Not the most accurate of thermodynamic explanations or demonstrations, but I realize after watching that wasn't the point of the video. Cool trick though for sure. I suspect I know how it coulda been done, but not really sure. I see you're already in a debate with about 50 different people about the accuracy of your science so I will let you duke it out with them:).
@Ripley747 Thanks for your comments! Yeah, it's just a trick I needed an idea for. Notice how "I attempt to demonstrate this idea". I'm a physics graduate - I could split hairs over this - but it's just a bit of fun! However, debating is also fun so please feel free to join in!
@mrwhite692000 Well, then I'll throw this out there. Not debating, just curious on your thoughts. What are your thoughts that even Maxwell's Demons don't violate the 2nd law? If you're unaware of this concept, it states (paraphrasing) Maxwell's Demons would require more entropy to function properly since it would create more entropy overall. That is, the "trap door" would produce more entropy in order for it to distinguish the difference between a high energy and low energy molecule. Thoughts?
@Ripley747 yes, it's a fair assumption to make and, yes, there are real Maxwell's demons out there in the world but they must, at least, produce as much entropy as they reduce. See my reply to StefSSU and you'll see my thoughts on this. It all depends on how you define what a Maxwellian demon actually is.
I was under the impression that the thought experiment of maxwells demon was deemed impossible, as any experiment used to measure the speed of the relative particles conducted by the demon would add energy into the system, breaking it down... ie, the demon cannot measure the speed of the particles to allow through the door without affecting said particle.
The idea of it was not deemed impossible but what was forgotten was that the demon itself does work and, therefore, increases the entropy, not energy. In other words, if you want to decrease entropy in one place you have to increase it somewhere else.
But Maxwell's Demon, by definition, does not expend energy, therefore it would not increase the entropy of its own system and defy the Second Law. In using that definition, it would be deemed impossible because no being exists which can do work without expending energy/increasing entropy.
This is wrong and a misrepresentation of the thought experiment. Maxwell's demon is not defined to not expend energy. These are Maxwell's own words:
"if we conceive of a being whose faculties are so sharpened that he can follow every molecule in its course, such a being, whose attributes are as essentially finite as our own"
There is no mention of not expending energy as you suggest.
But further in that same quote, we see: "He will thus, without expenditure of work, raise the temperature of B and lower that of A, in contradiction to the second law of thermodynamics...." In physics, work and energy are of the same relation as debt and payment. If work is done, energy must be expended to pay for it. So by the laws of physics, this equates to Maxwell's Demon not expending energy to do his job. ??? Still confused.
"If work is done, energy must be expended to pay for it."
If by "expend" you mean use, this is not the case. Energy is conserved. I do not disagree that to do work you require energy but what thermodynamics teaches us is that you can have an abundance of energy without being able to do work. This happens when a system is in thermodynamic equilibrium.
Well, since the dictionary defines "expend" as "to spend or use", then yes, that's what I meant. :-p As far as the rest of your statement, how does it relate to the demon and the case for/against it? Can you cite the reference for you definition of Thermodynamic Equilibrium, because nothing I've found directly correlates to your statement.
Well since you're saying energy can be used then I'm afraid this is simply not true by the conservation of energy.
The Wikipedia definition of thermodynamic equilibrium is good enough. Check out the Wikipedia article on heat engines and look at the subsection "efficiency". You'll find when Tc=Th you can't do any work. This can be generalised to any system that can do work, i.e. Maxwell's demon.
Okay, but back on point, the same quote you used earlier also said Maxwell's demon does its job "without expenditure of work" (or energy, as I've shown means basically the same according to the laws of physics.) Yes, the system in equilibrium can't do the work itself, so Maxwell's demon comes and does it without using any energy and thus without offsetting the decrease in entropy of the system. Therefore it would be impossible, no? Nothing like that exists in nature.
The demon may well be defined as doing this task of sorting molecules out without doing work but this, in reality, is impossible. You need energy to do work. A consequence of doing work is that you always increase the entropy of the system except in the case where the process is reversible, in which case the entropy stays the same.
