finally unlocked the meaning of space time for me. The explanation using light cones finally did it for me. I’ve got a clear understanding of it now. It felt like unlocking a dormant memory in my mind. Refreshing. Thanks

  • @eneafrancesco
    @eneafrancesco 2 роки тому +704

    Holy Moly! This channel has created by far the pedagogically highest quality way of teaching extremely complex subjects.
    Thank you so much for the great work that goes into these videos: they inspire me again and again in my interest in the universe, its rules, and in my efforts to inspire other people too!

    • @-_Nuke_-
      @-_Nuke_- 2 роки тому +24

      Yes this is by far lightyears away from channels like PBS spacetime where they confuse people instead of clarifying things to them!

    • @OregamiStars
      @OregamiStars 2 роки тому +2

      @@-_Nuke_- AGREED, PBS SpaceTime videos can be easy to get lost very quickly sometimes but this ?? my god-- this should be taught in all schools around the world, imo

    • @AverageAlien
      @AverageAlien 2 роки тому +5

      @@-_Nuke_- PBS doesn't confuse people, it just doesn't have nice visuals

    • @-_Nuke_-
      @-_Nuke_- 2 роки тому +1

      ​@@AverageAlien yeah visuals can really help grasp a concept as hard as these!

    • @dbooze148
      @dbooze148 2 роки тому

      Perfectly put!

  • @goga7301
    @goga7301 2 роки тому +247

    Your videos are criminally underrated. Such a masterpiece!

  • @shanegts2662
    @shanegts2662 3 місяці тому +3

    Spent so much hours watching black hole and spacetime vids believe me when say this one deserves an award.

  • @user-tx2vu7yn3w
    @user-tx2vu7yn3w 3 місяці тому +6

    Thanks for the pauses between sentences! I really needed those breaks, to understand what I just saw and heard

  • @ayushvyas4510
    @ayushvyas4510 2 роки тому +178

    I never truly understood the meaning of light cones concept... mentioned many times in other videos but never elaborated so beautifully....as soon as you turned that 2d to 3d...clarity was there ...
    Thanks a lot bro, you are a gift to this world 👍👍👍

    • @ScienceClicEN
      @ScienceClicEN  2 роки тому +33

      Thank you very much! Very glad you liked the visuals, it was a tough challenge to represent light cones in a video!

    • @ayushvyas4510
      @ayushvyas4510 2 роки тому +12

      @@ScienceClicEN seriously...I watched PBS which is good at visuals....but everyone representa the cones directly on space time grid and then reveal the Penrose diagram immediately....it doesn't give viewer the time to get the concept and visualise that its a 2d representation of a 3d sphere expanding....now it feels really really easy...

    • @ayushvyas4510
      @ayushvyas4510 2 роки тому +5

      @@ScienceClicEN visuals were as clean as one could make them... amazing mind you have got👏👏

    • @zazugee
      @zazugee 2 роки тому +6

      imagine you're walking in a dark place while holding a light torch and walking forward, you can't walk outside the lightcone of your torch

  • @timothynoll4886
    @timothynoll4886 2 роки тому +102

    1) This BLEW MY MIND because it gave me a whole new and much better perspective on how general relativity, space, time, gravity, and black holes work. 2) Thank you for the pauses between sentences because I would have been lost as heck otherwise.

    • @youngboy2pacdrake
      @youngboy2pacdrake 11 місяців тому

      it can come, there is a disease from a black hole named HM-248, it causes liver failure

  • @kryptobash9728
    @kryptobash9728 9 місяців тому +1

    Def the best video on UA-cam on understanding light, black holes, and just the fundamentals without getting confused. Very well done!!

  • @volcomsocom
    @volcomsocom 20 днів тому +1

    That cone analogy helped me grasp higher dimensions better than the traditional flatland analogy. Props for that.

  • @horizonvariations
    @horizonvariations Рік тому +257

    Fascinating to hear that it is not a black hole's huge amount of force that drags us to its centre, but a future event in time instead. Brilliant stuff!

    • @MrCmon113
      @MrCmon113 9 місяців тому +50

      Yeah under general relativity, gravity isn't a force at all and that distinction is actually important for the definition of an inertial frame.

