Talk:Fundamental interaction

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ANTIMATTER and MATTER have ± mass?[edit]

Just like to point out that gravity can be deemed to be inversely proportional with regards antimatter as the mass is opposite, i comment on this but it was removed by Dachannien do you think it should be in? RMW42 19:05, 8 March 2007 (UTC)

As I posted to my talk page: The mass of a particle and its antiparticle are identical. See Antiparticle for more info. Also, while it hasn't been experimentally proven, most physicists favor the hypothesis that antimatter attracts antimatter and matter with the same force that matter does. See Gravitational interaction of antimatter for more info. --DachannienTalkContrib 21:31, 8 March 2007 (UTC)

I believe mass is an illusion. Orphadeus (talk) 12:41, 10 May 2011 (UTC)

interaction v. "force"[edit]

Which is the most correct term - '... interaction' or '... nuclear force'. 'Interaction' kind of implies a particle physics way of thinking. Just this needs to be agreed as someone has written a weak nuclear force article which covers the same as the weak interaction stuff. -- Na

Good point - I have a somewhat limited grasp of the nuclear weak force/weak interaction, but I felt that a bit of a stub might interest others in adding to it. (and if not, I've been doing a bit of reading on the subject, and figured I'd fix it up once I had my facts in order) The reason I ended up on weak nuclear force were twofold: 1 - that is the way I had always heard of it and 2 - the page that inspired me to create the entry was theory of everything and the author(s) used strong nuclear force and weak nuclear force so I carried through. Come to think of it, I only stumbled on Theory of Everything - I had always thought it would be grand unification theory. -- DS

"electroweak force"?[edit]

Add to Fundamental force a comment on "electroweak force"?

finite "velocity of gravity"[edit]

I had to modify the description of gravity to include the finite velocity of propagation of gravity. As the article stood, if the universe were infinite, we would have been saying that gravity propagates instantly. AstroNomer 18:41 Aug 20, 2002 (PDT)#

singular or plural?[edit]

Should this be merged with fundamental forces? --Ellmist Saturday, August 31st, 2002

I say yes -- with the plural redirecting here. --mav
Yup. AxelBoldt 07:49 Aug 31, 2002 (PDT)

Table data[edit]

Where do the numbers in the table at the top come from? They're in disagreement with the numbers on the famous poster on fundamental forces and interactions, online care of LBNL (Lawrence Berkeley National Lab) at [1]. When I google for "fundamental force relative strength," every website I hit says something different--probably because it depends upon what actual particles and distances we're putting in to the various equations! We should say something about where these numbers come from. --zandperl 14:59, 28 Sep 2004 (UTC)

the table seems badly aligned, it is overlapped. Can somebody fix this please? (The first table) -- Alvo 07:59, 29 September 2005 (UTC)

Is the Range of the SNF larger than the range of the WNF? If it true I appologize for questioning it, but it seems counterintuitive to me. If anyone can get the values from a respectable source, filling the table and mentioning the source, it would be of help. Seems those values change quite a bit depending on the source. --Nuno Cordeiro 07:13, 28 October 2005 (GMT)

Strong force infinite range and behaviour set to 1 ? Is this right ??
Yes. Whereas the nuclear force has short range, the strong force is 1/r^2 at close range and 1 out to infinity. -- Xerxes 14:21, 28 April 2006 (UTC)

I have cleaned this table up and generally brought it in line with how these tables are usually presented. In the table, the strong force has a short range. In the strong force section, this is clarified and expanded upon. Strait 20:00, 15 June 2006 (UTC)

I suppose it depends crucially on what you mean by range, which is not well defined here. Personally, I feel the current listing is factually incorrect and do not see any way to improve it. My solution: complete elimination of that column. -- Xerxes 23:07, 15 June 2006 (UTC)
Seems like a fine solution. However, I'm still uncomfortable with the strong force having "1" listed as its "long distance behaviour". I'm going to try to clarify this somehow. Strait 16:35, 16 June 2006 (UTC)
Well, if you have the technical sophistication to understand why that's not exactly right, you must also realize that the electromagnetic force is not exactly 1/r2 itself. We can make these approximate relations arbitrarily complicated if we really want to. I think it's more clear to novices if we ignore screening effects such as the running of the coupling or string breaking. -- Xerxes 17:17, 16 June 2006 (UTC)

