Talk:Vacuum energy

message: Surely the concept of vacuum energy is nonsense because a vacuum by itself cannot do work. Yes there are effects like Casimir quantum effects etc but those things are only observed when something is in the vacuum, eg two plates coming close together feel an attraction etc due to uncertainty principles etc.  What would be more useful to know is a conversion factor from general relativity. In other words: how much energy is required to compress or stretch space? we know from GR that the sun or massive body will curve space by a certain amount. that would be a lot of energy/mass. But is this always the case? For example what about the Higgs field, that confers mass on objects.  But at quantum scales it seems gravitational forces may be higher due to symmetry breaking. For example the formation of mini black holes as a result of beam collisions.  http://en.wikipedia.org/wiki/Mini_black_holes  — Preceding unsigned comment added by 203.22.239.98 (talk) 03:44, 26 December 2012 (UTC)
thread_title: Energy as a capacity to do work

message: There should be a comparison between vacuum energy and dark energy.  — Preceding unsigned comment added by Mastertek (talk • contribs) 09:15, 21 September 2011 (UTC)
thread_title: Vacuum energy vs. Dark energy

message: It seems that much of this article is in fact about Zero-point energy and duplicates the content of that article. I have proposed a merge. Sections about Zero-point energy should be removed and the material merged into Zero-point energy. (I do not know if we will have much more left than a disambiguation page.)
Petri Krohn 02:44, 30 March 2006 (UTC)
replies: text: See Talk:Zero-point energy for a possible undisclosed conflict of interest in edits by  as the pltn13.pacbell.net anon.  These might represent a newbie who didn't realize how this would appear, but the situation bears monitoring. ---CH 08:43, 25 May 2006 (UTC)

text: , aka the Kansas City library anon, has removed without comment the merge proposal.  I have reverted this.  I kept the change from Van der Vaals to Van der Waals. ---CH 00:45, 21 June 2006 (UTC)
replies: text: My post on The ZPE talk page is as follows: "I'm going to assume that this argument is over (as the last message was in April, it's now July) - I'm going to remove the merge tag as the majority of posts disagree with the proposal. Furthermore, it's just plain silly!" ... so be it. Your one true god is David P. A. Hunter, esq. III  Talk to me!  09:41, 1 July 2006 (UTC)
thread_title: Merge to [[Zero-point energy]]

message: As of 6 Jul 2006: The vacuum energy results in existence of most (if not all) fundamental forces - and thus in all effects involving these forces too - and is observed in various experiments (like spontaneous emission of light or gamma radiation, Casimir effect, Van-Der Waals bonds, Lamb shift, etc) and has consequences for the behavior of the Universe on cosmological scales.
This doesn't make any sense (gramatically or scientifically):
* results n existence of  - do you mean "causes" or "is caused by"? I guess the latter.
* most (if not all) - incredibly woolly for a scientific note. If we assume GUT, then the three observed fundamental forces (gravity, electroweak, strong) are just different aspects of the same force. So just say "all".
* observed - we don't observe the vacuum energy directly (or we could make it do work and get a free lunch).
* spontaneous emission of light or gamma radiation - I guess you mean emission of photons from excited atomic states. "Light" to a layman is visible light, so that's a very narrow band of the spectrum. "Gamma" refers to electromagnetic radiation with energy above 10 keV that originates from nuclear processes (ie, not atomic transitions). Just say "spontaneous emission" then you cover everything from microwaves to hard K-shell X-rays.
* etc - Only use "etc." if it should be obvious to the reader how to continue the list, eg. the fruit salad contained apples, pears, grapes, etc. I don't think the average reader can guess the next experiment on this list, so just use "eg" at the front to indicate that these are just a few examples from many.
Lumping all that together, I'd propose the following rewrite:
The vaccuum energy arises from the field associated with all fundamental forces. Its effects can be observed in various phenomena (eg, spontaneous emission, Casimir effect, Van der Waals force, Lamb shift) and has consequences for the behavior of the Universe on cosmological scales.
--Oscar Bravo 06:52, 6 July 2006 (UTC)
thread_title: Introductory paragraph

