lol. that famous quote from einstein springs to mind. but there is other very likely threats that will put us right back to the stone age. iron age if we are prepared a little. steam age if we prepared a lot. and most people washed away and/or covered in mud. or possibly also, lit on fire by the sun, or maybe exploded by a mega lightning strike. speaking of which, in south carolina yesterday:
https://www.facebook.com/mountpleasantpd/videos/lightning-strike/732773119645376