Issues with Gravity[edit]

It says that the force field theory of gravity (Newtonian) is incorrect. Quantum Mechanics still says that there are different ways of looking at the same thing. Even GR says that gravity is also identical to acceleration. And couldn't the curvature of space be a force field??? If I don't get disproval within a week, I'm going to put that in the article. Sabejias 03:06, 2 Feb 2005 (UTC)

Certainly you can mathematically model gravity as a "force", but it's being distinguished semantically from "real" forces, which are theorized to exert acceleration by particle exchange. -- Beland 05:36, 14 August 2005 (UTC)
This is absurd; gravity is theorized to exert acceleration by graviton exchange. Why is spacetime curvature inconsistent with a gauge field? Eebster the Great (talk) 05:56, 29 January 2009 (UTC)
I've never understood this myself. If gravity is (classically) of the form 1/r^2, why can't QFT describe it satisfactorily like it can explain EM. I recall something about renormalization problems, but I'm no expert on the topic. Whoever will solve this will probably end up with a Nobel prize. Headbomb {ταλκκοντριβςWP Physics} 06:07, 29 January 2009 (UTC)

when did all of this happen ?[edit]

when did all of the fundamental forces become aware of? as of along a timeline? would someone please tell me?

i am not a physics student but would gladly listen.

Gravity[edit]

I removed the section that said:

"But oddly, during a moonwalk where the experiment was repeated, a feather was dropped simultaneously with a moon rock. The moon rock fell slightly faster than the feather. So, there may be more physics experiments to perform in this area."

There is no doubt that the objects would arrive at the same time. I didn't find anything with a feather and a moon rock but this page features a video of the experience done by Astronaut David Scott during Apollo 15 with a feather and a hammer: http://vesuvius.jsc.nasa.gov/er/seh/feather.html.

I am not sure that it is appropriate to write here to document a change. Is there a defined way to document changes when editing? I didn't find that information in the help. Wilhem 84.5.248.255 00:10, 21 December 2005 (UTC)

"There is no doubt that the objects would arrive at the same time." --I was just reading on Wikipedia today that the moon has some charged dust particles floating over its surface, having been charged by solar radiation, that form a haze that obscures visual inspection. If the two dropped objects were to encounter some of these particles, the feather, having more surface area, might encounter more resistance from friction as it fell. Verberate (talk) 03:08, 1 April 2011 (UTC) — Preceding unsigned comment added by Verberate (talkcontribs) 03:06, 1 April 2011 (UTC)

Why is it necessary for gravity to be a fundamental force?[edit]

GR describes gravitation as a curvature of spacetime, and states that there is no force acting on an object under the influence of gravitation.

Given this, why is it assumed that gravity is a fundamental force? Is there an underlying assumption that spacetime couldn’t “curve” without a force acting on it? Is spacetime without the effects of gravitation assumed to be “at rest,” and under some kind of tension where under the influence of a mass?

Is it possible to accept the curvature of spacetime as a property of spacetime itself rather than the result of the action of a force? Would this invalidate anything about quantum mechanics?

Dgroberts@ 03:18, 2 April 2006 (UTC)

Particles source gravity, but a particle in a quantum theory can be in a superposition of distinct positions. This means that the curvature itself can be a superposition of distinct curvatures, which would not be possible in classical physics. Conversely, if you force the curvature to be classical then there's a hidden variable giving away information about true positions of the particles, but such hidden variables contradict the postulates of quantum mechanics. JarahE 01:12, 18 April 2006 (UTC)

JarahE, your comments betray a deeper knowlege of physics than mine. I think you are saying that gravity was "promoted" from a property to a force because as a property it contradicts classical physics on one hand and quantum mechanics on the other. I'm not sure how making gravity a force corrects the contradictions, but I have a feeling that you do! Thanks.