    • @mariusg8824
      @mariusg8824 5 місяців тому +18

      Just to rephrase what the video already said: the reason why objects fall to earth, is because more future paths point towards earth than away from it. So an object with random movement will always fall towards the center.

    • @NoDarks
      @NoDarks 5 місяців тому

      Gravity is a force, and very observable, thanks redditor.@@MrCmon113

    • @NoDarks
      @NoDarks 5 місяців тому +2

      "huge force that drags us to center" it's because gravity pulls on time and space. Like obviously you're going to crash into something if it has gravity, this video is trying to make it way more "big brained" than it is.

    • @NoDarks
      @NoDarks 5 місяців тому +2

      And if it were the case that it's because "oh time is just pointing there dur hur" that breaks the whole speed of causality thing. I feel like science is just being made up at this point.

  • @pranayranjan3777
    @pranayranjan3777 2 роки тому +220

    This guy never fails to amaze us with his wonderful animations and easy to comprehend explanations... I Salute your efforts

  • @YASH-iz6tm
    @YASH-iz6tm 6 місяців тому +6

    The absolute best video to understand General Relativity. Although, I'm a physics undergrad and doesn't have it in my courseworlk but this channel has made me visualise the most counterintutive concepts. Kudos to your work!!

  • @bastion8320
    @bastion8320 Рік тому +3

    This has got to be the most interesting and terrifying video I’ve ever seen
    “The center of the black hole is your future” is an amazing phrase lol

  • @ltsecondincomand
    @ltsecondincomand 2 роки тому +40

    This has got to be the best explanation of how light cones and gravity are related I've ever seen. Its so good it made me retroactively understand videos I've watch before.

  • @aaqilkhan
    @aaqilkhan 2 роки тому +61

    This guy deserves his own TV show on Discovery Channel. Amazing the way he explains complex physics with intuitive and easy to understand animations. Great work!!!

  • @broken_radar
    @broken_radar Рік тому +6

    Thank you so much for this video! This is the clearest and must intuitive explanation of the time/space relationship in highly curved regions of space-time I have ever seen. Amazing work!

  • @Lertic
    @Lertic 8 місяців тому +1

    I find this video mind-blowing. Defining time as the "direction" of travelling light, and space as a perpendicular "plane", defies the human mind. While I could perfectly follow along your explanation, it's still a concept that's very hard to grasp in general. Nevertheless, you did very well in explaining!

  • @bettercalldelta
    @bettercalldelta 2 роки тому +211

    Beautiful explanation, I finally feel like I understood something about general relativity and black holes

    • @AverageAlien
      @AverageAlien 2 роки тому

      Keep putting Ukraine flags in your name, makes spotting idiots much easier

    • @kyleflanagan8410
      @kyleflanagan8410 Рік тому +3

      Zelensky had the deaths head emblem on the other day, they got all our baby formula too

    • @bettercalldelta
      @bettercalldelta Рік тому

      ​@@kyleflanagan8410 why do you comment this on non-political videos, kremlin bot?

  • @salvatoreventre8193
    @salvatoreventre8193 2 роки тому +26

    This guy should win a Nobel Prize for teaching Physics.

  • @jackblevins1201
    @jackblevins1201 Рік тому +3

    I love this video. I've learned everything in this video before, but this was a great refresher and the visuals were much more descriptive than in other videos.

  • @VinnyUnion
    @VinnyUnion Рік тому +3

    i'm just saying this once, i've watched a lot of things regarding this topic and ... this was by far, the most comprehensive explanation i've ever seen. not necessarily because i don't know but because i like to hear something new if possible and different ways of approaching such a topic.
    many channels have like those mathematical formulas and whatnot to sound extra smart.

  • @josephbanaszak9662
    @josephbanaszak9662 2 роки тому +35

    You just accomplished in 12 minutes what 12 years of schooling never could for me. Thank you for the amazing videos!!

  • @gianpa
    @gianpa 2 роки тому +85

    Mind blowing explaination as always.

  • @RuffianTux
    @RuffianTux 3 місяці тому +2

    This is worth a thumbs up just because at no point did he say "nothing, not even light, can escape."

  • @artdonovandesign
    @artdonovandesign Рік тому +1

    A really nice presentation!
    The graphics are perfectly conceived and the narration is clear and patient.

