Do you think the state of the art in quantum computing is already more advanced than we realize, in the same way that the state of the art in cryptography was when R, S, and A thought they had discovered RSA?
More seriously: people have mooted this possibility for as long as I've been in this field (~20 years). But keep in mind that, when Cocks and Williamson at GCHQ discovered what would later become known as RSA and Diffie-Hellman key exchange---so, 3-4 years ahead of the open world---cryptography essentially didn't yet exist as an academic subject. Almost all the action was still closely tied to the intelligence community. So, no surprise that a not-yet-existing discipline had fallen behind!
By contrast, quantum computing has been openly studied for decades and has thousands of people working on it all over the world. The central thing that causes me to be skeptical of the "million-qubit quantum computer sitting in the NSA's basement" hypothesis, is that we pretty much know who the best people are, and we haven't noticed any effort to vacuum them all up analogous to the Manhattan Project.
Like, it's no secret that the NSA and DoD, and other military and intelligence agencies around the world, are interested in this field and fund a good deal of work on it. In fact my main grant right now (the Vannevar Bush Faculty Fellowship) comes from the Office of Naval Research. But if the secret world is light-years ahead of the open world, then they'd also need to be executing a giant cover operation of pretending to care about what we in academia are doing! :) So at what point does it become an unfalsifiable conspiracy theory?
More seriously: people have mooted this possibility for as long as I've been in this field (~20 years). But keep in mind that, when Cocks and Williamson at GCHQ discovered what would later become known as RSA and Diffie-Hellman key exchange---so, 3-4 years ahead of the open world---cryptography essentially didn't yet exist as an academic subject. Almost all the action was still closely tied to the intelligence community. So, no surprise that a not-yet-existing discipline had fallen behind!
By contrast, quantum computing has been openly studied for decades and has thousands of people working on it all over the world. The central thing that causes me to be skeptical of the "million-qubit quantum computer sitting in the NSA's basement" hypothesis, is that we pretty much know who the best people are, and we haven't noticed any effort to vacuum them all up analogous to the Manhattan Project.
Like, it's no secret that the NSA and DoD, and other military and intelligence agencies around the world, are interested in this field and fund a good deal of work on it. In fact my main grant right now (the Vannevar Bush Faculty Fellowship) comes from the Office of Naval Research. But if the secret world is light-years ahead of the open world, then they'd also need to be executing a giant cover operation of pretending to care about what we in academia are doing! :) So at what point does it become an unfalsifiable conspiracy theory?