# Q: What is the entropy of nothing?

Mathematician: In physics, entropy relates to the number of states that a system can be in. If a system actually contained absolutely nothing, then (quantum mechanical considerations aside), it would only have one state, and therefore would have 0 entropy (there would be no uncertainty at all about what state it is in). In reality though, things are more complex. Particles and anti-particles will pop into existence in pairs in empty space.

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### 6 Responses to Q: What is the entropy of nothing?

1. Anonymous says:

So what is the entropy of a vacuum?

2. Bo Brymer says:

0 entropy holds either beginning or end of existance which contains zero of a systems
portion to exist at all. 0 entropy maintains purpose for 1 entropy to defer and be measured. Without 0 entropy 1 would not seperate states of thermodynamics.

3. christian smith says:

where do the particles that pop into empty space come from? and why those particles? happy to donate a few bucks to you guys.

4. The Physicist says:

That’s very profound.
They don’t come from anywhere. That is; you don’t need some kind of source for them from “somewhere else”. When new particles are created they have to obey a (surprisingly large) set of conservation laws. Things like (but not limited to);
-If the new particle has charge, then you also have to create another particle with the opposite charge.
-If you create a particle made of matter, you have to create an anti-matter particle.
-Energy is conserved, so you can’t just “declare” particles into being, you need to spend some energy.
What is not conserved is particle number. There are no physical laws preventing new particles from forming, or old particles being destroyed. In fact, it’s an integral part of how the universe works!
Some particles are randomly generated more often than others. The probability of a new particle being of some type “A” is proportional to the number of states that “A” can be in, which is exactly how you go about maximizing entropy. So, you can write off the selection of new particles as just another attempt by the universe to increase entropy.

5. Scooby Poo says:

If the universe is expanding and has a boundary surface and a super massive black hole were suddenly eliminated (suppose for arguments sake it is absolutely eliminated in terms of mass and or energy) how long would the effect of it’s elimination reach the boundary surface? If the Black hole were a light year from the boundary, would it take a year to say affect the geometrical boundary of the universe?

This is a thought experiment of course…as it disobeys the laws of thermodynamics. still, it begs the question of how fast gravity would travel.

6. Angel says:

@Scooby Poo:

That would really depend on the size of the black hole, or maybe even on what kind of black hole it is.