Experimental physics

Main thing

Experimental physics is a branch of physics that focuses on observing and measuring physical phenomena through experiments to test theories and gain insights into the properties and behavior of matter and energy.
Experimental physicists design and conduct experiments to gather empirical data about the universe at various scales, from subatomic particles to astronomical objects. They work closely with theoretical physicists in a symbiotic relationship, where experimentalists provide data to be analyzed and understood, while theorists offer explanations and predictions to guide the design of new experiments.
An example of experimental physics in real life is the Large Hadron Collider (LHC) at CERN, where physicists conduct experiments to study the fundamental particles and forces of nature.

Terms

• Physics – the natural science that studies matter, energy, and their interactions. Example: studying the motion of objects under the influence of forces.

• Theoretical physics – a branch of physics that focuses on developing mathematical models and theories to explain and predict physical phenomena. Example: developing the theory of relativity to describe gravity and spacetime.

• Empirical data – information gathered through observation, measurement, and experimentation. Example: measuring the speed of light.

• Physical phenomena – observable events or occurrences in the physical world. Example: the motion of planets in the solar system.

• Subatomic particles – particles smaller than an atom, such as electrons, protons, and neutrons. Example: studying the behavior of quarks in particle accelerators.

• Astronomical objects – objects in the universe, such as stars, planets, and galaxies. Example: observing the gravitational waves from colliding black holes.

An analogy

Experimental physics is like being a forensic scientist at a crime scene. Just as a forensic scientist collects evidence and analyzes it to reconstruct what happened, an experimental physicist designs experiments to gather data and analyze the results to understand the underlying physical principles at work. In this analogy, theoretical physics is like a detective who tries to explain the crime based on the evidence collected by the forensic scientist.
An example of this analogy in real life is the discovery of the Higgs boson at the LHC, where experimental physicists collected data and analyzed it to find evidence of the particle's existence, while theoretical physicists used this evidence to confirm and refine their theories about the fundamental forces of nature.

A main misconception

Many people believe that experimental physics is just about conducting experiments in a lab.
However, experimental physics involves a wide range of activities, including designing experiments, developing new instruments and techniques, analyzing data, collaborating with theorists, and communicating results to the scientific community and the public. An example of this misconception is the idea that experimental physicists only work with lab equipment, when in reality, they may also work with large-scale facilities like particle accelerators or telescopes.

The history

1. Ancient times (before 1600): Early observations of natural phenomena by philosophers like Aristotle and Archimedes. While not strictly experimental physics, these observations laid the foundation for the development of the scientific method.

2. Scientific Revolution (1600-1700s): Development of the scientific method and early experiments by Galileo Galilei and Isaac Newton.

3. Classical physics (1700s-1900): Experiments in mechanics, thermodynamics, and electromagnetism by scientists like Michael Faraday and James Clerk Maxwell.

4. Modern physics (1900-present): Experiments in relativity, quantum mechanics, and particle physics by physicists like Ernest Rutherford, Marie Curie, and Richard Feynman.

"Experiment is the sole judge of scientific 'truth'." - Richard Feynman, renowned theoretical physicist famous for his work on quantum electrodynamics and particle physics.

Three cases how to use it right now

1. A high school student interested in physics can conduct simple experiments at home, such as measuring the acceleration due to gravity using a pendulum or investigating the properties of light using a laser pointer and a diffraction grating. By doing so, they can gain hands-on experience with the scientific method and develop a deeper understanding of physical concepts.

2. A medical researcher can use experimental physics techniques to study the properties of biological materials, such as the elasticity of skin or the electrical conductivity of neurons. By applying physics principles to biological systems, they can develop new diagnostic tools and therapeutic approaches for various diseases.

3. An engineer working on renewable energy can use experimental physics to optimize the design of solar cells or wind turbines. By conducting experiments to measure the efficiency of different materials and configurations, they can improve the performance and cost-effectiveness of these technologies, contributing to the transition to a more sustainable future.

Interesting facts

• The double-slit experiment, first conducted by Thomas Young in 1801, demonstrated the wave-particle duality of light and laid the foundation for quantum mechanics.

• The Michelson-Morley experiment in 1887 showed that the speed of light is constant in all inertial reference frames, paving the way for Einstein's special relativity.

• The Large Hadron Collider (LHC) at CERN is the world's largest and most powerful particle accelerator, with a circumference of 27 kilometers (16.8 miles).

• The LIGO (Laser Interferometer Gravitational-Wave Observatory) experiment detected gravitational waves for the first time in 2015, confirming a major prediction of Einstein's general relativity.

• The Hubble Space Telescope, launched in 1990, has made over 1.4 million observations and helped astronomers measure the age and expansion of the universe.