message: Don't know if this is the place to ask, but... I've heard about a scientist who, according to news reports, produced a "below ground state" state in hydrogen. Anybody know more?  Trekphiler 20:34, 23 November 2006 (UTC)
thread_title: In a state

message: The article suggests that extracting energy from the vacuum energy is principally impossible. This is not true as the following quote reveals:
"There is growing interest concerning the possibility of tapping zero-point energy and many claims exist of over unity devices (gadgets yielding a greater output than the required input for operation) driven by zero-point energy. In spite of the dubious nature of these claims (to date no such device has passed a rigorous, objective test), the concept of converting some amount of zero-point energy to usable energy cannot be ruled out in principle. Zero-point energy is not a thermal reservoir, and therefore does not suffer from the thermodynamic injunction against extracting energy from a lower temperature reservoir. ..."
http://www.calphysics.org/zpe.html  —Preceding unsigned comment added by 195.243.113.250 (talk) 15:59, 14 December 2007 (UTC)
replies: text: Sorry, last "perpetual motion" deletion was mine while unsigned. But at least since Tesla you will hardly find perpetual motion claims from these inventors. They do not claim overcoming the law of conservation of energy, but tapping energy from the vacuum as an external source. Using their devices one would have energy free from paying, like someone having a well at home would save his paying for water. Lacerda (talk) 00:55, 5 January 2008 (UTC)

text: So he claims - but to my knowledge, the Physics world has not been set on fire by his 'findings.' HammerFilmFan (talk) 09:25, 10 May 2012 (UTC)

text: That is an intriguing thought experiment, but dark energy actually would mess it up.  If matter or radiation dominate, the expansion decelerates.  If dark energy dominates, the expansion accelerates.  In either case, the nice equilibrium you want to set up with your two orbiting masses will be ruined.  (Vacuum energy is not the ultimate source of cosmic expansion.)  You only maintain the equilibrium if the expansion is steady, which only can be maintained stably in an empty universe with no vacuum energy nor any other kind of energy (except possibly for spacetime curvature).  In that case, since the total gravitational potential energy of the universe is increasing with the expansion, the energy content of the gravitational radiation would derive from that.50.174.178.168 (talk) 04:27, 3 February 2016 (UTC)
thread_title:  Extracting of Energy Impossible 

message: Hang on a second:
 
The net energy of the universe remains zero so long as the particle pairs annihilate each other within Planck time.
I read somewhere that the Planck time is the quantum of time. Something's wrong. If this is true then how can the particle pairs annihilate each other within the Planck time? Please will someone explain.Quaver92 (talk) 13:14, 14 February 2008 (UTC)
replies: text: That the Planck time is a quantum of time is not an accepted theory yet. In fact right now we still have to establish whether such a quantum exists. But you are right, if that theory were to be correct then processes won't be able to happen within that quantum and that will thus answer age old problems such as quantum decoherence. a 05:02, 15 September 2010 (UTC)
thread_title:  Time Quanta 

message: Open Source Inertia Project: http://www.wiki1.net/groups/pmwiki.php?n=BigCrash.Inertia
If you that gravity around massive objects is a curvature of space accelerating matter toward the massive object, and you accept vacuum energy, then very dense vacuum energy might be expected to generate the same curvature of space accelerating matter toward the dense energy (accelerate elemental particles outward in all directions, felt as resistance to change in motion, see proposed mechanics and math at BigCrash.org > Inertia)  --Jtankers (talk) 12:49, 25 April 2008 (UTC)
thread_title:  Vacuum Gravity and Inertial Forces 

message: The calculation of infinite vacuum energy assumes the mass-energy of virtual particles is the same as that of real particles.  That seems like an unwarranted assumption, real and virtual particles are not identical, and vacuum has little or no mass.  Of course there is the possibility of something cancelling the mass-energy out, which the article mentions.  I would add the alternative of the mass-energy of virtual particles being improperly assumed to this and the zero-point energy article, but I do not yet have a source.  Perhaps my point is already there, buried in the term renormalization. ~Paul V. Keller 17:46, 15 December 2008 (UTC)
thread_title: Mass-energy of vitual particles

message: Is vacuum energy a Causality Loop. It seems like our current Interpretation of it implies that it is. 162.18.76.206 (talk) 21:02, 26 January 2009 (UTC)
thread_title:  Causality Loops 

