Very
Cool. Anyone have any idea what happens when we take all of the energy out of matter at absolute zero, or if it is possible, generally interested?
Physicists working at the US National Institute of Standards and Technology (NIST) have developed a way to theoretically cool an object to absolute zero. This groundbreaking technique, detailed in Nature today, has been used to chill a vibrating aluminium membrane to 360 microKelvin, a temperature below the “quantum limit.” …
I think the simple version is like this:
Temperature is internal motion and at absolute zero the atoms are motionless. Then you run into a problem with the uncertainty principle which states that there is a limit to the how well you can know the position and speed of a particle. And increased precision in one decreases it in the other. At absolute zero you then know the speed and thus you no longer know where the particle is.
Or something like that.
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antum theory states mass should not exist. One of the possibilities is that the level of energy is so low as to break down the forces holding particles together which would be a very interesting way of examine the building blocks without a particle
Have you heard of chemistry. Mass exists, within that mass exists enough energy to keep that mass together and when we break that energy we get the trouble governments have been worrying about since the 50s.
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Interesting question which leads me to this... If we cool down to the point that all the energy is removed, wouldn't all particles in an atom no longer be held apart? In other words, would the atom collapse upon itself and if enough do that, would or could it form a type of black hole?
" If we cool down to the point that all the energy is removed,"
To reiterate : cooling to ~0K has no connection with removing all energy. Even at 0K chemical bonds will still be present let alone the nuclear forces .etc. Electrons will still be in their orbitals This a non-question !
In other words, they appear to be calling displacements of the membrane perpendicular to its expanse 'heat', and damping of those excursions 'cooling'. No doubt the membrane's constituent atoms' heat kinetic energy has been reduced to extremely low cryogenic T, but that's not the focus of the article, nor is it anything exceptional.
"Cool. Anyone have any idea what happens when we take all of the energy out of matter at absolute zero, or if it is possible, generally interested?"
You know those ball and stick molecular models? Imagine the sticks all suddenly disappearing :-)
Maybe al the "balls" will drop into a single, ultra dense clump and disappear down it's own micro black hole.
I can't remember how many times I read a throwaway remark to perfect food storage techniques in all the sci-fi books I have read. It seems obvious that, if you stop all molecular activity in an object (ie a steak), that object will no longer deteriorate since deteriorating costs energy which the object no longer has.
This theoretical tech would mean supracooling an object down to a handful of Kelvin, then squeezing the rest of the energy out via microwaves. Neat trick, and nice way to think out of the box. Kudos to the boffins having boffinated that one. Now we finally have a possible explanation for that sci-fi tech that seemed so cool at the time.
When it comes to preserving a steak I doubt it matters much if you go to .1K or .00001K. At that point it just doesn't make a noticable difference. (I also doubt you can cool a steak to those temperatures without freezer burn and ending up with an inedible glob after thawing)
Surely any food out here in the real-world already contains the agents of its own decomposition - isn't more a game of trying to prevent them to act? Wouldn't any means of perfectly destroying organic agents in the food also destroy some or all of the organic nature of the food itself...? I admit I'm clueless on this...
I also doubt you can cool a steak to those temperatures without freezer burn
Counterpoint: Freezer burn is dependent on dehydration by sublimation of water from the food, and oxygenation of fats. Chilling a slab of meat below 1K would have the effect of virtually halting sublimation and oxygenation, both of which are temperature-driven processes.
I could probably rig a test in a lab with liquid nitrogen (merely 77K) to figure out which of us is correct, but the likely timeline means I'd have to leave open a nitrogen tap for weeks to maintain the steak's temperature. The lab guys are all about playing mad scientist on lunch break to verify things they saw on YouTube but a weeks-long unattended experiment might strain their tolerance.
Assuming that the steak could be set at this temperature, from a practical point, would it be worth the energy to keep it there and then the energy to get it to a point where it could be consumed?
It might be less energy to just keep a cow around until one needs it.
Assuming that the steak could be set at this temperature, from a practical point, would it be worth the energy to keep it there and then the energy to get it to a point where it could be consumed?
Short version: no, warming a steak from liquid helium temperatures doesn't require much energy compared to, say, boiling a liter of water.
Long version:
Treating meat as water because I'm too lazy to look up heat capacities of a mixed fat-protein-water material, then to heat a 500-gram steak from 0.0000001K to 273K would require:
273K x 500g x 2.108 J/g*K = 287,742 Joules
Meanwhile, thawing a 500-gram block of ice...er, simplified meat model for physics purposes...requires:
500g x 333.55J/g = 166,775 Joules
Then heating the defrosted steak to a good "medium" condition (140F / 333K interior) from 273K requires:
60K x 500g x 4.184J/g*K = 125,520 Joules
Meanwhile, boiling a liter of 20C water to make tea requires:
80K x 1000g x 4.184J/g*K + 1000g x 2257J/g = 2,591,720J
NOTES
1) Organic substances like proteins, oils, fats, etc. tend to have about half the heat capacity of water, so the values presented above for the steak approximation are high. Commentators with a stronger work ethic could probably Google better values.
