Introduction to Quantum Mechanics and Quantum Dynamics

Mihirsinh Chauhan
3 min readSep 1


Introduction to Quantum Dynamics

Welcome to your first day of the #Quantum30 day challenge. Here we understand Quantum Dynamics for Quantum Computing with QuTip. Well those who don’t know QuTiP is open-source software for simulating the dynamics of open quantum systems. We will explore more about it in future blogs. Today we start with exploring the fascinating world of quantum mechanics and quantum dynamics! In this blog, we’ll embark on a journey to understand the fundamental principles that underpin quantum mechanics, laying the foundation for quantum dynamics. Don’t worry if this is your first encounter with these concepts; we’ll break them down step by step.

Double Slit Experiment

Quantum Mechanics: The Basics

At its core, quantum mechanics is a branch of physics that deals with the behavior of matter and energy at the smallest scales — typically, at the level of atoms and subatomic particles. Classical physics, which describes the macroscopic world, doesn’t hold up at these tiny scales. Quantum mechanics provides a new framework for understanding the behavior of these particles.

Key Concepts in Quantum Mechanics:

  1. Quantization: Quantum mechanics introduces a fundamental departure from classical physics: quantization. This means that certain properties, like energy levels, can only exist in discrete, distinct values, unlike the continuous range we’re accustomed to in classical physics.
  2. Wave-Particle Duality: Perhaps one of the most intriguing aspects of quantum mechanics is the idea of wave-particle duality. It suggests that particles, such as electrons and photons, can exhibit both wave-like and particle-like behaviors, depending on how they’re observed or measured.
  3. Heisenberg’s Uncertainty Principle: Proposed by Werner Heisenberg, this principle states that “you cannot simultaneously know the exact position and momentum of a particle with absolute certainty.” The more precisely you measure one of these properties, the less precisely you can know the other. This inherent uncertainty is a fundamental aspect of the quantum world.

Example: The Double-Slit Experiment

To illustrate the concept of wave-particle duality, let’s consider the famous double-slit experiment. Imagine you have a barrier with two slits and you shine a beam of particles, like electrons, at it. In classical physics, you’d expect to see two bands of particles on the other side, corresponding to each slit. However, in the quantum world, electrons behave like waves, creating an interference pattern on the screen behind the slits, much like ripples in water when two sets of waves overlap. This experiment vividly demonstrates the dual nature of quantum particles.

Quantum Dynamics: Understanding Time Evolution

Now that we have a grasp of some basic quantum concepts, let’s introduce the concept of quantum dynamics. Quantum dynamics is all about how quantum systems change over time, and it’s crucial to understand quantum computing.

The Schrödinger Equation: The Quantum Clockwork

At the heart of quantum dynamics is the Schrödinger equation, named after physicist Erwin Schrödinger. It is essentially the “quantum clockwork,” telling us how quantum states evolve in time.

Here’s the equation:

iħ ∂Ψ/∂t = ĤΨ

  • Ψ represents the quantum state of the system.
  • ħ is the reduced Planck's constant, a fundamental constant in quantum mechanics.
  • ∂Ψ/∂t represents the rate of change of the quantum state concerning time.
  • Ĥ is the Hamiltonian operator, which encodes the energy of the quantum system.

What the Schrödinger Equation Tells Us:

In simple terms, the Schrödinger equation tells us how the quantum state Ψ evolves over time. By solving this equation, we can predict the future state of a quantum system based on its current state and the energy operator Ĥ


Today, we’ve embarked on a fascinating journey into the world of quantum mechanics and quantum dynamics. We’ve covered fundamental concepts like quantization, wave-particle duality, and Heisenberg’s uncertainty principle. We’ve also introduced the Schrödinger equation, a powerful tool for understanding how quantum systems change over time.

In the days ahead, we’ll explore these concepts further and see how they connect to the world of quantum computing. Keep in mind that quantum mechanics might challenge our classical intuitions, but it opens up a world of exciting possibilities for computation, simulation, and discovery. Stay curious and keep exploring!

#Day1 of #Quantum30 day challenge. QuantumComputingIndia



Mihirsinh Chauhan

《Quantum computing Enthusiast |Future Innovator》《Under grad at SVNIT | ML| Buisness Amateur》