message: Hi.
I saw this bit:
"The existence of vacuum energy is also sometimes used, outside of mainstream physics, as controversial theoretical justification for the possibility of free energy machines. It has been argued that due to the broken symmetry (in QED), free energy does not violate conservation of energy, since the laws of thermodynamics only apply to equilibrium systems. However, consensus among particle physicists is that this is incorrect and that vacuum energy cannot be harnessed to do usable work. In particular, the second law of thermodynamics is unaffected by the existence of vacuum energy."
However I didn't think "extracting" vacuum energy would break conservation of energy anyway, because the energy is already there and you're just tapping it, whereas breaching conservation of energy would mean literally creating energy out of nothing. If such a tap is not possible it would seem to have to be due to something else preventing the extraction of the energy. 74.45.72.4 (talk) 01:40, 7 August 2009 (UTC)
thread_title:  Conservation of energy and "Free energy machines" 

message: I haven't been taking Field Theory for very long, so someone smarter than me should address this.  However, we have been using canonical quantization, and vacuum graphs for some time, and yet we have never mentioned the uncertainty principle.  In fact one of my professors said that justifying virtual particles on the basis of the uncertainty principle is bad physics (despite the fact that it is tempting due to its simplicity).  
128.252.173.35 (talk) 05:19, 23 November 2009 (UTC)
thread_title:  Not derived from uncertainty relation 

message: The casimir effect actually generates a weak force from the vacuum energy, so it could theoretically be used to "generate" free energy out of vacuum energy, which is contrary to what is now stated in the article. It is only impossible to generate infinte amounts of free energy and build a perpetuum mobile. The description of the whole problem is much better described under Zero-point_energy#Proposed_free_energy_devices. It would however proabbaly not be economicall feasible to use the casimir effect for generating free energy, because the density of vacuum energy useable for the casimir effect is very low, but it is possible. --MrBurns (talk) 20:34, 27 June 2010 (UTC)
thread_title:  Casimir effect 

message: I removed a sentence added by some wag: "; and breakthroughs in physics are not usually achieved by groups of physicists which are in equilibrium, i.e. a "consensus"" Cerowyn (talk) 04:19, 4 July 2010 (UTC)
replies: text: Why did you do THAT?  I thought it was a useful insight that physicists ought to keep in mind.  "four tildes" :^)  —Preceding unsigned comment added by 71.174.181.244 (talk) 09:51, 19 April 2011 (UTC)
thread_title:  Discordant scientists 

message: the energy geometrical engineering of vacuum and vacuum's virtual elements would have the highest impact on a unit and a unit's characters with time (i.e. changes) consideration.--e:Y,?:G 16:14, 6 September 2010 (UTC)
thread_title:  energy geometrical engineering and vacuum energy 

message: Doesn't this relate to theories about the big bang?  —Preceding unsigned comment added by 129.98.192.111 (talk) 18:48, 28 January 2011 (UTC)
thread_title:  Big Bang 

message: To refer to a "Pure Vacuum","Vacuum", "Void" or "Nothing" as Energetic is ridiculous, may I suggest one refers to NEAR-Vacuum, or at least provide information on this point..  — Preceding unsigned comment added by Peter J Schoen (talk • contribs) 06:10, 23 April 2011 (UTC)
replies: text: Not understanding it does not make it "ridiculous". A true vacuum is without excitations, not without fields, else it would be nothing (electromagnetism and gravity would not exist in it).82.248.37.116 (talk) 15:43, 31 August 2012 (UTC)
thread_title:  Vacuum, Void or No'thing.. 