  • @FunkyDexter
    @FunkyDexter 2 роки тому +31

    Already 2 minutes in and you answered something i always asked myself, why light is placed at 45° in Penrose diagrams. This kind of intuition is rarely taught even in university.

    • @thedeemon
      @thedeemon 2 роки тому +7

      This video says it's 45 degrees because light speed is constant but that's not really the answer, any constant speed draws a cone of some fixed angle. It's only 45 degrees because we choose the scale of spatial and time axes such that light goes at 45 degrees.

    • @ScienceClicEN
      @ScienceClicEN  2 роки тому +38

      It's rather that light travels the same distance through space as it does through time, using natural units. In 1 year of time, it travels 1 light-year of distance. It can be considered an arbitrary choice of units, but it's not so arbitrary, it's the only choice of units that is "natural", in the sense that nature specifically gives us something invariant such that we can measure time and space with a same unit : light

    • @LuigiSimoncini
      @LuigiSimoncini 2 роки тому

      @@ScienceClicEN I recently discovered that the fact that " light travels the same distance through space as it does through time" is just a convention ua-cam.com/video/pTn6Ewhb27k/v-deo.html

    • @user-cj9jk1pd4g
      @user-cj9jk1pd4g Рік тому

      @@thedeemon Well, in order to do angles, you need to take arctan (y/x). But this only works if y/x is unitless, and if your y axis is in meters while your x axis in is seconds, well... it doesn't work.
      Instead, we label the x axis as "ct": the distance light travels. And because the distance light travels is equal to the distance light travels... arctan(y/x)=arctan(1)=45 degrees.

    • @thedeemon
      @thedeemon Рік тому

      @@user-cj9jk1pd4g Nope, this way you'd get 45 degrees only if c=1. This is the natural units the author mentioned.

  • @Axagoras
    @Axagoras 4 місяці тому +3

    This information is both awesome and terrifying all at once! You do a phenomenal job of explaining nearly incomprehensible concepts.

  • @NaomisCreativeArts
    @NaomisCreativeArts Рік тому +2

    I actually love this guys videos, the clarity, the accent, the animations, the graphics and the fact I learn more from just one of his videos that from all the years of classes with my science teacher.

  • @booJay
    @booJay 2 роки тому +52

    I'm going to say it: Best channel for explaining/visualizing physics concepts on UA-cam, and that's saying a lot considering I'm basically subscribed to them all.
    You really are doing a tremendous service. Please keep it up!

  • @BryanKern99
    @BryanKern99 2 роки тому +111

    Oh my goodness is what I kept repeating in wonder and amazement while watching this video, this is beyond simple scientific knowledge, this is an unbelievable new level. You’re truly a pedagogical and didactical genius to transmit things with this level of clarity, underrated channel that will explode

    • @-_Nuke_-
      @-_Nuke_- 2 роки тому +6

      yep 100%

    • @aniksamiurrahman6365
      @aniksamiurrahman6365 2 роки тому +8

      The greatest revelation I got is that the singularity isn't a place. It's an event, much like getting old or becoming father. So, one will not see the singularity as a point ahead of them, just as one doesn't see their older self sitting ahead of them. Rather, once past the event horizon, it will feel like the whole world is weirdly twisting, stretching and collapsing from all side, until everything is collapsed to (by GR*) a single point of nothingness.
      * GR = General Relativity.

    • @lpeabody
      @lpeabody 2 роки тому +1

      Yeah, channel has been blowing up steadily for a while. I distinctly remember it hovering around 10k subs even I first watched the general relativity visualization vid for the first time. It's been awesome seeing the channel grow.

    • @praveenawesome2182
      @praveenawesome2182 2 роки тому +1

      Yeah

  • @Mnerd7368
    @Mnerd7368 Місяць тому +1

    Did he just explanED how to "time travel" through the curvature of the fabric of spacetime continuum!? Beautiful explanation with visual graphics. This is the type of video i was looking for.

  • @johnbhai7147
    @johnbhai7147 Рік тому +10

    The animation was so good and understandable that for those who were not a physicist may enjoy greatly.

