The following is not a question: Can something come from nothing?

[Alex K]

What happens when you switch on a light?

Where do the photons come from?

Did they exist before you switched on the light?

Photons are created when an electron changes its energy state but when you switch off the light and the electron falls back the photon isn't sucked back in.

In effect - the photon is created out of nothing.

I thank you.

There are different forms of energy, what you describe is merely the conversion from one type to another. In the presence of spacetime.

[Angrboda]

Your definition of entropy and the arrow of time seems circular. Water falls because there are more possible states it can be after than before, yet this is just the definition of the arrow of time itself, so you haven't really explained the arrow of time, simply shown something that occurs if you assume a specific arrow of time. (Which may be violated, e.g. fluctuation theorem and time-reversal interpretation of QM.)

The arrow of time is a result by entropy itself. The laws of physics are time-independent, which is why we can "retrodict" things with the laws of physics. What we call "past" and "future" are simply a result of a recognition of the difference between 2 states of affairs wherein one state has less entropy than another. The reason for this is because is is the case that there are more ways to be in a disordered state than an ordered state. There's no circularity there.

The problem is explaining why entropy should increase rather than decrease. By using the terms 'increase' and 'decrease' with regard to entropy, you're already appealing to a concept of time that has a direction, thus the circularity.

[max-greece]

What happens when you switch on a light?

Where do the photons come from?

Did they exist before you switched on the light?

Photons are created when an electron changes its energy state but when you switch off the light and the electron falls back the photon isn't sucked back in.

In effect - the photon is created out of nothing.

I thank you.

There are different forms of energy, what you describe is merely the conversion from one type to another. In the presence of spacetime.

Except a photon isn't merely energy. It an elementary particle which carries energy proportional to the radiation frequency.

I'd give you a duality between energy and a particle if you like - but I don't think you can get away with just energy.

[John V]

Except a photon isn't merely energy. It an elementary particle which carries energy proportional to the radiation frequency.

I'd give you a duality between energy and a particle if you like - but I don't think you can get away with just energy.

IMO the main point is that the photon came from an existing electron.

The other point is that, more generally, space-time is itself something, and so it's impossible to have nothing in our universe.

[tor]

Except a photon isn't merely energy. It an elementary particle which carries energy proportional to the radiation frequency.

I'd give you a duality between energy and a particle if you like - but I don't think you can get away with just energy.

IMO the main point is that the photon came from an existing electron.

The other point is that, more generally, space-time is itself something, and so it's impossible to have nothing in our universe.

Where is it possible to have nothing?

[Jackalope]

Where is it possible to have nothing?

Nowhere, of course.

[John V]

Where is it possible to have nothing?

That's a nonsensical question.

[max-greece]

Except a photon isn't merely energy. It an elementary particle which carries energy proportional to the radiation frequency.

I'd give you a duality between energy and a particle if you like - but I don't think you can get away with just energy.

IMO the main point is that the photon came from an existing electron.

The other point is that, more generally, space-time is itself something, and so it's impossible to have nothing in our universe.

Actually, specifically, the photon did not come from an existing electron. The electron lost nothing in the production of the photon.

---

Where is it possible to have nothing?

That's a nonsensical question.

Actually, again, it isn't. There is no evidence that "nothing" - depending on how we want to define that, can actually exist.

According to Quantum Theory nothing (nothingness to be clear) is unstable. It's fully possible that true nothing cannot exist.

Things get further confused if time exists only as part of a universe. With no time everything happens instantaneously so nothingness wouldn't even exist for the smallest unit of time possible.

[tor]

alpha what did god make universe from?

[coldwx]

Except a photon isn't merely energy. It an elementary particle which carries energy proportional to the radiation frequency.

I'd give you a duality between energy and a particle if you like - but I don't think you can get away with just energy.

IMO the main point is that the photon came from an existing electron.

The other point is that, more generally, space-time is itself something, and so it's impossible to have nothing in our universe.

Just a point of clarification for me, and I apologize if you explained it earlier and I missed it, but is your claim that god created the universe from nothing? It seems this is a common claim that I hear yet then an argument is made that nothing can not exist. This seems to be a contradiction. Or is god the something that exists, so therefore there was something?