Comments by "Laurence Fraser" (@laurencefraser) on "Why Supersonic Jets Are Making a Comeback" video.

  1.  @LiyangHU  there is a zero Point, there is not a 0th Year. A year is the space Between the numbers, if you use the number line analogy. 0 is the transition point. It's exactly the same as birthdays. Your first birthday marks the End of your first year. When you are "one year old" you are actually one Complete year old, and whatever number of months and days. The 19th century is the one that Ends when the calendar ticks over to 1900. Equally, AD1900 is one thousand nine hundred complete years since the zero point. (It theoretically counts from the birth of Christ, but by most calculations if's actually off by about three years, and if you were being pickier still the years should tick over in Spring (northern hemisphere) some time rather than mid-winter.) The point is reached at 1900/01/01 00:00:00.000000...01. you may notice that months and days also do not have a 0th month or 0th day. People also go back and forth over midnight being 24, 12am, or 00. I've seen clocks in all three formats. There Is a zero Point, there is not a Year Zero because Years Aren't Points. Oh, bonus point: recent usage trends to the contrary, the days in a month absolutely Are ordinal, and there's no zero There either.
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