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In the last blog we have studied about the measurement. If you have not gone through it do it soon as this part is indirectly linked with it and we will be keep on referencing it. So What is Bloch sphere and what is its significance in the Quantum world? The Bloch sphere is a representation of qubit states as dots on a unit sphere's surface.The Bloch sphere image may succinctly depict several operations on single qubits that are widely employed in quantum information processing. We can write any normalised(pure) state as: $|\psi\rangle = cos{\theta \over2}|0\rangle + e^{i\psi}sin{\theta\over2}|1\rangle $ where $\psi \in [0,2\pi)$ describe the relative phase and $\theta \in [0,\pi]$ determines the probability to measure $|0\rangle \Big/ |1\rangle$  so, $P(0) = cos^2{\theta \over2}$ $P(1) = sin^2{\theta \over2} $ So basically, all pure state can be illustrated on the surface of sphere with radius $|\vec{r}|=1$, which we call the Bloch sphere .  The coordinate of any sta

In the last blog we learnt about Dirac notation, classical and quantum qubit, if you have not checked it read that first then only you can understand. Link here .  We know how to measure a classical bit but yet we don't know how a quantum bit work and previously stated once we measure, we loose the superposition. So how can we measure if we really loose superposition.  So we use orthogonal bases to describe and measure quantum state. Orthogonal means perpendicular basis a shift of $\pi$ . Let us explore further, doing a measurement onto the basis $(|0\rangle , |1\rangle)$ , the state will collapse either into state $|0\rangle$ or $|1\rangle$ as these are the eigen states of $\sigma_{z}$, we call this a z-measurement. Don't worry if you do not understand, it is bit confusing at first, but once you start using it you will be more familiar. in the last blog we have already known about $|0\rangle \ and \ |1\rangle$. Now we will study about two more basis $(|+\rangle, |-\rangle)$ an

For many people, quantum computing is a brand-new area. But the real question is if it is truly new.  We hear the quantum terms in many Hollywood movies, whenever character are not able to answer any question they give it a fancy term quantum. This ill practices gives hope to many learner including me. However, we feel duped when we approach this profession having learned about a notion and then seeing it in action. Image by Gerd Altmann from Pixabay Quantum computing is a fascinating topic, but it is nothing like what is depicted in movies. It is both simpler and more complicated at a times. Or, to put it another way, it's a superposition of simpler and more complicated.  What makes quantum differ from classical, In classical mechanics any state can be shown by classical bit either 0 and 1. But in case of quantum Mechanics any state can be in superposition. What it means, it can be both in 0 and 1 simultaneously.  If you're familiar with parallel computing, it's whe