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==Title==
== Potential ==
Should this be moved to [[geometrized unit]] (singular)? Sometimes the plural is appropriate in an article title; is this such a case? [[User:Michael Hardy|Michael Hardy]] 15:46, 18 Dec 2003 (UTC)


as it is now, the two entries "elecitric potential" and "potential" (the very last) are identical. would it not make much more sense to interpret the second potential as gravitational potential? then its SI dimension would be [''L''<sup>2</sup> ''T''<sup>-2</sup>] (the same as energy/mass), and the multiplication factor would just be c<sup>-2</sup>. --[[User:Diogenes2000|Diogenes2000]] ([[User talk:Diogenes2000|talk]]) 02:51, 30 December 2012 (UTC)
I moved it to '''geometrized unit system''', for in this case the plural was used to identify a category. Thanks for the comment.


==Conversion factors between meter, kilogram, second, coulomb and kelvin==
==8&pi;G=1==
Here you have all needed conversion factors that covers all SI base units, and if not possible, their unique elements:
Isn't sometimes 8&pi;G set to 1? --[[User:Pjacobi|Pjacobi]] 11:05, July 31, 2005 (UTC)


into m
:There actually are several different systems involved here. Your "sometimes" and the "sometimes" starting the second paragaph of the article are clues to that fact. [[User:Gene Nygaard|Gene Nygaard]] 11:16, 31 July 2005 (UTC)


*G/c^2 [m/kg]
Yes, 8&pi;G is another common convention, as is 16&pi;G=1. This is problematic. My impression is that the most common modern convention is 8&pi;G=1, but I could be mistaken. &ndash;[[User:Joke137|Joke137]] 18:10, 2 October 2005 (UTC)
*c [m/s]
*((G/(4*pi*(electric constant)))^0.5)/c^2 [m/C]
*(G*k)/c^4 [m/K]


into kg
::But what about Wald, ''General relativity'', Appendix F, which uses c = G =1? This is probably the most widely used graduate textbook on general relativity in the English-speaking world. Can anyone cite a major textbook which used either of the other two conventions mentioned by Joke137? ---[[User:Hillman|CH ]] [[User_talk:Hillman|(talk)]] 01:33, 3 October 2005 (UTC)


*c^2/G [kg/m]
==Students beware==
*c^3/G [kg/s]
I extensively edited the August 2006 version of this article and had been monitoring it for bad edits, but
*1/(G*4*pi*(electric constant))^0.5 [kg/C]
I am leaving the WP and am now abandoning this article to its fate.
*k/c^2 [kg/K]


into s
Just wanted to provide notice that I am only responsible (in part) for the last version I edited; see [[User:Hillman/Archive]]. I emphatically do not vouch for anything you might see in more recent versions, although I hope for the best.


*1/c [s/m]
Good luck in your search for information, regardless!---[[User:Hillman|CH]] 23:52, 30 June 2006 (UTC)
*G/c^3 [s/kg]
*((G/(4*pi*(electric constant)))^0.5)/c^3 [s/C]
*(G*k)/c^5 [s/K]


into C
==MKS charge units==
I believe there should be a entry for converting SI charge units in the official conversion table.


*c^2/((G/(4*pi*(electric constant)))^0.5) [C/m]
Using google calculator, I get for the conversion constant:
*(G*4*pi*(electric constant))^0.5 [C/kg]
*c^3/((G/(4*pi*(electric constant)))^0.5) [C/s]
*(k*(G*4*pi*(electric constant))^0.5)/c^2 [C/K]


into K
<math>\sqrt{G / 4 \pi \epsilon_0 c^4} </math> = sqrt(G / (4 * Pi * electric constant * c^4)) = 8.61667791 × 10-18 m / coulomb


*c^4/(G*k) [K/m]
question: what source should be used for constant values?
*c^2/k [K/kg]
*c^5/(G*k) [K/s]
*c^2/(k*(G*4*pi*(electric constant))^0.5) [K/C]


All these units represents nothing else than distance along dimension, that makes SI redundant in comparison to geometrized units. I added all these abovementioned factors after proper formatting to article. They can be verified in Google calculator.
[[User:Pervect|Pervect]] 23:09, 22 July 2006 (UTC)


This all is exactly equivalent to dividing of one [[Planck unit]] by another [[Planck unit]], while using their direct SI values. [[Special:Contributions/83.30.150.203|83.30.150.203]] ([[User talk:83.30.150.203|talk]]) 08:20, 20 January 2024 (UTC)
==Edits==
I've made the edits indicated above, having gotten no comments. The conversion table from Wald is for cgs units, unfortunately. This would only matter for charge and related electrical units. I've marked up the table to indicate it's a cgs table as the simplest course of action to fix the issue.


== Geometric quantities ==
consistency checks:
:1 statcolumb * sqrt(G)/c^2 -> 2.87 * 10^-25 cm = 2.87* 10^-27 m
:1 coulomb -> 8.62 * 10^-18 m (from MKS table)
:1 statcolumb / 1 coulomb = 3.33*10^-10


I removed an entire section with a table of conversions. @[[User:Anubub|Anubub]] reverted the change, but I took it out again based on [[WP:BURDEN]].
consistent with http://en.wikipedia.org/wiki/Statcoulomb
This is incosistent with the wiki [[cgs]] page, however!