So, contrary to your original response, you agree with me? Did I really just waste this much time for you to contradict your original statement to StefSSU about how the idea could not be deemed impossible? I had hopes of something actually coming from this... but I suppose one should not expect to learn physics from a guy doing card tricks. I mean, no offense, but if I wanted to chase my tail I'd take lessons from the dog. Peace.
Well if you've taken nothing from this discussion then that's you're own fault, not mine. Same goes for wasting your own time.
Additionally, the fact that, as Maxwell's demon is defined as not expending work to achieve the task may well be impossible but what I was disagreeing with is that Maxwell's demons do actually exist. It is possible to separate out mixtures such as is described, however, you must do work to achieve this end.
Here is the message that I have so evidently failed to communicate to you:
"Several physicists have presented calculations that show that the second law of thermodynamics will not actually be violated, if a more complete analysis is made of the whole system including the demon... a real-life Maxwell's demon would need to have some means of measuring molecular speed, and that the act of acquiring information would require an expenditure of energy."
Thanks, I think this is one of the first effects I'm truly happy with performance wise. The video needs work however and the camera I'm using is quite poor!
I do apologise for the bad recording. Hopefully I'll soon be able to invest in a decent camera that doesn't decide to change its exposure settings throughout a recording!
Not the most accurate of thermodynamic explanations or demonstrations, but I realize after watching that wasn't the point of the video. Cool trick though for sure. I suspect I know how it coulda been done, but not really sure. I see you're already in a debate with about 50 different people about the accuracy of your science so I will let you duke it out with them:).
Ripley747 1 year ago
@Ripley747 Thanks for your comments! Yeah, it's just a trick I needed an idea for. Notice how "I attempt to demonstrate this idea". I'm a physics graduate - I could split hairs over this - but it's just a bit of fun! However, debating is also fun so please feel free to join in!
mrwhite692000 1 year ago
@mrwhite692000 Well, then I'll throw this out there. Not debating, just curious on your thoughts. What are your thoughts that even Maxwell's Demons don't violate the 2nd law? If you're unaware of this concept, it states (paraphrasing) Maxwell's Demons would require more entropy to function properly since it would create more entropy overall. That is, the "trap door" would produce more entropy in order for it to distinguish the difference between a high energy and low energy molecule. Thoughts?
Ripley747 1 year ago
@Ripley747 yes, it's a fair assumption to make and, yes, there are real Maxwell's demons out there in the world but they must, at least, produce as much entropy as they reduce. See my reply to StefSSU and you'll see my thoughts on this. It all depends on how you define what a Maxwellian demon actually is.
mrwhite692000 1 year ago
I was under the impression that the thought experiment of maxwells demon was deemed impossible, as any experiment used to measure the speed of the relative particles conducted by the demon would add energy into the system, breaking it down... ie, the demon cannot measure the speed of the particles to allow through the door without affecting said particle.
StefSSU 2 years ago
The idea of it was not deemed impossible but what was forgotten was that the demon itself does work and, therefore, increases the entropy, not energy. In other words, if you want to decrease entropy in one place you have to increase it somewhere else.
mrwhite692000 2 years ago
yeah sorry, i worded my comment poorly, but thats what i meant; that entropy would only increase.
StefSSU 2 years ago
But Maxwell's Demon, by definition, does not expend energy, therefore it would not increase the entropy of its own system and defy the Second Law. In using that definition, it would be deemed impossible because no being exists which can do work without expending energy/increasing entropy.
discosqueakyfly 2 years ago
This is wrong and a misrepresentation of the thought experiment. Maxwell's demon is not defined to not expend energy. These are Maxwell's own words:
"if we conceive of a being whose faculties are so sharpened that he can follow every molecule in its course, such a being, whose attributes are as essentially finite as our own"
There is no mention of not expending energy as you suggest.
mrwhite692000 2 years ago
Comment removed
discosqueakyfly 2 years ago
But further in that same quote, we see: "He will thus, without expenditure of work, raise the temperature of B and lower that of A, in contradiction to the second law of thermodynamics...." In physics, work and energy are of the same relation as debt and payment. If work is done, energy must be expended to pay for it. So by the laws of physics, this equates to Maxwell's Demon not expending energy to do his job. ??? Still confused.
discosqueakyfly 2 years ago
"If work is done, energy must be expended to pay for it."
