Quantum Random Number Generation Breakthrough in India

Indian scientists achieved a landmark in digital security by developing a method to generate and certify truly random numbers using quantum computing. The research, led by Urbasi Sinha at the Raman Research Institute, Bengaluru, utilised a general-purpose quantum computer to demonstrate this technique. This advancement is poised to revolutionise cybersecurity by enabling hack-proof encryption systems.

Importance of Random Numbers in Digital Security

Random numbers form the backbone of encryption and authentication systems. True randomness means numbers are generated without any predictable pattern. Currently, most systems use pseudorandom numbers created by algorithms. These appear random but can theoretically be predicted if the algorithm or its input is known. Quantum computers threaten this security by potentially cracking such pseudorandom sequences faster than classical computers.

Quantum Randomness and Its Natural Basis

True randomness exists in nature, especially in quantum phenomena. Particles like photons exist in multiple states simultaneously and only settle into one state when measured. This collapse is fundamentally unpredictable. Quantum Random Number Generators (QRNGs) exploit this property to produce sequences of random bits. However, device faults or biases can compromise the randomness and security, raising the need for certification.

Certification Challenges in Quantum Random Number Generation

Certification ensures that the randomness is genuine and not due to device errors or tampering. It requires proving that the outcomes stem from intrinsic quantum unpredictability. Traditionally, this has been done by testing entangled particles separated by large distances to rule out interference. Such setups are impractical outside laboratories, limiting real-world applications.

Innovative Approach Using Leggett-Garg Inequality

Urbasi Sinha’s team bypassed the need for spatial separation by using time separation in a single particle. They tested violations of the Leggett-Garg inequality, a quantum property indicating non-classical behaviour over time. In 2024, they generated certified true random numbers in a loophole-free experiment. Recently, this was successfully replicated on a commercial quantum computer, proving robustness against noise and environmental disturbances.

Implications and Future Prospects

This breakthrough marks step towards practical quantum random number generators for real-life digital security. It aligns with India’s National Quantum Mission goals. While currently at the laboratory scale, further development and funding could lead to commercial products. These would enhance cybersecurity by making encryption theoretically unbreakable even by quantum computers.

Questions for UPSC:

1. Point out the significance of quantum computing in transforming cybersecurity and digital encryption methods.
2. Critically analyse the challenges in certifying true randomness in quantum random number generation with suitable examples.
3. Estimate the impact of India’s National Quantum Mission on scientific research and technological innovation in the country.
4. What is the Leggett-Garg inequality? How does its violation help in establishing quantum behaviour in particles?

Answer Hints:

1. Point out the significance of quantum computing in transforming cybersecurity and digital encryption methods.

1. Quantum computers exploit quantum superposition and entanglement, enabling processing beyond classical limits.
2. They can potentially break classical encryption relying on pseudorandom numbers and factorization (e.g., RSA) faster via algorithms like Shor’s.
3. Quantum-generated true random numbers enhance encryption security by providing unpredictability unattainable by classical means.
4. Quantum cryptography protocols (e.g., Quantum Key Distribution) offer theoretically unbreakable security based on quantum laws.
5. Integration of quantum techniques can future-proof digital security against emerging quantum hacking threats.
6. Quantum computing drives innovation in secure communication, authentication, and data protection frameworks worldwide.

2. Critically analyse the challenges in certifying true randomness in quantum random number generation with suitable examples.

1. True randomness must be proven to arise from intrinsic quantum unpredictability, not device faults or external manipulation.
2. Device bias or hardware imperfections can introduce patterns, compromising randomness quality and security.
3. Certification traditionally requires loophole-free Bell test experiments with spatially separated entangled particles, which are large and impractical setups.
4. Example – Bell’s Inequality violation confirms entanglement-based randomness but demands particle separation over hundreds of meters.
5. Noise and environmental disturbances in real-world devices challenge reliable certification outside controlled labs.
6. New approaches like time-separated measurements (Leggett-Garg inequality) help overcome spatial separation issues but require rigorous validation.

3. Estimate the impact of India’s National Quantum Mission on scientific research and technological innovation in the country.

1. Provides focused funding and infrastructure to advance quantum technologies and fundamental research in India.
2. Supports breakthroughs like Urbasi Sinha’s certified quantum random number generation, enhancing global scientific stature.
3. Encourages collaboration between academia, industry, and government for applied quantum solutions.
4. Accelerates development of quantum computing, communication, and sensing technologies with strategic and commercial potential.
5. Promotes skill development and talent retention in cutting-edge quantum science and engineering fields.
6. Positions India competitively in the global quantum technology race, encouraging innovation-led economic growth.

4. What is the Leggett-Garg inequality? How does its violation help in establishing quantum behaviour in particles?

1. The Leggett-Garg inequality tests whether a system’s properties over time can be explained by classical realism and non-invasive measurability.
2. It distinguishes between classical (macrorealistic) and quantum temporal correlations in a single system’s evolution.
3. Violation of this inequality implies that the system cannot be described by classical physics and exhibits quantum coherence over time.
4. This confirms non-classical behaviour without requiring spatially separated particles, easing experimental constraints.
5. Used to certify genuine quantum randomness by demonstrating that measurement outcomes are fundamentally unpredictable.
6. Urbasi Sinha’s team used this violation on a commercial quantum computer to generate certified true random numbers robustly.