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Ok, thanks guys. Quantum uncertainty is the reason we can't reach zero Kelvin, so it's kind of nonsense to ask why quantum effects still work at absolute zero.

Ok, thanks guys. Quantum uncertainty is the reason we can't reach zero Kelvin, so it's kind of nonsense to ask why quantum effects still work at absolute zero. > It's not physically impossible for order to increase, it's just ridiculously unlikely. Would love to see resources that explain this (I think it comes down to quantum uncertainty again). > the basic idea is that the probability for anything to happen is different than 0 Yeah, quantum uncertainty. Still can't wrap my head around it, but in conversations with physicists, they also weren't sure why the heck it works that way. Gonna read my quantum mechanics book, but the math is not easy-going and especially quantum logic with its 3 states (true, false and flying spaghetti monster superposition) is extremely difficult to grasp using intuition. It contains a lot of thinking from statistics which essentially is just extremely unintuitive as well. - - - Edit: I really wonder if something like a "gravitational quantum electrodynamics" (don't know if we achieve it with this specific theory) or string theory (I don't really like it due to its unscientific nature) - in essence a Theory of Everything - will really explain everything like it really is or just happens to be a fitting model without being any meaningful representation of reality (in the sense that it explains how the underlying reality really looks like). We won't be able to verify if our models are actually representing reality anyways (any theory that explains all observed events and which has some plausible and strong predictions can be treated as a possible reality), but would be nice to know. Guess it can't physically happen, unfortunately.

duckerude 8y ago
Imagine you have a box with red marbles and blue marbles. You start shaking it. The marbles get mixed up. Pretty soon, they're completely mixed up. That's maximum entropy. Now imagine you keep shaking the box for a few years or so. Just by sheer coincidence, they might end up neatly sorted for a few seconds every now and then. That's like a Boltzmann brain. I think that's all there is to it in principle, but I'm not very informed.
- mockingbirdy 8y ago
  > you keep shaking the box for a few years or so That was the part I was unsure about: Does the universe keep on shaking? The answer seems to be: Due to quantum uncertainty - yes. Why? No one really knows because we don't have a god-damn clue about why the universe works the way it works (although we have a good understanding how the universe works in many points, but not a coherent theory or framework that gives a conflict-free explanation).
  - duckerude 8y ago
    Why wouldn't it keep on shaking? Energy doesn't go away. Things don't necessarily stop moving. Again - the universe doesn't cool down to absolute zero. It's called "heat death" for a different reason. You don't need anything quantum for this. Simple Newtonian mechanics seem enough.
    - mockingbirdy 8y ago
      I thought that an equilibrium in which the energy is distributed evenly is a state which the universe can reach. In that state, there wouldn't be something that shakes after a long while. But yeah, maybe energy conservation principles alone can explain that it keeps shaking. But it still feels so unintuitive that it doesn't slow down or cool down. I still have those other models in mind that the universe expands and then collapses or it keeps on expanding (which seems to be the case) or simply stop to expand but also doesn't collapse (and proceed to have maximum entropy level). Those were the three models I got taught. It seems that the universe is flat and will expand endlessly, so the model I thought is right (the universe just stops to expand) isn't true and my related assumptions (that maximum entropy levels get reached and absolute zero) are also not true (for some different reasons like quantum certainty and - it seems - even simple Newtonian mechanics). related SMBC: https://www.smbc-comics.com/comic/2014-06-02 https://www.smbc-comics.com/comic/2014-06-02

duckerude 8y ago

Imagine you have a box with red marbles and blue marbles. You start shaking it. The marbles get mixed up. Pretty soon, they're completely mixed up. That's maximum entropy. Now imagine you keep shaking the box for a few years or so. Just by sheer coincidence, they might end up neatly sorted for a few seconds every now and then. That's like a Boltzmann brain. I think that's all there is to it in principle, but I'm not very informed.

mockingbirdy 8y ago
> you keep shaking the box for a few years or so That was the part I was unsure about: Does the universe keep on shaking? The answer seems to be: Due to quantum uncertainty - yes. Why? No one really knows because we don't have a god-damn clue about why the universe works the way it works (although we have a good understanding how the universe works in many points, but not a coherent theory or framework that gives a conflict-free explanation).
- duckerude 8y ago
  Why wouldn't it keep on shaking? Energy doesn't go away. Things don't necessarily stop moving. Again - the universe doesn't cool down to absolute zero. It's called "heat death" for a different reason. You don't need anything quantum for this. Simple Newtonian mechanics seem enough.
  - mockingbirdy 8y ago
    I thought that an equilibrium in which the energy is distributed evenly is a state which the universe can reach. In that state, there wouldn't be something that shakes after a long while. But yeah, maybe energy conservation principles alone can explain that it keeps shaking. But it still feels so unintuitive that it doesn't slow down or cool down. I still have those other models in mind that the universe expands and then collapses or it keeps on expanding (which seems to be the case) or simply stop to expand but also doesn't collapse (and proceed to have maximum entropy level). Those were the three models I got taught. It seems that the universe is flat and will expand endlessly, so the model I thought is right (the universe just stops to expand) isn't true and my related assumptions (that maximum entropy levels get reached and absolute zero) are also not true (for some different reasons like quantum certainty and - it seems - even simple Newtonian mechanics). related SMBC: https://www.smbc-comics.com/comic/2014-06-02 https://www.smbc-comics.com/comic/2014-06-02