Talk:Zero-point energy

From RationalWiki
Jump to navigation Jump to search

'Twas me wot dunnit. Dropped offline or got timed out or whatever! SJGMay the bird of paradise ... 18:21, 13 September 2007 (MDT)

Picky!

Wha?[edit]

This article doesn't seem right to me. ZPE is energy inherent in something that's at absolute zero? Uh, no, Heisenburg's Uncertainty Principle is basically "observation effects change", thus, in order to know the position of a particle, you must bombard it with rays smaller than the particle you're observing, thus imparting overly significant energy, while if you want to find the energy of a particle, you must bombard it with rays that are larger than the particle, and thus it is insufficient to note the position of the particle. Nothing in the idea says anything that there "must be energy in a particle at absolute zero" (note, the energy must be in the particle, the particle itself is energy, because of energy-mass equivalence... better known as e=mc2) The idea is, that at absolute zero, you can't know where the particle is, because in order to find it, you have to hit it with a ray that will cause a force which will induce entropy into the particle (and thus energy, and movement).

What I have understood zero-point energy to be, is the idea that... no wait, that's vacuum energy... That even in a vacuum particle/anti-particle pairs are spontaneously generated all the time, and then annihilated shortly thereafter. It's a lot of the reason why black holes emit radiation. But either way, the idea presented in this article (if it's accurate for the term) implies pseudoscience itself. --Eira omtg! The Goat be praised. 05:44, 20 June 2008 (EDT)

No. Heisenberg is not an observer effect.
The location & velocity of any particle at the same time have an inherent maximum magnitude of precision, as one is known more precisely the other becomes less so - I can't xplain it - suggest you wiki it. (I'm 7 miles from home on my pda walking the canal towpath so not very fast) 82.132.136.198 08:15, 20 June 2008 (EDT) (SusanG)
Which can be explained as an observer effect, just on a quantum scale, as per my explanation. --Eira omtg! The Goat be praised. 14:39, 20 June 2008 (EDT)
PS. I looked up "zero-point energy" on Wikipedia, and it does appear to be synonymous with "vacuum energy"... not clear how... all of those articles are still quite complicated, and have more cosmology material in them, than physics material. --Eira omtg! The Goat be praised. 14:52, 20 June 2008 (EDT)
In quantum physics, the Heisenberg uncertainty principle is the statement that locating a particle in a small region of space makes the momentum of the particle uncertain; and conversely, that measuring the momentum of a particle precisely makes the position uncertain.[1]
(my emphasis added to note that it is an observer effect) --Eira omtg! The Goat be praised. 16:00, 20 June 2008 (EDT)
Not that I understand this stuff at all, but apparently not. --AKjeldsenPotential fundamentalist! 17:33, 20 June 2008 (EDT)
After reading through the whole Heisenburg Uncertainty page, it all comes down to how you interpret Quantum Mechanics. From the Copenhagen interpretation, it is not an observer effect, but a fundamental fact of nature (this interpretation is the standard modern interpretation, basically that Quantum mechanics as described is literally how things are), while if you take an Ensemble interpretation, it _is_ an observer effect, just simply one that is impossible to get rid of due to the nature of physical reality. In fact, Heisenburg himself first propagated his idea with exactly the information that I indicated above (substitute "energy" for "momentum" however.) The issue is, with an observer effect with say, an apple, you can get to a scale where observing its position and momentum are possible without observably interfering with it. Heisenburg's uncertainty principle comes about because the physical limits of the Universe prevent further and deeper examination or accuracy. We would need sub-fundamental particles, and none such exist. To locate a photon, we must use another photon, we cannot use anything else, and at that point we run into Quantum Mechanics, which is a statistical model of the universe, rather than a definitive model of the universe. So, while using two balls on a frictionless pool table, we can verify that each is in a discrete position , and momentum at a specific time, but if we set it up, where you cannot see anything, you're simply allowed to toss one of the balls around, and when the balls contact, you then get a strobe light that flickers on momentarily, one would be just as incapable of determining both position and momentum of such a ball, than one would with two photons. It's that fundamentally, we've discovered the world to such a level that we cannot say with certainty any of the actions of the balls. Now, with the pool table above, one could develop a number of theories about how it works, but all of these would be unverifiable. "The two balls exist as a wavefunction describing how likely that ball is to collapse in a specific spot, until they actually do collapse each other by collision", or "the two balls exist in discrete but impossible to know positions, until they collide". Practically, the issue is that we will simply never know which is right, and neither make different predictions about anything, it's all meta-physical debate as to if the wave-functions are actually real, or simply our only mathematically possible way of describing the actions of two discrete particles. Either way, we run into a "veil of perception"; we do not know the actual nature of our observations, we simply know how to describe how they work. --Eira omtg! The Goat be praised. 18:55, 20 June 2008 (EDT)
The trouble with quantum (Good title for a book that!) is that to those like me, and apparently AKj above, who haven't really studied it but only read the popularisations of it, it is indistinguishable from woo. I have to take the assertions of those who claim to understand and accept it (which apparently wouldn't have included Albert who's name be praised). The whole thing is so counter-intuitive that it all begins to read like Alice in Wonderland after a while. Heisenberg is one of the areas (Schrödinger and entanglement being two of the others) where one (well me anyhow - sorry) has to take the words and logic of others on faith (there I've used the "F" word). I usually find that, while I'm reading about this sort of thing, it all seems perfectly rational and logical but ask me twenty four hours later and I won't be able to reiterate the premise -> conclusion trail with any conviction. Please do with this page as you will. SusanG  ContribsTalk 22:50, 20 June 2008 (EDT)