I'm just a high schooler but this is what I think. Gravity is just a distortion in the spacetime continuum and its "strength" is ditermined by the object's mass. It cannot be a form of force because if it were there would be a material which can weaken the force by interrupting the two objects in some way. e.g. Electromagnetic force: by putting an object (a table) in between two magnets the force between the two magnets are weakened. Unless there is a material that can weaken gravity by being put in between two objects experiencing a gravitational pull; gravity cannot be defined as a form of force. If anyone disagrees with a good reason please state your reasons here. I would appreciate new opinions and ideas. —Preceding unsigned comment added by 222.153.21.181 (talk) 10:13, 3 July 2008 (UTC)

Where to begin? First of all, the table will not notably dampen the magnetic force; try a number of different media and see if they all behave the same (all nonmagnetic, uncharged materials will). However, a similar example could be given of an electrical insulator between two wires as compared to a vacuum. I will address that below:
The confusion here stems from the fact that, while the table may seem electromagnetically neutral, it actually consists of many charged particles that cancel on macroscopic scales. These many charges are responsible for disrupting the electrical field between the charges.
Furthermore, I can weaken the gravitational force very easily; consider putting the "damping" material behind the test object. Voila! Again, it is merely the addition of another force that has a canceling effect, not a true "damping."
Also consider that Newton's first law, while perhaps not fully correct according to Quantum Physics, explicitly forbids your interpretation of gravity, since objects do not accelerate in the absence of an unbalanced force. Furthermore, as JarahE pointed out, treating these warps classically contradicts the Heisenberg Uncertainty Principle, while treating them probabilistically resolves this, but also demands that the warps be created by some mediating force particle (the graviton). Thus from both classical and quantum mechanical perspectives, gravity must be a force.
Now, it is true that General Relativity revolutionized the understanding of gravity, and that gravity is indeed well described by warps in spacetime. However, this does not imply that these warps are not caused by a force (gravity). Even Einstein described gravity as one of the fundamental forces (I believe only two were known at the time). General Relativity also does not violate Newton's first law, since whether seen from the perspective of an object in freefall or an inertial reference frame, the object is either at rest in the absence of force, or accelerating due to an unbalanced (gravitational) force, respectively. Eebster the Great (talk) 05:54, 29 January 2009 (UTC)

Errors?[edit]

Maybe it's just me. But I'm getting these errors, in big red font, for the Long-Distance Behaviour:

  • Strong: Failed to parse (Can't write to or create math output directory): 1
  • Electromagnetic: Failed to parse (Can't write to or create math output directory): \frac{1}{r^2}
  • Weak: Failed to parse (Can't write to or create math output directory): \frac{e^{-m_{W,Z}r}}{r}
  • Gravity: Failed to parse (Can't write to or create math output directory): \frac{1}{r^2}

Ideas? 60.224.253.187 12:43, 30 August 2006 (UTC)

It sounds like a personal problem if your computer can't parse "1". —Preceding unsigned comment added by Eebster the Great (talkcontribs) 05:38, 29 January 2009 (UTC)

Stuff[edit]

What is the force where two solid objects collide with each other and apply force to each other, is it "strong force" can we clarify in the artcile?

I diagree that gravery has infinite range whereas other forces like magnatism don't. Both gravery and magnatism have infinite range, and with both the force exerted gets less over distance away from the object. Gravery seems to have more promenace because planets are verry heavy, However even a cheap small frige magnet can pick up a paperclip againsed the force of the graverty of the whole world (earth). Alan2here 15:11, 1 October 2006 (UTC)

The force is contact force. The others aren't words. -lysdexia 21:24, 25 September 2006 (UTC)
The others aren't words? Alan2here 15:11, 1 October 2006 (UTC)
"The others aren't words?" --lol. I think they may be words, though different, but the concepts referenced are the same. Maybe check your spelling for our literally myopic readers, especially 'graverty'.--70.231.72.229 (talk) 08:37, 7 January 2008 (UTC)

