Quantum vs Classical Computing

1. Introduction

Quantum computing is a revolutionary technology that harnesses the principles of quantum mechanics to perform computations that would be infeasible for classical computers. This lesson explores the core concepts of quantum and classical computing, focusing on their differences, advantages, and limitations.

2. Core Concepts

2.1 Classical Computing

Classical computing is based on the manipulation of bits, which can either be 0 or 1. These bits are processed using logical operations to perform computations. Key characteristics include:

• Deterministic operations
• Sequential processing
• Binary representation of data

2.2 Quantum Computing

Quantum computing utilizes quantum bits or qubits, which can exist in superpositions of states (both 0 and 1 simultaneously). This allows quantum computers to perform multiple computations at once. Key principles include:

• Superposition: A qubit can represent multiple states
• Entanglement: Qubits can be correlated with each other
• Quantum interference: Quantum states can combine to enhance or cancel probabilities

3. Comparison

The following table summarizes the key differences between classical and quantum computing:

4. Code Examples

Here’s a simple example using Qiskit, a popular quantum computing framework:

from qiskit import QuantumCircuit, Aer, execute

# Create a Quantum Circuit with 2 qubits
qc = QuantumCircuit(2)

# Apply a Hadamard gate to the first qubit
qc.h(0)

# Apply a CNOT gate
qc.cx(0, 1)

# Measure the qubits
qc.measure_all()

# Execute the circuit
simulator = Aer.get_backend('aer_simulator')
result = execute(qc, backend=simulator, shots=1000).result()
counts = result.get_counts(qc)
print(counts)
            

This code constructs a simple entangled state using two qubits and measures the outcome.

5. FAQ