Quantum Computing exam
1. Divine Zoe Criteria for Quantum Computer Construction: Outline the
Essential Requirements.
Answer: The "divine Zoe criteria" is not a standard, recognized term in quantum
computing. However, the essential requirements for constructing a functional
quantum computer, often attributed to David DiVincenzo, include:
Well-defined and scalable qubits: The system must possess physical
entities that can reliably represent qubits, and it should be feasible to
increase the number of these qubits.
Ability to initialize qubits to a simple fiducial state: It must be possible to
reliably set all qubits to a known initial state, such as ∣00...0⟩.
Long relevant decoherence times: The quantum states of the qubits must
be maintained for a duration significantly longer than the time required to
perform quantum operations.
Universal set of quantum gates: The system must be capable of
implementing a set of quantum gates that can approximate any arbitrary
unitary transformation.
Qubit-specific measurement capability: It must be possible to measure the
state of individual qubits with high fidelity.
Ability to interconvert stationary and flying qubits (for quantum
communication): While not strictly required for computation itself, this is
crucial for building quantum networks.
Strong interaction between qubits: The ability to entangle and manipulate
the states of multiple qubits is essential for complex quantum algorithms.
2. Computational Time Equivalence: According to IBM, How Long Would a
Supercomputer Take to Match the Sycamore Processor's Computation?
Answer: IBM claimed that a classical supercomputer would take approximately
2.5 days to perform the same computation demonstrated by Google's Sycamore
processor in their quantum supremacy experiment.
3. Shor's Algorithm: What Specific Quantum Operation Does Its Quantum
Component Perform?
,Answer: The quantum part of Shor's algorithm is specifically designed to find the
period of a function that is modulo an integer N. This period-finding capability
is the core quantum advantage that allows for efficient factorization.
4. Function Output Classification: Provide an Example of an Output Neither
"Constant" Nor "Balanced".
Answer: An example of the output of a function that is neither "constant" nor
"balanced" for a 4-bit input is 0001.
A "constant" function would output the same value for all inputs (e.g., 0000
or 1111).
A "balanced" function for n bits would output an equal number (2n−1) of 0s
and 1s. For a 4-bit output, this would mean eight 0s and eight 1s across all
possible inputs.
The output "0001" contains three zeros and one one, thus not fitting either the
"constant" or "balanced" criteria across all possible inputs.
5. Quantum Supremacy Claim: What Was Google's Estimated Time for a
Supercomputer to Replicate the Sycamore Processor's Task?
Answer: Google estimated that a classical supercomputer would take
approximately 10,000 years to perform the same computation achieved by their
Sycamore processor in their quantum supremacy experiment.
6. Grover's Algorithm: What Does the Input Size N Refer To?
Answer: In Grover's algorithm, the input size N refers to the size of a database
being searched. The algorithm can find a specific item in an unsorted database of N
items quadratically faster than classical search algorithms.
7. Encryption Scheme Purpose: What is the Fundamental Goal of an
Encryption Scheme?
Answer: The fundamental purpose of an encryption scheme is to allow two
parties to send encrypted messages securely even when a third party (an
eavesdropper) is listening. Encryption transforms the original message into an
unreadable format, ensuring confidentiality.
, 8. Current Quantum Computer Limitations: Why Can't Today's Quantum
Computers Break Practical Encryption Schemes?
Answer: Currently available quantum computers are not capable of breaking
encryption schemes used for practical problems due to several key limitations:
Insufficient number of qubits: Current quantum computers do not have a
sufficiently large number of stable and interconnected qubits required to run
complex algorithms like Shor's algorithm on the scale needed to break
modern encryption.
Lack of robust error correction: Quantum computations are highly
susceptible to errors (decoherence, gate errors). Effective quantum error
correction techniques are still under development and not yet implemented
at a scale necessary for fault-tolerant quantum computation.
Short decoherence times: The quantum states of qubits are fragile and tend
to lose their quantum properties (decohere) relatively quickly, limiting the
complexity and duration of computations.
9. Google's Quantum Supremacy Experiment: What Was the Role of the
Supercomputer?
Answer: The supercomputer in Google's quantum supremacy experiment was used
to simulate and verify the behavior of the quantum computing process. Its role
was to attempt to perform the same complex computation as the Sycamore
processor, allowing researchers to estimate the time a classical computer would
take and thus demonstrate the quantum advantage.
10. Quantum Simulation Algorithm Goals: What is One Primary Objective?
Answer: One primary objective of a quantum simulation algorithm is to find the
ground state energy of a given quantum system. This is crucial in fields like
materials science and quantum chemistry for understanding the fundamental
properties of molecules and materials.
11. Trapped Ion Quantum Computers: Where is Information Stored?
Answer: In trapped ion quantum computers, information is stored in the
electronic states of ions. Specific energy levels within the ions are used to
represent the ∣0⟩ and ∣1⟩ states of the qubits.