The table entries need a reference. If the entries are trivial, then we don't need the table. If the entries are [[WP:NOTABLE]] then they need a reference.
more consistency checks:


In addition, the practical issue is that entries in the table keep being changed and we have no justification for reverting such changes because we have no reference. [[User:Johnjbarton|Johnjbarton]] ([[User talk:Johnjbarton|talk]]) 16:09, 24 June 2024 (UTC)
:charge of electron = 1.381*10^-34 cm (MTW back cover)
:charge of electron = 1.60*10^-19 coulomb * 8.62*10^-18 m/coulomb = 1.38*10^-36 m = 1.38*10^-34 cm

[[User:Pervect|Pervect]] 22:41, 29 July 2006 (UTC)

==More edits==
I went through and added the SI units and conversion factors to the table (a major edit at least in terms of work).

I cross-checked the conversion formulas for SI units with google calculator. Examples (cut and paste the following formula into google calc). epsilon_0 is "electric constant" in Google.

:(ampere)*(sqrt(G/(4*pi*electric constant)))/c^3=
:(tesla)*(sqrt(G*(4*pi*electric constant))/c)=
:(volt)*(sqrt(G*(4*pi*electric constant))/c^2)=
<!-- Template:Unsigned --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Pervect|Pervect]] ([[User talk:Pervect#top|talk]] • [[Special:Contributions/Pervect|contribs]]) 01:45, 4 August 2006 (UTC)</small>

==Introduction==
Hello Pervect

It seems that the sentence is incomplete:

In situations involving electrical units, we add the constraint that the quantity 4πε<sub>0</sub>, where ε<sub>0</sub> is [[vacuum permittivity]]. [[Special:Contributions/83.30.48.117|83.30.48.117]] ([[User talk:83.30.48.117|talk]]) 18:00, 28 October 2009 (UTC)

as it is now, the two entries "elecitric potential" and "potential" (the very last) are identical. would it not make much more sense to interpret the second potential as gravitational potential? then its SI dimension would be [''L''<sup>2</sup> ''T''<sup>-2</sup>] (the same as energy/mass), and the multiplication factor would just be c<sup>-2</sup>. --[[User:Diogenes2000|Diogenes2000]] ([[User talk:Diogenes2000|talk]]) 02:50, 30 December 2012 (UTC)

== Potential ==

as it is now, the two entries "elecitric potential" and "potential" (the very last) are identical. would it not make much more sense to interpret the second potential as gravitational potential? then its SI dimension would be [''L''<sup>2</sup> ''T''<sup>-2</sup>] (the same as energy/mass), and the multiplication factor would just be c<sup>-2</sup>. --[[User:Diogenes2000|Diogenes2000]] ([[User talk:Diogenes2000|talk]]) 02:51, 30 December 2012 (UTC)

Latest revision as of 19:09, 30 June 2024

Potential

[edit]

as it is now, the two entries "elecitric potential" and "potential" (the very last) are identical. would it not make much more sense to interpret the second potential as gravitational potential? then its SI dimension would be [L2 T-2] (the same as energy/mass), and the multiplication factor would just be c-2. --Diogenes2000 (talk) 02:51, 30 December 2012 (UTC)[reply]

Conversion factors between meter, kilogram, second, coulomb and kelvin

[edit]

Here you have all needed conversion factors that covers all SI base units, and if not possible, their unique elements:

into m

  • G/c^2 [m/kg]
  • c [m/s]
  • ((G/(4*pi*(electric constant)))^0.5)/c^2 [m/C]
  • (G*k)/c^4 [m/K]

into kg

  • c^2/G [kg/m]
  • c^3/G [kg/s]
  • 1/(G*4*pi*(electric constant))^0.5 [kg/C]
  • k/c^2 [kg/K]

into s

  • 1/c [s/m]
  • G/c^3 [s/kg]
  • ((G/(4*pi*(electric constant)))^0.5)/c^3 [s/C]
  • (G*k)/c^5 [s/K]

into C

  • c^2/((G/(4*pi*(electric constant)))^0.5) [C/m]
  • (G*4*pi*(electric constant))^0.5 [C/kg]
  • c^3/((G/(4*pi*(electric constant)))^0.5) [C/s]
  • (k*(G*4*pi*(electric constant))^0.5)/c^2 [C/K]

into K

  • c^4/(G*k) [K/m]
  • c^2/k [K/kg]
  • c^5/(G*k) [K/s]
  • c^2/(k*(G*4*pi*(electric constant))^0.5) [K/C]

All these units represents nothing else than distance along dimension, that makes SI redundant in comparison to geometrized units. I added all these abovementioned factors after proper formatting to article. They can be verified in Google calculator.

This all is exactly equivalent to dividing of one Planck unit by another Planck unit, while using their direct SI values. 83.30.150.203 (talk) 08:20, 20 January 2024 (UTC)[reply]

Geometric quantities

[edit]

I removed an entire section with a table of conversions. @Anubub reverted the change, but I took it out again based on WP:BURDEN.

The table entries need a reference. If the entries are trivial, then we don't need the table. If the entries are WP:NOTABLE then they need a reference.

In addition, the practical issue is that entries in the table keep being changed and we have no justification for reverting such changes because we have no reference. Johnjbarton (talk) 16:09, 24 June 2024 (UTC)[reply]