I don't believe the 2nd law of thermodynamics. (The most uplifting video I'll ever make.)

Published 2023-06-17
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The second law of thermodynamics says that entropy will inevitably increase. Eventually, it will make life in the universe impossible. What does this mean? And is it correct? In this video, I sort out what we know about the arrow of time and why I don't believe that entropy will kill the universe.

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00:00 Introduction
1:00 The Arrow of Time
3:04 Entropy, Work, and Heat
7:07 The Past Hypothesis and Heat Death
9:34 Entropy, Order, and Information
11:38 How Will the Universe End?
15:46 Brilliant Spons

All Comments (21)
  • @MrEiht
    As Abba said: "Entropy killed the radio star..."
  • I have witnessed water running upwards from a ditch onto a road then becoming airborne and creating a cloud. But, it was because of a tornado passing near to my house and I hope never to see anything like that again.
  • @tayzonday
    If I don’t shower, all the good air in a room definitely moves into the corner.
  • @olive_oil87
    “and luckily so because it would be inconvenient if you entered a room and all the air went to a corner” just made my day
  • @deebarker1969
    Sabine, I'm a chemist, and in conversations in the past, I attempted to make the arguments about entropy you've made so eloquently in this video (especially the associations/ideas about order). From now on, rather than arguing, I'll recommend watching your video. Thank you so much for this great video!
  • @truejim
    “My videos can only go downhill from here…” The perfect ending to a video about entropy! 😂
  • @ToddPangburn
    THANK YOU for pushing back against entropy being described as order vs. disorder! Through years of schooling entropy was this poorly defined, almost spooky concept of order. Then I was finally introduced to entropy as probabilities of microstates (with gas in a box), and it was completely logical and clear.
  • @Thomas-gk42
    To some of your vids, I come back months later again and again, because they are lovely every time new. This is one of them.
  • @markusk2289
    This video reminds me how it always frustrated me in school as well as later at Uni that things were described or defined in simplified ways that made them wrong, harder to actually grasp or both. Sometimes the actual truth of the matter would slowly reveal itself often leading to an „aha“ moment years later and a feeling of „I knew it“. Also funny how oftentimes simply explaining the meaning of a latin or greek term would have almost explained the whole concept behind it, yet somehow no professor ever did that.
  • Aging biologist here! I’d like to add an uplifting comment to this uplifting video. :) I’m always a bit sad to see entropy given as the reason we get old. As Sabine discusses later in the video, open systems with access to a source of low entropy can use that to decrease their own entropy, so given that we can take in low-entropy food, there’s no in-principle reason we couldn’t use this to keep the entropy of our bodies roughly constant with time. So not aging is totally allowed by the laws of physics! It’s even well within the laws of biology—there are plenty of animals that don’t age, from tiny hydra to giant tortoises, and even one of nature’s most beautiful animals, the naked mole-rat. Their risk of death and disease doesn’t change with time, which basically means they keep their entropy constant throughout their adult lives. Now all we need to do is crack this biological entropy preservation using science…but that’s another story!
  • @Cre8tvMG
    I enjoy your sense of humor keeping things light and entertaining while simultaneously tackling deep concepts. Great blend.
  • @un4given868
    Thank you for making clear to me what entropy is and as a bonus giving me a solid idea of what Necessity could mean as well .
  • I completely agree with you. When I was young, I used to tell my mom that my room was never in disorder because disorder itself doesn't truly exist. Instead, what exists are infinite states of possible order, and none of them holds more inherent sense than another.
  • @AlexanderTome
    This has brought me closer to reconciling questions I've had about entropy than I've ever been before. Thank you for that.
  • @ShipOfFreaks
    This is a great philosophical point. I love your subtlety, Sabine.
  • @elizabethco6116
    I’ve been hoping to hear something like this from you. Thank you for this.
  • @maninspired
    I'm a mechanical engineer who focused on thermodynamics in college. Despite years of study and using entropy in formulas, this is by far the best explanation of entropy I've ever heard.
  • @SeattleShelby
    Sabine’s Carnot efficiency at explaining this stuff is 100%.
  • @huynguyen4450
    Thanks Sabine! This makes me appreciate my current stat mech class more!