# Entropy in everyday life

Discussion in 'General Philosophy' started by wegs, May 20, 2019.

1. ### DaveC426913Valued Senior Member

Messages:
18,673
OK, if I didn't know you, I'd accuse you of trolling.

You may have read it all, but you clearly have not grasped anything I've said in the last dozen posts. You pretend like you still think this has to be a real experiment.

D:"Let's posit a craft that can get to A.Centauri in 100 years so they can send back a signal."
SSB: "What kind of food will they eat? You can't just ignore that."

3. ### DaveC426913Valued Senior Member

Messages:
18,673
They'll eat carrots. Does that affect the radio signal they send back?

5. ### sideshowbobSorry, wrong number.Valued Senior Member

Messages:
7,057
So when the student doesn't understand, blame the student.

7. ### DaveC426913Valued Senior Member

Messages:
18,673
OK, that's an admission that you're not understanding. I'll accept that.

As I've said: the practicalities of such an experiment don't matter.

Let me recap one more time:

Dave: "There is nothing objective about the human sequential values A,2,3,...K. It's an arbitrary measure of order.
You could just as easily decide that it is more logical to consider order based on weight: how closely they are sorted by heaviest (most ink) to lightest."

W4U:
"...you cannot randomly unshuffle a deck of cards"

Dave:
"Yes you can.
1] It would take a very long time, true, but there is no reason why it wouldn't happen.

2] It is only due to a matter of scale. I proved this by trying it with a smaller deck: just the aces. I was able to shuffle the aces back to order with no more than 4 shuffles (OK, they weren't perfectly random shuffles, but there's no law saying that disorder must be caused by random processes).

Consider dropping a sequence of A-10 cards from a 20 yard height in still air. The cards will be disordered by the fall, but the chance that they land heaviest card first and lightest card last is considerably better than random."

--

So, the cards are ostensibly getting shuffled, yet a fixed property of the cards (their individual mass) may result in them reaching a roughly ordered state by biasing the shuffle.

As you can see, it is only the principle we are talking about. All the questions about how they're dropped are immaterial. You can assume the ideal case that proves the point.

Last edited: May 28, 2019
8. ### sideshowbobSorry, wrong number.Valued Senior Member

Messages:
7,057
That's a poor analogy. The time it takes a card to fall is directly related to the path of the fall - but the path of the fall is not necessarily directly related to the weight or the surface area.

9. ### sideshowbobSorry, wrong number.Valued Senior Member

Messages:
7,057
It's an admission that you don't think I understand. You're giving me a failing grade because you've failed to get your point across.

10. ### DaveC426913Valued Senior Member

Messages:
18,673
I have stated the point explicitly multiple times. Your responses indicate that you have not even read it. I'll try again:

Since it is a thought experiment, the practicalities of performing such an experiment do not affect the principles:

1] Of two cards with the same surface area, the one that is 3% heavier has a statistically more likely probability of landing first.

2] One could, in theory, construct a shuffler that, to a degree better than chance, would sort a number of cards by weight.

Claiming the path will be affected does not invalidate either of the above assertions (even if it might present a challenge to factor out of such a practical experiment).

Last edited: May 28, 2019
11. ### sideshowbobSorry, wrong number.Valued Senior Member

Messages:
7,057
And you have neglected to answer my question multiple times: Do you propose the drop the cards individually or en masse?

12. ### DaveC426913Valued Senior Member

Messages:
18,673
I do not propose the experiment. I simply propose the principle. See #167, above.

What you are asking about is the implementation, and how one might eliminate confounding factors. Not my concern. The principles stand independent of practicalities.

13. ### sideshowbobSorry, wrong number.Valued Senior Member

Messages:
7,057

Why should anybody consider a thought experiment that doesn't even pretend to be connected to reality?

14. ### DaveC426913Valued Senior Member

Messages:
18,673
I do not refuse to answer.

I have proposed no experiment. I have nothing to say about how it might be implemented.

You are being needlessly contrariwise.

15. ### DaveC426913Valued Senior Member

Messages:
18,673
Your assertion is that, since we have not actually described the implementation the experiment, we cannot discuss the principle?

In a discussion about interstellar communications latency:
D: "Assume a ship that can get to A.Centauri and send back a signal."
SSB: "If you can't tell me what they'll be eating, it's not connected to reality."

16. ### wegsMatter and Pixie DustValued Senior Member

Messages:
9,232
I think it's safe to say, in summary that a fresh pack of cards, taken out of the box (unshuffled) would have the lowest entropy ...and any other choices after the deck is randomly shuffled, cards spread out, or dropped on the floor making a mess - would be nearing the highest entropy, possible.

Heavier cards vs lighter cards could matter if that is the ''state'' that you wish to assess. But,once the cards go through a series of random shuffles, the disorder increases. I don't see why it matters how we got there.

17. ### sideshowbobSorry, wrong number.Valued Senior Member

Messages:
7,057
Then answer: Do you really not understand that the aerodynamics are completely different depending on how the experiment is conducted? You can "think" away every objection but you're just making your whole thought irrelevant.

18. ### sideshowbobSorry, wrong number.Valued Senior Member

Messages:
7,057
My suggestion is that the "principle" is just a fantasy unless it has some anchor in reality - or even just a tiny willingness to consider the possibility of testing it in reality.

19. ### DaveC426913Valued Senior Member

Messages:
18,673
I do. It does not affect the principles, as outlined in post 167.

So let me get this straight: since no system can truly be said to have zero entropy, then experiments that test for entropy will raise objections from you. That means, as far as you're concerned this entire topic about entropy, starting from post 1, is utterly meaningless, because you will always be able to raise an objection to any practical experiment.

20. ### DaveC426913Valued Senior Member

Messages:
18,673
It is anchored in reality. You being unable to think of a way of eliminating spurious variables does not divorce it from reality.

Here are my assertions:

1] Of two cards with the same surface area, the one that is 3% heavier has a statistically more likely probability of landing first.

2] One could, in theory, construct a shuffler that, to a degree better than chance, would sort a number of cards by weight.

Nothing of what you've said invalidates them. Though I will grant the experiment may have practical challenges.

I am absolutely willing to have it tested it in reality. Let me know how it goes. Let me know if my assertions are upheld.

21. ### sideshowbobSorry, wrong number.Valued Senior Member

Messages:
7,057
No. I'm saying that a "thought experiment" that refuses to consider any objections is an empty contrivance.

22. ### sideshowbobSorry, wrong number.Valued Senior Member

Messages:
7,057
Then how do want it tested? One card at a time or en masse? Do you expect to get the same result from both?

23. ### DaveC426913Valued Senior Member

Messages:
18,673
Only if you take it as granted that the initial state is defined as lowest entropy.

Indeed.