A question from Quora:
Why do physicists still talk about the force of gravity and the graviton when Einstein showed it to be a curvature of spacetime?
In spite of the condescending tone of some of the answers, I think this is a good question, not least because physicists seem to have fundamental differences in how they answer it.
The Rev Dodgson said:
A question from Quora:Why do physicists still talk about the force of gravity and the graviton when Einstein showed it to be a curvature of spacetime?
In spite of the condescending tone of some of the answers, I think this is a good question, not least because physicists seem to have fundamental differences in how they answer it.
It has a far reaching influence so would be considered a force wouldn’t it
Cymek said:
The Rev Dodgson said:
A question from Quora:Why do physicists still talk about the force of gravity and the graviton when Einstein showed it to be a curvature of spacetime?
In spite of the condescending tone of some of the answers, I think this is a good question, not least because physicists seem to have fundamental differences in how they answer it.
It has a far reaching influence so would be considered a force wouldn’t it
Looks like it broke the forum.
I guess it must be a force.
The Rev Dodgson said:
Cymek said:
The Rev Dodgson said:
A question from Quora:Why do physicists still talk about the force of gravity and the graviton when Einstein showed it to be a curvature of spacetime?
In spite of the condescending tone of some of the answers, I think this is a good question, not least because physicists seem to have fundamental differences in how they answer it.
It has a far reaching influence so would be considered a force wouldn’t it
Looks like it broke the forum.
I guess it must be a force.
It’s strange its influence is what creates solar systems amongst other things but we need highly sensitive equipment to detect gravity waves from two massive objects merging.
Einstein’s curved space-time is all very neat and has been experimentally confirmed, but it doesn’t actually explain the mechanism of gravity.
Force and space-time are not well defined. Quantum effects are not included.
Disclaimer: I not fizzisist.
Einstein’s curved space-time is all very neat and has been experimentally confirmed, but it doesn’t actually explain the mechanism of gravity.
Force and space-time are not well defined. Quantum effects are not included.
Disclaimer: I not fizzisist.
> Looks like it broke the forum.
No, I’m just having a day off.
mollwollfumble said:
> Looks like it broke the forum.No, I’m just having a day off.
:)
dv dropped in and ignored this thread as well.
But then he doesn’t approve of Quora.
them says it’sn’t really a question of physics though, seems
SCIENCE said:
them says it’sn’t really a question of physics though, seems
I don’t really follow.
Why isn’t it a question of physics?
The Rev Dodgson said:
A question from Quora:Why do physicists still talk about the force of gravity and the graviton when Einstein showed it to be a curvature of spacetime?
In spite of the condescending tone of some of the answers, I think this is a good question, not least because physicists seem to have fundamental differences in how they answer it.
The answers are good. I strongly dislike it when people say that centrifugal force doesn’t exist. It does exist. It’s the force on the person holding the string that has a swinging weight on the other end. It just comes down to frame of reference.
Similarly, the force of gravity does exist. Again, it just comes down to frame of reference. Just because the gravity appears in a different part of the equations of GR to electromagnetism doesn’t mean that they’re not both forces.
> Here’s the deal with gravitons…the graviton is not, strictly speaking, a “theoretical” particle, because there’s no theory yet that predicts its existence.
I’m going to split hairs here and say that the graviton must exist, even though there’s as yet no consistent confirmed theory that explains all its properties. The graviton pops straight out of quantum field theory (see the book A. Zee “Quantum Field theory in a nutshell) as well as being a prediction of every type of string theory. Quantum field theory is confirmed, but it’s description of the graviton is not consistent with GR. String theory’s prediction of the graviton is self-consistent and consistent with GR, but string theory is not confirmed.
> Paul Calhoun Waser, M.S. Engineering Mechanics & Relativity (1962)
His answers are as archaic as “relativistic mass”.
> Tiberiu Tesileanu, PhD string theory … Let’s start closer to home: the centrifugal force.
Hey, that’s what I said! Well put, Tiberiu Tesileanu, I find myself in total agreement.
Every reaction has an equal and opposite reaction.
The inward centripetal force is balanced by the outward centrifugal force.
For an apple in a tree. The downward force of the apple on the tree is balanced by the upward force of the tree on the apple. The downward force of a standing human on the ground is balanced by the upward force of the ground on the human.
What do we call the upward force due to gravity?
mollwollfumble said:
Every reaction has an equal and opposite reaction.The inward centripetal force is balanced by the outward centrifugal force.
For an apple in a tree. The downward force of the apple on the tree is balanced by the upward force of the tree on the apple. The downward force of a standing human on the ground is balanced by the upward force of the ground on the human.
What do we call the upward force due to gravity?
In my opinion a force is an interaction between two objects, so is both an action and reaction; it’s not two separate forces.
But for those who like to describe this interaction as two separate forces, the gravitational reaction force is called gravitational reaction force, isn’t it?
mollwollfumble said:
The Rev Dodgson said:
A question from Quora:Why do physicists still talk about the force of gravity and the graviton when Einstein showed it to be a curvature of spacetime?
In spite of the condescending tone of some of the answers, I think this is a good question, not least because physicists seem to have fundamental differences in how they answer it.
The answers are good. I strongly dislike it when people say that centrifugal force doesn’t exist. It does exist. It’s the force on the person holding the string that has a swinging weight on the other end. It just comes down to frame of reference.
Similarly, the force of gravity does exist. Again, it just comes down to frame of reference. Just because the gravity appears in a different part of the equations of GR to electromagnetism doesn’t mean that they’re not both forces.
> Here’s the deal with gravitons…the graviton is not, strictly speaking, a “theoretical” particle, because there’s no theory yet that predicts its existence.
I’m going to split hairs here and say that the graviton must exist, even though there’s as yet no consistent confirmed theory that explains all its properties. The graviton pops straight out of quantum field theory (see the book A. Zee “Quantum Field theory in a nutshell) as well as being a prediction of every type of string theory. Quantum field theory is confirmed, but it’s description of the graviton is not consistent with GR. String theory’s prediction of the graviton is self-consistent and consistent with GR, but string theory is not confirmed.
> Paul Calhoun Waser, M.S. Engineering Mechanics & Relativity (1962)
His answers are as archaic as “relativistic mass”.
> Tiberiu Tesileanu, PhD string theory … Let’s start closer to home: the centrifugal force.
Hey, that’s what I said! Well put, Tiberiu Tesileanu, I find myself in total agreement.
Missed this one.
I agree, of course the centrifugal force on an object moving in a curved path is a real force.
I think the confusion comes from when the observer is travelling on a curved path and sees an object travelling in a straight line. To the observer the object appears to be accelerating outwards, so in that case there really is an imaginary outward force.
The Rev Dodgson said:
mollwollfumble said:
Every reaction has an equal and opposite reaction.The inward centripetal force is balanced by the outward centrifugal force.
For an apple in a tree. The downward force of the apple on the tree is balanced by the upward force of the tree on the apple. The downward force of a standing human on the ground is balanced by the upward force of the ground on the human.
What do we call the upward force due to gravity?
Missed this one.I agree, of course the centrifugal force on an object moving in a curved path is a real force.
I think the confusion comes from when the observer is travelling on a curved path and sees an object travelling in a straight line. To the observer the object appears to be accelerating outwards, so in that case there really is an imaginary outward force.
—
In my opinion a force is an interaction between two objects, so is both an action and reaction; it’s not two separate forces.But for those who like to describe this interaction as two separate forces, the gravitational reaction force is called gravitational reaction force, isn’t it?
For first half – that makes sense.
For second half – “gravitational reaction force” is better than anything I thought of. If in liquid or gas we’d call it buoyancy.