You can't see me but I'm here. I'm everywhere and although I'm weak, I can make even the smallest object deadly with enough space. I can even bend light itself. What am I?

For me time never passes, but yet the same instant that I'm born, I die

Used in math but not a number. I can be golden, inverse, or direct. I remain constant when my parts change size.

Present when you speak but never when you're silent. Broken without being touched, and kept without being held. Given freely but once broken, nearly impossible to repair. Kings and beggars possess me equally, yet it's measured differently for each.

I ate the one after the next - who was three by three, The count of the rainbow's arcs, The steps on music's marks.