superposition

The Dog That Said Maybe

By Ron Santos

December 1, 2017

Man's best friend, or man's biggest confusion?

Lithium

By Finbarr O'Reilly

December 1, 2017

Everything is possible. Probably.

Criminal Fringes

By Steven Buczkowski

December 1, 2017

There's a new thief in town, and the police are baffled...

Schrödinger’s Rabbit

By Ashtrof Wyvern

December 1, 2017

Meet the most confusing, adorable and terrifying animal on campus!

Red's forlorn hope

By Rowan Grigg

December 1, 2017

If space calculates, it can't be made of turtles...

The Minefield

By Nikola Couling

December 1, 2017

The mines are a relic of the early days of applied entanglement

Quantum Faith

By Alejandro Figueroa

December 1, 2017

For a moment he imagined himself to be a quantum zombie

Trapped

By Marina Cobal

November 30, 2017

There's a familiar noise outside, a gait slow and attentive, almost suspicious

How Matter Becomes Light

By Elizabeth Stott

November 30, 2017

It was many years ago, but Lily remember the books and the boy who never came back

The Dead-Alive Singularity

By Jesse Kaje

November 30, 2017

Dr. Solomon Eckhart has a strange message to bring...

Quantum Theory: A to Z

B is for ... Bose-Einstein Condensate (BEC)

At extremely low temperatures, quantum rules mean that atoms can come together and behave as if they are one giant super-atom.

M is for ... Many Worlds Theory

Some researchers think the best way to explain the strange characteristics of the quantum world is to allow that each quantum event creates a new universe.

D is for ... Decoherence

Unless it is carefully isolated, a quantum system will “leak” information into its surroundings. This can destroy delicate states such as superposition and entanglement.

W is for ... Wavefunction

The mathematics of quantum theory associates each quantum object with a wavefunction that appears in the Schrödinger equation and gives the probability of finding it in any given state.

U is for ... Uncertainty Principle

One of the most famous ideas in science, this declares that it is impossible to know all the physical attributes of a quantum particle or system simultaneously.

O is for ... Objective reality

Niels Bohr, one of the founding fathers of quantum physics, said there is no such thing as objective reality. All we can talk about, he said, is the results of measurements we make.

J is for ... Josephson Junction

This is a narrow constriction in a ring of superconductor. Current can only move around the ring because of quantum laws; the apparatus provides a neat way to investigate the properties of quantum mechanics.

I is for ... Interferometer

Some of the strangest characteristics of quantum theory can be demonstrated by firing a photon into an interferometer: the device’s output is a pattern that can only be explained by the photon passing simultaneously through two widely-separated slits.

K is for ... Kaon

These are particles that carry a quantum property called strangeness. Some fundamental particles have the property known as charm!

S is for ... Schrödinger Equation

This is the central equation of quantum theory, and describes how any quantum system will behave, and how its observable qualities are likely to manifest in an experiment.

W is for ... Wave-particle duality

It is possible to describe an atom, an electron, or a photon as either a wave or a particle. In reality, they are both: a wave and a particle.

T is for ... Tunnelling

This happens when quantum objects “borrow” energy in order to bypass an obstacle such as a gap in an electrical circuit. It is possible thanks to the uncertainty principle, and enables quantum particles to do things other particles can’t.

H is for ... Hawking Radiation

In 1975, Stephen Hawking showed that the principles of quantum mechanics would mean that a black hole emits a slow stream of particles and would eventually evaporate.

D is for ... Dice

Albert Einstein decided quantum theory couldn’t be right because its reliance on probability means everything is a result of chance. “God doesn’t play dice with the world,” he said.

P is for ... Probability

Quantum mechanics is a probabilistic theory: it does not give definite answers, but only the probability that an experiment will come up with a particular answer. This was the source of Einstein’s objection that God “does not play dice” with the universe.

C is for ... Cryptography

People have been hiding information in messages for millennia, but the quantum world provides a whole new way to do it.

E is for ... Entanglement

When two quantum objects interact, the information they contain becomes shared. This can result in a kind of link between them, where an action performed on one will affect the outcome of an action performed on the other. This “entanglement” applies even if the two particles are half a universe apart.

R is for ... Reality

Since the predictions of quantum theory have been right in every experiment ever done, many researchers think it is the best guide we have to the nature of reality. Unfortunately, that still leaves room for plenty of ideas about what reality really is!

M is for ... Multiverse

Our most successful theories of cosmology suggest that our universe is one of many universes that bubble off from one another. It’s not clear whether it will ever be possible to detect these other universes.

Y is for ... Young's Double Slit Experiment

In 1801, Thomas Young proved light was a wave, and overthrew Newton’s idea that light was a “corpuscle”.

