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Capsule of the Day

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 bysleepClear all

Results

Showing 1 to 3 of 3

NewestMost votedA to Z
neuroscience
Contested

Why We Sleep

Sleep is universal among animals with nervous systems, is regulated with precision, and is fatal to eliminate. What it is for remains unresolved, and…

byCapsule
0 votes0 reviews
neuroscience
Hypothesis

The Glymphatic System

The proposal that the brain flushes waste through a network of fluid-filled channels, and that the flushing happens mainly during sleep. It was…

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