7raindrops
What was that arch that sirius fell through?
why doesn't everyone just take the truth serum when put in front of the ministry of magic?
It contains the proverbial Veil of Death, also known as the Mortal Coil - as in, "For in that sleep of death/what dreams may come/when we have shuffled off this mortal coil/must give us pause." Actually, here's JKR's view on it, from an interview she did in 2008:
"JKR: It's the divide between life and death. I tried to do a nod to that in The Tale of Three Brothers - she was separate from them as though through a veil. You can't go back if you pass through that veil, you cannot come back. Or you can't come back in any form that will make either person happy anyway.
But when they surround that veil [in Order of the Phoenix], I was trying to show that depending on their degree of skepticism or belief about what lay beyond - because Luna, of course, is a very skeptical character. Luna believes firmly in an afterlife. She's very clear on that. And she feels them speaking or hears them speaking much more clearly than Harry does. This is the idea of faith. Harry thinks he can hear them; he's drawn on. But Harry's had a life that has been so imbued with death that he now has an uncharacteristically strong curiosity about the afterlife, especially for a boy of 15, as he is in Phoenix. Ron's just scared, as I think Ron would be - he just knows this is something he doesn't want to dabble with. Hermione, hyper-rational Hermione - 'can't hear anything, get away from the Veil.' So if you walk through the veil, you're dead. You're dead. What you find on the other side, well, that's the question.
Do I believe you go on? Yes, I do believe you go on. I do believe in an afterlife, although I'm absolutely doubt-ridden and always have been but there you are."