message: "Quantum theory of the vacuum further stipulates that the pressure of the zero-state vacuum energy is always negative and equal to ρ. Thus, the total of ρ-3p becomes -2ρ: A negative value. This calculation implies a repulsive gravitational field, giving rise to expansion, if indeed the vacuum ground state has non-zero energy."
I'm no physicist, but if vacuum energy pressure is always -ρ, then ρ-3p becomes ρ+3ρ = 4ρ. I would like to see this clarified.
63.240.143.147 (talk) 19:53, 27 September 2011 (UTC)
replies: text: Done. I also changed the "expansion" to refer to "acceleration of expansion". George Dishman (talk) 13:04, 16 November 2013 (UTC)
thread_title:  Implications needs clarification 

message: The current lead includes a comparison of 10^-15 joules per cubic centimetre (vacuum energy density from upper limit of the cosmological constant) against 10^113 joules per cubic metre (vacuum energy density from QED).  That's likely to cause confusion.  It'd be nice if the two quantities could be converted into the same units, which would involve multiplying or dividing one of them by a million; but I'm not going to do that myself because I don't know enough of the subject matter to know which units make more sense, or whether it's actually an error and the numbers are really already in the same units but one of them is described incorrectly. 130.179.29.61 (talk) 16:06, 12 December 2011 (UTC)
thread_title:  Unit consistency 

message: In Dark energy, it says that Dark energy makes up 73% of the universe's mass energy, whereas in this article, it says Vacuum energy does and Dark energy is only 23%, can someone either remove or clarify this and add a reference? - 86.42.245.119 (talk) 19:12, 27 October 2012 (UTC)
replies: text: This article should make clear that the links between Vacuum energy, Dark energy and the Accelerating universe are not 100% confirmed, mostly because the math is way off. Hcobb (talk) 20:24, 27 October 2012 (UTC)
replies: text:  "The quantization of a simple harmonic oscillator requires the lowest possible energy, or zero-point energy of such an oscillator to be:
Failed to parse (unknown function\V): {E} =\frac{1}{2}\hbar \V."  — Preceding unsigned comment added by 80.223.102.229 (talk) 19:06, 24 December 2012 (UTC)
thread_title:  Contradiction with 'Dark Energy' article 

message: I am having a hard time seeing how van der Waals bonds is related to vacuum energy. Van der Waals forces are forces between molecules in chemistry, in the order of 0.1 J for a pair of molecules (Intermolecular force). Vacuum energy meanwhile is a concept used in astronomy in the order of < 10^-9 J per m^2 (http://math.ucr.edu/home/baez/vacuum.html) (m^2 is usually millions of molecules), that influences entirely galaxies only by virtue of the enormous volume involved. The order of magnitude, field of application and lack of sources make it seen unlikely that they are related. And if they are as unrelated as I think, no one will probably publish a source saying they are not: it's not even the same group of people working with them. The reason I did not remove it is is that it has been up since May 1st, 2006 and in over 6 years only SmackBot has questioned it by asking a 'citation needed'... Can we remove it until someone finds a citation that supports it? Mverleg (talk) 19:26, 30 December 2012 (UTC)
thread_title:  Van der Waals 

message: The "upper limit of the cosmological constant" is given as 10-9 Joules or 100 ergs per m3. These are not equivalent. The only reference that I found (probably searching with the wrong terms) is 100x10-6 ergs per cm3 (100 ergs per m3) from a blacklisted site: www.preposterousuniverse.com/blog/2011/10/04/dark-energy-faq/. Would someone who is familiar with this please resolve this? (btw not coi) Thank you Jim1138 (talk) 18:54, 6 February 2014 (UTC)
replies: text: I'm getting to this a month later, but I'm now seeing the term as 10-9 Joules or 10-2 ergs, which do appear to be identical values.  I'm going to close this on the assumption that the problem has been correctly resolved, but it would be nice if the source used here was more easily verified.  --j⚛e deckertalk 02:07, 4 March 2014 (UTC)
thread_title:  Edit request 

