method

experiment

A scientific procedure undertaken to test a hypothesis or discover an unknown effect.
7 related articles

Description

An experiment is a controlled procedure designed to test a hypothesis, measure a phenomenon, or discover an unknown effect. In physics, experiments are the ultimate arbiter of theory — they confirm predictions, challenge established models, and reveal new phenomena that drive theoretical advances. From Galileo's inclined plane to modern particle colliders, experiments have shaped our understanding of the universe by providing empirical evidence that separates fact from speculation.

History

The modern experimental method was formalized by Francis Bacon in the 17th century and exemplified by Galileo Galilei, who combined systematic observation with mathematical analysis. Since then, experiments have evolved from simple benchtop setups to massive international collaborations like CERN's Large Hadron Collider.

How it works

A well-designed experiment isolates variables, controls conditions, and measures outcomes with precision. It typically involves a hypothesis, a setup that manipulates one or more parameters, and a measurement system that records the results. The data are then analyzed statistically to determine whether the observed effect is real or due to chance, and the results are compared with theoretical predictions to validate or refute the model.

In practice

Experiments are the foundation of all applied physics, from testing new materials for batteries to validating the safety of nuclear reactors and developing medical imaging technologies.

Fun fact

The most expensive experiment in history is the Large Hadron Collider, costing about $4.75 billion, which discovered the Higgs boson in 2012 — a particle predicted 48 years earlier.

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Related articles · 7

How an AI Scientist Taught a Robot Fish to Swim
In the watery environment, vortices batter the mechanical fish. The AI agent, like an experimental chef, ran simulations, tried out 'recipes' of movements, and improved the program. Each experiment was like spectroscopy: the agent broke down behavior into elements, uncovering patterns. At first, the fish only paddled in one direction.
High Energy2026-04-201 minarXiv:2604.18016express
Neutron Star Glitches: Solved in the Lab
A neutron star is a spinning top with the mass of the Sun, crushed to the size of a city. It's born in the fire of a supernova and usually only slows its spin. But sometimes, for no apparent reason, it suddenly speeds up — such a jerk is called a glitch.
Atomic Physics2026-03-241 minarXiv:2603.22981express
All Atoms Fall Alike: A Cosmic Verdict
Galileo, legend has it, dropped balls from the Tower of Pisa to prove that heavy and light objects fall equally. This law formed the foundation of Einstein's theory of gravity. Today, scientists have turned an entire space station into such a tower.
Quantum Physics2025-11-241 minarXiv:2511.19242express
Can gravity entangle particles?
Two particles can become linked so that a nudge on one instantly reverberates in the other, even if they are separated by galaxies. Einstein called it "spooky action at a distance." Physicists wondered: can gravity itself, a simple mutual attraction, create such a connection?
The Shadow of a Measured Value: How the EPR Paradox Dissolves in Operators
In 1935, Einstein, Podolsky, and Rosen proposed a thought experiment that, in their view, exposed the incompleteness of quantum mechanics. Two particles fly apart after interacting, and measuring the momentum of one instantly gives exact knowledge of the other's momentum.
A Bridge from a Single Particle to a Pair: How Existing Experiments Can Prove Quantum Gravity
In 2022, physicists observed gravity shifting the phase of a single atom's wave, the gravitational analog of the Aharonov–Bohm effect. This experiment became part of a long-standing debate: whether gravity must be quantized or remains a classical background in the quantum world.
Quantum Physics2025-06-031 minarXiv:2506.02637express
Pilot droplets: a new look at quantum reality
In the quantum world, particles do not have precise properties until they are measured. The official model refuses to explain what lies behind this uncertainty. But the idea that invisible 'pilots' control particles has been around since the 1920s.