Special & General Relativity Questions and Answers
What is the fourth dimension?
It is generally recognized that the 4th dimension is the parameter we call 'time'. What time itself is, we have no idea. It is simply a parameter of nature that we need to organize many kinds of data. Temperature, spin, charge, mass are also other 'dimensions' commonly used in physics and we may equally say that these are physical dimensions too!
Return to the Special & General Relativity Questions and Answers page.
All answers are provided by Dr. Sten Odenwald (Raytheon STX) for the NASA Astronomy Cafe, part of the NASA Education and Public Outreach program.