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

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In cgs units, setting c and h-bar to 1 is not standard practice; instead, one should use consistent units throughout. The discussion highlights that in classical electrodynamics (CED), both c and h-bar can be omitted if space and time are treated as interchangeable dimensions, allowing for dimensionless velocity. This approach is similar to methods used in astronomy, where seconds can represent both space and time. It is emphasized that using non-reduced units is necessary for clarity in calculations. Ultimately, maintaining consistent units is crucial for proper application in electrodynamics.
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Using cgs units, can I set c = h-bar =1 ? or should I change some other units to do that?

Thanks
 
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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.
 
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
 
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.
 
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.
 
I tried to answer for hbar, which goes the same way, but it was rejected as a
"duplicate post".
 
Time reversal invariant Hamiltonians must satisfy ##[H,\Theta]=0## where ##\Theta## is time reversal operator. However, in some texts (for example see Many-body Quantum Theory in Condensed Matter Physics an introduction, HENRIK BRUUS and KARSTEN FLENSBERG, Corrected version: 14 January 2016, section 7.1.4) the time reversal invariant condition is introduced as ##H=H^*##. How these two conditions are identical?

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