Exploring Entropy: How is the Universe Increasing in Disorder?

In summary, the statement "an increase in the entropy of the system will be exactly equal to the entropy decrease of the surroundings. So the net change in the entropy of the system and its surroundings is zero" is straight of a kaplan physics review book for the MCAT. It didn't make sense to me because it does imply a conservation law, and then it confused me even more on the concept of entropy...if the equation for change in entropy is delta S = Q/T, if the environment loses heat to the system, wouldn't the environment have a negative delta S (and the system positive)? Does that mean entropy is decreased in the environment, and increased by the same amount by the system?
  • #1
ninjarawr
12
0
For example, an increase in the entropy of the system will be exactly equal to the entropy decrease of the surroundings. So the net change in the entropy of the system and its surroundings is zero.

Putting this in perspective to all the systems and environments in our universe, how is the universe always increasing in entropy?


Thanks in advance!

ninjarawr
 
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  • #2
I'm not really sure the if the entropy of a system increases, the entropy of the surroundings will decrease. There's no conservation of entropy-law. If you have a closed system, it's entropy has nothing to do with the surroundings.
 
  • #3
ninjarawr said:
For example, an increase in the entropy of the system will be exactly equal to the entropy decrease of the surroundings.

Oh, really? Prove it :smile:
 
  • #4
I think what may have confused you is that if you look at a 'non-closed' system you can observe an entropy decrease, but this means that entropy somewhere else was increased.
So entropy is still increasing overall.

Perhaps you read something like that and generalized it to a conservation law..
However, it doesn't work the other way around. So an entropy increase does not have to accompany an entropy decrease.
 
  • #5
Gear.0 said:
I think what may have confused you is that if you look at a 'non-closed' system you can observe an entropy decrease, but this means that entropy somewhere else was increased.
So entropy is still increasing overall.

Perhaps you read something like that and generalized it to a conservation law..
However, it doesn't work the other way around. So an entropy increase does not have to accompany an entropy decrease.

The statement "an increase in the entropy of the system will be exactly equal to the entropy decrease of the surroundings. So the net change in the entropy of the system and its surroundings is zero" is straight of a kaplan physics review book for the MCAT. It didn't make sense to me because it does imply a conservation law, and then it confused me even more on the concept of entropy...if the equation for change in entropy is delta S = Q/T, if the environment loses heat to the system, wouldn't the environment have a negative delta S (and the system positive)? Does that mean entropy is decreased in the environment, and increased by the same amount by the system?
 
  • #6
Fom Wikipwdia: "In systems held at constant temperature, the change in entropy, ΔS, is given by the equation

[tex] \Delta S = \frac{Q}{T} [/tex],

where Q is the amount of heat absorbed by the system in an isothermal and reversible process in which the system goes from one state to another, and T is the absolute temperature at which the process is occurring."

ehild
 

1. What is entropy?

Entropy is a measure of the disorder or randomness in a system. In simple terms, it represents the amount of energy that is no longer available to do work. As a system evolves, it tends to move towards a state of higher entropy, or greater disorder.

2. How does entropy relate to the universe?

The concept of entropy is closely tied to the second law of thermodynamics, which states that the total entropy of a closed system will always increase over time. This means that the universe as a whole is constantly moving towards a state of maximum disorder.

3. Can entropy be reversed?

While individual systems may experience a temporary decrease in entropy, the overall trend is towards higher entropy. This is due to the fact that in order to decrease entropy in one part of a system, there must be an even greater increase in entropy in another part of the system.

4. How does entropy play a role in the formation of stars and galaxies?

The increase in entropy over time has allowed for the formation of stars and galaxies. As matter becomes more spread out and disordered, gravity is able to pull it together to form larger structures. This process is known as gravitational collapse and is essential for the formation of stars and galaxies.

5. Is there a limit to how much entropy the universe can have?

Currently, there is no known limit to the amount of entropy in the universe. However, some theories suggest that as the universe continues to expand, it will eventually reach a state of maximum entropy, known as the "heat death" of the universe. This is a point at which all energy is evenly distributed and no work can be done, leading to a state of complete disorder.

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