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Modern Physics
Modern Physics

Time Dilation

Δt=γΔt0=Δt01−v2c2\Delta t = \gamma \Delta t_0 = \frac{\Delta t_0}{\sqrt{1 - \frac{v^2}{c^2}}}

Moving clocks run slower. Time measured in the rest frame is shorter than time measured by a moving observer.

Variables

\Delta t
Dilated time (observed)
s
\Delta t_0
Proper time
s
\gamma
Lorentz factor
unitless
v
Relative velocity
m/s
c
Speed of light
m/s

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Common questions

What is the Time Dilation formula?

Time Dilation is written Δt = γΔt₀ = frac{Δt₀}{√(1 - v²/c²)}. Moving clocks run slower. Time measured in the rest frame is shorter than time measured by a moving observer. It belongs to Modern Physics, under Special Relativity.

What are the units in Δt = γΔt₀ = frac{Δt₀}{√(1 - v²/c²)}?

In SI units, \Delta t is dilated time (observed), measured in s; \Delta t_0 is proper time, measured in s; \gamma is lorentz factor (dimensionless); v is relative velocity, measured in m/s; c is speed of light, measured in m/s.