Quantum physics does feel woo-ish when you start looking at its counter intuitive nature. However, it makes predictions that are falsafislable. Those experiments are verified. So far, every single test that they have come up with shows that quantum physics is an accurate way to describe the universe. A good book, designed for the non-scientist on the quantum realm is Quantum A Guide for the Perplexed by Jim Al-Khalili[2] Another good one is Six Easy Pieces by Richard P. Feynman[3] (you can get the lecture on audio[4]) The thing is, you don't have to take it on faith. You can do experiments (might be beyond the average person to do it, but not the average college undergrad physics lab) that prove quantum physics makes the best predictions. The most 'wooish' one is that of the double slit experiment.[5] where when you fire photons, electrons, or even buckyballs[6] an interference pattern shows up as if they were a wave (thats 60 atom carbon moloclue acting as a wave). This pattern goes away when you try to figure out which path the object took through the two slits. The interpretations are the ones that confuse people and argue about - there are questions of hidden variables, infinite parallel universes, sum over possible histories, backwards time messages, The thing is, these interpretations are people trying to make sense what happens - but they do not change the underlying predictions and that it works. A good number of physicists follow the "shut up and compute" interpretation that has the pragmatic view of "the interpretation doesn't matter as long as the equations match what we see." --Shagie 23:16, 20 June 2008 (EDT)

Popularisations of Quantum[edit]

Over the years (since the 60s!) I must have read two dozen plus quantum & allied books. I always understand them while I'm reading them and for a couple of days afterwards but then the woo creeps into my brain & dissolves my neurons or something. I haven't ever had the physical equipment to test these things and have to take the results of others on faith (spit, wash out mouth with soap) unfortunately. SusanG  ContribsTalk 23:34, 20 June 2008 (EDT)

