It’s All About Power

Part 3 of World Build­ing for Sci­ence fiction:

This is the def­i­n­i­tion of the Kar­da­shev Scale.  Since it is a mea­sure of the pow­er gen­er­at­ed by a civ­i­liza­tion, it is titled: All about Power.

In case you’ve missed the pre­vi­ous posts in the thread, Part 1 begins here.

The pre­vi­ous post in this thread, Part 2 is here.

 

The Kardashev Scale

The Kar­da­shev scale mea­sures the tech­nol­o­gy of a civ­i­liza­tion.  It express­es the details in one para­me­ter: the pow­er gen­er­at­ed by the civ­i­liza­tion. The pow­er deliv­ered to the Earth from the Sun (approx­i­mate­ly 10¹⁶ W) is equiv­a­lent to 1 on the scale.  We call this a type I civ­i­liza­tion.  Since the pow­er lev­el is plan­e­tary equiv­a­lent, a type I civ­i­liza­tion refers to a plan­e­tary civilization.

The type II civ­i­liza­tion results in num­ber 2 that gen­er­ates the ener­gy from a typ­i­cal star (10²⁶ W).  Anoth­er ten bil­lion times more pow­er is the equiv­a­lent of a small galaxy.  This type III civ­i­liza­tion has num­ber 3 on the Kar­da­shev scale.  The cur­rent lev­el of human­i­ty is about 0.7 on the scale.  (We pro­vide the detailed math­e­mat­ics of the Kar­da­shev scale here.)

An advanc­ing civ­i­liza­tion gen­er­ates more pow­er. This means it can build big­ger things.  Ani­mal pow­er allowed human­i­ty to grow more food. Excess pow­er evolved into a trans­porta­tion sys­tem that dis­trib­uted goods to larg­er dis­tances.  This is true for advance­ments over the his­to­ry of humanity.

In Science Fiction

For our sci­ence fic­tion world build­ing, we assume that the same.  Admit­ted­ly, there are oth­er means of mea­sur­ing the tech­nol­o­gy of a civ­i­liza­tion.  For instance, sci­ence fic­tion role-play­ing games use a dif­fer­ent scale of tech lev­el.  Some use the capa­bil­i­ties of the com­put­ers, oth­ers use the capa­bil­i­ties of the faster-than-light star dri­ve as the mea­sure.  The Kar­da­shev scale pro­vides a means to scale all of these mea­sures to the pow­er gen­er­at­ed by the civilization.

We expand on the idea to make anoth­er def­i­n­i­tion.  We define a scale of pow­er per indi­vid­ual.  This scale shows that a Type I civ­i­liza­tion and rough­ly Earth pop­u­la­tion has about 1 MW per indi­vid­ual.  We set this lev­el 0 on this new scale.  Pos­i­tive num­bers show more pow­er per indi­vid­ual and neg­a­tive num­bers show less  (see the math­e­mat­i­cal sup­ple­ment here).

As part of the Drake-Kar­da­shev-Fer­mi con­cepts, the Kar­da­shev scale sets the speed lim­its in the Fer­mi para­dox. It mea­sures the civilization’s abil­i­ty to change the lim­its in the Drake equa­tion.  We will explore this idea in future posts.