ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

Understanding Temporal Dilation: The Time Vs. Velocity Equation - Part 3

Updated on September 25, 2009

If the speed that the light travels does not change, then something else must change. That something is time. Time is not constant, as hard as that is to imagine. One second for Jenny is not the same as one second for Johnny. Since their perceptions of time are different, that explains the paradox. The faster that Johnny chases after the light, the more that his time slows down, making it impossible for him to catch the light. Johnny's one second is longer than Jenny's one second, so the light has time to catch up to where Johnny thinks it should be after one second.

In order to better understand this, a more realistic example is needed. Johnny's rocket has now become his new hot rod, and Jenny's flashlight is now a stopwatch. They stand on a mile long drag strip. On Jenny's signal Johnny goes zooming down the mile long stretch at 120 miles per hour. After precisely one mile Jenny stops the stopwatch. It reads exactly 30 seconds. Johnny, feeling suspicious about Jenny's measuring ability, had brought along his own watch and timed himself in his car, stopping it exactly at the one mile mark. His watch reads 29.99999999999952 seconds, a tiny bit less than Jenny's watch. They may just brush off the difference as either human or instrumentation error, but, in fact, both watches are correct. Time is not the same for everyone. A person who is moving experiences time more slowly than someone who is standing still. Two people who are moving in relation to each other, like Johnny and Jenny, will not agree on the elapsed time between two events.

The reason that this difference in time is not evident under ordinary conditions, is that we travel at too low of speeds for the effects of the special theory of relativity to have a large enough effect. Remember, the difference in Jenny's and Johnny's time was miniscule, only a tiny fraction of a second. Because the effect of relativity is not normally experienced, it is not intuitive. We do not see its consequences at low speeds, so it seems completely unfathomable to many. In order for there to be a significant affect, the person traveling must be going a large portion of the speed of light. Light travels so fast that it can go around the earth more than seven times every second. Naturally, with present technology it is impossible to achieve those kinds of speeds in everyday life. However, GPS satellites have to be constantly time adjusted as their orbital speed allows for an extremely minute but nonetheless significant discrepancy with the time flow on the surface of the planet.

To better make sense of this remarkable phenomenon, a more profound example is needed, one that in the physics world is known as the "twin paradox." Suzie and Sarah are identical twins. On their twentieth birthday, Sarah has to leave and spend twenty years on a spaceship for some unknown reason. Sarah boards the ship and zips around the galaxy at eighty-seven percent the speed of light, or 580 million miles per hour. Finally, when the twenty years are up, Sarah returns to earth to celebrate her fortieth birthday with her twin. Much to Sarah's surprise, Suzie is celebrating her sixtieth birthday when she returns. While 20 years have passed for Sarah, 40 years have gone by for Suzie. This is because at high speeds time actually slow downs. Einstein thought of space and time as being linked together in a new entity called space-time. Because Sarah, traveling 580 million miles per hour, was exerting so much of her energy in moving through space, little energy was left over to travel through time. Compared to a nearly stationary Suzie, Sarah was living her life in slow motion, at one-half the normal speed.

Continued In: Understanding Temporal Dilation: The Time Vs. Velocity Equation - Part 4

Back To Start


    0 of 8192 characters used
    Post Comment

    No comments yet.


    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at:

    Show Details
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the or domains, for performance and efficiency reasons. (Privacy Policy)
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)