Is there a race to develop Quantum Computers? The answer is Yes, because quantum technology will have far-reaching impact ranging from cybersecurity to drug discovery, development of new materials, financial modelling and supply chain optimizations. It will also boost the development of next generation of artificial intelligence leading to enhanced medical imaging, natural resource exploration and global navigation without GPS satellites.
Since the subject is vast, let me address the most crucial aspect of cybersecurity. Today, a fusion of technologies is blurring the lines between the physical, digital, and biological spheres. Every time we use an e-commerce site on our web browser or send and receive emails or check our bank or credit card accounts, the online services use Hypertext Transfer Protocol Secure (HTTPS), a web protocol that uses cryptography to convert original data or message into an unreadable format to provide protection to all our communications as well as things like passwords, digital signatures and health records. It plays a crucial role in ensuring the confidentiality, integrity, and authenticity of data. Cryptography involves two steps, i) Encryption and ii) Decryption. Encryption is a process, through which a plain text is converted into an encoded text called as cipher text and Decryption is vice-a-versa by using respective algorithms. Two types of keys are inbuilt in these algorithms namely, private key and public key. In private key cryptography, both the sender and receiver share the same private key, which is known only to both of them. While in public key cryptography, both the sender and receiver have their own private key and all they exchange over the channel is a public key.
At present RSA algorithm developed by Ron Rivest, Adi Shamir and Leonard Adleman is used in cryptography to encrypt or decrypt data. It is an asymmetric cryptography algorithm that works on two different keys, namely public and private key. Let me explain how cryptography works. Two enormous prime numbers are selected and multiplied and the product gets published and is a part of the encryption key needed to generate the decryption key. It looks very simple to break the encryption as the product of two numbers is already provided and only factors need to be worked out to decrypt the message. But, it is not so. Let me demonstrate in three examples, i) let us take a number N=15 and output its factors that is 3×5=15, easy, ii) let us take a larger number N=694921 and output its factors that is 787×883=694921, iii) and if N=188,538,889,076,768,372,354,881,165,818,173,073,829 what
would be output factors? Extremely difficult. In the third case N is a combination of two 64- bit primes, with 20 digits each. A 64-bit number ranges from 0 to 18,446,744,073,709,551,616 and have a vast number of prime numbers in between!
The idea behind RSA algorithm is that it is difficult to factorize a large integer. It uses a public key and a private key. The public key can be shared with everyone, while the private key must be kept secret. The keys are based on a very large number that is the product of two large prime numbers. Finding the prime factors of this large number is very difficult, and that’s what makes the algorithm secure. The encryption strength lies on the key size and if it is doubled or tripled, the strength of encryption increases exponentially. RSA keys at present are typically 1024 or 2048 bits long, but experts believe that 1024-bit keys could be broken in the near future with the development of quantum computers. However, at present it seems to be an infeasible task.
The question is, ‘will the quantum computers break into the cryptographic defences?’ Quantum computing is a revolutionary paradigm that harnesses the principles of quantum
mechanics to perform computations in ways that classical computers cannot. A quantum (plural: quanta) is the smallest discrete unit of a phenomenon. For example, a quantum of light is a photon, and a quantum of electricity is an electron. Today’s computers use bits, a stream of electrical or optical pulses representing 0 or 1 digits. Everything from our tweets and e-mails to iTunes songs or the YouTube videos are essentially long strings of these binary digits. On the contrary, quantum bits, or qubits, can exist in a superposition of states, meaning they can be 0, 1, or any combination of 0 and 1, simultaneously. This property enables quantum computers to explore multiple possibilities in parallel. Another property in quantum mechanics is entanglement where the states of two or more qubits become correlated in such a way that the state of one qubit is dependent on the state of the others. This correlation persists even when the qubits are separated by large distances. Entanglement allows for the creation of complex relationships between qubits, enhancing the computational power of quantum systems. Already, Shor’s algorithm named after Peter Shor, a mathematician is developed to run on a quantum computer for integer factorization.
But, development of quantum hardware is still a distant goal. Developing high quality qubits that are fundamental building blocks of a quantum computer is extremely challenging. Noise and decoherence can cause qubits to lose their quantum properties. Scaling up the number of qubits that are required to outperform classical computers for complex problems while maintaining low error rates is yet another challenge. Lastly, quantum hardware requires extremely low temperatures, isolation from external influences, and precise control systems for maintenance. At present IBM and Google are leading the race along with research in universities in USA, UK, Australia, China, Singapore, Austria, Canada and Germany. Thanks to the Modi government initiative, India, too have launched its National Quantum Mission with a budget outlay of Rupees 2,819 crore. A couple of years back, IISc, Bangalore, IIT, Roorkee and Centre C-DAC jointly developed country’s first ‘Quantum Computer Simulator (QSim) Toolkit’.
Sooner than later, quantum technology bomb could become cyber threats putting personal information to governments’ military and intelligence data at risk. There is an urgent need to develop quantum-safe encryption and secure quantum communication protocols that is crucial to ensure data security in the quantum era. The threat is real with the strategy of “Store Now, Decrypt Later attacks” in which encrypted data is being harvested today so that it can be decrypted when a quantum computer is available. The global quantum technology market is projected to reach $106 billion by 2040 and Modi government needs to floor the accelerator to be ahead in this race.
Former Sr. scientist, CSIR-NGRI
