Bitcoin will exist as long as there's one or at least few computers running a bitcoin full node. What could possibly stop this? Probably a global blackout or a huge EMP(electromagnetic pulse)[1] or something.
Even if an EMP hit or a global blackout occurred, wouldn't that only be a temporary halt in activity? I don't think this would be the death of Bitcoin, unless I misunderstand something the blocks should just pick back up with extremely low-difficulty once we get power back.
I'm really not 100% sure, but yea I do think it will only be a temporary halt. What I think is though, that EMP can actually destroy electronic hardware, not just sort of crash/stop them like when a blackout occurs. Though it's probably unlikely for an EMP to destroy 100% of the harddrives of the whole world.
EMP interference is generally disruptive or damaging to electronic equipment, and at higher energy levels a powerful EMP event such as a lightning strike can damage physical objects such as buildings and aircraft structures. -Wikipedia
You raise some interesting points. The most likely cause of a worldwide failure of technology is a Coronal Mass Ejection (CME) - a release of plasma and magnetic field from the sun. There was a major CME that hit Earth in 1859, that if it happened today, would likely disable/damage/destory all electrical equipment on Earth. There was another big one in 2012 that passed through our orbit, but just missed Earth. If it had hit us, the estimated time to global recovery would be 4-10 years.
Be interesting to see how crypto would cope with this. Theoretically, it is possible that all copies of the blockchain were destroyed, or that only one or two people were still able to run nodes. A lot of wallets would be destroyed and lost forever. Would crypto even be viable if it would take 10 years for global recovery? I feel people might have more important things to deal with.