Do theoretical physics suggest that gravity is the exchange of gravitons or deformation/bending of spacetime?












6












$begingroup$


Throughout my life, I have always been taught that gravity is a simple force, however now I struggle to see that being strictly true.



Hence I wanted to ask what modern theoretical physics suggests about this: is gravity the exchange of the theoretical particle graviton or rather a 'bend' in space due to the presence of matter?



I don't need a concrete answer, but rather which side the modern physics and research is leaning to.



Thank You










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steve_just_steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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  • $begingroup$
    I think that whichever model suits your need the best should get the job done. But then again I am not a Physicist.
    $endgroup$
    – harshit54
    5 hours ago










  • $begingroup$
    Well, even if you are not a physicist this is still a good point, so thank you.
    $endgroup$
    – steve_just_steve
    5 hours ago










  • $begingroup$
    @steve_jyst_steve: I was struggling to understand what was being asked here, so I took a moment to correct the grammar and phrasing. If you’re not happy with that, please just roll-back.
    $endgroup$
    – Mozibur Ullah
    41 mins ago










  • $begingroup$
    @MoziburUllah Hello, and thank you very much for doing that, definitely sound better now!
    $endgroup$
    – steve_just_steve
    38 mins ago










  • $begingroup$
    An article in the New Yorker about looking at the same "thing" using different stances: A Different Kind of Theory of Everything (via Peter Woit's blog)
    $endgroup$
    – David Tonhofer
    7 mins ago
















6












$begingroup$


Throughout my life, I have always been taught that gravity is a simple force, however now I struggle to see that being strictly true.



Hence I wanted to ask what modern theoretical physics suggests about this: is gravity the exchange of the theoretical particle graviton or rather a 'bend' in space due to the presence of matter?



I don't need a concrete answer, but rather which side the modern physics and research is leaning to.



Thank You










share|cite|improve this question









New contributor




steve_just_steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.







$endgroup$












  • $begingroup$
    I think that whichever model suits your need the best should get the job done. But then again I am not a Physicist.
    $endgroup$
    – harshit54
    5 hours ago










  • $begingroup$
    Well, even if you are not a physicist this is still a good point, so thank you.
    $endgroup$
    – steve_just_steve
    5 hours ago










  • $begingroup$
    @steve_jyst_steve: I was struggling to understand what was being asked here, so I took a moment to correct the grammar and phrasing. If you’re not happy with that, please just roll-back.
    $endgroup$
    – Mozibur Ullah
    41 mins ago










  • $begingroup$
    @MoziburUllah Hello, and thank you very much for doing that, definitely sound better now!
    $endgroup$
    – steve_just_steve
    38 mins ago










  • $begingroup$
    An article in the New Yorker about looking at the same "thing" using different stances: A Different Kind of Theory of Everything (via Peter Woit's blog)
    $endgroup$
    – David Tonhofer
    7 mins ago














6












6








6


3



$begingroup$


Throughout my life, I have always been taught that gravity is a simple force, however now I struggle to see that being strictly true.



Hence I wanted to ask what modern theoretical physics suggests about this: is gravity the exchange of the theoretical particle graviton or rather a 'bend' in space due to the presence of matter?



I don't need a concrete answer, but rather which side the modern physics and research is leaning to.



Thank You










share|cite|improve this question









New contributor




steve_just_steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.







$endgroup$




Throughout my life, I have always been taught that gravity is a simple force, however now I struggle to see that being strictly true.



Hence I wanted to ask what modern theoretical physics suggests about this: is gravity the exchange of the theoretical particle graviton or rather a 'bend' in space due to the presence of matter?



I don't need a concrete answer, but rather which side the modern physics and research is leaning to.



Thank You







gravity spacetime curvature quantum-gravity carrier-particles






share|cite|improve this question









New contributor




steve_just_steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|cite|improve this question









New contributor




steve_just_steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|cite|improve this question




share|cite|improve this question








edited 45 mins ago









Mozibur Ullah

4,94432252




4,94432252






New contributor




steve_just_steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









asked 5 hours ago









steve_just_stevesteve_just_steve

385




385




New contributor




steve_just_steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





New contributor





steve_just_steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






steve_just_steve is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.












