Let us take a break from classical computing which consists of two only states i.e., 0 and 1. The computing spaceship is compelling us to take a detour and understand quantum computing. The nature and world around us is not purely classical in nature. It has been well proven by various studies that nature can be represented with the help of more than two classical states. ‘The limitation of our intellectual ability to understand nature’ is a caveat to accept the world around us with more than two states. Yes, that’s the key to quantum, if one can acknowledge state of nature beyond two classical states, one can build on nature and achieve the quantum computing paradigm.

The wait is over! The other state which researchers found in nature basis quantum physics, is known as superposition. What quantum physics postulates is that, nature is not that simple to understand, it can be in one more state other than the two classical states. For example, a state between spin up or down for an electron or in between on/off for a bit. It is proven that sub-atomic particles exist in superposition state, which is described by quantum mechanics, i.e. the mathematical language of quantum. If we somehow are able to control this state of superposition for our computing, we may get many more states with large systems to solve quandaries which classical computers are not able to solve efficiently or at all. When you search global search engines, million analogies will pop up to explain this new state, the most famous one is the story of ‘Schrodinger’s cat’ in a box with a bomb, intuitively it explains superposition as a concept.

The next concept in line is the term entanglement. For this, I have a marvel story to narrate as follows. “Iron Man (IM) and Captain America (CA) are best friends but living on different planets. They have a common teacher as Hulk who can do interstellar travel via jumping planet to planet, whenever he asks any question to (IM) on planet 1 and to (CA) on planet 2, they respond with same answer and it is always wrong; for example, what is the colour of hulk when he gets angry, and they would reply ‘PINK’. They are always harmonized without any interaction” This is entanglement! What does it mean for computing? When sub-atomic particles are in a superposition state, they are entangled with each other i.e., any measurement on one will affect the other. But entangled states in the form of spin, etc. provides us with one more state to be baked in our chips; i.e. transistors. With this, we may have exponential entangled states which can be used for faster computing and solving problems which we are unable to solve via classical computing.

What are these problems which we are not able to solve at all or still searching for efficient methods? The menu is long, but few imperative items on it are integer factorization, simulation of complex chemical compounds, travelling Pokémon, optimal internet shopping, testing primality for large numbers, n-queens reloaded, count the leaves on earth, etc. Discovering solutions to these problems with help of quantum states, may emerge to be ground breaking for humanity when it comes to leapfrogging to build the next era of computing.

Now, let’s explore how quantum computing intertwines with cyber security. The cyber security galaxy is going to be shaken up, when quantum computing gets realized efficiently. The modern cryptography algorithms will break as they are primarily based on methods such as integer factorization, i.e. likes of RSA, SSL may cease to exist with quantum algorithms breaking them in few seconds. At the same time, control over superposition randomness is going to be the cornerstone to build a new galaxy of cyber security with emergence of quantum cryptography.

The expedition to achieve full scale quantum computing is not a cake walk. Researches and work is ongoing in the following fields, but not limited to, quantum search, quantum algorithms, hardware based on ions, electrons, superconducting material, eliminating quantum noise, defining quantum information theory, realizing quantum simulation and deciphering all classes of computational complexities.

I would like to end this quantum piece with a philosophical question for readers to ponder upon. Let us suppose, if we manage to build a nontrivial quantum computer; would that demonstrate, humans may become God with control on sub-atomic particles of nature and even prove existence of parallel universes with the realization of time travel. The irony is ‘Time will Tell!’

Join us at Annual Information Security Summit (AISS) 2018 to explore more interesting discussions over Quantum Computing. Register Now https://aiss2018.dsci.in/