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BC/AD Problems

  1. Mar 2, 2010 #1
    Hi everyone,
    i really dont understand the philosophy of BC/AD notations..
    but i only know the order goes like this:
    ....., 3 BC, 2 BC, 1 BC, 1 AD, 2 AD, 3AD, .....
    Now in which year we are now...
    when we say 2010, will it mean 2010 AD??
    Why historians always prefer to say in BC AD notations, which is really confusion for me??
    this confusion i have from my childhood!
    thanks
     
  2. jcsd
  3. Mar 2, 2010 #2

    Evo

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    Staff: Mentor

    It's based on the Gregorian calendar which is the most widely accepted in the western world. It is based on Jesus and BC stands for "before christ" and AD stands for "Anno Domini". to confuse things more, BC and AD have been replaced with the more secular BCE (before common era) and CE (Common Era).

    Here is a more detailed explanation.

    http://en.wikipedia.org/wiki/Anno_Domini
     
  4. Mar 2, 2010 #3
    Well you can also switch to the geologic notation: BP (Before Present) and 'present' being 1950 AD :tongue:
     
  5. Mar 2, 2010 #4
    Ok,
    Evo, that means 500 BC = before (2010+500) years.
    and
    10 AD= before (2010-10) years.
    Is this correct..
    I also prefer the BP notations..
     
  6. Mar 2, 2010 #5

    Evo

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    Staff: Mentor

    That's correct. It's more or less an imaginary line in the calendar, just remember there is no zero year, it goes from 1 BC to 1 AD.
     
  7. Mar 2, 2010 #6
    and that why the new millineum didn't actually start until 2001--not 2000
     
  8. Mar 2, 2010 #7

    BobG

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    Science Advisor
    Homework Helper

    If you're figuring out how many years, probably close enough.

    But technically, it should be 500 BC is 2509 years ago

    (2010+500-1) since there's no year zero
     
  9. Mar 2, 2010 #8
    wouldn't it be 2508?

    since there was no +0 or -0?
     
    Last edited: Mar 2, 2010
  10. Mar 2, 2010 #9
    Bobg,
    as evo said no '0'..so i understand it..
    thanks to all
     
  11. Mar 2, 2010 #10

    f95toli

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    Gold Member

    There is actually a zero year in one of the systems (there are two).
    E.g. astronomers do at times use a year zero, whereas historians don't....

    Just to make things extra confusing...
     
  12. Mar 2, 2010 #11

    Evo

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    Staff: Mentor

    But not in the Gregorian calendar.
     
  13. Mar 2, 2010 #12
    Wasn't there a movement in Europe a long while ago that tried to create a whole new system of dates? Time, day, month, year.
     
  14. Mar 2, 2010 #13
    yeah, some goofy decimal system, I think


    here's something interesting to think about:

    how many days apart are Jan 1 500 BC and Dec 31 501 BC; or Jan 1 500 BC and Dec 31 499 BC?


    In other words, if the years go backward in the BC period, do the months and days also? What day does the New Year begin? Jan 1, or Dec 31?
     
  15. Mar 2, 2010 #14

    Evo

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    Staff: Mentor

    Last edited: Mar 2, 2010
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