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As my other questions also point out, I study this for fun. I am in no university yet.

as the title (hopefully summarizes), my question is this:

is these words(or terms,) the same?

  • gravity
  • gravitation
  • gravitational force

I have also 1 additional smaller question (but it is related to this so I put this question here as well ) and that is,

  • Is gravity a force? ( described in both Wikipedia and in the book, it is a force)

But I have always been confused "is it a force or not?", because I know in Einstein's General Relativity, Gravity is not really a "force" per say, but the space-time's curvature by the presence of mass.

What I think

note: I do think the last one (gravitational force) is a way of emphasizing the force itself (and, the other 2 gravity , gravitation is 2 more "general" terms, maybe used in day-to-day)

for example, one tend to say.. Something on those lines(making this example up):

the gravity is weak here right?

and not

the gravitational force is weak here right?

From sources

according to Wikipedia, all these terms is "the same" as I get redirected from searching all these terms , into this single Wikipedia site 'Gravity'

And, this shows it too, which makes me a bit confused:

In physics, gravity (from Latin gravitas 'weight'1) is a fundamental interaction

And when I go to this Fundamental_interaction link, it states:

fundamental interactions, also known as fundamental forces it is a force.

From other sources

Being a very careful reader, I always try to find the same information I'm asking about but in a entirely different place. In this case it is from

  • Chapter 13 "Gravitation" , page 331, in book: "Fundamentals of physics 7th edition" by Halliday/Resnick/Walker

One of the long-standing goals of physics is to understand the gravitational force

NOTE to be clear

  • This is not a homework question, I am just using this book to describe the same question but from a different source, as-to not only rely on 1 source(Wikipedia)

As 1 of my previous questions, which was Confused on the types of solutions to Einstein field equations in General Relativity, this question is nearly identical to it except the terms is different.

Resources I have tried

After re-researching the site I did find some related links, but the confusion still remains, I guess it is expressed as "being a force" and "not being a force" depending on "which subject we are in" (Newtonian/classical mechanics) or (relativity/spacetime).

note, the above is broadly speaking.

Related links

Being unsure, I added tags General Relativity and Classical Mechanics, because maybe gravity is just described differently in different 'subjects' (I don't know, which is why I ask)

Thanks!

External Links

as Anna v commented, this is also a great related link

William Martens
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2 Answers2

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There is simply no one answer to this question. Different authors will mean different things by these terms. You will need to evaluate each source to understand what exactly the individual author means.

Personally, I usually intend the following usage. My usage is common but not ubiquitous:

Gravity: the gravitational force. (Other authors commonly use it to mean the entire class of phenomena)

Gravitation: the entire class of phenomena. (Other authors occasionally use it to mean motion, like orbits or projectile motion)

Gravitational force: this one is pretty standardized. It refers to the gravitational acceleration times the mass.

Is gravity a force?

Yes and no. In standard Newtonian mechanics it is. In General relativity and Newton-Cartan gravity it is a fictitious force locally.

Dale
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    Thanks so much, even though it was a small question (well, actually 2 questions), thanks! it cleared it up! – William Martens Jan 04 '23 at 14:27
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    @WilliamMartens no complaints about the question from my side. It was well written, and clear – Dale Jan 04 '23 at 14:29
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    for you this might be just a 2nd thank you from my side but; this is actually a real comment: thanks for the reply; I will continue to follow this format next time I have questions, :thumbs up: – William Martens Jan 04 '23 at 14:32
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I would rather suggest to think about gravity (and all other interactions) as fields (classical fields, quantum fields, probability fields, scalar & tensor fields, spacetime-curvature and whatnot). Then force would be just a field application to the body immersed into the field.

Agnius Vasiliauskas
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