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

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Discussion Overview

The discussion centers around the possibility of setting the speed of light (c) and the reduced Planck's constant (h-bar) to 1 in cgs units while working on electrodynamics. Participants explore the implications of unit choices and consistency in theoretical frameworks.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant questions whether it is possible to set c = h-bar = 1 in cgs units and asks if other units need to be adjusted.
  • Another participant asserts that if c, h-bar, epsilon 0, and mu 0 are all set to 1, it is acceptable, but questions the use of cgs units in general.
  • A participant clarifies that consistent units can be used without needing to set c and h-bar in cgs units, suggesting that space and time can be treated dimensionally equivalent, thus making c dimensionless.
  • There is a mention of the third edition of Jackson's reference using mKs units, implying a preference for those over cgs.
  • One participant attempts to address the treatment of h-bar similarly but faces a rejection of their post as a duplicate.

Areas of Agreement / Disagreement

Participants express differing views on the necessity of setting c and h-bar to 1 in cgs units, with some arguing for the flexibility of unit choices while others emphasize the need for specific unit systems. The discussion remains unresolved regarding the best approach to unit selection.

Contextual Notes

There are limitations regarding the assumptions made about unit consistency and the implications of using different unit systems (cgs vs. mKs). The discussion does not resolve the mathematical steps or the definitions of the constants involved.

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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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 weird, 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".
 

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