If I'm not mistaken, the strong force's only major contribution to the every-day macroscopic world is holding atomic nuclei together, the weak force really doesn't do much under ordinary conditions, gravity does pretty much the things which it's known for, and electromagnetic is responsible for pretty much everything else. I'm not quite sure it's right to say that the "contact force" is purely electromagnetic, because objects are made up of atoms and atoms contain atomic nuclei and without the strong force to hold those nuclei together, even when a force is applied to object, the object wouldn't even be able to exist. What I'm trying to say is that i don't want to rule out the possibility that when the electromagnetic force is applied to the object during contact it puts strain on the nuclei, because if it did, then the strong force would be responsible for counteracting that strain and would thus be a force that if not contributing directly to the contact force at least allows it to exist for any non-nanoscopic period of time. —Preceding unsigned comment added by 209.173.76.152 (talk) 01:31, August 27, 2007 (UTC)

Nonetheless, it is certainly reasonable to state that the electromagnetic force is fundamentally responsible for all contact forces. In fact, virtually every force encountered on a daily basis with the notable exception of gravity but in addition to light and, to a great extent, heat is caused by the electromagnetic force. For this reason, the short-ranged nuclear forces (strong and weak) were discovered far after the long-ranged forces (gravity and electromagnetism). Not until the discovery of the nucleus were smaller attractive forces given much thought. To this day I have no clue where the weak force came from; it just sort of popped up and broke a lot of symmetries. Eebster the Great (talk) 05:37, 29 January 2009 (UTC)
Heh. According to Richard Rhodes, the theory of the weak force was the primary theoretical addition to nuclear physics made by Enrico Fermi; work done before he left Rome for the US. Everything else he did was "just" engineering. SkoreKeep (talk) 19:14, 18 February 2013 (UTC)

About "Long-Distance Behavior"[edit]

Is the range of each interaction circumstantial to the standard ènèrjies that each happen at? That is, the range of E could also be 1, like C (coloral), if its reactions have Schwinger breakdowns that repeat the near-field potentials. Then, C can also have a range that decays greater than 1 if its glueballs are inductively-damped into other gluònic matter? -lysdexia 21:33, 25 September 2006 (UTC)

Date[edit]

"Grand unified theories seek to unify the electroweak force and the strong nuclear interaction, but none have passed experimental muster as of 2006." should the year be changed to 2007? 74.166.189.233 00:26, 14 March 2007 (UTC)

i thought the standard model unifies them. —Preceding unsigned comment added by 209.173.76.152 (talk) 01:42, August 27, 2007 (UTC)

dependence of strong interaction on distance[edit]

I found the following apparently conflicting statements in the section about the strong interaction:

  • This causes the strong interaction's strength to be independent of distance.
  • This nuclear force does not have constant strength for different particle separations, but rather goes as 1/r7 with an effective range of 1.4 x 10−15 m.

Is there a difference in definition between "strong interaction" and "nuclear force" that I'm not aware of?

GilHamiltonTheArm 06:07, 30 March 2007 (UTC)

I think i've heard the weak force refered to as the "nuclear force" before. on the other hand, I'm pretty sure the weak force doesn't have a range as large as 10-15m. I've also heard that the strong force gets stronger with distance (so long as it stays within range).

The strong, nuclear, and weak forces are all different. If I recall correctly, the nuclear force is caused by leakage of the strong force from the quarks confined in the nucleons, and hence while the strong force has infinite range due to confinement (this also prevents us from seeing it at long distances), the nuclear force is effectively a 1/r^7 force. The weak force is for the most part unrelated. I'll try to update the main page with a nice explanation later...I put a better one up years ago but it seems to have been removed, but I'll see what I can dig up after letting people think about things for a bit. Scott.medling (talk) 23:53, 22 January 2008 (UTC)

Rewrite as of 27 April 2007[edit]

The article just went through a rather large rewrite, but the references list didn't change. Were those same sources used in the rewrite of this article? --DachannienTalkContrib 05:39, 28 April 2007 (UTC)

Since the references weren't referenced to the text, I couldn't tell what information was for what. I will add in applicable references later and let someone else decide whether those references are applicable for an article on fundamental interactions. jay 07:27, 29 April 2007 (UTC)

Acceleration In the Absence of Forces[edit]

