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It distresses me to see you basically attach a self-destruct bomb to your philosophy, and program it to go off if the laws of physics take a certain, very likely form. This is not necessary -- the nature and needs of humans aren't going to suddenly shift, depending on the form of the most successful theory of physics. All that changes is your understanding, which means, at most, that you have to generalize your definitions. This is analogous to a bridge builder who decides to burn all his bridge designs after learning about quantum mechanics, because all his bridge designs were based on the "non-existent" classical laws of physics.

The topic was re-opened a long time ago -- a couple years ago iirc. IMO, the real issue is that most of us have a philosophy where "individual decisions" are the big player, and so it bothers some of us that the universe seems to enshrine deterministic evolution as a primary component, regardless of the philosophy we support. I am perpetually on the edge of putting together something to describe why this isn't a problem for individualist philosophy (individual decisions still happen, etc.), but for the fact that no one wants to hear it.

Even if you're not a gun owner, you can click on the "mega pack" (their full collection of printable guns/components) in the following link and have the next best thing as your permanent property -- the ability to print a gun whenever you like. There are already two "reinforced" versions of the AR lower in the list (the "lower" is the part that is legally considered "the gun" -- you can have the upper and all parts necessary to complete it, and it's not considered a gun until you put it on a lower). Presumably they last longer than the first prototype that made news a month or so ago. http://defcad.org/browse/

Cool stuff. Do you know which type of atomic energy states? Electrical, rotational, translational, spin, all of the above? Just curious. -Dylan I don't know what system was used in this particular experiment, but the simplest example of a system like this would be a fixed lattice of spins in the presence of a magnetic field. Each atom then has just two possible states -- one "high energy" state and one "low energy" state. So for a low energy of the whole system, the temperature would be positive, but at a high enough energy of the whole system, the temperature would become negative.

Ugh, it's pretty clear where this is going. I have to admit that the Book of the Revelation of Saint John the Divine was remarkably precient on this subject.

Exactly right. In thermodynamics, the defining relationship for temperature 1/T = dS / dE, where T is temperature, S is entropy, and E is energy (and dS / dE means "the change in entropy as you add energy"). Now the entropy is, roughly speaking, "the number of possible states" of all the constituent atoms. So, positive temperature means that if you add energy to the system, there are more things each particle could randomly do (more states become available). This makes sense for systems with low total energy -- the atoms spend most of their time sitting around at low energy, and only occasionally get bumped around into higher energy states, so adding energy means "more possibilities" for each atom. However, in a system where the number of high-energy states for each atom is limited, you can end up with the opposite situation -- if you add a lot of energy to the entire system, nearly all the atoms have to spend all their time in their own high-energy state, and only occasionally fall back down to their low-energy state. Adding even more energy to the system makes the situation even more restricted -- i.e. there are fewer possible "low energy" states available for each atom. So in this case dS / dE becomes negative -- more energy = fewer possible states. And so that means negative temperature.

Very strong argument, as usual, and expertly delivered. Definitely a long-term reference piece. Another very recent article I liked: http://lewrockwell.com/peters-e/peters-e279.html

Impressive video -- a more accurate title might have been "~95% of psychiatry is a pernicious pseudoscience." I admit this probably wouldn't generate as many hits.