What would happen to Bitcoin if the internet or power would be shut down for a moment, all over the world? Would this destroy Bitcoin or other block chain based money or technology?
What would happen to Bitcoin if the internet or power would be shut down for a moment
It depends how long that moment is.
Generally there would be no long-term harmful effect on Bitcoin for any outage of a few minutes or even several hours.
Longer outages of many days or weeks would skew the next recalculation of mining difficulty and result in blocks being produced significantly faster than one every ten minutes for about two weeks.
The difficulty is adjusted every 2016 blocks based on the time it took to find the previous 2016 blocks. At the desired rate of one block each 10 minutes, 2016 blocks would take exactly two weeks to find. If the previous 2016 blocks took more than two weeks to find, the difficulty is reduced. If they took less than two weeks, the difficulty is increased. The change in difficulty is in proportion to the amount of time over or under two weeks the previous 2016 blocks took to find.
For really long outages there might be other effects and different software might react in different ways.
The above is speculation. I'd either look for a prior study of the subject or inspect some source code (such as that for Bitcoin core) to see how it might handle these time-related aspects of Bitcoin.
A timestamp is accepted as valid if it is greater than the median timestamp of previous 11 blocks, and less than the network-adjusted time + 2 hours.
So a long gap in the blockchain timestamps shouldn't be an issue for block validation.