Encryption

• Every online transaction we make with another person is protected so that a third person cannot read it without the permission of the two people exchanging the information in the first place. This process is called encryption of the data.
• The mathematical problem known as integer factorisation is one of the methods presently used to encrypt our secret or private messages. 
• There are other methods using the so-called discrete logarithm problem, which would take a normal computer exponentially large time to crack.

Quantum computers

• One of the basic elements that make up this quantum computer is that where the classical one uses bits to compute this one uses “qubits”.
• Classical bits can take the value 0 or 1, allowing for a binary system to be set up and the lowest level of computer language is done manipulating these bits. A qubit on the other hand can exist as a superposition of two states 0 and 1. So if you have an n-qubit number, it can exist as a superposition of 2n states. This also allows for an immense amount of parallel processing.
• Quantum cryptography is the science of exploiting quantum mechanical properties to perform cryptographic tasks. The best known example of quantum cryptography is quantum key distribution.

 Uses of Quantum Computing

• Artificial Intelligence & Machine Learning: As the number of applications increases, it becomes a challenging task for traditional computers, to match up the accuracy and speed. And, that’s where quantum computing can help in processing through complex problems in very less time.
• Computational Chemistry: The ability for quantum computers to focus on the existence of both 1 and 0 simultaneously could provide immense power to the machine to successfully map the molecules which, in turn, potentially opens opportunities for pharmaceutical research.
• Cybersecurity & Cryptography: Quantum computing with the help of machine learning can help in developing various techniques to combat these cybersecurity threats. Additionally, quantum computing can help in creating encryption methods, also known as, quantum cryptography.
• Financial Modelling: By applying quantum technology to perform these massive and complex calculations, companies can not only improve the quality of the solutions but also reduce the time to develop them.
• Weather Forecasting: Weather forecasting includes several variables to consider, such as air pressure, temperature and air density, which makes it difficult for it to be predicted accurately. Application of quantum machine learning can help in improving pattern recognition, which, in turn, will make it easier for scientists to predict extreme weather events and potentially save thousands of lives a year. With quantum computers, meteorologists will also be able to generate and analyse more detailed climate models, which will provide greater insight into climate change and ways to mitigate it.

Why in News:

• IIT Madras professor, Shweta Agrawal’s work on quantum cryptography has appeared at conferences Eurocrypt 2019 and 2020.

Reference:

1. https://www.thehindu.com/sci-tech/technology/keeping-secrets-in-a-quantum-world-and-going-beyond/article33258829.ece