Why did entropy decrease after the big bang?

AI Thread Summary
The discussion explores the decrease in entropy after the Big Bang, highlighting that the early universe was filled with uniform energy, as evidenced by cosmic microwave background radiation. It argues that uniform matter distribution is unstable under gravitational influence, leading to higher entropy states where matter clumps together, such as in black holes. The conversation emphasizes that while the early universe had low entropy, it has increased over time, aligning with the second law of thermodynamics. Additionally, it suggests that the relationship between gravity, space, and time may influence entropy levels, with denser configurations leading to higher entropy. Overall, the formation of stars and their heat generation are seen as crucial for increasing entropy in the universe.
pointlesslife
Messages
4
Reaction score
0
According to the big bang model, the very early universe was at one time filled with energy. The cosmic microwave background radiation shows that the energy of the universe was very uniform. The deviation of energy in the famous CMB radiation picture taken was on average just 1 in 100,000 the average temperature.

So why did uniformity decrease as galaxies were formed in the very early universe? Does this contradict the 2nd law of thermodynamics?
 
Science news on Phys.org
Contrary to popular opinion, uniformly distributed matter is unstable in presence of gravitation and is actually the least likely state with very low entropy. Most probable high-entropy states are those where matter is all lumped together in massive objects, culminating in the creation of black holes.
 
Delta Kilo said:
Contrary to popular opinion, uniformly distributed matter is unstable in presence of gravitation and is actually the least likely state with very low entropy. Most probable high-entropy states are those where matter is all lumped together in massive objects, culminating in the creation of black holes.

Now that I think about it, gravitation does turn the tables. It would be impossibly improbable for objects such as planets/stars to uniformly distribute back in space again. So yeah, I would agree that entropy of the early universe was very low and has only increased since so the 2nd law of thermodynamics isn't wrong.
 
Consider that all matter and energy in the early universe was closer together than it is now. But at the same time moving away from the center.

Entropy might have a dependence on the curve of space/time, as the less curve the more entropy. So matter and energy that are not as close together have a lower gravity and thus appear to the observer to be unstable and a low entropy. But the higher density space/time with the matter and energy closer together has a higher entropy. It could be then that distance has a lot to do with it along with gravity and space/time as factors. In higher energy states we find that space/time can separate into space and time.

Your automotive engine for example is density packed with metals and uses high energy or heat from explosions of gasoline to push pistons and give you the ability to turn the wheels. In this high energy state, we have high energy but we still have Earth's gravity as well as high entropy. Which is why your fuel efficiency goes down so heat is a form of energy that has to do with it.

Then I'd say that stars generate heat to cause higher entropy and in the early universe there wasn't much heat as stars didn't form yet and provide the heat and higher gravity for higher entropy.

Just a theory, I could be wrong.
 
I need to calculate the amount of water condensed from a DX cooling coil per hour given the size of the expansion coil (the total condensing surface area), the incoming air temperature, the amount of air flow from the fan, the BTU capacity of the compressor and the incoming air humidity. There are lots of condenser calculators around but they all need the air flow and incoming and outgoing humidity and then give a total volume of condensed water but I need more than that. The size of the...
I was watching a Khan Academy video on entropy called: Reconciling thermodynamic and state definitions of entropy. So in the video it says: Let's say I have a container. And in that container, I have gas particles and they're bouncing around like gas particles tend to do, creating some pressure on the container of a certain volume. And let's say I have n particles. Now, each of these particles could be in x different states. Now, if each of them can be in x different states, how many total...
Thread 'Why work is PdV and not (P+dP)dV in an isothermal process?'
Let's say we have a cylinder of volume V1 with a frictionless movable piston and some gas trapped inside with pressure P1 and temperature T1. On top of the piston lay some small pebbles that add weight and essentially create the pressure P1. Also the system is inside a reservoir of water that keeps its temperature constant at T1. The system is in equilibrium at V1, P1, T1. Now let's say i put another very small pebble on top of the piston (0,00001kg) and after some seconds the system...
Back
Top