# What is Quantum Physics ? Quantum Physics Basics

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**What is Quantum Physics ? Quantum Physics Basics.**

We came from school to our home or we drive from jobs to our home. Look around there are many things having shape, size, and volume or mostly called an 3D object.

There are stuff like bus, car or cycle moves around the city. While traveling we find many vehicle surpassing us or moving in the road at a particular speed. Sometimes, the massive busses slow down their speed, while the other moment they're at the peak.

The regulations in their speed is due to present of mobs in their path.

While driving at a high speed if we do not slow down our vehicle, at a point where required, chances begin for a crash. It's because there present laws of physics in our universe.

Our classical physics work in a way that if we don't follow this, it'll bring destruction for us. There also limitations in physics, sometimes one concepts possible to occur where it's also block other theory.

And these is what the physics we experience in our daily life.

**Also Read: What is Antimatter? What Antimatter is Made of?**
Now, moving to quantum physics we need to understand the basic of quantum mechanics.

### What is Quantum Physics?

The smallest particle in the universe is atom. But, deep inside atom there contain many particles through which it's made off. Such as, electron, proton and neutron. However, our modern science found there may present others particles like Hig boson in an atom.

If we look at the universe, everything is made up of such microscopic particles, you, me, and anything else all are formed due to combination of such small particles.

The study of physics considering microscopic particles is called Quantum physics, Quantum Mechanics or Quantum theory. There also contains laws of physics in the quantum world.

Classical Physics separates to the dimension of particles and atoms. It's been conceivable made by the creation of another mechanical assembly that empowered the presentation of estimations in tiny particles like atoms.

We've two upsets in the manner we saw the physical world in the twentieth century: relativity and quantum mechanics.

Quantum mechanics was conceived in 1924, through crafted by Einstein, Rutherford and Bohr, SchrÃ¶dinger and Heisenberg, Born, Dirac, and numerous others. The standards of quantum mechanics that were found at that point are equivalent to we know them today.

They've turned into the system for considering the vast majority of the wonders that physicists contemplate, from basic frameworks like iotas, particles, and cores to progressively intriguing ones, similar to neutron stars, superfluids, and basic particles.

It's settled today that quantum mechanics, as different hypotheses, has two viewpoints: the numerical and theoretical.

In the primary viewpoint, it's a predictable and exquisite hypothesis and has been monstrously fruitful in clarifying and foreseeing a huge number of nuclear and subatomic wonders.

**Also Read: Do parallel universe exist? 5 Evidence And Theory**
However, in the second one, it has been a subject of unlimited talks without concurred ends. In reality, without quantum mechanics, it was difficult to comprehend the gigantic wonders in quantum mechanics, which does not show up in our naturally visible world.

In this unending method for accomplishment for quantum mechanics, arithmetic, particularly scientific material science created to help quantum mechanics.

To be effective in quantum physics, physicists ought to be proficient mathematicians. Although, quantum physics made easy to explain some paradox in quantum science. There are many concept in quantum physics which you can learn further.

A person do not know alphabet of English, and if he had sent to write English article in writing competition, how would it look. This is similar with the Quantum Mechanics, there present quantum physics basics that need to learn before high level quantum theory.

To understand the principle quantum mechanics you must learn the basics of it. If you want to study quantum mechanics, there are some of the concepts you should clear first. After the knowledge of these concepts you are prepared to learn higher levels of studies in quantum physics.

The topics or the concepts to clear first are are given below.

### 1) PLANCK'S QUANTUM THEORY

1.1 Photons

1.2 De Broglie Waves

1.3 Atoms

1.4 Measurement

The uncertainty principle

Measurement and wave±particle duality

1.2 De Broglie Waves

1.3 Atoms

1.4 Measurement

The uncertainty principle

Measurement and wave±particle duality

### 2) THE SCHROÃˆ DINGER EQUATION

2.1 Waves

Sinusoidal waves

Linear superpositions of sinusoidal waves

Dispersive and non-dispersive waves

2.2 Particle Wave Equations

A wave equation for a free particle

Wave equation for a particle in a potential energy field

### 3) POSITION AND MOMENTUM

3.1 Probability

Discrete random variables

Continuous random variables

3.2 Position Probabilities

Two-slit interference

The Born interpretation of the wave function 3.3 Momentum Probabilities

3.4 A Particle in a Box

3.5 Expectation Values

Operators

Uncertainties

3.6 Quantum States

### 4) ENERGY AND TIME

4.1 The Hamiltonian Operator

4.2 Normal Modes of a String

4.3 States of Certain Energy

4.4 A Particle in a Box

A one-dimensional box

A three-dimensional box

4.5 States of Uncertain Energy

Basis functions

Energy probability amplitudes

4.6 Time Dependence

### 5) SQUARE WELLS AND BARRIERS

5.1 Bound and Unbound States

Bound states

Unbound states

General implications

5.2 Barrier Penetration

Stationary state analysis of reflection and transmission

Tunnelling through wide barriers

Tunnelling electrons

Tunnelling protons

### 6) THE HARMONIC OSCILLATOR

6.1 The Classical Oscillator

6.2 The Quantum Oscillator

6.3 Quantum States

Stationary states

Non-stationary states

6.4 Diatomic Molecules

6.5 Three-dimensional Oscillators

6.6 The Oscillator Eigenvalue Problem

The ground state

Excited states

Is E0 really the lowest energy?

Mathematical properties of the oscillator eigenfunctions

### 7) OBSERVABLES AND OPERATORS

7.1 Essential Properties

7.2 Position and Momentum

Eigenfunctions for position

Eigenfunctions for momentum

Delta function normalization

7.3 Compatible Observables

7.4 Commutators

A particle in one dimension

A particle in three dimensions

7.5 Constants of Motion

### 8) ANGULAR MOMENTUM

8.1 Angular Momentum Basics

8.2 Magnetic Moments

Classical magnets

Quantum magnets

Magnetic energies and the Stern±Gerlac experiment

8.3 Orbital Angular Momentum

Classical orbital angular momentum

Quantum orbital angular momentum

Angular shape of wave functions

Spherical harmonics

Linear superposition

### 9) THE HYDROGEN ATOM

9.1 Central Potentials

Classical mechanics of a particle in a central potential

Quantum mechanics of a particle in a central potential

9.2 Quantum Mechanics of the Hydrogen Atom

Energy levels and eigenfunctions

9.3 Sizes and Shapes

9.4 Radiative Transitions

9.5 The Reduced Mass Effect

9.6 Relativistic Effects

### 10) IDENTICAL PARTICLES

10.1 Exchange Symmetry

10.2 Physical Consequences

10.3 Exchange Symmetry with Spin

10.4 Bosons and Fermions

### 11) ATOMS

11.1 Atomic Quantum States

The central field approximation

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