12. Bit Flip Code: Which Quantum Gates Does it Utilize?
1. Divine Zoe Criteria for Quantum Computer Construction: Outline the
Essential Requirements.
Answer: The "divine Zoe criteria" is not a standard, recognized term in quantum
computing. However, the essential requirements for constructing a functional
quantum computer, often attributed to David DiVincenzo, include:
Well-defined and scalable qubits: The system must possess physical
entities that can reliably represent qubits, and it should be feasible to
increase the number of these qubits.
Ability to initialize qubits to a simple fiducial state: It must be possible to
reliably set all qubits to a known initial state, such as ∣00...0⟩.
Long relevant decoherence times: The quantum states of the qubits must
be maintained for a duration significantly longer than the time required to
perform quantum operations.
Universal set of quantum gates: The system must be capable of
implementing a set of quantum gates that can approximate any arbitrary
unitary transformation.
Qubit-specific measurement capability: It must be possible to measure the
state of individual qubits with high fidelity.
Ability to interconvert stationary and flying qubits (for quantum
communication): While not strictly required for computation itself, this is
crucial for building quantum networks.
Strong interaction between qubits: The ability to entangle and manipulate
the states of multiple qubits is essential for complex quantum algorithms.
2. Computational Time Equivalence: According to IBM, How Long Would a
Supercomputer Take to Match the Sycamore Processor's Computation?
Answer: IBM claimed that a classical supercomputer would take approximately
2.5 days to perform the same computation demonstrated by Google's Sycamore
processor in their quantum supremacy experiment.
3. Shor's Algorithm: What Specific Quantum Operation Does Its Quantum
Component Perform?
,Answer: The quantum part of Shor's algorithm is specifically designed to find the
period of a function that is modulo an integer N. This period-finding capability
is the core quantum advantage that allows for efficient factorization.
4. Function Output Classification: Provide an Example of an Output Neither
"Constant" Nor "Balanced".
Answer: An example of the output of a function that is neither "constant" nor
"balanced" for a 4-bit input is 0001.
A "constant" function would output the same value for all inputs (e.g., 0000
or 1111).
A "balanced" function for n bits would output an equal number (2n−1) of 0s
and 1s. For a 4-bit output, this would mean eight 0s and eight 1s across all
possible inputs.
The output "0001" contains three zeros and one one, thus not fitting either the
"constant" or "balanced" criteria across all possible inputs.
5. Quantum Supremacy Claim: What Was Google's Estimated Time for a
Supercomputer to Replicate the Sycamore Processor's Task?
Answer: Google estimated that a classical supercomputer would take
approximately 10,000 years to perform the same computation achieved by their
Sycamore processor in their quantum supremacy experiment.
6. Grover's Algorithm: What Does the Input Size N Refer To?
Answer: In Grover's algorithm, the input size N refers to the size of a database
being searched. The algorithm can find a specific item in an unsorted database of N
items quadratically faster than classical search algorithms.
7. Encryption Scheme Purpose: What is the Fundamental Goal of an
Encryption Scheme?
Answer: The fundamental purpose of an encryption scheme is to allow two
parties to send encrypted messages securely even when a third party (an
eavesdropper) is listening. Encryption transforms the original message into an
unreadable format, ensuring confidentiality.
, 8. Current Quantum Computer Limitations: Why Can't Today's Quantum
Computers Break Practical Encryption Schemes?
Answer: Currently available quantum computers are not capable of breaking
encryption schemes used for practical problems due to several key limitations:
Insufficient number of qubits: Current quantum computers do not have a
sufficiently large number of stable and interconnected qubits required to run
complex algorithms like Shor's algorithm on the scale needed to break
modern encryption.
Lack of robust error correction: Quantum computations are highly
susceptible to errors (decoherence, gate errors). Effective quantum error
correction techniques are still under development and not yet implemented
at a scale necessary for fault-tolerant quantum computation.
Short decoherence times: The quantum states of qubits are fragile and tend
to lose their quantum properties (decohere) relatively quickly, limiting the
complexity and duration of computations.
9. Google's Quantum Supremacy Experiment: What Was the Role of the
Supercomputer?
Answer: The supercomputer in Google's quantum supremacy experiment was used
to simulate and verify the behavior of the quantum computing process. Its role
was to attempt to perform the same complex computation as the Sycamore
processor, allowing researchers to estimate the time a classical computer would
take and thus demonstrate the quantum advantage.
10. Quantum Simulation Algorithm Goals: What is One Primary Objective?
Answer: One primary objective of a quantum simulation algorithm is to find the
ground state energy of a given quantum system. This is crucial in fields like
materials science and quantum chemistry for understanding the fundamental
properties of molecules and materials.
11. Trapped Ion Quantum Computers: Where is Information Stored?
Answer: In trapped ion quantum computers, information is stored in the
electronic states of ions. Specific energy levels within the ions are used to
represent the ∣0⟩ and ∣1⟩ states of the qubits.
12. Bit Flip Code: Which Quantum Gates Does it Utilize?
