Talk:Planck energy

I think a citation is needed for the claim that the maximum photon energy is the Planck energy. Is this claim based on the shortest photon wavelength allowed being the Planck length? I’m not sure this is so.

Weasel words, and meaningless factoid.

The Planck energy equals approximately the electricity consumed by an average person in a developed country in two weeks (2001 figures for US citizens).

When you say "electricity" what exactly are you referring to? It's generally understood to mean electric current. How do you convert energy (joules) into current (coulombs per second) to make this a meaningful comparison?

If you mean energy, then fucking say energy. "Electricity" is a meaningless word, and has no place in a science article.

Better yet, don't say it at all, because it's wrong and irrelevant. --75.58.54.17 06:53, 28 October 2007 (UTC)[reply]

I agree wholeheartedly, and would like to subscribe to your newsletter and/or mailing list. --76.217.94.0 (talk) 22:34, 11 February 2008 (UTC)[reply]

value in joules

can we safely state the value in joules to slightly more precision than the 1.956E9 J we presently have published? i calculated 1.956084(98)E9 J (about 100 KJ uncertainty vs. 500 KJ implied by sig figs in our published value) - although i am concerned about physical or statistical subtleties of which i am unaware that would make my calculation incorrect or inapplicable.

i used the rules for propagation of uncertainty and the following values for h-bar, c, and G from NIST's website, to calculate the planck energy = sqrt( h-bar * c^5 / G )

h-bar: 1.054571628(53)E-34 J s

c: 299792458 m/s (exact)

G: 6.67428(67)E-11 m^3 kg^-1 s^-2

my intermediate values, copied directly from spreadsheet, are:

c^5 h-bar / G: 3.82626614701424E+18

stddev of c^5 h-bar / G: 384101152450286 = ( c^5 h-bar / G) sqrt( (sigma-of-h-bar / h-bar)^2 + (sigma-of-G / G)^2 )

Michael redman (talk) 05:22, 28 December 2009 (UTC)[reply]

Value in tons of TNT

Even more entertaining, the Planck Energy is half a ton of TNT. 1.956 × 10⁹ J = 0.467 tons of TNT. Pulu (talk) 14:28, 9 December 2010 (UTC)[reply]

Reductions and Normalisations from the Start?

Having studied the subject for quite some time, it occured to me that the complete "Planck world", i.e. all Planck values (and their derivatives) are necessarily wrong, since they all rely on the reduced Planck constant ("h-bar") instead of the true value. Wherever h-bar is used, typically in a square root, the result of the calculation is off by a factor of roughly 2,5. There is no problem introducing reduced constants or some normalisation, once the unchanged constants of nature have been applied. My suggestion is obviously to begin the corresponding articles with the basic calculations, using especially the Planck constant in the original form. Regards, K. Cormann 80.136.3.251 (talk) 12:48, 24 December 2014 (UTC)[reply]

Do we need to discuss "reduced Planck energy"?

While the ultimate energy photon has the Planck energy, I don't understand the physical significance of the reduced Planck energy. I searched with google and didn't turn up any wide usage of "reduced Planck energy". Unless someone has good reason, I propose deleting the sentences about "reduced Planck energy". J Mark Morris (talk) 23:56, 23 May 2019 (UTC)[reply]

Reduced Planck Energy

In the paragraph concerning "Reduced Planck Energy" (which I DO think is a useful quantity to include), the current version includes the following: "In the equations of general relativity, G is often multiplied by 4π. Hence writings in particle physics and physical cosmology often normalize 4πG to 1." This is verifiably incorrect. If one merely consults the pages on General Relativity (https://en.wikipedia.org/wiki/General_relativity) and the Einstein Field Equations (https://en.wikipedia.org/wiki/Einstein_field_equations), one cannot help but notice that normalization most commonly uses 8πG. In fact, an earlier version of this page properly included this normalization factor. I urge that the page be updated and REVERTED to use 8πG in the expressions concerning Reduced Planck Energy". The equation would be updated as follows:

{\sqrt {\frac {\hbar {}c^{5}}{8\pi G}}}\approx 3.90\times 10^{8}\ \mathrm {J} \approx 2.43\times 10^{18}\ \mathrm {GeV} \approx 108.14\ \mathrm {kWh} .

Wesfree (talk) 23:49, 19 January 2020 (UTC)wesfree[reply]