If by "expend" you mean use, this is not the case. Energy is conserved. I do not disagree that to do work you require energy but what thermodynamics teaches us is that you can have an abundance of energy without being able to do work. This happens when a system is in thermodynamic equilibrium.
mrwhite692000 2 years ago
Well, since the dictionary defines "expend" as "to spend or use", then yes, that's what I meant. :-p As far as the rest of your statement, how does it relate to the demon and the case for/against it? Can you cite the reference for you definition of Thermodynamic Equilibrium, because nothing I've found directly correlates to your statement.
discosqueakyfly 2 years ago
Well since you're saying energy can be used then I'm afraid this is simply not true by the conservation of energy.
The Wikipedia definition of thermodynamic equilibrium is good enough. Check out the Wikipedia article on heat engines and look at the subsection "efficiency". You'll find when Tc=Th you can't do any work. This can be generalised to any system that can do work, i.e. Maxwell's demon.
mrwhite692000 1 year ago
Okay, but back on point, the same quote you used earlier also said Maxwell's demon does its job "without expenditure of work" (or energy, as I've shown means basically the same according to the laws of physics.) Yes, the system in equilibrium can't do the work itself, so Maxwell's demon comes and does it without using any energy and thus without offsetting the decrease in entropy of the system. Therefore it would be impossible, no? Nothing like that exists in nature.
discosqueakyfly 1 year ago
The demon may well be defined as doing this task of sorting molecules out without doing work but this, in reality, is impossible. You need energy to do work. A consequence of doing work is that you always increase the entropy of the system except in the case where the process is reversible, in which case the entropy stays the same.
mrwhite692000 1 year ago
So, contrary to your original response, you agree with me? Did I really just waste this much time for you to contradict your original statement to StefSSU about how the idea could not be deemed impossible? I had hopes of something actually coming from this... but I suppose one should not expect to learn physics from a guy doing card tricks. I mean, no offense, but if I wanted to chase my tail I'd take lessons from the dog. Peace.
discosqueakyfly 1 year ago
Well if you've taken nothing from this discussion then that's you're own fault, not mine. Same goes for wasting your own time.
Additionally, the fact that, as Maxwell's demon is defined as not expending work to achieve the task may well be impossible but what I was disagreeing with is that Maxwell's demons do actually exist. It is possible to separate out mixtures such as is described, however, you must do work to achieve this end.
mrwhite692000 1 year ago
Here is the message that I have so evidently failed to communicate to you:
"Several physicists have presented calculations that show that the second law of thermodynamics will not actually be violated, if a more complete analysis is made of the whole system including the demon... a real-life Maxwell's demon would need to have some means of measuring molecular speed, and that the act of acquiring information would require an expenditure of energy."
- Wikipedia
mrwhite692000 1 year ago
where can i get this song?
bebopalulahola 3 years ago
It's called "Sunshine Recorder" by Boards of Canada
mrwhite692000 3 years ago
i like the vid but i dont get whats really supposed to be happening...could somebody please fill me in?
harpooned 3 years ago
Wow...Excellent!!! 5 stars
agustin1955 4 years ago
Thank you very much agustin. I enjoy your coin tricks very much.
mrwhite692000 4 years ago
Great stuff, you are right you do need a better camera, this one doesnt do the tricks justice
magicmand32 4 years ago
Excellent premise, well done.
CrdShk 4 years ago 2
Thanks, I think this is one of the first effects I'm truly happy with performance wise. The video needs work however and the camera I'm using is quite poor!
mrwhite692000 4 years ago
very nice
love your Card and Spongeball tricks
denkste144 4 years ago 2
Cheers mate, loving your latest video also :-)
mrwhite692000 4 years ago
I do apologise for the bad recording. Hopefully I'll soon be able to invest in a decent camera that doesn't decide to change its exposure settings throughout a recording!
mrwhite692000 4 years ago
haha man!!! that was sooo cool :D
I'd love to see that live :P:P
gg... 5/5 :D keep it up
deathlordnwa 4 years ago 2
Thanks a lot mate, I'll try my best :-) More should be coming soon.
mrwhite692000 4 years ago