That dude is a legend in his own mind.Yes it does, clearly and completely. Your statement:No, it doesn't. T
"Of course it is expanding into space"
...is utterly incorrect, and the article is an attempt to explain why it is incorrect.
This misconception on your part is the source of your errors and of your nonsensical queries, such as to ask how matter moves "perpendicularly to the direction of the explosion".
That query is nonsensical. You think it isn't. And this is due to the fundamental error I have described.
I think i have exhausted all resources at my disposal that would help you understand why you are making a fundamental error. I encourage to to keep reading up on the topic and to ask others. Prehaps you will come to understand your error.
What is clear is you are not capable of thinking in complex enough ways to carry on a conversation about a subject that is far beyond your comprehension.
Is it fair enough for me to assume that you have a science or engineering background?