Proper Time
Proper time is the time measured by a clock moving with the object. It is always shorter than coordinate time measured by a stationary observer.
Variables
Derivation
The proper time is an invariant quantity in special relativity.
Your notes
Constants in this formula
Other modern physics formulas with the same quantities
- Relativistic Momentum (Special Relativity) shares Lorentz factor, Velocity, Speed of light
- Length Contraction (Special Relativity) shares Lorentz factor, Speed of light
- Relativistic Total Energy (Special Relativity) shares Lorentz factor, Speed of light
- Relativistic Kinetic Energy (Special Relativity) shares Lorentz factor, Speed of light
- Relativity of Simultaneity (Special Relativity) shares Lorentz factor, Speed of light
- Mass-Energy Equivalence (Special Relativity) shares Speed of light
Where this formula is listed
- Modern Physics formulas, under Special Relativity, alongside Energy-Momentum Relation, Relativistic Velocity Addition and Relativistic Doppler Effect.
- In the modern physics list it comes after Relativistic Doppler Effect and before Relativity of Simultaneity.
- Modern Physics formula sheet, one of 41 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Proper Time formula?
Proper Time is written dτ = dt/γ = dt√(1 − v²/c²). Proper time is the time measured by a clock moving with the object. It is always shorter than coordinate time measured by a stationary observer. It belongs to Modern Physics, under Special Relativity.
What are the units in dτ = dt/γ = dt√(1 − v²/c²)?
In SI units, dτ is proper time interval, measured in s; dt is coordinate time interval, measured in s; γ is lorentz factor (dimensionless); v is velocity, measured in m/s; c is speed of light, measured in m/s.
How is the Proper Time formula derived?
The proper time is an invariant quantity in special relativity. The result is dτ = dt/γ = dt√(1 − v²/c²).