Talk:1162: Log Scale

Explain xkcd: It's 'cause you're dumb.
Revision as of 15:25, 20 January 2013 by Markozeta (talk | contribs) (Added an algorithim for Knuth Paper Stack Notation.)
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The fictional notation MAY BE a parody of Knuth's up-arrow notation - and uranium MAY BE an effective energy source. By the way, labeling the energy sources just with material name is insufficient: how good energy source is hydrogen? -- Hkmaly (talk) 09:17, 18 January 2013 (UTC)

It has a calorific value of about 150 kJ/gm(much higher when compared to coal,etc.) but is too explosiveGuru-45 (talk) 14:24, 18 January 2013 (UTC)
is it really a parody? (well, probably arrow notation grows much more, here there is just a log log log etc) --.mau. (talk) 14:10, 18 January 2013 (UTC)

It's true that uranium has an extremely high energy density, which is of great importance for mobile power plants; however, nuclear fission has a lot of safety issues, especially for mobile power, which is why it is used only for stationary power plants and large military vessels, such as aircraft carriers and subs.

Hydrogen is pretty good when highly compressed so as to get high energy volume density as well, but that leads to problems too. Also, hydrogen leaks more easily than almost anything else. That is especially a problem for an extremely flammable gas. On the plus side for hydrogen, nothing burns more cleanly.

"The log scale can also be abused to make data look more uniform than it really is, so on a log scale sugar and other materials would look largely equal energy density when they clearly are not."

I think this is missing the point, which I take to be that displaying the data on a log scale would understate the vast difference between uranium and the hydrocarbons/carbohydrates:

           E/m   log(E/m)
sugar      19   1.3  *
coal       24   1.4  *
fat        39   1.6  **
gas        46   1.7  **
uranium   76e6  7.9  ****.***

Uranium is clearly larger than the others, but only by a factor of 4, so the real magnitude of the difference may not be appreciated. With the stack of paper, he's proposing a way to show linear values for the data without having the uranium column simply shooting off the top of the page, with an arrow and the number. Wwoods (talk) 17:26, 18 January 2013 (UTC)

or, he could just print at a scale that allows 76,000,000 to fit on the page, with the other values shown as near-infinitesimally thin lines. 18:23, 18 January 2013 (UTC)

A googolplex in Knuth's paper stack notation (based upon 3818 chr per page, and 25,824 pages to fill up a typical 8ft tall room), would be: 96.41816408 with a 2 pinned on it.

The algorithim is:


y = log10(N)

If y/3818 >= 25824

 Z = Z + 
 z = KnuthPaperStack(y)
 Return z,Z


 Return y,Z

End if

--Markozeta (talk) 15:25, 20 January 2013 (UTC)