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Computer Science
Quantum Computing
Quantum Computing
1. Foundations of Quantum Computing
2. The Qubit: The Quantum Bit
3. Multi-Qubit Systems
4. Quantum Gates and Circuits
5. Core Quantum Phenomena for Computation
6. Quantum Algorithms
7. Physical Realizations of Quantum Computers
8. Challenges in Building Quantum Computers
9. Applications and Impact
10. Quantum Software and Programming
11. Advanced Topics and Future Directions
The Qubit: The Quantum Bit
Definition of a Qubit
Mathematical Definition
Physical Realizations of Qubits
Comparison to Classical Bits
Representing Qubit States
Basis States |0⟩ and |1⟩
Computational Basis
Physical Interpretation
Standard Basis Vectors
General Qubit State
Complex Coefficients
Normalization Condition
Global Phase
The Bloch Sphere Representation
Geometric Representation
Polar and Azimuthal Angles
Visualization of Pure States
Antipodal Points
Superposition
Linear Combinations of Basis States
Superposition Principle
Equal Superposition States
Probability Amplitudes
Squared Modulus and Measurement Probability
Phase Information
Measurement in the Computational Basis
The Measurement Postulate
Projective Measurement
Measurement Operators
Collapse of the Wave Function
Post-Measurement State
Irreversibility of Measurement
Probabilistic Nature of Measurement
Born Rule
Repeated Measurements
Statistical Interpretation
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1. Foundations of Quantum Computing
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3. Multi-Qubit Systems