The Meaning of Natural Units: $c=1$

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Discussion Overview

The discussion revolves around the concept of natural units, specifically the implications of setting the speed of light, $c$, to 1. Participants explore the meaning of this frame of reference, the definition of natural units, and their purpose in calculations. The conversation also touches on related topics, including the potential for confusion in using these units and a tangential question about quantum mechanics.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Meta-discussion

Main Points Raised

  • Some participants propose that a frame of reference where $c=1$ indicates that units of distance and time are defined such that $c$ equals 1, such as using years for time and lightyears for distance.
  • There is a distinction made between natural units and other systems where $c=1$, with some participants asserting that while natural units always have $c=1$, not all systems with $c=1 qualify as natural units.
  • Participants inquire about the specific systems of natural units, mentioning the common formulation of $G=c=h=1$ and questioning if this is the definition.
  • Some argue that the primary purpose of using natural units is to simplify calculations, while others suggest there may be additional implications or purposes that are not fully explored.
  • One participant expresses concern that using natural units carelessly can lead to confusion and misdirection.
  • A separate thread of discussion emerges regarding the nature of quantum mechanics, with participants noting that the questions posed are vague and suggesting that more specific inquiries would yield better responses.

Areas of Agreement / Disagreement

Participants generally agree on the definition of natural units and the simplification they provide in calculations. However, there is no consensus on whether there are additional purposes beyond simplification, and the discussion about quantum mechanics remains unresolved and somewhat tangential.

Contextual Notes

Some limitations include the lack of clarity on what constitutes a natural unit system beyond the common definitions, as well as the unresolved nature of the questions regarding quantum mechanics, which diverges from the main topic.

Casco
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What is the meaning of a frame of reference where $c=1$ ?

Are these the so called natural units??

And which is the purpose of this??
 
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Casco said:
What is the meaning of a frame of reference where $c=1$ ?
It just means that your units of distance and time are such that c=1 in that system of units. E.g. if you measure time in years and distance in lightyears.

Casco said:
Are these the so called natural units??
Natural units always have c=1, but not all systems where c=1 are natural units.

Casco said:
And which is the purpose of this??
It makes calculations easier.
 
DaleSpam said:
Natural units always have c=1, but not all systems where c=1 are natural units.

Can you tell me which is the system of natural units?? Because I have seen G=c=h=1, Is it that??
And, its purpose is just making calculations easier or is it there something else besides that?
 
Casco said:
Can you tell me which is the system of natural units?? Because I have seen G=c=h=1, Is it that??
And, its purpose is just making calculations easier or is it there something else besides that?
There is no purpose other than making calculations easier:
http://en.wikipedia.org/wiki/Natural_units
http://en.wikipedia.org/wiki/Planck_units
http://en.wikipedia.org/wiki/Heaviside–Lorentz_units
http://en.wikipedia.org/wiki/Stoney_units
http://en.wikipedia.org/wiki/Atomic_units
http://en.wikipedia.org/wiki/Geometrized_unit_system
 
Ok, thanks.
 
It's also a way cause confusion and misdirection when used carelessly.

As to you opening equation: there aren't any inerital frames of reference with v=c.
 
what actually quantum mechanics means? what is it trying to convince us?what is its application?
 
Hi shana parveen, welcome to PF!

You probably should post a new thread in the QM sub-forum. This question is fine, but it is off topic for both this thread and this sub-forum. Follow this link
https://www.physicsforums.com/forumdisplay.php?f=62

And click the button labeled "New Topic".
 
DaleSpam said:
This question is fine

Actually, I consider it to be extremely vague. I suggest that shana parveen post questions that are more specific, if he hopes to get useful answers.
 
  • #10
shana parveen said:
what actually quantum mechanics means? what is it trying to convince us?what is its application?

I think these are really hard questions to answer, Feynman sad "You don't understand QM, you just get used to it", What is trying to convince us? Very vague question. And its applications are infinities.
 

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