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Cooling To Absolute Zero Mathematically Outlawed After a Century (newscientist.com)
After more than 100 years of debate -- which at one point even elicited interest from Albert Einstein and Max Planck, physicists have finally offered up mathematical proof of the third law of thermodynamics, which states that a temperature of absolute zero cannot be physically achieved because it's impossible for the entropy (or disorder) of a system to hit zero. While scientists have long suspected that there's an intrinsic 'speed limit' on the act of cooling in our Universe that prevents us from ever achieving absolute zero (0 Kelvin, -273.15 C, or -459.67 F), this is the strongest evidence yet that our current laws of physics hold true when it comes to the lowest possible temperature. From a report on NewScientist: Now Jonathan Oppenheim and Lluis Masanes at University College London have mathematically derived the unattainability principle and placed limits on how fast a system can cool, creating a general proof of the third law. "In computer science, people ask this question all the time: how long does it take to perform a computation?" says Oppenheim. "Just as a computing machine performs a computation, a cooling machine cools a system." So, he and Masanes asked how long it takes to get cold. Cooling can be thought of as a series of steps: heat is removed from the system and dumped into the surrounding environment again and again, and each time the system gets colder. How cold depends on how much work can be done to remove the heat and the size of the reservoir for dumping it. By applying mathematical techniques from quantum information theory, they proved that no real system will ever reach 0 kelvin: it would take an infinite number of steps. Getting close to absolute zero is possible, though, and Masanes and Oppenheim quantified the steps of cooling, setting speed limits for how cold a given system can get in finite time.
Nope.. .Still wrong.
As an atom spins it gives off infrared energy. The slower it spins, the less infrared energy it will give off also contracting in size.
Since EVERYTHING in the known universe gives off infrared energy, it is near impossible to shield infrared energy from reaching the atom and it is highly unlikely for it ever to reach absolute zero.
Absolute zero is the point that the atom will no longer spin. They are correct that absolute zero will never be attainable from an object of mass.
BUT...
The problem nobody talks about is that object of mass doesn't need to stay an object of mass. At absolute zero it will return to the energy that it was before it became mass, AND absolute zero is attained because photons do not give off heat.
But then again, it is no longer mass., so who cares?
Nathan
One: I think you mean "ruled out" rather than "outlawed." That implies some sort of change in the legality rather than a revealing of a "legality" (which is a somewhat obtuse way of looking at this since science is a system of attempting to describe reality rather than an attempt to describe some sort of human invention or behavior) that already existed.
Two: This has an interesting implication for our universe, I think. It's possible that the entropy eventually reaches 0 in the universe as a whole (since this apparently applies to localized entropy), but if that's actually impossible, it means there will always be *some* sort of entropy in the universe regardless of its size. I would think this to mean that a universe "death" of expansion is preferable to a universe death of collapse, at least from the perspective of life. With no entropy, there isn't really existence.
I had the same thought, and this is actually the rare case where it might apply!
In real life as far as movement goes you're never actually trying to get to an exact point. For one thing, because of uncertainty in measurements you can't ever get to an _exact_ point. You can't even tell _exactly_ where something is. On top of that (literally in this case) objects take up space, even individual atoms, so if you move an object to a point it won't be exactly at that point, it will be overlapping that point to some degree. So no matter how precise you're trying to be you're always overshooting at least a little bit. Which means that even ignoring the problem of calculus Xeno's paradox has a hole in it. You're never trying to get exactly to a point, you're actually trying to get to a little past the point and just stopping once you're close enough/sufficiently overlapping. It's effectively the same as starting out trying to run twice the distance, getting halfway, and declaring yourself done.
The difference in this case is twofold, one: there's no "past the point" you can aim for. The whole idea of absolute zero is that it's the lowest you can go. Two: they seem to be saying that there is no quanta of temperature. You can never remove the last bit, you can only remove a portion of what is there.
Assuming that the second part is correct (i'll leave the proof or disproof of that to actual scientists =) the first part makes it impossible to ever arrive at actual zero.
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If you cooled it to absolute 0 you would know the velocity is rpecisely 0. That is a violation of Heisenberg's uncertainty principle.
wake up and hold your nose