# Planck's units

## Main Question or Discussion Point

How did Max Planck arrive at the constant h = 6.626196 x 10-34 J s? Will we ever reach Planck's temperatures?

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he arrived at it by looking blackbody radiation data. for an excellent discussion about this, you may want to look at the first chapter of the text by Resnick-Eisberg on Quantum Mechanics

James R
Homework Helper
Gold Member
What do you mean by "Planck's temperatures"?

dextercioby
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I think it's $$T_{Planck}=\frac{E_{Planck}}{k_{Boltzmann}}$$...But i'm not sure.

Daniel.

Mk
By Planck Temperture, he means the Planck Heat, about 1042˚K. That's the temperture where space itself boils like water, and bubbles come up - holes in spacetime - wormholes in spacetime. Type III civilizations could be able to get to Planck tempertures, and Type IV civilizations must, in order to fit the requirements

Physicists measure development of a civilization by looking at how much energy they use.

Specifically, we can rank civilizations by their energy consumption, using the following principles:

1) The laws of thermodynamics. Even an advanced civilization is bound by the laws of thermodynamics, especially the Second Law, and can hence be ranked by the energy at their disposal.

2) The laws of stable matter. Baryonic matter (e.g. based on protons and neutrons) tends to clump into three large groupings: planets, stars and galaxies. (This is a well-defined by product of stellar and galactic evolution, thermonuclear fusion, etc.) Thus, their energy will also be based on three distinct types, and this places upper limits on their rate of energy consumption.

3) The laws of planetary evolution. Any advanced civilization must grow in energy consumption faster than the frequency of life-threatening catastrophes (e.g. meteor impacts, ice ages, supernovas, etc.). If they grow any slower, they are doomed to extinction. This places mathematical lower limits on the rate of growth of these civilizations.

In a seminal paper published in 1964 in the Journal of Soviet Astronomy, Russian astrophysicist Nicolai Kardashev theorized that advanced civilizations must therefore be grouped according to three types: Type I, II, and III, which have mastered planetary, stellar and galactic forms of energy, respectively. He calculated that the energy consumption of these three types of civilization would be separated by a factor of many billions. (Kaku, 2004)
Type I Civilization: They have mastered the use of all of a planet's resources, they can control weather, geothermic events, wind and water currents. Possibly in the process have almost exhausted the planet's resources.

Berkeley astronomer Don Goldsmith reminds us that the earth receives about one billionth of the suns energy, and that humans utilize about one millionth of that. So we consume about one million billionth of the suns total energy. At present, our entire planetary energy production is about 10 billion billion ergs per second. (Kaku, 2004)
For example, a Type I civilization is a truly planetary one, which has mastered most forms of planetary energy. Their energy output may be on the order of thousands to millions of times our current planetary output. Mark Twain once said, "Everyone complains about the weather, but no one does anything about it." This may change with a Type I civilization, which has enough energy to modify the weather. They also have enough energy to alter the course of earthquakes, volcanoes, and build cities on their oceans. (Kaku, 2004)
Type II Civilization: They need the full output energy of a star, and may used Freeman Dyson's proposed Dyson sphere, a sphere surounding the star, to more efficiently and capture energies given off by the star. Soon they will colonize star systems, with Van Neumann Probes possibly. Van Neumann Probes theoretical robots that are used to colonize the galaxy, and reproduce by at least the thousands, by landing on asteriods and moons, building probe factories, and harvesting minerals and materials found on them for new ones. The hundreds of thousands of probes all go out and make new ones. This isn't just for fun though. They relay back data to their mother civilization from their trips, so that the mother civilization can find more stars to use.

Type III Civilization: They need energies of entire galaxies, clusters, and superclusters, and rely on Van Neumann Probes, possibly even Van Neumann Nanoprobes to colonize galaxies, and find more and more hospitable enviroments for the mother civilization. They can manipulate black holes as they please, create wormholes where ever they want, and play pinball with stars (not literally), but heck, they can do whatever they want! Hmmm... supernova bombs? That would be the ultamite nuke wouldn't it? They have or used to have black hole computers until they turned obsolete. No known natural catastrophe can kill off a Type III Civilization.

Type IV: This is an almost if not a speculative ranking. According to multiverse theories, there is more than one "universe," in the "universe" - the multiverse. The Type IV Civilization of course uses the energies of entire universes. They by definition can reach the Planck Heat, and travel through time if it is possible.

Physicist Freeman Dyson of the Institute for Advanced Study estimates that, within 200 years or so, we should attain Type I status. In fact, growing at a modest rate of 1% per year, Kardashev estimated that it would take only 3,200 years to reach Type II status, and 5,800 years to reach Type III status.

Currently, our energy output qualifies us for Type 0 status. We derive our energy not from harnessing global forces, but by burning dead plants (e.g. oil and coal). But already, we can see the seeds of a Type I civilization. We see the beginning of a planetary language (English), a planetary communication system (the Internet), a planetary economy (the forging of the European Union), and even the beginnings of a planetary culture (via mass media, TV, rock music, and Hollywood films).

By definition, an advanced civilization must grow faster than the frequency of life-threatening catastrophes. Since large meteor and comet impacts take place once every few thousand years, a Type I civilization must master space travel to deflect space debris within that time frame, which should not be much of a problem. Ice ages may take place on a time scale of tens of thousands of years, so a Type I civilization must learn to modify the weather within that time frame. (Astrobiology Magazine, April 2004)
We are between Type 0.3 and Type 0.8.
Look how far we have come in energy uses once we figured out how to manipulate energy, how to get fossil fuels really going, and how to create electrical power from hydropower, and so forth; we've come up in energy uses in a remarkable amount in just a couple of centuries compared to billions of years our planet has been here ... and this same sort of thing may apply to other civilizations. (Goldsmith)

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Thanks for the cool replies guys. Planck temperature is

$$T_P = \frac{m_P c^2}{k} = \sqrt{\frac{\hbar c^5}{G k^2}} = 1.41679 x 10^{32} K$$

Planck's temperature is basically the big-bang temperature. I don't believe we'll ever reach it (our universe will never run out of energy), maybe only in 100 billion years.

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Kaku is always talking out-of-his-field about the power of computers/robotics/AI/biotech yet he came up with that naive civilization type scheme that completely ignores the acceleartion of the acceleration of our technology toward a "Singularity"-

based on the exponentiation of technology toward nanotechnology/quantum computing/ genetic/biotech engineering/etc the human race will go from sub type-I to typeI III-IV within just a few decades- type I/II/and III civilizations are like absurd star trek/star wars societies where technology and cultural development has stagnated at post-industrial levels- like a secondary dark age-

due to the extreme parallel and plural technologies yielding accelerating returns- if one line of research starts to slow down- a dozen other more scalable approaches will take it's place- eg long before Moore's Law putters out we already have aggresive development of quantum computing/ nanocomputing/ biocomputing [using DNA]/ distributed computing which all dwarf the processing power predicted by Moore's Law and approach the theoretical limits of computation

if humankind doesn't achiev type-IV status before 2050- it will only be because we somehow went extinct- there is simply no time for type I/II/III civilizations to exist- they progress to the next stage almost instantly