What exactly is the Nothing-At-Stake problem in Proof-of-Stake consensus networks?

While I understand what the nothing at stake problem means, I do not really understand the security implications....

The investigation into the Thailand bitcoin fraud case involving a Finnish national who lost 5,564 bitcoins to Thai fraudsters has now widened its reach to include a stock investor and bank employees.

A total of nine cryptocurrency operators have either received or are in the process of receiving regulatory approval in Thailand.

FCoin (<a href="https://www.fcoin.com/" target="_blank">https://www.fcoin.com</a>) is a crypto exchange that began trading in May 2018. It is maybe best known in the US and Europe for <a href="https://www.ccn.com/chinese-exchange-fcoin-accused-of-crippling…

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