User:Jgwacker removed my statement about the acceleration of the expansion of the universe with the statement that this didn't require a new force although apparently someone else restored with different wording. I am reminded of a study of scientific knowledge in undergrads at U.S. universities titled "Curvilinear Motion in the Absence of Forces". But perhaps there is an explanation in terms of known forces? Lycurgus 22:47, 25 May 2007 (UTC)

Electromagnetism[edit]

I'm no scientist. I trust that someone smarter than me will consider my fixes under the heading Electromagnetism, and correct any errors I may have introduced. -- TheEditrix2 12:56, 20 June 2007 (UTC)


Special Relativity did not show that the speed of light in a vacuum was a constant. It arose out of Einstein's work to reconcile the Principle of Relativity with research in Electromagnetism that showed the speed of light in a vacuum as a constant. (from Chapter 7, Relativity: The Special and General Theory. Albert Einstein)

An Inconsistency with the Range of Electromagnetism[edit]

The table shows electromagnetism as having a range of 10^45 yet the section for electromagnetism below that states that it is an infinite ranged force (which is what I thought it was anyway). Is it some form of sneaky vandalism? —Preceding unsigned comment added by 67.60.95.67 (talk) 10:19, 9 October 2007 (UTC)


It is described as infinite in both the Gravitation and Electromagnetism sections, but not the table. I don't know the correct answer, but it is inconsistent in the article. --DavePeixotto 01:44, 26 October 2007 (UTC)

In Fiction... Inappropriate?[edit]

Does anyone agree that this is inappropriately placed here? Should I give a rat's patoot about Fundamental Interaction in Piers Anthony's fictional universe - or the role of magic as the fifth force? Give me a break. —Preceding unsigned comment added by 65.28.15.115 (talk) 13:26, 11 December 2007 (UTC)

Acknowledgement of other possible fundamental forces?[edit]

In addition to the proposed 5th force (Q), can it be admitted that there may exist several other forces not currently studied or identified? (I just don't want to mislead others that there are, conclusively, only four 'fundamental' 'forces').--70.231.72.229 (talk) 08:55, 7 January 2008 (UTC)

Gravity - not a big factor of _expansion_ of the universe[edit]

I claim that gravity didn't have much to do with the expansion of the universe, but has a lot to say for the contraption, (e.g. Big Crunch, Omega <=> 1) of the universe! I therefore argue that "the expansion of the universe", from article quote below, should be removed from the article.

Because of its long range, gravity is responsible for such large-scale phenomena as the structure of galaxies, black holes and the expansion of the universe

I agree on the above. Another way of putting it is maybee:

Because of its long range, gravity is responsible for such large-scale phenomena as the structure of galaxies, black holes and "balancing" the dark energy in the expansion of the universe

New image[edit]

This article needs an appropriate lead image of its own and we're working on it at the Graphics Lab. In the meantime this table of Fermions helps with understanding of the interactions. Please comment of the new table of elementary particles at Wikipedia:Graphic_Lab/Images_to_improve#String Theory. Thanks. Dhatfield (talk) 23:01, 28 June 2008 (UTC)

Long-Distance Behavior[edit]

Do you have any sources for the Behaviour of the strong & weak interactions? -- MichaelSchoenitzer (talk) 13:53, 24 November 2008 (UTC)

Dubious[edit]

The table is dubious and confusing. Electroweak theory unifies that unifies eletromagnetic force and weak force. How comes only quantum electrodynamics is the theiry behind electromagnetism and electroweak theory is specific to weak force?Fangfufu (talk) 22:44, 16 December 2008 (UTC)

