I'm wondering, now that the universe has expanded and is now pretty much flat, can any experiment we do tell us what might have happened during the Big Bang, when the universe was still small and tightly curved? It doesn't sound like the same situation. The results we get today travel meters or inches to the detectors, which is still very large compared to the very early universe. Would the same things result in a universe that is tightly curled up? If not, how far back can we go before we are no longer comparing apples to apples? Thanks.