This website contains information on the physical process of time dilation. This phenomenon is a result of special relativity and general relativity, both of which were discovered by the physicist Albert Einstein.

Time Dilation has many strange and mind binding impacts on our view of reality. It allows the progression of time to vary depending on your velocity relative to another observer and/or the strength of the gravitational field you are in.

This change in the progression of time means that it allows something or someone to travel through time. The idea of time travel has long been a fantasy of great literary minds and, after Einstein’s discoveries, it is now a question of when, not if.

The pages in this site will cover the background and history behind Einstein’s discoveries; an explanation of the science and proofs (when not too advanced) of the Mathematics underpinning the science; and finally a look at the practical uses of the science and how it affects us in the real world.



About the Author

This website was created by William Astill for the first year course “Frontiers of Modern Physics”, as part of the degree MPhys Theoretical Physics (Research Placement) which he is currently reading for at the University of Sussex.

About the Site

This site is broken down into three main areas. These are “Special Relativity,” “General Relativity,” and “Further Reading.”

The section “Special Relativity” looks at what is the theory of special relativity, how this theory causes time dilation, examples of how this effect occurs in nature and how we could one day harness time dilation for ourselves.

The section “General Relativity” looks at what is the general theory of relativity, how this theory causes time dilation and its impact on the technology we use in our day to day lives.

The section “Further Reading” contains links to other sources of information for those interested readers along with TV documentaries which have looked at the material contained within this site.

Sources used in the site

The main reference text used in this website is chapter 37 of “University Physics” 12 edition by Young and Freedman, ISBN 13: 978-0321501318. As well as this textbook I have also used web sites for additional reading. Under each heading on the pages in this site will be a list of any websites I have used to supplement the text book for that section. Except where stated the content of this site is my own interpretation and explanation of the content within the textbook and additional websites as cited for each section.

Any images, videos or diagrams not of my own work have had their source acknowledged and, where appropriate, the ownership of any copyright on the material.

For certain sections the textbook wasn’t used and these sections are identified at the top underneath the section’s heading.

If no additional websites are listed then only the textbook was used.