I agree. Another point in which the article is consistently incosistent is the way it declares that electroweak theory unifies electromagnetism and weak interaction but calls for some GUT in order to unify them with the strong interaction. I know this is a commonly held belief (Even among some high energy physicists), but it's wrong. The Standard model is as much of a unification of three interactions as the electroweak theory is of two. Dauto (talk) 05:30, 2 February 2009 (UTC)
I mildly disagree with the original comment. It is true that QED is contained within Electroweak theory, but there are times when you can neglect all of the other forces except for the electromagnetic (EM) force and QED is perfectly good on its own without worrying about Electroweak theory. In fact, many of the most accurate tests of relativistic quantum field theory were tests of just QED. However, one seldom has opportunity to consider the weak force without the electromagnetic force. So, I think most physicists would agree that QED is a model of the electromagnetic force and Electroweak theory is a model of the weak force. It just happens to model the weak force by unifying it with the EM force at sufficiently high energies. As for the comment about the Standard Model (SM) being as much a unification of the strong and electroweak forces as electroweak theory is a unification of the EM and weak forces, I strongly disagree. The SM simply tacks an SU(3) gauge group onto the SU(2)xU(1) gauge group of the electroweak theory. There is no unification there. The subtly, and where I suspect Dauto is confused, is that it appears to the casual observer that electroweak theory simply tacks an SU(2) gauge group onto the U(1) of QED, but that is NOT the case. The U(1) in the SU(2)xU(1) product gauge group of electroweak theory is NOT the same U(1) as the EM gauge group. After spontaneous symmetry breaking, the U(1) symmetry group that remains unbroken [and which does correspond to the EM U(1)] is not the obvious U(1) subgroup of the original SU(2)xU(1) gauge group [i.e., it is not simply {identity element}xU(1)]. That's what unification means. GUTs seek a larger subgroup for which the SU(3)xSU(2)xU(1) gauge group of the SM is a nontrivial subgroup. Polymathphys (talk) 23:20, 8 March 2009 (UTC)
I'm not confused at all. I'm aware of the poits that you made. My point is that electroweak theory still has two independent coupling constants and therefore isn't unified. Isospin and hypercharge are two non-unified aspects of the electroweak theory. Dauto (talk) 22:28, 9 March 2009 (UTC)
Isospin or weak isospin? Headbomb {ταλκκοντριβς – WP Physics} 10:56, 13 March 2009 (UTC)

equations for the four forces[edit]

i was looking for the equations for the four forces, and didn't find them.Makeswell (talk) 15:15, 25 November 2009 (UTC)

date and unify overview § tags[edit]

The graphic showing the breakdown of particles vs. force carriers is new since the tags were placed. Wrt to the prior thread Field equation seems to be closest but not sure it's that straight forward after gravitation and electromagnetism, whether the latter to be electroweak instead, etc. 72.228.177.92 (talk) 14:54, 17 February 2010 (UTC)

Since nothing there is apparently outside mainstream science, I suggest the tags be removed if no further comment after a month since this is a summary article and the linked ones will have the references. Also it's clear that there are many readers/editors who do in fact have academic credentials as physicists so that (as I presume the prior threads show) this subject has had the requested review. 72.228.177.92 (talk) 01:17, 18 February 2010 (UTC)

Venn Diagram[edit]

Particles by fundamental interactions.png
Elementary particle interactions.svg

I put together a venn diagram of the more well-known particles by the interactions they're subject to. The information was taken from the infoboxes on the particles, and I've uploaded the image to Commons. Can anyone with more expertise than me check the accuracy and integrate it into the article if useful? Image can be found at http://commons.wikimedia.org/wiki/File:Particles_by_fundamental_interactions.png Cranica (talk) 08:20, 4 June 2010 (UTC)

The interactions seem to be correct but harder to understand and less complete than that other picture that is used in the standard model article. Also, it is not clear to me what is the intended meaning for the numbers within the square brackets. Finally, it is really hard to read text written in yellow. Dauto (talk) 15:16, 4 June 2010 (UTC)
Fair enough. The bracketed numbers are footnotes. Cranica (talk) 03:10, 5 June 2010 (UTC)
I suggest making the background outside of the figure black so the colored words can be read better. Andrew Colvin • Talk 01:39, 7 August 2010 (UTC)
Particles by fundamental interactions.svg
I made a svg version of the diagram above. it should give better contrast for the text. --Georg-Johann (talk) 23:46, 27 August 2010 (UTC)


ħ - please explain and simplify[edit]

I was reading this article aloud and I have never seen this symbol: ħ. I have no idea how to pronounce it or say it. Could someone make this article simpler so a non-physicist can understand it and read it aloud? DBlomgren (talk) 03:52, 22 March 2011 (UTC)

