# Is it possible that the Strong Force and gravity are the same thing?

## Main Question or Discussion Point

Because the Strong Force and gravity are both forces that attract, could they actually be the same thing, manifesting in different ways at different distances?

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Bobbywhy
Gold Member
PeterLouis, Welcome to Physics Forums!

True, both the Strong Force and Gravity are attractive forces. But they seem to have hugely different strengths and also, the S.F. only acts over tiny distances. G. acts over astronomical distances.

I have no source material - actually just thought of this question, which seems to be pretty basic, but can find no discussion of it on the internet.
And, thanks for making me feel welcome!

Agreed that these two forces "have hugely different strengths," etc., but is there any possible way they can be the same thing in different iterations? Whether the answer is "no," "we don't know" or "maybe," I would love an explanation.

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Bobbywhy
Gold Member
PeterLouis, Google is your friend. Never before has mankind (that means you and I) had so much information at our fingertips! We live in the information age, and you can become a part of it. Learn how to find stuff and you will learn lots. As you progress you will begin to recognize the whackos and crackpots who post BS, and just ignore them. It is easy to find reliable sources you can trust to give the straight scoop on scientific questions. For example, using Google I found these four sites concerning the "strong force":

http://en.wikipedia.org/wiki/Strong_interaction
http://en.wikipedia.org/wiki/Nuclear_force
http://aether.lbl.gov/elements/stellar/strong/strong.html
http://hyperphysics.phy-astr.gsu.edu/hbase/forces/funfor.html

Just to get you started, I suggest the last one first, then the other three.

Then, when you are finished, Google "gravity" and compare the two. I am confident you can decide if they are "the same thing in different iterations" or not. If you have any questions or doubts about what you find, then come right back here and post them. Members here are always ready to help if they can.
Cheers,
Bobbywhy

Hi members.
I was thinking that there is two differences between the two.
1. S.F. doesn't follow inverse square law WHILE G. follows it.
2. G. Force is conservative in nature but for the strong force it is not found yet.

Because the Strong Force and gravity are both forces that attract, could they actually be the same thing, manifesting in different ways at different distances?
Hello!

I've heard suggestions (e.g. Griffits in his "Introduction to Elementary Particles") that if singlet gluon could be photon itself then it would be beautiful unification of the electrodynamics with strong force, but have never actually heard of suggestion that it's connected to gravity. I think this line of thought is a dead end.

ZapperZ
Staff Emeritus
2018 Award
Because the Strong Force and gravity are both forces that attract, could they actually be the same thing, manifesting in different ways at different distances?
I have no source material - actually just thought of this question, which seems to be pretty basic, but can find no discussion of it on the internet.
And, thanks for making me feel welcome!

Agreed that these two forces "have hugely different strengths," etc., but is there any possible way they can be the same thing in different iterations? Whether the answer is "no," "we don't know" or "maybe," I would love an explanation.
In both of your posts, you have provided no reasons for your thinking on why they should be the same thing. Instead, everyone else has brought the characteristics of the two that make them VERY different.

This is not how we do science, I.e. by shooting at things in the dark. If you cannot provide source material or rational reasons for something, then you are making baseless speculation, which in violation of the PF rules.

Zz.

ZapperZ: If we lived in the 15th century and I asked, "Could the world be round?" would you tell me that is not how we do science?

Bobbywhy: There is nothing on any of the sites you mentioned that specifically addresses the question I posed.

I asked a legitimate, and obvious question and am being criticized for asking it. Yet there is no clear response.

The physical theories of gravity and the strong force are very different. For instance, the strong force is described by QCD which is a quantum field theory and gravity is described by the non-quantum theory of general relativity. I would say there is clear response to your question among physicists - gravity and QCD are not the same thing. People with more insight in these theories will be able to provide you with good explanations of the differences between the theories. What is vague in the answers you have received?

Kloptok: Thank you - although details are still wanting.
While these two forces have very different evident characteristics, note the way the question asked: "is it possible..." The fact that they ultimately do the same thing, begs the question.

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Nabeshin
Kloptok: Thank you - although details are still wanting.
While these two forces have very different evident characteristics, note the way the question asked: "is it possible..." The fact that they ultimately do the same thing, begs the question.
It actually doesn't beg the question. Just because two things have one property in common doesn't really suggest that they're the same, but OK suppose you want to pursue that line. Like has been said above, we know the description of the strong force in terms of QCD, no such description exists for gravity. One can go into a long description along this lines, but I don't want to go into it here. One striking feature is that gravity is manifestly long ranged, while the strong force obviously is not. This alone tells you there is something fundamentally different about the two forces.

You can always ask 'is it possible...' no matter how robust our understanding of physics is. The nature of science is not to ever absolutely exclude such things, but at a certain point the question becomes extremely unproductive. And unless you are talking about some grand unified theory (which I highly suspect you were not, judging by your posts), we're at that point for the low energy description of the strong force and gravity.

ZapperZ: If we lived in the 15th century and I asked, "Could the world be round?" would you tell me that is not how we do science?
Probably, since even Ancient Greeks knew that the Earth is round. See Erathostenes.

I fear that I am becoming a nuisance. Nevertheless:

Nabeshin:
The one property they have in common - they each attract mass - is the very thing that determines them to be fundamental forces - so whether they are actually different, or somehow just different expressions of the same thing, goes to the heart of the matter. Despite the fact of their obvious differences, obvious similarities are glaring

Regarding "descriptions," I refer you to the parable of the blind men describing an elephant: The blind man who feels a leg says the elephant is like a pillar; the one who feels the tail says the elephant is like a rope, etc.

Differing descriptions does not establish dissimilarity.

