Waves
This dimensionless number compares inertial to elastic forces in wave motion and determines when shallow-water waves become dispersive.
What is the Froude number?
This theorem states that the work done by a potential force equals the negative change in potential energy.
What is the work–energy theorem (for conservative forces)?
These three quarks make up all commonly occurring hadrons.
What are up, down, and strange?
A process with constant entropy is called this.
What is isentropic?
This postulate states that the laws of physics are the same in all inertial frames.
What is the principle of relativity?
These waves on the surface of water rely on surface tension, not gravity, for their restoring force.
What are capillary waves?
This type of motion occurs when a rigid body rolls without slipping, conserving both translational and rotational kinetic energy.
What is pure rolling motion?
This boson gives mass to other Standard Model particles through spontaneous symmetry breaking.
What is the Higgs boson?
This famous inequality states that no engine can be more efficient than a reversible one operating between the same temperatures.
What is the Carnot efficiency inequality?
This metric describes the spacetime around a non-rotating, spherically symmetric mass.
What is the Schwarzschild metric?
This phenomenon occurs when the group velocity of a wave packet exceeds the phase velocity, causing the envelope to move faster than individual peaks.
What is anomalous dispersion?
The Lagrangian formulation uses this quantity defined as L = T - V
What is the Lagrangian?
This quantum number distinguishes matter from antimatter in the weak interaction and is conserved in most processes.
What is lepton number?
The partition function is denoted by this symbol and encodes all equilibrium thermodynamic information of a system.
What is Z?
This effect, measured by GPS satellites, causes clocks higher in a gravitational field to tick faster.
What is gravitational time dilation?
Waves in a plasma oscillate at this characteristic frequency that depends only on electron density.
What is the plasma frequency?
The virial theorem states that for a potential proportional to rn , the average kinetic energy and potential energy satisfy this relation:
What is 2⟨T⟩ = n⟨V⟩?
This process occurs when a particle turns into its own antiparticle—possible only for neutrinos if they are this type of fermion.
What is a Majorana particle (or "What is being Majorana?")
This law of statistical physics states that at high temperatures every quadratic degree of freedom has an average energy of 1/2 kB T?
What is the equipartition theorem?
This relativistic quantity remains invariant for all observers and equals E2 - pc2.
What is the invariant mass (rest mass)?
This equation describes a quantum-mechanical wave packet evolving freely and shows that the packet spreads with time.
What is the Schrödinger equation for a free particle?
This tensor quantifies how mass is distributed relative to an axis and determines rotational response to torque.
What is the inertia tensor?
This deep inelastic-scattering experiment at SLAC gave the first hard evidence for quarks by observing Bjorken scaling.
What is the SLAC e−p scattering experiment (1968–69)?
This paradox in black-hole thermodynamics arises because Hawking radiation gives black holes an entropy proportional to their surface area, not volume.
What is the black hole information paradox?
This solution to Einstein’s equations describes a rotating black hole with frame-dragging and an ergosphere.
What is the Kerr metric?