T is for ... Teleportation

Quantum tricks allow a particle to be transported from one location to another without passing through the intervening space – or that’s how it appears. The reality is that the process is more like faxing, where the information held by one particle is written onto a distant particle.

A is for ... Atom

This is the basic building block of matter that creates the world of chemical elements – although it is made up of more fundamental particles.

A is for ... Act of observation

Some people believe this changes everything in the quantum world, even bringing things into existence.

H is for ... Hidden Variables

One school of thought says that the strangeness of quantum theory can be put down to a lack of information; if we could find the “hidden variables” the mysteries would all go away.

L is for ... Light

We used to believe light was a wave, then we discovered it had the properties of a particle that we call a photon. Now we know it, like all elementary quantum objects, is both a wave and a particle!

S is for ... Superposition

Quantum objects can exist in two or more states at once: an electron in superposition, for example, can simultaneously move clockwise and anticlockwise around a ring-shaped conductor.

A is for ... Alice and Bob

In quantum experiments, these are the names traditionally given to the people transmitting and receiving information. In quantum cryptography, an eavesdropper called Eve tries to intercept the information.

R is for ... Randomness

Unpredictability lies at the heart of quantum mechanics. It bothered Einstein, but it also bothers the Dalai Lama.

L is for ... Large Hadron Collider (LHC)

At CERN in Geneva, Switzerland, this machine is smashing apart particles in order to discover their constituent parts and the quantum laws that govern their behaviour.

B is for ... Bell's Theorem

In 1964, John Bell came up with a way of testing whether quantum theory was a true reflection of reality. In 1982, the results came in – and the world has never been the same since!

Q is for ... Qubit

One quantum bit of information is known as a qubit (pronounced Q-bit). The ability of quantum particles to exist in many different states at once means a single quantum object can represent multiple qubits at once, opening up the possibility of extremely fast information processing.

V is for ... Virtual particles

Quantum theory’s uncertainty principle says that since not even empty space can have zero energy, the universe is fizzing with particle-antiparticle pairs that pop in and out of existence. These “virtual” particles are the source of Hawking radiation.

X is for ... X-ray

In 1923 Arthur Compton shone X-rays onto a block of graphite and found that they bounced off with their energy reduced exactly as would be expected if they were composed of particles colliding with electrons in the graphite. This was the first indication of radiation’s particle-like nature.

F is for ... Free Will

Ideas at the heart of quantum theory, to do with randomness and the character of the molecules that make up the physical matter of our brains, lead some researchers to suggest humans can’t have free will.

U is for ... Universe

To many researchers, the universe behaves like a gigantic quantum computer that is busy processing all the information it contains.

G is for ... Gluon

These elementary particles hold together the quarks that lie at the heart of matter.

C is for ... Computing

The rules of the quantum world mean that we can process information much faster than is possible using the computers we use now.

S is for ... Schrödinger’s Cat

A hypothetical experiment in which a cat kept in a closed box can be alive and dead at the same time – as long as nobody lifts the lid to take a look.

N is for ... Nonlocality

When two quantum particles are entangled, it can also be said they are “nonlocal”: their physical proximity does not affect the way their quantum states are linked.

Z is for ... Zero-point energy

Even at absolute zero, the lowest temperature possible, nothing has zero energy. In these conditions, particles and fields are in their lowest energy state, with an energy proportional to Planck’s constant.

Q is for ... Quantum biology

A new and growing field that explores whether many biological processes depend on uniquely quantum processes to work. Under particular scrutiny at the moment are photosynthesis, smell and the navigation of migratory birds.

P is for ... Planck's Constant

This is one of the universal constants of nature, and relates the energy of a single quantum of radiation to its frequency. It is central to quantum theory and appears in many important formulae, including the Schrödinger Equation.

G is for ... Gravity

Our best theory of gravity no longer belongs to Isaac Newton. It’s Einstein’s General Theory of Relativity. There’s just one problem: it is incompatible with quantum theory. The effort to tie the two together provides the greatest challenge to physics in the 21st century.

R is for ... Radioactivity

The atoms of a radioactive substance break apart, emitting particles. It is impossible to predict when the next particle will be emitted as it happens at random. All we can do is give the probability that any particular atom will have decayed by a given time.

I is for ... Information

Many researchers working in quantum theory believe that information is the most fundamental building block of reality.

Read Shorts

An Entangled Love Story

By Sihan Huang

entanglement, physics, love

Inside the Box

By Juliet Wilson

Schrodinger's cat

The Machine

By Nick Maslov

information, quantum teleportation, no cloning

superposition

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