# Quick Guide to Quantum Physics: 24 Phenomenons Explained

God does not play dice with the universe

― Albert Einstein

**Quantum Bounce***The Big Bounce is a hypothetical **scientific model** of the formation of the known **universe**. It was originally suggested as a property of the **cyclic model** or oscillatory universe interpretation of the **Big Bang** where the first cosmological event was the result of the collapse of a previous universe*

**Quantum Chaos **

*Quantum chaos is a branch of*

*physics*

*which studies how*

*chaotic*

*classical*

*dynamical systems*

*can be described in terms of*

*quantum theory*

*.*

**Quantum Computation***Quantum computing studies theoretical **computation** systems (quantum computers) that make direct use of **quantum-mechanical** **phenomena**, such as **superposition** and **entanglement**, to perform **operations** on **data**.*

Not only does God play dice but… he sometimes throws them where they cannot be seen

―Stephen Hawking

**Quantum Data Compression***The Quantum compression format is a little-known **data compression** method created by David Stafford.Quantum archive files are named with the **filename extension** **.Q** by convention.*

**Quantum Data Locking (Quantum Enigma Machine)***One of the most promising contemporary applications of quantum mechanics is within cryptography, where the laws of quantum physics certify the secrecy of a communication protocol.*

**Quantum Key Distribution (in Quantum Cryptography)***Quantum key distribution (QKD) uses **quantum mechanics** to guarantee **secure communication**. It enables two parties to produce a shared **random** secret **key** known only to them, which can then be used to encrypt and decrypt **messages**.*

**Quantum ****Decoherence***In **quantum mechanics**, **quantum decoherence** is the loss of **coherence** or ordering of the **phase angles** between the components of a system in a **quantum superposition**.*

I am now convinced that theoretical physics is actually philosophy

— Max Born

**Quantum Dense Coding (Superdense Coding)***In **quantum information theory**, **superdense coding** is a technique used to send two bits of classical information using only one **qubit**.**[1]**[2]** It is the inverse of **quantum teleportation**, which sends one qubit with two classical bits.*

**Quantum Steering**

*Steering can occur in strongly entangled systems and implies a direction between the two parties involved, while entanglement without steering generally has no direction.*

**Quantum Entanglement***Quantum entanglement is a physical phenomenon that occurs when pairs or groups of **particles** are generated or interact in ways such that the **quantum state** of each particle cannot be described independently — instead, a quantum state may be given for the system as a whole.*

We are thus forced to conclude that the quantum-mechanical description of physical reality given by wave functions is not complete

— Einstein, Podolsky, Rosen Paradox

**Quantum Illumination**

*Quantum illumination is a technique to use*

*quantum entanglement*

*beneficially even if the original entanglement is completely destroyed by a lossy and noisy environment.*

**Quantum Interference (Quantum Diffraction)***In **physics**, **interference** is a phenomenon in which two **waves** **superpose** to form a resultant wave of greater or lower **amplitude**.*

**Quantum Jumps (+method)***Electrons transition instantaneously between energy levels within an atom all at a random time*

**Quantum Noise (Quantum Uncertainty)***In **physics**, quantum noise refers to the uncertainty of a physical quantity that is due to its quantum origin.*

**Quantum Non-Demolition Measurement***Quantum nondemolition (QND) measurement is a special type of **measurement** of a **quantum** system in which the uncertainty of the measured **observable** does not increase from its measured value during the subsequent normal evolution of the system.*

I am a Quantum Engineer, but on Sundays I Have Principles

―John Stewart Bell

**Quantum Nonlocality**

*In*

*theoretical physics*

*, quantum nonlocality is the phenomenon by which measurements made at a microscopic level contradict a collection of notions known as local realism that are regarded as intuitively true in*

*classical mechanics*

*.*

**Quantum One-Time Pad**

*In*

*cryptography*

*, the one-time pad (OTP) is an*

*encryption*

*technique that cannot be*

*cracked*

*if used correctly. In this technique, a*

*plaintext*

*is paired with a random secret*

*key*

*. The same method knows as QOTP can be applied in*

*quantum cryptography*

*using quantum key exchange*

**Quantum State Tomography***Quantum **tomography** or quantum state tomography is the process of reconstructing the **quantum state** (**density matrix**) for a source of quantum systems by measurements on the systems coming from the source*

**Quantum Superposition***Quantum superposition is a fundamental principle of **quantum mechanics**. It states that much like waves in **classical physics**, any two (or more) quantum states can be added together (“superposed”) and the result will be another valid quantum state; and conversely, that every quantum state can be represented as a sum of two or more other distinct states.*

**Quantum Teleportation**

*Quantum teleportation is a process by which quantum information (e.g. the exact state of an atom or photon) can be transmitted (exactly, in principle) from one location to another, with the help of*

*classical communication*

*and previously shared*

*quantum entanglement*

*between the sending and receiving location.*

**Quantum Tunneling**

*Quantum tunnelling or tunneling (see*

*spelling differences*

*) refers to the*

*quantum mechanical*

*phenomenon where a particle tunnels through a*

*barrier*

*that it*

*classically*

*could not surmount. This plays an essential role in several physical phenomena, such as the*

*nuclear fusion*

*that occurs in*

*main sequence*

*stars like the*

*Sun*

**Quantum Uncertainty (of the irreducible variety)***In **quantum mechanics**, the uncertainty principle, also known as Heisenberg’s uncertainty principle, is any of a variety of mathematical inequalities asserting a fundamental limit to the precision with which certain pairs of physical properties of a particle, known as **complementary** variables, such as **position** x and **momentum** p, can be known simultaneously.*

What we observe is not nature itself, but nature exposed to our method of questioning

— Werner Karl Heisenberg

**Quantum Wave-Particle Duality (Quantum Interference) ***Wave–particle duality is the fact that every **elementary particle** or **quantic** entity exhibits the properties of not only **particles**, but also waves. It addresses the inability of the classical concepts “particle” or “wave” to fully describe the behavior of quantum-scale objects.*

**Quantum Zero-Point Energy***Zero-point energy, also called quantum vacuum zero-point energy, is the lowest possible **energy** that a **quantum mechanical** **physical system** may have; it is the energy of its **ground state**.*

Quantum physics thus reveals a basic oneness of the universe.— Erwin Schrodinger