  • @CerealMJ
    @CerealMJ 2 роки тому +10

    It's extremely hard to find science channels that doesn't have stock footage as they explain certain concepts, but you nailed every single animation, narration, and explanation. Perfectly well done :)

  • @DoofEvil
    @DoofEvil 2 роки тому +22

    this is gonna take a few days and a few watchthroughs to fully understand and easily visualize, but wow what an amazing video. such a complicated topic explained so beautifully! i always love getting new ways to visualize and understand spacetime

  • @AngelGuzman0925
    @AngelGuzman0925 8 місяців тому +1

    I’ve watched videos trying to explain black holes and how it works with space time and I’ve always had an idea but this video’s graphics actually make me understand it especially the way it was described! Thank you

  • @sMcRea1
    @sMcRea1 4 місяці тому +7

    Thank you!.. I'm not a physicist but am fascinated by physics :-) I'm listening to the audio book From Eternity to Here by Sean Carroll. I was struggling with the concept of light cones which are fundamental. Now I can go back a couple of chapters and re-listen, thanks to your video :-)

  • @palanikumarasamy3677
    @palanikumarasamy3677 Рік тому +60

    9:44 the horizon of black hole is no longer a place. But a moment in our past and center of black hole is no longer a point, but a event in our future
    10:36 it is a light cone...rendered motionless by curvature of spacetime
    Ahhh....moments of this video to me. Thank you for your wonderful animations I never learned relativity with this clarity!!!

  • @DoctorRocker66
    @DoctorRocker66 2 роки тому +33

    This is the best description of a black hole I have ever seen. He gives a whole new way to comprehend why you can never escape a black hole. Well done sir, you just got yourself a new subscriber.

  • @nvmnx6698
    @nvmnx6698 9 місяців тому +1

    This was the best video i have watched in years, so comprehensive and clear. I am in love with these extremely rare gem-videos where everything is new and nothing is vague. Thank you so much, your work is amazing ❤❤❤

  • @teymoorazarpaad9167
    @teymoorazarpaad9167 Рік тому +1

    Thanks for describing the light cone so beautifully. Although I couldn’t follow your explanation after minute 9 or so. I must listen to it multiple times for sure to grasp the whole information. Thanks!

  • @vasilyp
    @vasilyp 2 роки тому +33

    I cannot believe even after all this time of knowing how extremely talented you are in communicating knowledge in such a unique way and after having watched all of your videos, that you can STILL amaze me and blow my mind off with perspectives I never had thought and most probably would never think of on my own! You are truly a prodigy! THANK YOU, THANK YOU, THANK YOU

  • @caruzo9631
    @caruzo9631 2 роки тому +15

    how this channel doesn’t have MILLIONS of subscribers is just way beyond me 🥶

    • @ScienceClicEN
      @ScienceClicEN  2 роки тому +2

      🙏

    • @literallybiras
      @literallybiras 2 роки тому

      Many science channels have been doing for a long time so I guess with patience he will be up there also, his content is very good

    • @caruzo9631
      @caruzo9631 2 роки тому +1

      @@ScienceClicEN Hello Mr ScienceClic,
      I was wondering if it would be worth making a video related to your GR and Gravity Videos about
      “how spacetime curvature behaves INSIDE planets”. Is there still a gradient inside when you have mass in all directions?
      I’m not educated enough to understand it but i can’t help but feel there must be some interesting things going on in there.
      LOVE your videos please never stop blessing us!

    • @praveenawesome2182
      @praveenawesome2182 2 роки тому

      @@literallybiras True

    • @randomkommentelo9015
      @randomkommentelo9015 Рік тому

      Because people don't care about stuff like this.

  • @testsalvador5695
    @testsalvador5695 Рік тому +7

    This needs more view. Simple, no drama, direct to the point with extremely clear visualization that suited general audience.

  • @davidkelley5382
    @davidkelley5382 Рік тому

    I have watched so many shows & vids on space, astrophysics & black holes. I have never heard it explained so concisely. Very well done, subscribe…

  • @Name-js5uq
    @Name-js5uq 2 роки тому +6

    Oh my goodness I am so happy you didn't change the music that is why I love listening to the show so much that music is awesome in the background and your videos just wouldn't be the same without them so thank you for choosing the same music I love it so much!

