There exists quantum key distribution https://en.wikipedia.org/wiki/Quantum_key_distribution#Quantum_key_distribution_networks https://en.wikipedia.org/wiki/Qua

There exists quantum key distribution https://en.wikipedia.org/wiki/Quantum_key_distribution#Quantum_key_distribution_networks https://en.wikipedia.org/wiki/Quantum_key_distribution#Quant... which is provably secure (up to side channel attacks), and allows two parties (say you and your bank) to remotely create a symmetric key. This will certainly require infrastructure to be built, but its possible that this infrastructure consists of beaming signals from bank->satellite->receiver in your home.