Quantum Computing: Basic Principles and India’s National Mission
GS Paper 3 – Science & Technology
Quantum Computing represents a paradigm shift in computation, leveraging principles of quantum mechanics to solve problems that are practically impossible for classical computers. With countries across the world investing heavily in this frontier technology, India has also launched a National Mission on Quantum Technologies and Applications (NM-QTA) to build indigenous capabilities.
For UPSC aspirants, quantum computing is important due to its relevance in emerging technologies, national security, economic competitiveness, and technological self-reliance.
What is Quantum Computing?
Quantum Computing is a type of computation that uses the principles of quantum mechanics—such as superposition and entanglement—to process information.
Unlike classical computers that use bits (0 or 1), quantum computers use quantum bits or qubits, which can exist in multiple states simultaneously.
Key Concepts in Quantum Computing
1. Qubit
A qubit is the basic unit of quantum information.
It can exist as:
- 0
- 1
- Both 0 and 1 at the same time (superposition)
2. Superposition
Superposition allows a qubit to exist in multiple states simultaneously, enabling quantum computers to process many possibilities at once.
3. Entanglement
Entanglement is a phenomenon where two or more qubits become linked such that the state of one instantly affects the other, even over large distances.
4. Quantum Interference
Quantum interference is used to amplify correct solutions and cancel out incorrect ones during computation.

How Quantum Computers Differ from Classical Computers
| Classical Computing | Quantum Computing |
|---|---|
| Uses bits (0 or 1) | Uses qubits |
| Sequential processing | Parallel processing |
| Limited scalability | Exponential computing power |
| Energy-intensive for complex problems | Efficient for complex simulations |
Applications of Quantum Computing
1. Cryptography and Cybersecurity
Quantum computers can:
- Break traditional encryption algorithms
- Enable quantum cryptography and secure communication
This has major implications for national security and defence.
2. Drug Discovery and Healthcare
Quantum computing can:
- Simulate molecular interactions
- Accelerate drug development
- Improve precision medicine
3. Climate Modelling and Weather Forecasting
Quantum systems can:
- Improve climate simulations
- Enhance disaster prediction accuracy
4. Artificial Intelligence and Machine Learning
Quantum algorithms can:
- Speed up pattern recognition
- Optimize large datasets
- Improve AI training efficiency
5. Optimization Problems
Used in:
- Logistics and supply chain management
- Traffic systems
- Financial portfolio optimization

Challenges in Quantum Computing
- High error rates (quantum decoherence)
- Need for extremely low temperatures
- High cost of infrastructure
- Lack of skilled manpower
These challenges make government support and long-term investment essential.
India’s National Mission on Quantum Technologies and Applications (NM-QTA)
Launch and Objective
India launched the National Mission on Quantum Technologies and Applications to develop:
- Quantum computing
- Quantum communication
- Quantum sensing
- Quantum materials
The mission aims to position India among the global leaders in quantum technology.
Key Focus Areas of NM-QTA
- Development of quantum computers with indigenous hardware
- Secure quantum communication networks
- Quantum-enabled sensors for strategic sectors
- Capacity building and skill development
- Collaboration between academia, industry, and government
Strategic Importance for India
Quantum technology supports:
- Atmanirbhar Bharat
- Strategic autonomy
- Advanced defence capabilities
- Future-ready digital economy
It also reduces dependence on foreign technology in critical areas.

Global Context and India’s Position
Countries like:
- United States
- China
- European Union
have already made significant investments in quantum research.
India’s mission ensures that the country remains competitive in emerging technologies.
Relevance for UPSC Prelims and Mains
Prelims
- Definitions of qubit, superposition, and entanglement
- Matching applications with sectors
- Government initiatives in quantum technology
Mains (GS 3)
- Role of emerging technologies in economic development
- National Mission on Quantum Technologies
- Challenges and policy support needed
Way Forward
- Strengthening research institutions
- Public–private partnerships
- International collaboration
- Skill development in quantum science
- Ethical and security frameworks
Conclusion
Quantum computing is no longer a theoretical concept—it is a strategic technology of the future. India’s National Mission on Quantum Technologies reflects a proactive approach towards technological self-reliance, innovation, and national security.
For UPSC aspirants, understanding the basic principles, applications, and policy initiatives related to quantum computing is essential for both Prelims and Mains.
FAQs – Quantum Computing
What is a qubit?
A qubit is the basic unit of quantum information that can exist in multiple states simultaneously.
Why is quantum computing important for national security?
It affects encryption, secure communication, and defence technologies.
What is India’s National Mission on Quantum Technologies?
A government initiative to develop indigenous quantum computing and related technologies.
Is quantum computing used commercially today?
It is mostly in experimental and early-stage applications.
Which UPSC paper covers quantum computing?
GS Paper 3 – Science and Technology.



