B Questions regarding energy in the universe

As I am watching the current season of How the Universe Works, I am a bit confused when listening to physicists talking about energy as if it was a thing.

The way I understand it, energy doesn't exist by itself, but is rather the result of interactions involving matter.

Energy is released, captured, released and so on.

For example, nuclear reactions in the sun release energy, some of which is captured by tree leaves, that will later on be used as fossil fuel, thus releasing energy...

But there is no energy readily available as such, in the same way that there is no wind without air and a certain set of conditions.

Having said all that, what does it mean to say that the Big Bang was a massive release of energy previously concentrated in a small point?

Or what does it mean to say that dark energy is making the universe expand?

What energy? How can there be energy without a source?

Why and how would the release of energy associated with the Big Bang create heat, and what would be heated in the first place, since there was nothing but energy to begin with?

Energy is not cold or hot, or is it?

How can energy be compressed or expand?

One can do that with air, for example, because it is matter, but it seems meaningless to talk about volume when it comes to energy

Assuming that dark energy would be part of the energy released with the Big Bang, how could it have been preserved as such for billions of years, without being absorbed by the matter around it?

So many questions...
 
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The way I understand it, energy doesn't exist by itself, but is rather the result of interactions involving matter.
correct.
... what does it mean to say that the Big Bang was a massive release of energy previously concentrated in a small point?
It means that you are listening to a pop-science presentation that is entertainment and has little to do with actual science.

Or what does it mean to say that dark energy is making the universe expand?
SOMETHING is making the universe expand. We don't know what it is so well call it "dark energy" just to have a name to hang on it.
 
Are you implying that the scientists who actively participate in this "pop science presentation" are charlatans who shouldn't be trusted?

And if so, what is the answer regarding the Big Bang? Was it not energy, but something else that was involved? Or do we simply don't know?
 
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Are you implying that the scientists who actively participate in this "pop science presentation" are charlatans who shouldn't be trusted?
Possibly they are not charlatans but they absolutely are not to be trusted when appearing in these entertainment presentations. They will say things that they KNOW are simplifications to the point of being wrong. It's ENTERTAINMENT, not science.
 

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