All Physics is a physics reference, online since the early 2000s. It follows no syllabus and awards no certificates. People come here to look something up, to check a value, or to see how a result was reached.
What is here
The encyclopedia — two hundred entries, arranged by letter as in a printed dictionary.
Physicists — over a thousand biographies of the people who built the subject, from Archimedes to Feynman.
The handbook of quantities, physics formulas and the physical constants — what most readers arrive looking for.
Experiments, photographs, video and virtual laboratory experiments — the parts that show physics rather than describe it.
Where the figures come from
Values and dates are taken from published reference works. The physical constants follow CODATA 2022, as published by NIST.
Corrections
A reference is worth exactly as much as it is accurate. If you find an error in a formula, a value or a date, please tell us through the contact form. Every correction is read.