Is M_{Pl} the Planck mass or the reduced Planck mass?

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SUMMARY

The discussion centers on the ambiguity surrounding the term M_{Pl} in the context of the Planck (CMB) collaboration's observation papers. Participants clarify that M_{Pl} can refer to either the Planck mass or the reduced Planck mass, with the specific value of the Planck mass being 2.176 434 x 10-8 kg as per NIST. It is emphasized that proper notation should distinguish between the two, suggesting the use of a diagonal line through the letters P or Pl for the reduced Planck mass, akin to the notation for reduced Planck's constant.

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  • Knowledge of the Cosmic Microwave Background (CMB) and its significance
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Alpha2021
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What is the value of M_{Pl} used in the Planck (CMB) collaboration's observation papers, such as the one referenced in this link: https://arxiv.org/pdf/1807.06211.pdf. Specifically, I am wondering if it refers to the Planck mass or the reduced Planck mass?
 
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Thanks for your kind reply.
Definition of reduced Planck mass can be found here.
The problem is that M_{Pl} is used in the literature interchangeably as Planck mass or reduced Planck mass. Did you see anywhere in Planck's papers where they define M_{Pl}?
 
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I found in

https://www.cosmos.esa.int/web/planck
> https://www.aanda.org/articles/aa/full_html/2020/09/aa33910-18/aa33910-18.html#S1
1683151818052.png

You may get value of m_pl they use.
 
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Alpha2021 said:
What is the value of M_{Pl} used in the Planck (CMB) collaboration's observation papers, such as the one referenced in this link: https://arxiv.org/pdf/1807.06211.pdf. Specifically, I am wondering if it refers to the Planck mass or the reduced Planck mass?
Better practice, although you are right in asking as some authors are sloppy in their typesetting, is to indicate the reduced Planck mass with diagonal line through the letters P or Pl in the subscript, just as one indicates the reduced Planck's constant with a diagonal link through the symbol "h" for Planck's constant.
 

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