Richard Feynman - The Distinction of Past and Future. Part 3

[culwin]

Can I get college credit for watching these videos?

[MetalMilitia5488]

Using "order" is fine for ideal systems, such as the blue/white solution discussed here by Feynman, but it can be somewhat misleading in complex systems, for example, colloidal or block copolymer self-assembly, or the formation of micelles or lipid membranes. One might think a micelle is an "ordered" structure, and should not form from a "disordered" solution; however, the solution is not ideal, and the minimization of free energy results in the formation of micelles.

[reksub10]

the past and future are a gift thats why we live in the present .... boom boom

[BlameRepublicans]

Chick I would pork @ :35

[IlRezzonico]

@BlameRepublicans she's now 65 years old....

[DarthPickley]

there are many more states in which a certain object is considered "ordered" than for which it is considered "disordered", however a specific state, considering every particle's position, is as likely as any other. You can consider something happening over time as well; where the probability of things becoming more disordered due to chaos is much more likely than for, say, the motions of the world to coalesce into the injection of energy into a rolling cart as reverse friction.

[MetalMilitia5488]

@DarthPickley There are actually more states for a "disordered" system. From Boltzmann's equation, we have the entropy S = k*ln(W), where W is the multiplicity of the system, or effectively, the number of configurations or states. A higher entropy  corresponds to a larger number of configurations (and a more disordered system). A system at maximum entropy is the most probable observation, since there are more states available.

[texkeks]

I would love to ask him about what he felt order was.

[lazurm]

@texkeks He would probably answer by talking about entropy which states that the universe inevitably goes from an ordered state, where all its energy (actually the great majority of it, excluding the minute fluctuations that inevitably occur due to quantum fluctuations) is evenly distributed, to an unordered state where the energy becomes less evenly distributed. Or, that due to entropy, your bedroom will inevitably become disorder unless energy is applied to bring it back to a state of order.

[texkeks]

@lazurm I am familiar with the term. The bedroom could only be ordered if energy were put into it to begin with, though it all depends on what you define "order" as.

[Ryakki]

@lazurm

Even distribution is entropy, order is the concentration of matter and energy in to discrete places especially when they form structures or systems.

[lazurm]

@Ryakki Yes, in the example of fluids that were, at first, separated, entropy would depict even distribution but, in referring to the universe as a whole, this isn't true. What we are referring to is the amount a system is in equilibrium where high equilibrium supposes less entropy and, currently, the universe is anything but, especially when comparing it to its original state. Any local decrease in entropy results in an increase of entropy (via heat radiation). Order to disorder.

[tml4873]

@texkeks I think he would have objected to the term "felt". Order, in physics, is a defined term. It's not a philosophical question. He didn't explain order in the lecture because the students are assumed to have a basic knowledge of such terms.