hypothetical question

[nishant1911]

a mixture of carbon, oxygen, nitrogen, phosphorus and many such elements was exposed to sunlight,heat and pressure for billions of years, how come after all these years it started manipulating other matter and build spaceships and cars?

in other words , how did entropy of the system started decreasing instead of increasing after a certain point?

 

[Earthling]

Entropy is not decreasing. Energy comes from the sun, entropy increases as it burns through its fuel.

 

[warpus]

My friend Steve is responsible for all of this.

 

[suiraclaw]

[edit] Biophysics

Biophysicists have also commented on the nature and qualities of life forms—notably that they function on negative entropy.[25][26] In more detail, according to physicists such as John Bernal, Erwin Schrödinger, Eugene Wigner, and John Avery, life is a member of the class of phenomena which are open or continuous systems able to decrease their internal entropy at the expense of substances or free energy taken in from the environment and subsequently rejected in a degraded form (see: entropy and life).[27][28][29]

Above quote is from the wikipedia page about "Life".

This page details more about it:
http://en.wikipedia.org/wiki/Entropy_and_life

 

[Neonanocyborgasm]

in other words , how did entropy of the system started decreasing instead of increasing after a certain point?

In other words, how did you find the time to witness by casting doubts on cosmology and evolution?

 

[Deego3]

Whenever the first cell developed the ability to use active transport, which is the movement of molecules against defusion. They could then put molecules in order. However, they have to use energy to put molecules in order. Therfore, entropy either increases or remains the same.

 

[warpus]

Entropy never increases in ISOLATED systems.

The Earth is not an isolated system; there is energy being introduced from the outside.

 

[sophie]

I'm trying to understand how this is a hypothetic question...

 

[nishant1911]

Entropy never increases in ISOLATED systems.

i was told the exact opposite of this, mind enlightening me?

The Earth is not an isolated system; there is energy being introduced from the outside.

true, but energy tends to increase the entropy, while what we see is the reverse action taking place(biomass is ordered) ...so what accounts for it?

 

[Bill3000]

i was told the exact opposite of this, mind enlightening me?

Second law of thermodynamics is only true in isolated systems, e.g. systems with no exchange in particles, mass, or energy to other systems. Entropy can decrease locally as long as the net entropy is >=0 in the full isolated system.

For example, a refrigerator decreases entropy, (colder = less entropy) but the entropy decrease is more than offset by the heat loss by the refrigerant.

true, but energy tends to increase the entropy, while what we see is the reverse action taking place(biomass is ordered) ...so what accounts for it?

It's way more than offset by the generation of heat by metabolism.

 

[nishant1911]

It's way more than offset by the generation of heat by metabolism.

heat is a 'side effect' of metabolism and is usually much less than work obtained.so what if the work generated by metabolism was used to decrease entropy or make more ordered things? wouldn't that be an overall decrease?

 

[nishant1911]

I'm trying to understand how this is a hypothetic question...

so op wasn't hypothetical enough?

suppose we humans develop nanobots that can self -replicate and they go out of control
(a doomsday scenario)
they manipulate matter and turn it into ordered form. the process continues till whole universe turns into 'grey goo'. is that a violation of second law?

 

[sophie]

so op wasn't hypothetical enough?

suppose we humans develop nanobots that can self -replicate and they go out of control
(a doomsday scenario)
they manipulate matter and turn it into ordered form. the process continues till whole universe turns into 'grey goo'. is that a violation of second law?

No. I mean if you're going to make a thread saying you have no idea how science works, you might as well come out and say it rather than doing it through some roundabout pseudo-hypothetical.

 

[Neonanocyborgasm]

That nishant has deliberately avoided responding to my accusation that he is witnessing should be proof that he is doing just that. Nishant is witnessing for his religion, most likely evangelical Christianity, by casting doubts on "godless" science, such as cosmology and evolution. For many, these sciences are an attack on their articles of faith, and they see it as their duty to discredit them, both to demonstrate their piety, and to show up disbelievers so that they have no excuse when judgement day comes. It doesn't matter that nishant is deliberately hiding this fact, because to people like him, lying is ok if it is done in the name of their god.

Moderator Action: Discuss the post, not the poster.
Please read the forum rules: http://forums.civfanatics.com/showthread.php?t=422889

 

[Bill3000]

heat is a 'side effect' of metabolism and is usually much less than work obtained.so what if the work generated by metabolism was used to decrease entropy or make more ordered things? wouldn't that be an overall decrease?

What? No. Metabolism doesn't have close to 100% efficiency. For example, aerobic respiration is about 40% efficient (energy gained in the form of ATP is 40% of the potential energy of glucose; the rest is released heat) If metabolism violated the second law of thermodynamics, that would mean that it could be 100% efficient. And again, the second law of thermodynamics doesn't prevent the local decrease in entropy.

suppose we humans develop nanobots that can self -replicate and they go out of control
(a doomsday scenario)
they manipulate matter and turn it into ordered form. the process continues till whole universe turns into 'grey goo'. is that a violation of second law?

Those nanobots would need energy sources and eventually would only be left with heat as an energy source, and thus would be constrained by the second law of thermodynamics. You're severely underestimating the amount of entropy contained in thermal energy.

 

[bernie14]

i am not a physicist, just had to take some classes a long time ago, but in a biology class (i took a long long time ago) i recalled that there was a theory that had to do with the primordial soup, a "reducing" atmosphere (as opposed to oxidating) and some lightning and POOF!!! there may be some sort of life....i wikied it...so iirc, it goes something like this

 

[Bill3000]

That's not actually an answer to his question, which isn't how it came to be, but why is it that order could be spontaneously produced.

It's a misleading question because entropy can easily locally decrease in non-isolated systems - as I said earlier, see the refrigerator, which locally decreases entropy within the refrigerator. However, the refrigerator also produces additional heat (fridges require a power source!) which way more than offsets the difference in entropy. The heat moves outside the fridge. Here's a link explaining this.

The entropy in life is rather miniscule compared to thermal energy anyway. Living organisms preserve their internal order by taking from their surroundings free energy, in the form of nutrients or sunlight, and returning to their surroundings an equal amount of energy as heat and entropy.

 

[warpus]

i was told the exact opposite of this, mind enlightening me?

Whoops.. I meant the exact opposite, you're right. *blush*

 

[Japanrocks12]

That nishant has deliberately avoided responding to my accusation that he is witnessing should be proof that he is doing just that. Nishant is witnessing for his religion, most likely evangelical Christianity, by casting doubts on "godless" science, such as cosmology and evolution. For many, these sciences are an attack on their articles of faith, and they see it as their duty to discredit them, both to demonstrate their piety, and to show up disbelievers so that they have no excuse when judgement day comes. It doesn't matter that nishant is deliberately hiding this fact, because to people like him, lying is ok if it is done in the name of their god.

Moderator Action: Discuss the post, not the poster.
Please read the forum rules: http://forums.civfanatics.com/showthread.php?t=422889

Dude, his name is Nishant, he's probably Indian. Something on the order of 1% of Indians are Christian.

 

[NetGear]

While we're on topic,

"Air conditioners, how do they work?"

"F-ing magic".