QUBITS: WAY BETTER THAN ZEROES AND ONES
A computer made up of quantum bits (qubits, for short) is really a collection of
circuits. As in a classical computer made up of bits, the input values proceed
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computing and classical computing is that bits are binary. They are either up or
down, open or closed, zero or one. Qubits, on the other hand, can be
entangled—present in multiple states at once, a so-called superposition.
If you’re trying to solve a complex algorithm, say, as part of a software
application to run on a classical computer, you’ll need to string together
multiple bits of zeros and ones. But if you’re running an algorithm using qubits,
you might need only a single qubit in a superposition to replace all those
classical bits. String multiple qubits together into a quantum circuit, and the
possibilities are staggering. Theoretically, you could run an algorithm so
complex that there’s no analog to classical computing as we know it.
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communications is the fragility of the quantum state of matter. We are starting
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and road vibrations, but only in test loops—not over the thousands of miles
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how to make qubits function reliably, even in a controlled laboratory setting.
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computations, as IBM demonstrated using a stable 27-qubit computer called
Falcon earlier this year. They’re mostly useful for testing purposes: Researchers
can feed them problems with known solutions and then validate their answers.
Photo^ credit:^ JIBM
IBM Quantum
27-Qubit Falcon
Chip with Quantum
Volume 64