Time Dilation Calculator

The effects of travelling at the Speed of light on time

Danny Cohen

Agenda

  1. Introduction: Why time dilation ?
  2. Example scenario
  3. Using the Time Dilation Calculator

1. Introduction: Why time dilation ?

  • According to theory of relativity, traveling at any speed (compared to a startionary observer) casues time to dilate from the perspective of the observer
  • This time dilation effect exists at all speeds, but is undetectable at small speed
  • As the traveling speed increases the time dilation effect becomes more noticeable
  • The following equation calculates the time dilation, relative to traveling speed:


Time Dilation Equation
Source: https://www.pinterest.com/pin/69876231694436244

2. Example scenario

  • The classic example: consider twin bothers -
    • One twin (the stationary observer) remains on Earth, while the other twin (the traveler) boards a spacecraft that travels at a certain percentage of the speed of light.
    • After traveling for a certain period of time at a certain speed, the traveler returns to Earth and reunites with the stationary observer twin
  • Assuming the traveler travels at 80% of the speed of light, for a duration of 10 years, the resulting time dilation calculation and effect is as follows:
speedOfLight <- 299792458 / 1000 # speed of light in vacuum (In Kilometers Per Second) 
percent <- 0.8; years <- 10
travelingSpeed <- percent * speedOfLight
timeDilationFactor <- (1 / sqrt(1 - (travelingSpeed^2 / speedOfLight^2) ))
durationFromStationaryObserverPerspective <- timeDilationFactor * years
sprintf("Elasped years from stationary observer perspective: %1$1.2f", durationFromStationaryObserverPerspective)
## [1] "Elasped years from stationary observer perspective: 16.67"

3. Using the Time Dilation Calculator

  • The calculator requires two input parameters (visualized as sliders):
    1. Traveling speed (as a % of the speed of light in a vacuum)
    2. Duration of travel (in years, from the perspective of the traveler)
  • The X axis of the graph illustrates the input of the speed as a percent of the speed of light
    • (0 to 99.9, since 100% of the speed of light is not calculable)
  • The Y axis of the graph displays the server-side calculated time dilation factor
    • (i.e. how much time dilates from the perspective of the stationary observer compared to the traveler)


Link: ShinyApps.io Time Dilation Calculator