Welcome to "What Is Reality?", the site which investigates the very deepest and most profound questions about the nature of physical reality. A series of accessible articles incorporating the latest ideas from theoretical physics, mathematics, cosmology, and philosophy.

Each article may be read individually, though they do link together in sequence.

I've also included examples of my artwork (below).

If you enjoy this site, you will love my new book now available on Amazon.com and Amazon.co.uk.

Andrew Thomas

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Click on the thumbnails for the full image plus detailed explanation.

Venice Wormhole Antibes Inside Out

Quantum Mechanics: An Introduction

Introducing the peculiar world of the quantum, where a particle is a wave, and a wave is a particle. Considers the Heisenberg Uncertainty Principle.
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The Quantum Casino

At its most basic level, nature appears to be fundamentally random. Are we all players in a game of chance at the Quantum Casino?
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Quantum Entanglement

Quantum states can become entangled in astonishing ways. Welcome to the strange world of "qubits", faster-than-light communication, and Einstein's first definition of reality.
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Quantum Decoherence

At last it would appear a solution has been found to the riddle of the apparent collapse of the wavefunction. Includes an interactive simulation of decoherence in an ensemble of particles.
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Reality Is Relative

Everything in the universe must be defined relative to everything else in the universe.
Reveals the common foundations of relativity and quantum mechanics.
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Time and the Block Universe

Using a purely logical argument - involving no physics or mathematics whatsoever - this page might make you change your mind about everything you have ever believed about the passage of time.
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The Arrow of Time

All fundamental physical processes appear to be time-reversible - so why don't we see broken eggs mending themselves? And why can't we remember the future?
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The Anthropic Principle

Some of the fundamental physical constants in the universe appear to have been fine-tuned, otherwise life could not exist. Are "multiverse" solutions the answer to this mystery?
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The Mathematical Universe

The universe appears to have an uncanny connection with the world of mathematics. Why is this? And do mathematical structures have a reality all of their own?
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Is the Universe a Computer?

Some physicists believe the universe behaves like a digital computer. But are there some things in the universe which cannot be computed? And is the universe made of "information"?
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Are We Living in the Matrix?

An examination of the evidence that our universe is the product of an advanced civilisation. Are we living in a computer simulation? Are we all "housemates" in the ultimate reality show?
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The Intelligent Universe

Does intelligence play a special role in the universe? Could the universe have created itself? And could Arnold Schwarzenegger's Terminator arm hold the key?
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