[Serious] Is the Past Real?

[Jehanne]

Exactly. It has a truth value that *could* be determined.

Now, for quantum events, that is not the case.

So, suppose that I pick a single uranium atom. ALL we have is probabilities for when it will decay. We do NOT have, even in principle, a way to determine when it will decay. So the statement that it will decay tomorrow at noon is neither true nor false.

But I can go further. Suppose I have isolated a uranium atom last week. I have neither looked at it nor had any detector consider it. Is the statement that it decayed two days ago at noon one that has a truth value?

I would say not, just as the statement that it will decay tomorrow at noon does not.

I think we need to separate what is in principle unknowable to us, as opposed to what is in principle not knowable at all, when we say whether the past is real.    It seems to me If it is in principle knowable to someone somewhere, then it is real.   It is just that we don’t know it and can’t know it.  Chaucer’s last meal is in principle knowable to someone, even if we hypothesize that some quantum event forever obscures it from us and anyone with whom we in principle can communicate. 

It seems to be that the principle of indestructibility of information says all past must be knowable to someone somewhere, so it is real.

What if Chaucer dined alone before his death?