No Witnesses

But is fusion the only mechanism by which stars emit radiation and generate heat? Could it be possible that some stars generate heat simply by friction between gases cause by gravity?

So, it impossible to generate the heat the sun does with the use of fusion?

I meant without. But I am actually on topic. It was stated that you don't have to directly observe fusion at the center of the sun to know it is occurring. The idea is that we can infer based on the evidence. It is actually the neutrino emission that is the dead ringer for fusion. Without that, I don't know that we can know that fusion is going on for sure by inference. I was trying to show that there are other possibilities besides the one that was said to be "obvious" by inference. I was trying to figure out if it was possible for a star with the mass and size of our sun to generate the heat it does without the help of fusion. I am not sure my question has been adequately answered. The point I am make that has to do with the topic here is that there are often other possibilities that can be inferred from the evidence when it is impossible to take direct measurements. Just because a conclusion can be reached by inference, doesn't mean it is the correct inference.

This was what I was looking for.

Are you saying that seals and walruses used to be otters and beavers? Are you saying that otters and beavers will one day be seals and walruses?Edited by foreveryoung, : No reason given.

Well, that is what you communicated to me. That is what I got out of what you said. If that is not what you meant, what did you mean?