Ryan_m_b
Staff Emeritus
I fear that I am becoming a nuisance. Nevertheless:

Nabeshin:
The one property they have in common - they each attract mass - is the very thing that determines them to be fundamental forces - so whether they are actually different, or somehow just different expressions of the same thing, goes to the heart of the matter. Despite the fact of their obvious differences, obvious similarities are glaring

Regarding "descriptions," I refer you to the parable of the blind men describing an elephant: The blind man who feels a leg says the elephant is like a pillar; the one who feels the tail says the elephant is like a rope, etc.

Differing descriptions does not establish dissimilarity.
There's nothing with asking questions so long as you take on board the answers. To use your own analogy, you are the blind man grabbing an elephant leg in one hand and a pillar in the other and not listening to the people with sight telling you why they are not the same.

As for your blind men describing an elephant, we do have some suspicion that all four (three now) fundamental forces are manifestations of the same one, though we're pretty sure we should unify the Electroweak and Strong forces before we unify that with Gravity.

Another obvious difference is the fact that Gravity and the Strong force have different charges.

Nugatory
Mentor
ZapperZ: If we lived in the 15th century and I asked, "Could the world be round?" would you tell me that is not how we do science?
Probably not, because the scientific method was far less understood then.

But if we were to apply the scientific method in that context, the answer you would hear would indeed be: "Yes, it is possible that the Earth is round, but that's not how we do science."

Now, if you were to try statements along the lines of:
- "If the world were round, it would be possible to sail east and come back to your starting point from the west - and somehow you'd have recorded the passage of one fewer day - that would be an interesting experiment that would tell us something about the shape of the earth".
- "If the world were round, that would explain why its shadow on the moon appears curved during a lunar eclipse - we've looked at the eclipse last night, and damned if the shadow wasn't curved".
- "If the world is round, there should be places where the sun is precisely exactly overhead at noon. Do we know of any, or could we find some?" (One of the reasons the Greeks believed the earth was round is that they had found such a place).

you'd get a very different and much more open reception from the (hypothetical) 15th-century scientific community.

The strong force acts only on quarks and gluons. The gravity acts on everything. There's a huge difference right there.

Ryan M B: you are telling me to "just believe" people who know more then me, without offering details.

Aside from differences based on distance, in this whole discussion, only two facts have been stated explaining why these two forces couldn't be the same:
1) Gravity and the Strong force have different charges
2) S.F. doesn't follow inverse square law WHILE G. follows it.

This is not enough proof to overcome the presumption of similarity based on observation.

Gravity and EMF clearly do different things. One is an apple and one is a zebra.
Gravity and SF look like they do the same thing: attract. Perhaps one is a Red Delicious and one is a Macintosh (no pun intended). While I am not advocating any position, the burden of proof is on those advocating positions which refute observable truth: that they both are apples.

This thread deserves to be deleted.

This thread deserves to be deleted.
When did science become so antagonistic to questions "outside the box"?
If this is such a silly question, where is conclusive answer?

Ryan_m_b
Staff Emeritus
Ryan M B: you are telling me to "just believe" people who know more then me, without offering details.
I am not telling you to just believe at all, I am telling you to listen to the answers you are given. Ask specific questions about what you don't understand. Be polite and be prepared to learn. Quoting parables at people and acting in an arrogant manner, insisting that your idea has merit even though you have no reason to think so is not a good attitude to have.
When did science become so antagonistic to questions "outside the box"?
If this is such a silly question, where is conclusive answer?
When you are confronted by people who know what they are talking about and have become frustrated with you for a reason that eludes you it is rarely good to play the "I'm thinking outside the box, you experts don't have my level of understanding" card. People are here on this sight to answer questions and share knowledge of science, they do it hundreds of times every day. For you to be this insulting and expect people to help you after is baffling.

Now I hope this thread doesn't have to be locked. If you are prepared to ask questions and listen to the answers rather than repeating your idea and insulting the volunteers giving up their time to help you then you will realise that this site is a great resource.

No insult was intended - pardon me if it came off that way. I very much appreciate the time you are taking. I am here to learn and you are volunteering to help me with that.

To the eyes of this "innocent" there seems to be a contradiction - or at least a conclusion, that is not justified by the documentation. I have searched the internet and the links provided, and carefully examined the suggestions provided here, but clear details that address my question are pending.

Ryan_m_b
Staff Emeritus
No insult was intended - pardon me if it came off that way. I very much appreciate the time you are taking. I am here to learn and you are volunteering to help me with that.

To the eyes of this "innocent" there seems to be a contradiction - or at least a conclusion, that is not justified by the documentation. I have searched the internet and the links provided, and carefully examined the suggestions provided here, but clear details that address my question are pending.
Given that lets start afresh, how about you read over the replies you've been given and respond to the specific points so that people know what questions to address?

Thank you.

(From an earlier post, copied here) I believe this has the information you just requested:

"Aside from differences based on distance, in this whole discussion, only two facts have been stated explaining why these two forces couldn't be the same:
1) Gravity and the Strong force have different charges
2) S.F. doesn't follow inverse square law WHILE G. follows it.

This is not enough proof to overcome the presumption of similarity based on observation.

Gravity and EMF clearly do different things. One is an apple and one is a zebra.
Gravity and SF look like they do the same thing: attract. Perhaps one is a Red Delicious and one is a Macintosh (no pun intended). While I am not advocating any position, the burden of proof is on those advocating positions which refute observable truth: that they both are apples."

I like this question, and I think there is some merit to wondering if 'gravity' manifests itself differently at small scales. The inverse square law may only be an approximation at large scales just as vector velocities are to special relativity.