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

In summary, the conversation revolves around the use of cgs units and whether or not c and h-bar can be set equal to 1. The individual asking the question is working on electrodynamics and is referencing Jackson's 2nd edition, which uses cgs units. The other person explains that in cgs units, c and h-bar do not need to be included as they are dimensionless. They also mention that in astronomy, it is common to use the same unit for both space and time, making c irrelevant.
  • #1
Physicist
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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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  • #2
Nope.epsilon 0,mu 0,c and eitch bar made 1.

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

Daniel.
 
  • #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
 
  • #4
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.
 
  • #5
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.
 
  • #6
I tried to answer for hbar, which goes the same way, but it was rejected as a
"duplicate post".
 

1. Can I set c=h-bar=1 in all equations when using cgs units?

Yes, setting c=h-bar=1 is a common practice in cgs units. This is known as the "natural units" system, where fundamental constants are set to 1 to simplify calculations.

2. How does setting c=h-bar=1 affect the units of measurement in cgs?

When c=h-bar=1, all units of measurement in cgs will be expressed in terms of these fundamental constants. For example, length will be measured in terms of seconds instead of centimeters, and mass will be measured in terms of energy instead of grams.

3. Are there any limitations to using c=h-bar=1 in cgs units?

There are no inherent limitations to using c=h-bar=1 in cgs units. However, it may not be practical or convenient for all scientific applications. Some equations may become more complicated or less intuitive when using natural units.

4. Can I convert from cgs units with c=h-bar=1 to other unit systems?

Yes, it is possible to convert from cgs units with c=h-bar=1 to other unit systems. However, the conversion factors will be different from the conventional cgs units, so it may require additional calculations.

5. How does setting c=h-bar=1 impact the physical interpretation of equations?

Setting c=h-bar=1 does not change the physical interpretation of equations. The values and relationships of physical quantities remain the same, but the units of measurement become more simplified and may have different numerical values.

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