message: Hi Everyone,
Having studied the subject for some time now, I think the article should be amended for clarity (unfortunately no complete insight):
1: It might be useful to add the mass equivalent of the vacuum energy, which is of the order of 10^96 kg/m³. To put this into perspective, it is about 60 to 70 orders of magnitude higher than a typical stellar black hole. Both values, the energy as well as the mass equivalent, reflect upper limits, derived from the Planck world. So far, there is no physical evidence (observation or experiment) for either value.
2: The vacuum energy is supposed to be effective on the quantum scale, while the dark energy (or cosmological constant) has been derived from observations on cosmic scales. Hence it is questionable to directly relate these energies, bringing forward a "catastrophe" (sometimes just called a cosmic problem) where there is none. I suggest a corresponding disambiguation in the article.
3: As Prof Max Tegmark only recently mentioned (see the World Science U Master Class), it is of vital importance to get some evidence for the constancy of the energy density, predominantly of the dark energy. So far, the dark energy is supposed to have a constant value both per volume and per time, causing the exponential and ongoing expansion of the universe. One proposal has been made, taking gravitational lensing into account. On the other hand, close observation of the galactic voids might be more appropriate; at least, the scales of the largest voids are larger than the proposed scenario and should yield results comparatively easy and sooner.
4: The question on the origin and magnitude of the vacuum energy, however, might remain a problem, which probably will not even be solvable by the LHC, as the detection capability still remains significantly below necessary limits.
Regards
K. Cormann
Germany
80.136.28.181 (talk) 12:23, 1 December 2014 (UTC)
thread_title:  Mass Equivalent and Disambiguation 

message: This is simply to express my appreciation for the discussion of this topic without heavy mathematics. Most of the physics topics in Wikipedia leave me in the dust after the first paragraph. Thanks! JFistere (talk) 20:49, 26 January 2015 (UTC)
thread_title:  Light on Mathematics 

message: The zero-point energy of the vacuum is cancelled out by the vacuum energy penetrating any measurement apparatus attempting to remove the vacuum pressure. This should make the vacuum catastrophe problem moot and questions about the cosmological constant. It has been calculated that the actual matter inside a hydrogen atom is Percent Full = 4 × 10-13 %. See http://education.jlab.org/qa/how-much-of-an-atom-is-empty-space.html. (Len loker (talk) 22:00, 13 May 2016 (UTC)
thread_title:  Vacuum Energy Measurement Problem 

message: This article (especially the lede) has tones that vacuum energy is an actual, domonstrated 'thing'. I understand that physicists may understand that it is not (if it is indeed is not), but to the layman (to who this article should be accessible, I presume) this may be misleading. Many other physics-related articles have this problem as well (especially when it comes to differentiating between scientific theory, math theory and hypothesis). Just thought I should point this out for someeone better versed in this field than I, cheers. THEPROMENADER ✎ ✓ 18:02, 13 January 2017 (UTC)
thread_title:  Hypothesis, 'accepted hypothesis', or demonstrated fact? 

message: As descrived by MAXWELL, Lorentz, Tesla, Poincare,...
2A02:8108:8A80:37D8:153C:CAF6:E4D2:ACA (talk) 20:29, 31 January 2019 (UTC)
thread_title:  ETER 

message: Regarding the introduction: Sabine Hossenfelder argues in https://www.youtube.com/watch?v=bl_wGRfbc3w (from 05:43 to 07:10) that there is no such thing as a "cosmological constant problem", because quantum theory does not make a prediction regarding the cosmological constant. The sentence "... suggest a much larger value of 10^113 joules per cubic meter" would thus just be plain wrong. Professor Tournesol (talk) 10:05, 20 August 2021 (UTC)
thread_title:  Hossenfelder's opinion 

message: There's a result in the news claiming that vacuum energy is bound up in black holes in ancient galaxies, and that this may explain the missing mass in the universe that has also led to postulation of dark matter.  I don't understand this (I hoped this article would help explain) so I'm parking the link here for possible use. 2601:648:8200:990:0:0:0:756C (talk) 04:10, 16 February 2023 (UTC)
thread_title:  Dark energy 

message: Only the fifth reference (Jaffe) has scientific relevance. 2A02:A463:2848:0:DDE9:83E5:6364:D9AB (talk) 23:03, 25 October 2023 (UTC)
replies: text: Could you explain a bit more about what you mean? AntiDionysius (talk) 23:07, 25 October 2023 (UTC)
replies: text: Writing about a scientific topic and then refering to commercial sites is the worst thing you can do from a science perspective. But I know, this is only Wikipedia. It really has nothing to do with science. 2A02:A463:2848:0:DDE9:83E5:6364:D9AB (talk) 12:48, 26 October 2023 (UTC)
replies: text: OK AntiDionysius (talk) 13:10, 26 October 2023 (UTC)
thread_title:  Warning: References of dubious nature