i am curious what you mean by this?
More or less exactly what I said.
Suppose you could write down three lists:
(1) All the "information" possible about A.
(2) All the "information" possible about B.
(3) All the "information" possible about A and B.
Classically, (3) is formed simply by concatenating (1) and (2).
But quantum mechanically, (3) is longer than that. The amount of "information" in the sum of the parts is greater than the sum of the information in the individual parts. (In some sense, the information in the sum of the parts is the
product of the information in the individual parts)
Hrm. Maybe this example is useful and not too misleading.
Suppose you have a (possibly biased) die in front of you. It takes five numbers to describe the die completely: the odds of rolling a 1, a 2, a 3, a 4, and a 5. (From which you can figure out the odds of rolling a 6)
Suppose you have two dice. How many numbers do you need to describe them?
Classically speaking, you only need 10 numbers: 5 for each die. (From which you can figure out the odds for each of the 36 possible outcomes, because classical dice are statistically independent)
But quantum mechanically speaking, you really need 35 numbers. (Because quantum mechanical dice don't need to be statistically independent)
The extra information comes from entanglement -- when you consider "A and B", you not only need to know about "A" and about "B", but you also need to know about the manner in which they may or may not be entangled.
Of course, if you have reason to believe the dice are not entangled, then you only need 10 numbers to describe a pair of quantum mechanical dice.