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>A bit has the storage capacity of 2 distinct bits of information. A qubit has the storage capacity of 2 complex numbers, which corresponds to 4 floats, which is at least 16*8 bits of information if we are conservative about our assumptions.

This whole explanation makes qubits sound just like a combo-pack of bits, or like something you'd find in an analog computer. They're much more powerful than that because they can be put into superpositions and entangled together while you continue to do calculations with them. Using superpositions and entanglement across qubits can let you solve some problems with lower-complexity algorithms than you could with classical computers.

It's like saying a car is defined by four tires being in close proximity, while skipping the fact that the usefulness of a car comes from the tires being connected together and steered which lets you do things that no amount of unconnected tires could do.



And also, qubits can't be used as compressed data storage. Despite the fact that it takes two real numbers to specify the state of a qubit, you only get one bit out when you measure it, with the rest of the information being destroyed.


The whole point of Quantum Supremacy test is to show that qubits can in fact store distributions in their state which is another way of saying some carefully crafted equations are storable inside qubits as long as you are interested in an approximate and numeric output. One can argue a MIDI audio or a SVG graphic is exactly that, a carefully crafted equation which even in its lossy form (mp3, jpg) is able to convey meaning.




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