  • @hasanrudd9823
    @hasanrudd9823 7 місяців тому

    This is the best breakdown of this concept I've seen

  • @Expry24maciste
    @Expry24maciste Місяць тому

    I remember studying this subject at the university and I can say that this is one of the best explanations I've experienced. Good job.

  • @quickmana
    @quickmana 2 роки тому +9

    I keep learning this and feeling like I have a grasp on it, then discovering I was missing something critical and learning more! Thanks for the breakthroughs and looking forward to the next one!

  • @vigneshdesmond
    @vigneshdesmond 2 роки тому +3

    One of the greatest science channels I've ever seen, it really reinvigorated my interest in astrophysics. Also I absolutely adore the clean visuals and animations, the fantastic narration from Octave Masson, and the beautiful ambient background music - "Musique Mystérieuse". Thanks Alessandro Roussel, for your magnificent work!

  • @kelast203
    @kelast203 6 місяців тому +11

    3:20 also has the potential to be an excellent depiction of time dilation. If we assume each frame of that image were one hour apart, and one object were to move at relativistic speeds, the frames of the object would become increasingly spread out as it approached lightspeed; the other object would thus have relatively more dense time frames, and experience more hours within the same global time.

  • @brooksbutler8256
    @brooksbutler8256 2 місяці тому

    This was one of the best videos I watched on UA-cam in all of 2023. Still come back to this.

  • @dinoflame9696
    @dinoflame9696 2 роки тому +14

    Another banger. I discovered this channel after your visualization of relativity, and there are many good theoretical physics channels -- but you do it perfect in terms of pacing, level, description, comparisons etc.

    • @-_Nuke_-
      @-_Nuke_- 2 роки тому +1

      I think this was one of his very best so far, mind = blown!

  • @balritchengdshira625
    @balritchengdshira625 2 роки тому +3

    This is the most beautiful explanation I've heard in my life. Not even exaggerating.

  • @willmogann
    @willmogann 8 місяців тому

    This description and video were astonishingly good!

  • @alucarddracula7
    @alucarddracula7 Рік тому +2

    This was awesome. It was so carefully articulated that I almost think I could understand what you are talking about.

  • @loppol711
    @loppol711 2 роки тому +5

    Amazing videos as usual. High quality graphical depictions plus clear explanations makes this complex subject relatively easier to understand.

  • @rafaelvillalobos9145
    @rafaelvillalobos9145 Рік тому +7

    Awesome video! I've watched so many videos about black holes and timespace and gravity, but they never ever mentioned the concepts that this man discussed and I never really understood why light could not escape a black hole's gravitational effect.

  • @moralfuxery
    @moralfuxery 8 місяців тому

    This is honestly one of the BEST explanations of what we know/believe about these cosmic behemoths.
    Truly amazing content here mah friend.

  • @wochenendefussball
    @wochenendefussball 4 місяці тому

    I have seen many Videos about Black Holes, the speed of light and the Space in general. nobody explains it as easy and understandable as this Videos. They are so good thats incredible.

  • @jimwang3084
    @jimwang3084 2 роки тому +14

    I am a freshman student who wish to major in Physics specialist at the University of Toronto. Your videos are very awesome, they make very complicated stuff such as general relativity and quantum mechanics become very simple to understand. Hope there will be more wonderful videos released in the future.

    • @majorrgeek
      @majorrgeek Рік тому

      Jim Wang - when you get to learn some more physics you'll start to realize this video is a pile of crap

    • @youngboy2pacdrake
      @youngboy2pacdrake 11 місяців тому

      it can come, there is a disease from a black hole named HM-248, it causes liver failure

  • @Doodle1283
    @Doodle1283 2 роки тому +3

    I've never thought about a black hole and spacetime this way. This is just mind blowing.

  • @momotheorangecat
    @momotheorangecat 9 місяців тому

    this has got to be my favourite video, i keep coming back to it everyday. it's just so well made! showed it to all my friends :)

  • @karenkfoury7047
    @karenkfoury7047 Рік тому

    i love your channel and am very grateful for your videos. i keep coming back to your videos especially this one. you are amazing and the visuals are super helpful. hope you keep it up and keep on uploading. thank you for what you do.

