Change detection in high-dimensional data streams using quantum devices

One or more non-transitory computer-readable storage media configured to store instructions that, in response to being executed, cause a system to perform operations, the operations comprising:

• obtaining a first quantum state representing a first data subset of a multivariate dataset that describes a plurality of data samples in terms of a plurality of variables;
• obtaining a second quantum state representing a second data subset of the multivariate dataset;
• configuring a quantum circuit that includes:
• an ancillary qubit initialized to a zero state,
• a first qubit including the first quantum state, and
• a second qubit including the second quantum state;
• applying a first Hadamard transformation to the ancillary qubit in which the first Hadamard transformation returning a particular value results in swapping the first qubit and the second qubit;
• responsive to the first Hadamard transformation returning the particular value, swapping the first qubit and the second qubit such that the second qubit represents the first quantum state and the first qubit represents the second quantum state;
• applying a second Hadamard transformation to the ancillary qubit and observing a measurement outcome of the second Hadamard transformation;
• and
• responsive to the measurement outcome being observed as having a value of zero, determining that a changepoint does not occur between the data samples corresponding to the first data subset and the data samples corresponding to the second data subset.

A system, comprising:

• one or more processors;
• and
• one or more non-transitory computer-readable storage media configured to store instructions that, in response to being executed, cause the system to perform operations, the operations comprising:
• obtaining a first quantum state representing a first data subset of a multivariate dataset that describes a plurality of data samples in terms of a plurality of variables;
• obtaining a second quantum state representing a second data subset of the multivariate dataset;
• configuring a quantum circuit that includes:
• an ancillary qubit initialized to a zero state,
• a first qubit including the first quantum state, and
• a second qubit including the second quantum state;
• applying a first Hadamard transformation to the ancillary qubit in which the first Hadamard transformation returning a particular value results in swapping the first qubit and the second qubit;
• responsive to the first Hadamard transformation returning the particular value, swapping the first qubit and the second qubit such that the second qubit represents the first quantum state and the first qubit represents the second quantum state;
• applying a second Hadamard transformation to the ancillary qubit and observing a measurement outcome of the second Hadamard transformation;
• and
• responsive to the measurement outcome being observed as having a value of zero, determining that a changepoint does not occur between the data samples corresponding to the first data subset and the data samples corresponding to the second data subset.