[Closed] Entropy

Personally I'm more concerned that Craig is no longer the manager of the Kidd (gone back to Scotland). It's not the same anymore. 🙁

Get on Skypes, innit! 🙄

Wait until you get to this weeks episode then. We're all made out of dead stars and he illustrates this using bubbles.

Is this Facebook now, is it? 😆

Personally, I thought The Truman Show was a great idea for a film, ruined by Jim Carey and just not done propply really.

My wife thought we had achieved a state of entropy, until I explained to her it was only because she did not understand the concept of a floor shelf...

yes wallop!

she did not understand the concept of a floor shelf...

The correct name for this is the "dog shelf."

HTH.

did someone say Cox? Brian Cox? <swoon> 😳 nom nom nom

Girl loves the Cox.

Badum tish

cheers, how do I unscrew my facebook? do I care?

I'm not a Brian Cox fan...no particular reason, I just don't really like him.

As a chemistry student I vaguely understand Entropy. My friend dropped his box of staples (which were all neatly organised in the box), and then he couldn't get them back in - my response was "that's entropy for you" we were chuckling away to ourselves for a while after that 😛

Second law of thermodynamics (or is it the third????) takes me back to chemistry lectures and trying to understand what the physical chemistry lecturer was on about.....

Something about his delivery makes me turn over which is a shame as I find the subject matter very interesting.

So the law of entropy, ie that entropy always increases, signals the "arrow of time".

So - in the early universe, when clouds of particles were swirling around and forming into lumps, was time running backwards? Entropy was [i]decreasing[/i] as things formed into stars, planets, other lumps.

no thats different

The ususal example is a jam jar with a layer of slat and a layer of pepper in it.However much you shake it the salt an pepper will not seperate out, thus the system has gained entropy.

However, add in some gravity and very small oscilations and the layers will settle out again, how can that be?

Well, youve got enthalpy (energy) as well to considder.

In order to seperate out the two layers you had to convert a lot of energy from chemical, to mechanical to gravitational potential and heat. So the system has reached its lowest gravitational potential energy and its entropy appears to have lowered, but you've taken lots of long chained fats and carbohydrates and turned them into CO2 and H2O, more molecules = more entropy.

Thus the formation of planets follows the same principle, you've decreaced the entropy slightly but collecing everythign into nice lumps, but you've also added a lot of entropy to the system elswhere. One step back, 2 steps foreward.

As much as I enjoy Dr Cox and his Wonders serieseseses I do find he presents things in the way I imagine a cult leader would.

- Softly spoken
- Pleasant permanent half-smile
- Explains that everything is wonderful and amazing

I'm fully expecting a trigger word to have been introduced and that one Sunday evening there'll be a mass suicide as he instructs us all to become one with the universe once more...

I can't get enough of him, he's a great presenter of difficult subjects. I wish I was as good.

So - in the early universe, when clouds of particles were swirling around and forming into lumps, was time running backwards? Entropy was decreasing as things formed into stars, planets, other lumps.

Entropy is not a law in isolation, for example Energy will always tend to a minimum state which can lead to a decrease in Entropy, for example in chemistry the crystallisation process where compounds will solidify out of solution when said solution cools or becomes more concentrated.

Its not "erosion", its simply an accelerated increase in entropy.

- Softly spoken
- Pleasant permanent half-smile
- Explains that everything is wonderful and amazing

Totally agree I bet he would be even worse in real life. Im always suspicious of people with out obviously personality defects I just assume they most have one mega-large defect hidden away.

The thing to remember about the second law is that it applies to CLOSED systems. And most real world examples are not really closed.