The simplest setup to see with a cathode ray tube with two slits in it that looks like [7]. This could be made by a glass blower and electrician and tested for yourself. You would see a diffraction pattern, though the importance of that wouldn't mean much unless you understood what you were seeing and why that shouldn't be under classical physics. To an extent even a classic CRT with a single slit will show diffraction though not the interference pattern. Thats 1850's technology. --Shagie 00:45, 21 June 2008 (EDT)
Oh we did all that shit @ school - the trick is to do it one photon at a time & still get a diffraction pattern. SusanG  ContribsTalk 02:24, 21 June 2008 (EDT)
That requires a more advanced setup that is college lab level. I'm still fascinated by the one buckyball at a time shows a diffraction pattern. Though this goes to the question of "what do you accept?" Is a reproducible experiment in a journal acceptable? Geology, chemistry, physics, astronomy, quantum physics, biology... I can't verify gravitational lensing with the telescope ability I have nor do I have 20 years of E. coli sitting in my fridge (some molds, yes... but thats not a controlled environment). Still, the universe is an amazing place and Dr. Joe Liske of the Hubblecast says"once again, nature has surprised us beyond our wildest imagination." At some point you either have to accept that not everything in the universe can be verified in the home or believe in a conspiracy of scientists. --Shagie 02:37, 21 June 2008 (EDT)
That's where the Faith (Turn round three times, spit and say "marmaduke Marmaduke, wherefore art thou Marmaduke". To ward off evil) comes in: you've gotta have faith (...) in the honesty of scientists. SusanG  ContribsTalk 02:45, 21 June 2008 (EDT) (which I have btw) SusanG  ContribsTalk
I'm not sure that is really "Faith", it's a reasonable extrapolation, at the very least from high-tech devices which do amazing things exactly as they are supposed to. Colloquially, one could call it "faith in scientists", but it's not a schlafyesque blind faith. ħumanUser talk:Human 20:44, 23 June 2008 (EDT)
I think you're on the verge of coining a new term, Human—Informed faith. Or rather, you were. Because you never actually got around to saying it, I call dibs : ) Star of David.png Radioactive afikomen Please ignore all my awful pre-2014 comments. 20:53, 23 June 2008 (EDT)

Yeah >_< I've noticed that Quantum Mechanics makes people's brains fry. I get the ideas and I understand the issues, mostly because I'm capable of entering the "shut up and compute" mentality. It's like you have to have the mind-set available to think about everything as if it doesn't apply to the real world, yet knowing that oddly enough, it does apply to the real world.

As for faith in Quantum Mechanics, the mechanisms that allow Transistors to work is based on Quantum Tunneling, as well a number of other computer-related stuff. So, the mere fact that you can read what I'm writing here is pretty damn good evidence (on the scale of oh... billions if not trillions, or quatrillions of tests).

Anyways, I'm reminded of two things, first Weird Al's "Living in the Fridge" (sung to the tune, "Living on the Edge") "If you can identify that thing over there, well Mr, you're a better man than I"... from the fridge mold-experiment convo *eyes wander*.

And the other that I'm reminded of is a mathematician joke: An engineer and a mathematician go to a presentation about 9-dimensional space. During the entire presentation, the engineer slowly grew more and more frustrated trying to wrap his head around the ideas presented, yet looking to his left, the mathematician was following the presentation quite eagerly, and apparently with full understanding. After the presentation was over, the engineer asked the mathematician "Did you understand any of that?" and the mathematician says "Of course I did, didn't you?" and the engineer replied, "Of course not. How can you visualize 9-dimensional space?" to which the mathematician responds, "easy, I imagine an n-dimensional space, and let n=9." :) The humor of the story (sorry, ruining the joke here) is that the mathematician is used to dealing with everything as entirely abstract with no relation to "real world", while the engineer is too concrete with "reality" and how it works, that she has difficulty grasping anything at all having to deal with abstractness. ... ... ... now, I have about eight hojillion more jokes about mathematicians being too abstract, so don't think I'm letting them off the hook. --Eira omtg! The Goat be praised. 05:09, 23 June 2008 (EDT)

"Hojillion"? Are you summoning the spirit of Hoji? Star of David.png Radioactive afikomen Please ignore all my awful pre-2014 comments. 05:16, 23 June 2008 (EDT)
Actually, I don't know who first came up with it, but it's basically from Penny Arcade's Tycho. "Hojillion" on wiktionary. --Eira omtg! The Goat be praised. 14:00, 23 June 2008 (EDT)
Speaking of popularisation: http://en.wikipedia.org/wiki/Gravity_gun :P Nullahnung (talk) 05:50, 27 August 2013 (UTC)