The only passage mentioning h-bar is ... "intrinsic angular momentum ±ħ/2, where ħ is the reduced Planck constant". If you want to know what it is, you're only a click away from the answer! Headbomb {talk / contribs / physics / books} 04:32, 22 March 2011 (UTC)

gravitation of disparate masses[edit]

"all objects accelerate toward the Earth at the same rate"

Technically, this can't be true for all objects. A golf ball would not fall toward the Earth at the same rate as the would the planet Jupiter if both were dropped onto the Earth. Objects falling toward Earth exert their own gravitational pull. Verberate (talk) 20:26, 31 March 2011 (UTC)

Clearly it is implied that the object dimensions are small enough that the earth's gravitational field can be considered constant, in which case the statement is true, technically. Dauto (talk) 20:43, 10 May 2011 (UTC)

How small an object would that be? What's the largest object that is still too small to exert any gravitational pull on the Earth? Perhaps the statement should be amended to something like "all objects of at least X mass ..."--Verberate (talk) 20:29, 14 June 2011 (UTC)

I don't think that is necessary. Dauto (talk) 01:27, 15 June 2011 (UTC)


Relative weakness of gravity[edit]

This statement in Fundamental interaction#Gravitation section:

The weakness of gravity can easily be demonstrated by suspending a pin using a simple magnet (such as a refrigerator magnet). The magnet is able to hold the pin against the gravitational pull of the entire Earth.

is very unconvincing because of the incommensurability of mass and charge. Discussing the relative strengths of EM and gravitation with a single charged particle like a proton or electron does make sense as an example of how gravity is much weaker than EM. But it depends on the properties of the particle, such as the charge to mass ratio (charge and mass measured in Planck units). Should this be changed? 70.109.182.97 (talk) 20:01, 15 February 2012 (UTC)

I support the motion that it should be changed but I am not sure how. Like you say, it depends on the particle. You can't lift something more massive, like a car, with the refrigerator magnet, so the demonstration is critically flawed in my opinion. Almo9004 (talk) 21:43, 2 April 2012 (UTC)

Strong/nuclear confusion[edit]

There seems to be some confusion between the strong interaction and the nuclear force on this page. For example, in one of the boxes near the top where the forces are compared it is claimed that the range of interaction for the strong force is about a femtometre, whereas it's actually infinite in range (and, what's more, doesn't decay with distance): the quanta of the strong interaction are gluons, which are massless. However, quarks and gluons are confined into colourless composites, and the "quanta" of the nuclear force (or RESIDUAL strong interaction) are combinations of gluons whose binding gives them mass. So the nuclear force has massive exchange particles and a short-ranged interaction, in much the same way that van der Waals' forces or the forces from a bar magnet fall off more steeply than electrostatic forces despite emerging from the same force. I guess the confusion arises when laypeople ask what the strong interaction is, and the answer is invariably "it's the force that holds nuclei in atoms together". — Preceding unsigned comment added by 131.111.185.74 (talk) 21:25, 1 March 2012 (UTC)

Four fundamental interactions[edit]

Why does the lead say that there are four known fundamental interactions instead of three? Shouldn't the electroweak force be considered a single fundamental interaction? Arc de Ciel (talk) 07:27, 15 May 2012 (UTC)

I thoght that too. Didn't Weinberg win the Nobel for showing that ? Humanpublic (talk) 21:23, 12 October 2012 (UTC)
Electroweak interaction has SU(2) x U(1) structure, which basically means it's two interactions with two gauge fields - weak isospin and weak hypercharge.

Why not 5?[edit]

Shouldn't the Yukawa interaction between two particles (resulting from exchange of a Higgs boson) be included as a fundamental interaction, especially now that the Higgs boson has been discovered? This force (which is always attractive) becomes very significant when considering, at short distances, the interactions of particles that strongly couple to the Higgs (i. e., heavy particles, such as the W, the Z, the top quark, and of course the Higgs itself). 70.99.104.234 (talk) 00:41, 6 July 2012 (UTC)

This article supports the idea that the Higgs interaction is a fifth fundamental interaction: http://profmattstrassler.com/articles-and-posts/particle-physics-basics/the-known-forces-of-nature/the-strength-of-the-known-forces/ --AndreRD (talk) 17:20, 19 March 2014 (UTC)

Gravity is not a weak force for large masses according to Brian Cox[edit]

(I'll rephrase something I said earlier since it's mainly based on his ideas.)

