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Library of Past Questions


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  • Check out the resource links. These are the sites we often point to in answering your questions.
  • Browse through the library of questions below.

Resources for this Topic

  1. General Relativity (

  2. Special Relativity (

  3. Usenet Physics Frequently Asked Questions List (

  4. Ned Wright's Relativity Tutorial (

Library of Past Questions and Answers


  1. Can you recommend web sites that discuss space time?

  2. Have General Relativity and Special Relativity been proven?

  3. What evidence is there that supports the theory of curved space?

  4. Is gravity just warped space-time?

    Traveling at Light Speed

  1. Why is it not possible to travel at the speed of light?

  2. Can you answer my question about energy, space travelers, and relativity?

  3. Does anyone have an analysis of time dilation that I could read?

  4. Has time dilation been detected in controlled experiments?

  5. What is the Twin Paradox in Special Relativity and how is it resolved?

    The Behavior of Light

  1. Do photons have mass ?

  2. If photons have no mass, how are they affected by gravity?

  3. If I were traveling at the speed of light, and turned on a flashlight, would it illuminate my console, or will the light "stall"?

  4. In gravitational lensing, why do off-centered objects appear as multiple images instead of ellipses?

  5. Why is the velocity of light the max speed despite its dependence on the permeability and dielectric constants?

  6. What do recent "faster than light" experiments imply for relativity?

  7. Are gravitational lenes achromatic?

    Energy-Mass Conversion

  1. What does E=mc2 mean?

  2. Why is it impossible, at this point in time, to convert energy into matter?


  1. How fast do gravity waves travel?

  2. Could distant spacecrafts be used for gravity wave detection?

  3. How does antimatter react to gravity of normal matter?

    Relativity and Quantum Physics

  1. What is a graviton?

  2. What are the experimental difficulties in 'discovering' gravitons?

  3. Does Quantum Uncertainty apply in Relativistic effects?

    Hypothetical Questions

  1. Will humans ever be able to time travel?

  2. How can one prove the existence of tachyons and once proven, can they be implemented for space travel?

  3. Could you explain the relativity of theoretical travel through a worm hole?

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