2) I ignored the temperature dependence of ice's heat capacity, which varies between 0K and 273K. Energy values are further overstated as heat capacities of solids tend to drop with decreasing temperature.
3) Grilling over charcoal or gas will see a significant amount of energy wasted into the surroundings rather than entering the steak, which generally only occupies a fraction of the grilling area. Even closing the lid on a nice backyard grill is not going to put more than a percentage of heat into a single steak. Comparatively, thawing a steak from liquid helium temperatures is a minor increase in energy requirements.
4) Obviously, some additional energy for thawing the steak could be taken from the ketchup that, in a properly cooked steak, should be drenched all over its surface. (I keed, I keed.)
CONCLUSION
Boiling water for tea or coffee is likely to consume more energy than cooking a steak pulled from a cryogenic freezer.
I could probably rig a test in a lab with liquid nitrogen...
The simple way to avoid freezer burn on your steak is to put a glaze of water on it and then vacuum seal it in a plastic pack - its temperature is not going to matter much as long as it is frozen. On the other hand, irradiating it and leaving it in a sealed plastic bag in your pantry would work, too, though it would require a different set of equipment. Why don't you try both and tell the class how it turned out?
First, temperature is essentially a measure of kinetic energy (it's actually a bit more complicated than that, but it's close enough to think of it as the average kinetic energy of particles). If you cool something to absolute zero, that means you have reduced its kinetic energy to zero, not its total energy. E = mc2 is not actually correct. The full equations is E = p2c2 + m2c4, where p is momentum. If you reduce kinetic energy to zero, that is the same as reducing p to zero, which obviously still leaves you with the E = mc2 part - it's called rest mass precisely because it is the energy of a particle at rest, ie. zero kinetic energy, ie. at absolute zero. Claiming that mass disappears is you cool a particle down is pretty much the exact opposite of what the equation says.
As for things "chemically falling apart" when they get cold, that makes even less sense. Chemistry is about reactions involving the electrons bound to atoms and molecules. It has nothing whatsoever to do with nuclear or subatomic physics. Quarks and gluons do not undergo chemical reactions. If you cool certain things (bosons, oddly enough) down enough they can form a Bose-Einstein condensate, but that is not a chemical reaction and it certainly doesn't mean they've fallen apart - again, condensation is pretty much exact opposite of that.
Thirdly, things falling apart specifically because they're too cold to emit gluons, is again utter nonsense. Forces are transmitted by the exchange of virtual particles. It's complicated to explains without going in to the maths, but essentially the energy for them is always borrowed and has nothing whatsoever to do with the energy of the particles involved; an electron at absolute zero is still a charged particle with an electric field, it doesn't suddenly become neutral or cease to exist just because you've cooled it down. This is ultimately down to the uncertainty principle - this doesn't just cover position/momentum, but also other pairs of properties one of the most important of which is energy/time. Essentially, a virtual particle can appear out of nowhere and as long as it doesn't last for too long the universe won't notice the imbalance in energy. This is also the mechanism behind things like the Casimir effect and Hawking radiation from black holes.
Finally, we understand spin very well, spin energy is not some bizarre mystery, and photons are not regarded as "pure discrete units of energy" they are simply particles like any other with their own set of well understood properties, and quantum theory does not say mass should not exist (the whole point of any theory is to explain observations, so it would be a bit of a shit theory if that were the case).
As for the article itself, it looks like a neat experiment. However, there's nothing "below the quantum limit" about it. Using a new technique, they can cool things below the limits of a different technique. And no, it won't be the key to reaching absolute zero because that's not possible. As the article itself quotes - " If the light could be perfectly “squeezed” then it would be possible to cool the vibrational motions “arbitrarily close” to absolute zero". Not "we could use this to get to absolute zero" but "if we could make everything perfect we could get really close to absolute zero". I'm sure I've said it before, but it's really sad that the media constantly needs to make up shit about things breaking predictions (hint: if this wasn't predicted by quantum mechanics, what exactly do you think they used to design the experiment?) or leading to things that no-one involved has ever claimed. It's a cool experiment, why not just report what actually happened as stated by the people who actually understand it and gave out quotes explaining it and everything?
So some scientists have found they can use yet another form of energy to remove energy from an object, just like the local unemployable yoof-of-today has learnt to cancel out the background noise of the hood by wearing noise cancelling headphones.
So many parallels, what will they think of next?