I watched a program of his in which it is stated that since mass bends space in accordance to General Relativity, then in the case of very large stars it becomes a strong force to the point of being able to crush a star to a single nucleus (Neutron Stars) or less (Black Holes).

His argument is that Gravity is a force that scales and that it is not simply a matter of adding individual components and hence to claim it's weak, but that since space is bent in those areas, then gravity as a fundamental force of nature becomes stronger.

--fs 04:08, 28 December 2012 (UTC)

Requested article moves[edit]

The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section.

The result of the move request was: No consensus. This kind of a multi-move should not depend on 2:1 majority. It is better to open a thread at WT:PHYS and try to get opinions there. See a related discussion at WT:WikiProject Physics/Archive January 2013#I think this is a good place to bring this up. In that thread, it is argued that nuclear physicists prefer one term, while particle physicists prefer the other. See a related move discussion from 2006 at Talk:Weak interaction#Move to Weak interaction. EdJohnston (talk) 19:21, 4 July 2013 (UTC)



|current1=Fundamental interaction|new1=Fundamental force|current2=Weak interaction|new2=Weak nuclear force|current3=Strong interaction|new3=Strong nuclear force|}}

– Back in July 2004, this article was moved from Fundamental force. I believe this to be a bad mistake, especially as I can find no sensible discussion prior to the move. I just Googled a few numbers to get an idea of popular usage. "Fundamental force" beats "fundamental interaction" and "strong force" OR "strong nuclear force" beats "strong interaction". "Weak interaction just pips "weak force" OR "weak nuclear force", however given that the Internet scrapes our article titles so frequently and our article on the weak force is titled "weak interaction", that doesn't mean much. The article on the weak interaction in particular has been criticised in a letter to New Scientist magazine (11 May 2013, p.30) as unintelligible to the lay reader. The lay reader is far more at ease with the idea of forces than interactions, and I'd suggest that is more important than any pedantic pedagoguery. — Cheers, Steelpillow (Talk) 11:58, 24 June 2013 (UTC)

How much force does the weak force exert on anything? Do you have a measurement for this? Hcobb (talk) 13:22, 24 June 2013 (UTC)
No. Perhaps you in turn can explain why so many scientists refer to the "four fundamental forces" - 1,420,000 Google hits vs. 252,000 for "four fundamental interactions" - when, as you say, they aren't all forces in the Newtonian sense of the word? — Cheers, Steelpillow (Talk) 14:41, 24 June 2013 (UTC) [Update] For example Stephen Hawking, writing in A brief history of time, Bantam (1988), pages 70-71, explains each of these "forces" in turn. If "force" is good enough for him, I'd suggest it's good enough for Wikipedia. C.f. WP:NOTTEXTBOOK. — Cheers, Steelpillow (Talk) 14:57, 24 June 2013 (UTC)
  • Support move to fundamental force; neutral for now on the other proposed moves. I did an ngram of these six titles here. It can't really be trusted for strong interaction or weak interaction because those have common-English possible meanings, too (imagine "for a marriage to work, there must be strong interaction between husband and wife" or something like that). I can't take a conclusion for those two titles. However, the ngram is pretty clear that "fundamental force" is more common (both "fundamental force" and "fundamental interaction" could likewise be used in running text; however, when you capitalize "fundamental" you again get more results for the "force" version.) Anyway, the only one clear enough for me right now is the fundamental move. Red Slash 17:54, 24 June 2013 (UTC)
    I'd hate to see us move an incomplete set of pages - worst of both worlds IMHO. Meanwhile, the ngram here comparing "four fundamental forces" with "four fundamental interactions" is also instructive. Less room for ambiguity, too. — Cheers, Steelpillow (Talk) 18:50, 24 June 2013 (UTC)
  • Oppose "strong interaction" move, since in many works, "strong nuclear force" and "strong force" usually means residual strong force and not the color force -- 65.94.79.6 (talk) 00:49, 25 June 2013 (UTC)
The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.