Since this blog is all about time, it might be useful to try and explain what time is. Unfortunately, that is not as easy as it sounds, and it has been the subject of debate between philosophers, theologians and physicists for centuries. The difficulty is we can’t see time, we can’t measure it directly, and we can’t start or stop it. The best we can do is to count regular events. For example we can count days or pendulum swings to indirectly measure the passage of time. However, the earth is both slowing down and wobbling on its axis, meaning the length of a day isn’t as constant as we might hope.
Secondly, the answer to the question “what time is it?” depends on us all agreeing on a known starting point. If the answer is 5pm, then you need to know when 12 noon was to understand the answer. There is no such thing as time without a reference.
This is where the theologians got involved – if a starting point is required, what better than to make it a theologically significant event? Hence the Gregorian calendar is based on years since the birth of Christ, and the Islamic calendar is based on lunar months since the Hijra. Scientists have since determined that neither the earth or moon is particular good timekeeper and now use the atomic resonance of a Caesium atom, but the roots of the modern scientific timescale, UTC, still reflect the starting point defined by the Gregorian calendar.
For further information, a white paper called “What is time?” is available on our website here.
