Quantum computing is fascinating and powerful, leveraging quantum mechanical principles e.g. superposition, entanglement & interference to solve problems no classical computer could. But there's something a classical computer can do that a quantum processor can't: CTRL-C CTRL-V

The no-cloning theorem says you cannot copy an arbitrary unknown quantum state without disturbing it. This breaks a bevy of classical tricks we rely on all the time at all levels of classical computing: - Copy state → operate on the copy - Fan-out signals - Cache intermediate results - Retry by duplication

In short, our existing concept of RAM doesn't work in the quantum computing paradigm. You can't just "read" a memory address without potentially collapsing the superposition of the address register or the data itself.

In other words, "state" in the classical sense is an infinite resource, as it can simply be copied and used anywhere. Quantum states, on the other hand (including entangled states that power Shor's algorithm), are effectively *created* and then *consumed*

In fact, this reality creates one of the biggest barriers to a CRQC. In algorithms like Shor's the biggest overhead is cultivating a specific set of entangled states & teleporting them into the circuit, all in a fault-tolerant way.

In light of this fact, the current state of progress in quantum that's been made over the last year has been extraordinary. Quantum computing represents the frontier in many disciplines: information theory, computer science, physics, and engineering. Realizing a fault tolerant quantum computer, thus, will represent one of the most important technological breakthroughs for humanity