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This is a list of physical laws discovered by science. Bolded items are categories for the entries indented underneath instead of individual laws.

• Boyle's Law (pressure and volume of ideal gas)
• Charles & Gay-Lussac (gases expand equally with the same change of temperature)
• Ideal Gas Law
• Dulong-Petit law (specific heat capacity at constant volume)

  ${\displaystyle c_{V}={\frac {3R}{M}}}$

Einstein

• Energy of photons - Energy equals Planck's constant multiplied by the frequency of the light.

  E = hν

Special Relativity

• Constancy of the speed of light
• Lorentz transformations - Transformations of Cartesian coordinates between relatively moving reference frames.

  ${\displaystyle x'=(x-vt)/{\sqrt {1-v^{2}/c^{2}}}}$

  ${\displaystyle y'=y}$

  ${\displaystyle z'=z}$

  ${\displaystyle t'=(t-vx/c^{2})/{\sqrt {1-v^{2}/c^{2}}}}$

• Law of force - Force equals mass times acceleration divided by the square root of one minus the ratio squared of the object's velocity to the speed of light.

  ${\displaystyle F=ma/{\sqrt {1-v^{2}/c^{2}}}}$

• Mass-energy equivalence

  ${\displaystyle E=mc^{2}}$ (Energy = mass × speed of light)

General Relativity

• Energy-momentum (including mass via E=mc) curves spacetime.

  This is described by the Einstein field equations:

  ${\displaystyle R_{ab}-{1 \over 2}R\,g_{ab}={8\pi G \over c^{4}}T_{ab}.}$

  ${\displaystyle R_{ab}}$ is the Ricci tensor, ${\displaystyle R}$ is the Ricci scalar, ${\displaystyle g_{ab}}$ is the metric tensor, ${\displaystyle T_{ab}}$ is the stress-energy tensor, and the constant is given in terms of ${\displaystyle \pi }$ (pi), ${\displaystyle c}$ (the speed of light) and ${\displaystyle G}$ (the gravitational constant).

• Laws of Kepler (planetary motion)
• Beer-Lambert (light absorption)

Newton

• Newton's laws of motion - Replaced with relativity

  *1. Law of Inertia

  *2. F = ma Force equals mass times acceleration.

  *3. ${\displaystyle F_{ab}=-F_{ba}}$ Force of a on b equals the negative force of b on a, or for every action there is an equal and opposite reaction.

• Law of heat conduction
• General law of gravitation - Gravitational force between two objects equals the gravitational constant times the product of the masses divided by the distance between them squared.

  ${\displaystyle F_{g}=G{\frac {m_{1}m_{2}}{r^{2}}}}$

  This law is really just the low limit solution of Einstein's field equations and is not accurate with modern high precision gravitational measurements.

• Coulomb's law - Force between any two charges is equal to the absolute value of the multiple of the charges divided by 4 pi times the vacuum permittivity times the distance squared between the two charges.

${\displaystyle F={\frac {\left|q_{1}q_{2}\right|}{4\pi \epsilon _{0}r^{2}}}}$

• Ohm's Law

${\displaystyle V=IR}$

• Kirchhoff's circuit laws (current and voltage laws)
• Kirchhoff's law of thermal radiation
• Maxwell's equations (electric and magnetic fields):

Name Partial Differential form Gauss's law : ${\displaystyle \nabla \cdot \mathbf {D} =\rho }$ Gauss's law for magnetism: ${\displaystyle \nabla \cdot \mathbf {B} =0}$ Faraday's law of induction: ${\displaystyle \nabla \times \mathbf {E} =-{\frac {\partial \mathbf {B} }{\partial t}}}$ Ampere's law + Maxwell's extension: ${\displaystyle \nabla \times \mathbf {H} =\mathbf {J} +{\frac {\partial \mathbf {D} }{\partial t}}}$

• Navier-Stokes equations of fluid dynamics

${\displaystyle -\nabla p+\mu \left(\nabla ^{2}\mathbf {u} +{1 \over 3}\nabla (\nabla \cdot \mathbf {u} )\right)+\rho \mathbf {u} =\rho \left({\partial \mathbf {u} \over \partial t}+\mathbf {u} \cdot \nabla \mathbf {u} \right)}$

• Poiseuille's law (voluminal laminar stationary flow of incompressible uniform viscous liquid through a cylindrical tube with the constant circular cross-section)

${\displaystyle \Phi _{V}={\pi r^{4} \over 8\eta }{\triangle p^{\star } \over l}}$

Radiation laws

• Planck's law of black body radiation (spectral density in a radiation of a black-body)
• Wien's law (wavelength of the peak of the emission of a black body) :λ₀T = k_w
• Stefan-Boltzmann law (total radiation from a black body)

  ${\displaystyle j^{\star }=\sigma T^{4}}$

Thermodynamics

• first law of thermodynamics
• second law of thermodynamics
• third law of thermodynamics
• Onsager reciprocal relations - sometimes called the Fourth Law of Thermodynamics

  ${\displaystyle \mathbf {J} _{u}=L_{uu}\,\nabla (1/T)-L_{ur}\,\nabla (m/T)\!}$; and

  ${\displaystyle \mathbf {J} _{r}=L_{ru}\,\nabla (1/T)-L_{rr}\,\nabla (m/T)\!}$.

• Buys-Ballot's law (wind travels counterclockwise around low pressure systems in the Northern Hemisphere)

Quantum Mechanics

• Heisenberg Uncertainty Principle - Uncertainty in position multiplied by uncertainty in momentum is equal to or greater than Dirac's constant divided by 2.

  ${\displaystyle \Delta x\Delta p\geq {\frac {\hbar }{2}}}$

• Schrodinger equation - Describes the time dependence of a quantum mechanical system.

  ${\displaystyle H(t)\left|\psi (t)\right\rangle =i\hbar {\partial \over \partial t}\left|\psi (t)\right\rangle }$

  The Hamiltonian H(t) is a self-adjoint operator acting on the state space, ${\displaystyle \psi (t)}$ is the instantaneous state vector at time t, i is the unit imaginary number, ${\displaystyle \hbar }$ is Planck's constant divided by 2π

It is thought that the successful integration of Einstein's field equations with the uncertainty principle and Schrodinger equation, something no one has achieved so far with a testable theory, will lead to a theory of quantum gravity, the most basic physical law sought after today.

See also

• Scientific laws named after people

• Science lists