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DebunkedThe PolygraphThe instrument popularly called a lie detector, which records breathing, blood pressure, pulse and skin conductance dur…

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The library

Capsules

1,028 capsules, each one classified by the strength of its evidence.

All1,028Fact599Proven130Theory89Hypothesis71Contested90Debunked48
geography236biology88physics67history54medicine45astronomy33psychology26mathematics26chemistry20engineering20astrophysics19neuroscience19anthropology18art18
Filtered byProvenClear all

Results

Showing 21 to 40 of 130

NewestMost votedA to Z
mathematics
Proven

The Four Colour Theorem

Four colours suffice to colour any map so that no two regions sharing a border have the same colour. It was conjectured in 1852, resisted proof for…

byCapsule
0 votes0 reviews
economics
Proven

The Nash Equilibrium

A situation in which no participant can do better by changing strategy alone. It is the central solution concept in game theory, it exists in every…

byCapsule0 votes0 reviews
physics
Proven

X-rays

A form of light too energetic to see, discovered by accident in 1895, which passes through flesh and is stopped by bone. Within months it was in…

byCapsule0 votes0 reviews
biology
Proven

Nitrogen Fixation

Air is nearly eighty percent nitrogen and almost nothing can use it. Breaking the bond that holds the molecule together is what makes proteins and…

byCapsule0 votes0 reviews
biology
Proven

Apoptosis

Cells kill themselves on instruction, following a controlled programme that dismantles them tidily. It builds bodies by removing what is not needed,…

byCapsule0 votes0 reviews
neuroscience
Proven

Long-Term Potentiation

A brief burst of activity at a synapse can strengthen it for hours, days or longer. It is the best-supported cellular mechanism for learning, it was…

byCapsule0 votes0 reviews
neuroscience
Proven

Colour Vision

Colour is not a property of light. It is what the visual system computes from the responses of three receptor types, and the computation is what…

byCapsule0 votes0 reviews
biology
Proven

Circadian Rhythms

Almost every organism runs an internal clock with a period of about a day, generated by a molecular feedback loop inside individual cells. It runs…

byCapsule0 votes0 reviews
biotechnology
Proven

The Polymerase Chain Reaction

A method for making billions of copies of a chosen stretch of DNA from a starting sample too small to work with. It made genetic testing, forensic…

byCapsule0 votes0 reviews
molecular biology
Proven

DNA Replication

Copying a genome of three billion letters, at a final error rate of about one in a billion, in a few hours, every time a cell divides. The mechanism…

byCapsule0 votes0 reviews
mathematics
Proven

Non-Euclidean Geometry

For two thousand years one of Euclid's assumptions looked like it should be provable from the others. It is not. Denying it produces consistent…

byCapsule0 votes0 reviews
mathematics
Proven

Bayes' Theorem

A rule for updating a belief when new evidence arrives. It is a short piece of algebra, it is not in any dispute, and misapplying it produces some of…

byCapsule0 votes0 reviews
mathematics
Proven

The Fourier Transform

Any signal can be decomposed into a sum of pure sine waves of different frequencies. The claim was disbelieved when made, it is one of the most…

byCapsule0 votes0 reviews
physics
Proven

The Hall Effect

Pass a current through a conductor in a magnetic field and a voltage appears across it, perpendicular to both. Discovered by a graduate student in…

byCapsule0 votes0 reviews
physics
Proven

The Ideal Gas Law

One equation relating the pressure, volume, temperature and quantity of a gas. It is an approximation that no real gas obeys exactly, it is accurate…

byCapsule0 votes0 reviews
microbiology
Proven

Pasteurisation

Heating a liquid to a controlled temperature for a controlled time kills enough pathogens to make it safe without destroying it. It is among the most…

byCapsule0 votes0 reviews
computer science
Proven

Error-Correcting Codes

Adding structured redundancy to a message so that errors introduced in storage or transmission can be detected and repaired without asking for a…

byCapsule0 votes0 reviews
medicine
Proven

Semmelweis and Handwashing

A Hungarian obstetrician worked out in 1847 that doctors were killing women in childbirth by carrying something on their hands from the dissection…

byCapsule0 votes0 reviews
chemistry
Proven

Spectroscopy

Every element absorbs and emits light at a unique set of wavelengths. Reading those wavelengths identifies what something is made of without touching…

byCapsule0 votes0 reviews
astronomy
Proven

The Expansion of the Universe

Distant galaxies recede from us, and the further away they are the faster they go. The observation established that the universe has a history rather…

byCapsule0 votes0 reviews
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