  • @stevenschilizzi4104
    @stevenschilizzi4104 2 роки тому +7

    An absolutely excellent presentation, brimming with clarity (in spite of black holes!). ScienceClic remains as brilliant as ever. Thank you!

  • @chriskaplan6109
    @chriskaplan6109 2 роки тому +3

    Perhaps the most easy to grasp and intuitive explanation of light cones and the swapping of these dimensions within a black hole. Excellent content!

  • @jojnokirk8035
    @jojnokirk8035 Рік тому

    this is without a doubt the greatest explanation of black holes, spacetime, and general relativity i've ever had the pleasure of watching

  • @behrwillsonn4842
    @behrwillsonn4842 Рік тому

    I've seen a lot of these videos, and this one is a good one. It's cool that he lingers on the images so I can fully understand what he's saying instead of the images going by as fast as a conversation.

  • @GD15555
    @GD15555 2 роки тому +10

    the best explanation ever! I think I can build a time machine after watching this

    • @ScienceClicEN
      @ScienceClicEN  2 роки тому +5

      Haha send me an email when you're done I'd be curious to try it

    • @joshuaschulze7545
      @joshuaschulze7545 2 роки тому +6

      @@ScienceClicEN Service is spotty. I sent it tomorrow, you should receive it last week.

  • @stevemonkey6666
    @stevemonkey6666 2 роки тому +12

    You have explained this concept really well. I have seen other channels try to explain it but not nearly as well.

  • @bilge677
    @bilge677 7 місяців тому

    Wow, everything in this video is explained very well, with very good visuals. Earned a like from me

  • @j.d.waterhouse4197
    @j.d.waterhouse4197 Рік тому

    Best graphic explanation I've ever seen, excellent!

  • @juliamorales7355
    @juliamorales7355 2 роки тому +3

    Finally! I've been waiting for your basic explanation for years when the physics kept evolving and I needed the missing lower concepts before moving to the more advanced concepts are presented. Thank you. Is like learning to divide before learning to add and subtract.
    .

  • @JordiR243
    @JordiR243 2 роки тому +3

    I don't usually leave comments, but this is so well made I have to express my appreciation. This is the best video I've seen on black holes!

  • @rubenlarochelle1881
    @rubenlarochelle1881 6 місяців тому

    Wonderful way to explain it! Magnificient job!
    Sometimes you think you know something, until someone finds a genius way to describe it from a different and simpler point of view, which not only makes you understand it better, but also allows you to teach it to others.
    Brilliant, just brilliant!

  • @straightup7up
    @straightup7up 7 місяців тому +1

    This really helped me understand the difference between time and space , super visualizations!

  • @gmrecneps
    @gmrecneps 2 роки тому +4

    Thank you so much for putting this and all of your other videos together. Each is a truly monumental achievement. A global treasure. A timeless artifact of the achievements of our species. Please keep making more. You are changing the world.

  • @batbawls
    @batbawls 2 роки тому +5

    This series of videos are absolutely amazing. Fantastically brilliant.

  • @kfa013
    @kfa013 3 місяці тому

    Thank you for the “professional” explanation (the best one) and now i see why most UA-camrs dont explain black hole in this details

  • @emergentform1188
    @emergentform1188 Рік тому

    Wow that's some seriously cool stuff. Loving this content dude. It amazes me that, no matter how much I learn about such things, there are still new idea I've never come across before such as this one.

  • @FatHoles
    @FatHoles 2 роки тому +3

    One of the best explanations I’ve ever heard and seen. Thank you so much!

  • @NovaWarrior77
    @NovaWarrior77 2 роки тому +3

    The "collapse diagram" timestamped part is absolutely brilliant.

  • @kevikama9659
    @kevikama9659 7 місяців тому

    This is the best video I have seen explaining this phenomenon.

  • @Puppeteer_in_the_Void
    @Puppeteer_in_the_Void 8 місяців тому

    Thank you so much, until now I haven't been able to understand the bigger picture as well as this, instant subscriber, I hope my understanding of the universe continues to deepen with your channel.

  • @Flobbled
    @Flobbled 2 роки тому +6

    This was a phenomenal explanation! The animations are super helpful.