Book contents
- Frontmatter
- Contents
- Preface
- 1Introduction
- 2Why travel to the stars?
- 3Rockets
- 4Orbital mechanics
- 5Thermal rockets
- 6Ion engines
- 7Relativistic motion
- 8Nuclear rockets
- 9Relativistic optical effects
- 10Solar sails
- 11Laser sails
- 12The interstellar medium
- 13Magnetic and electric sails
- 14Navigation
- 15Communication
- 16Payloads
- 17Outlook
- Appendix AFurther reading
- References
- Index
7 - Relativistic motion
Published online by Cambridge University Press: 10 June 2026
Book contents
- Frontmatter
- Contents
- Preface
- 1Introduction
- 2Why travel to the stars?
- 3Rockets
- 4Orbital mechanics
- 5Thermal rockets
- 6Ion engines
- 7Relativistic motion
- 8Nuclear rockets
- 9Relativistic optical effects
- 10Solar sails
- 11Laser sails
- 12The interstellar medium
- 13Magnetic and electric sails
- 14Navigation
- 15Communication
- 16Payloads
- 17Outlook
- Appendix AFurther reading
- References
- Index
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Summary
The special theory of relativity rests on just two axioms: the identity of the laws of physics in all inertial reference frames, and the invariance of the speed of light. After briefly reviewing the basics of special relativity, including the Lorentz transformations and time dilation, we look at the effects of relativity during an accelerated journey. Time dilation has implications even for a spacecraft moving at low velocities. We examine the relativistic rocket equation and then rockets that are propelled by photons or a combination of matter and photons. General relativistic effects are not considered. In a later chapter we look at the impact of relativistic motion on optical phenomena.
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- Chapter
- Information
- The Physics of Interstellar Travel , pp. 93 - 114Publisher: Cambridge University PressPrint publication year: 2026
- Creative Commons
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