What is the Error Range for Planck's Constant in CODATA's Concise Form?

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Discussion Overview

The discussion centers around the error range for Planck's constant as presented in CODATA's concise form, exploring the nature of its measurement and the implications of its uncertainty. The scope includes experimental determination and the interpretation of reported values.

Discussion Character

  • Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • Some participants note that Planck's constant, unlike mathematical constants such as π and e, is an experimental number, and its precision is limited by measurement capabilities.
  • One participant cites the CODATA concise form for Planck's constant as h=6.626 068 76(52) x 10-34 J s, highlighting the reported uncertainty.
  • There is a question regarding the meaning of the parentheses in the reported value, with some suggesting it indicates uncertainty or experimental error.
  • A later reply clarifies that the number in parentheses (52) represents the error in the last digits of the constant, providing a range for h as 6.626 068 24 < h < 6.626 069 28.

Areas of Agreement / Disagreement

Participants generally agree on the nature of Planck's constant as an experimentally determined value with associated uncertainty, but there is some ambiguity regarding the interpretation of the error notation.

Contextual Notes

The discussion does not resolve the broader implications of the uncertainty in Planck's constant or how it affects related calculations or theories.

Who May Find This Useful

Readers interested in experimental physics, measurement theory, or the specifics of fundamental constants may find this discussion relevant.

dav2008
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OK, we all know there's tons of websites that give the digits of Pi and even e...But does anyone know how many digits we know Plancks constant to? Is experimentally the only way to determine it?
 
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Unlike &pi; and e, which are defined mathematically, h and c are experimental numbers so we do not know them to more digits then have been measured. h is sort of self limiting.
 
Last edited:
NIST lists the CODATA concise form for Planck's constant as h=6.626 068 76(52) x 10-34 J s.
 
Hm..Ive seen those parenthesis after constants in my textbook...What do they mean? It says something about like theyre not certain about those digits...is that right?
 
()=uncertainty or experimental error(?)
 
Originally posted by Loren Booda
NIST lists the CODATA concise form for Planck's constant as h=6.626 068 76(52) x 10-34 J s.

The (52) is the error in the last digits, so

6.626 068 24 < h < 6.626 069 28
 

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