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Time of 12:00 midnight

  1. Apr 10, 2007 #1
    K.. sorry i didn't search and don't know if this was already a thread. At the time of 12:00 midnight.. EXACTLY.. what day is it.. Say it was 11:59 on monday then 12:00.. 12:00 exactly, not 1 value over it.. say time like froze on 12:00 precisely.. would it be monday or tuesday???
     
  2. jcsd
  3. Apr 10, 2007 #2
    There is just a 2nd order discontinuity in the day name.
     
  4. Apr 10, 2007 #3

    Integral

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    Well since 11:59:59.999 (for any finite number of 9s) is Monday PM clearly 12:00:00.000 AM is Tuesday.
     
  5. Apr 10, 2007 #4
    no... that means a day is not 24 hours but 23:59.99999999999999999999
     
  6. Apr 10, 2007 #5

    Integral

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    That is why I said for a FINITE number of nines. An infinite number as you imply is 12:00 since .999... =1
     
  7. Apr 10, 2007 #6
    LOL

    The message you have entered is too short. Please lengthen your to at least 10 characters.
     
  8. Apr 10, 2007 #7
    yes
    a day is 23:59.99999999999999999999999999999999999999999999999999999999999 hours long
    but what is smallest physical meaning of time:it is 10 to the power (-23) seconds, beyond that time has no physical meaning[in fact this time is equal to the time taken by a particle travelling at the speed of c to crosss a nucleus).
    So it is just same as 24 hours.

    Keep Smiling
    Malay
     
  9. Apr 10, 2007 #8
    More seriously: Monday 12:00 p.m. is the same instant as Tuesday 00:00 a.m. And yes, at this precise instant it is Monday AND Tuesday. Happily this ambiguous situation lasts only 0 seconds.
     
  10. Apr 10, 2007 #9

    Integral

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    Unfortunatly for this argurment 12PM is noon. Just a fraction of a second after 11:59:59 AM
     
  11. Apr 10, 2007 #10
    Well the problem is the same with 12:00 (noon). Noon is not ante-meridiem nor post meridiem is just meridiem. Then 12h (noon) is neither am nor pm.
    I can rewrite the same post in the European way to write the time:
    More seriously: Monday 24:00 is the same instant as Tuesday 00:00. And yes, at this precise instant it is Monday AND Tuesday. Happily this ambiguous situation lasts only 0 seconds.
    Is it better this way PF mentor?
     
  12. Apr 10, 2007 #11

    Integral

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    I don't see that way, Seems straight forward, clearly 12:00:01am is Tuesday. So why is it so difficult to assign 12:00 am to Tuesday?
     
  13. Apr 10, 2007 #12
  14. Apr 10, 2007 #13

    Hootenanny

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    And perhaps you should read this;
     
  15. Apr 10, 2007 #14
    I see. I think inutile to continue this argument.
     
  16. Apr 10, 2007 #15

    D H

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    This question is analogous to asking whether zero is positive or negative. Zero is the boundary between positive and negative but zero itself is neither positive or negative. Similarly, midnight and noon are neither AM nor PM. They are midnight and noon.

    From http://www.physics.nist.gov/News/Releases/questions.html
    Are noon and midnight 12 a.m. or 12 p.m.?

    This is perhaps the trickiest time question of them all. The best answer is that the terms 12 a.m. and 12 p.m. cause confusion and should not be used.
    To illustrate this, consider that "a.m." and "p.m." are abbreviations for "ante meridiem" and "post meridiem." They mean "before noon" and "after noon," respectively. Of course, noon is neither before nor after noon; it is simply noon.
     
  17. Apr 10, 2007 #16
    When accuracy matters, the 24-hour clock should be used, otherwise "noon" and "midnight" are a better fit than 12 AM/PM which is undefined. But since "Tuesday at midnight" can be either morning or evening then Tuesday at 00:00 or Tuesday at 24:00 makes the difference clear. Once again, the 24-hour clock saves the day.
     
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