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Using cgs units, can I set c=h-bar=1?

  1. May 21, 2005 #1
    Using cgs units, can I set c = h-bar =1 ? or should I change some other units to do that?

    Thanks
     
  2. jcsd
  3. May 21, 2005 #2

    dextercioby

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    Nope.epsilon 0,mu 0,c and eitch bar made 1.

    BTW,why are u using cgs units in the first place...?

    Daniel.
     
  4. May 21, 2005 #3
    I'm working on electrodynamics and most of the references used cgs, including Jackson (2nd edition).

    So you mean I can't? Or it'll be OK if I put epsilon 0,mu 0,c and eitch bar also 1?

    Thanks
     
  5. May 21, 2005 #4

    dextercioby

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    Nope,unfortunately,CED must be made in nonreduced units,either cgs or mKs.

    Alright,have it your way,but the 3-rd edition of Jackson has mKs units.

    Daniel.
     
  6. May 23, 2005 #5

    Meir Achuz

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    You do not need c and hbar in cgs units, if you use consistent units.
    SR tells us that space and time are just different directions in space-time.
    You can use the unit second for both space and time, and then velocity is dimensionless and there is no c. (You don't even have to set it equal to one.
    It just never appears.) If this sounds wierd, just think of astronomy, where this has been done for many years. You could also use the unit cm for both space and time.
    Then c becomes a conversion constant between th etwo units, just like 5,280.
     
  7. May 23, 2005 #6

    Meir Achuz

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    I tried to answer for hbar, which goes the same way, but it was rejected as a
    "duplicate post".
     
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