The term was coined in 2009, when writer Fiona Broome realized her detailed memory of the death of Nelson Mandela was impossible. In recent years, there's been a growing interest in the so-called Mandela effect, the phenomenon of a collective but incorrect memory, (or, as conspiracy theorists allege, a memory of events from an alternate reality). It's easy to remember things that didn't happen at all. That day - especially those earliest hours of it - has been chronicled, packaged, interpreted and misinterpreted so exhaustively over the past two decades that it's easy to remember things we only saw on television, or heard about later. I know these things, when I focus in a little harder on what I know to be true about my life back then, but the memories feel authentic. My husband was running late to his job in the West Village so by the time he got out of the subway, both towers were already on fire. But I thought nothing of it until a coworker emailed that a plane had crashed into the World Trade Center. I did hear, from our little apartment on the other side of the river in Brooklyn, something odd that Tuesday morning. In that version of events, my husband was stepping out of the subway when he saw the plane hit the second tower, and I called him on his cellphone. In my first recollection, the boom and the rumble when the plane hit the first tower were ominous.