When I was on The Wealthy Barber podcast , the last question David Chilton asked me that I think needs a fuller answer takes me back to my working career as a cryptographer:  “Will quantum computers crack bitcoin?”  The short answer is probably not, but it’s not impossible. Quantum computers work differently from regular computers that we’re familiar with. A fully-functioning quantum computer can try many combinations of inputs simultaneously, rather than trying them one at a time.  In some cases, secret keys used in cryptography are vulnerable; a quantum computer can try all possible secret keys simultaneously when breaking a system.  This could affect the digital signatures used in bitcoin, but not the coin mining. However, we don’t have fully-functioning quantum computers yet.  Engineers are having great difficulty making larger quantum computers work.  The main problem is called decoherence.  Regular computers have bits, and quantum computers have ...