  • $begingroup$
    I think that whichever model suits your need the best should get the job done. But then again I am not a Physicist.
    $endgroup$
    – harshit54
    5 hours ago










  • $begingroup$
    Well, even if you are not a physicist this is still a good point, so thank you.
    $endgroup$
    – steve_just_steve
    5 hours ago










  • $begingroup$
    @steve_jyst_steve: I was struggling to understand what was being asked here, so I took a moment to correct the grammar and phrasing. If you’re not happy with that, please just roll-back.
    $endgroup$
    – Mozibur Ullah
    41 mins ago










  • $begingroup$
    @MoziburUllah Hello, and thank you very much for doing that, definitely sound better now!
    $endgroup$
    – steve_just_steve
    38 mins ago










  • $begingroup$
    An article in the New Yorker about looking at the same "thing" using different stances: A Different Kind of Theory of Everything (via Peter Woit's blog)
    $endgroup$
    – David Tonhofer
    7 mins ago


















  • $begingroup$
    I think that whichever model suits your need the best should get the job done. But then again I am not a Physicist.
    $endgroup$
    – harshit54
    5 hours ago










  • $begingroup$
    Well, even if you are not a physicist this is still a good point, so thank you.
    $endgroup$
    – steve_just_steve
    5 hours ago










  • $begingroup$
    @steve_jyst_steve: I was struggling to understand what was being asked here, so I took a moment to correct the grammar and phrasing. If you’re not happy with that, please just roll-back.
    $endgroup$
    – Mozibur Ullah
    41 mins ago










  • $begingroup$
    @MoziburUllah Hello, and thank you very much for doing that, definitely sound better now!
    $endgroup$
    – steve_just_steve
    38 mins ago










  • $begingroup$
    An article in the New Yorker about looking at the same "thing" using different stances: A Different Kind of Theory of Everything (via Peter Woit's blog)
    $endgroup$
    – David Tonhofer
    7 mins ago
















$begingroup$
I think that whichever model suits your need the best should get the job done. But then again I am not a Physicist.
$endgroup$
– harshit54
5 hours ago




$begingroup$
I think that whichever model suits your need the best should get the job done. But then again I am not a Physicist.
$endgroup$
– harshit54
5 hours ago












$begingroup$
Well, even if you are not a physicist this is still a good point, so thank you.
$endgroup$
– steve_just_steve
5 hours ago




$begingroup$
Well, even if you are not a physicist this is still a good point, so thank you.
$endgroup$
– steve_just_steve
5 hours ago












$begingroup$
@steve_jyst_steve: I was struggling to understand what was being asked here, so I took a moment to correct the grammar and phrasing. If you’re not happy with that, please just roll-back.
$endgroup$
– Mozibur Ullah
41 mins ago




$begingroup$
@steve_jyst_steve: I was struggling to understand what was being asked here, so I took a moment to correct the grammar and phrasing. If you’re not happy with that, please just roll-back.
$endgroup$
– Mozibur Ullah
41 mins ago












$begingroup$
@MoziburUllah Hello, and thank you very much for doing that, definitely sound better now!
$endgroup$
– steve_just_steve
38 mins ago




$begingroup$
@MoziburUllah Hello, and thank you very much for doing that, definitely sound better now!
$endgroup$
– steve_just_steve
38 mins ago












$begingroup$
An article in the New Yorker about looking at the same "thing" using different stances: A Different Kind of Theory of Everything (via Peter Woit's blog)
$endgroup$
– David Tonhofer
7 mins ago




$begingroup$
An article in the New Yorker about looking at the same "thing" using different stances: A Different Kind of Theory of Everything (via Peter Woit's blog)
$endgroup$
– David Tonhofer
7 mins ago










2 Answers
2






active

oldest

votes


















13












$begingroup$

Both.



General relativity describes gravity as curvature of spacetime, and general relativity is an extremely successful theory. Its correct predictions about gravitational waves, as verified directly by LIGO, are especially severe tests.



Gravity also has to be quantum-mechanical, because all the other forces of nature are quantum-mechanical, and when you try to couple a classical (i.e., non-quantum-mechanical) system to a quantum-mechanical one, it doesn't work. See Carlip and Adelman for a discussion of this.



So we know that gravity has to be described both as curvature of spacetime and as the exchange of gravitons. That's not inherently a contradiction. We do similar things with the other forces. We just haven't been able to make it work for gravity.



Carlip, "Is Quantum Gravity Necessary?," http://arxiv.org/abs/0803.3456



Adelman, "The Necessity of Quantizing Gravity," http://arxiv.org/abs/1510.07195






share|cite|improve this answer









$endgroup$













  • $begingroup$
    Hey man, the links you sent are very useful and this really helped clear up certain misconceptions I had about gravity, so it can and in fact is very likely to be both. Thank you very much :-) !!
    $endgroup$
    – steve_just_steve
    2 hours ago






  • 3




    $begingroup$
    This is probably a naive question, but wouldn't gravitons also produce gravitational waves, since the other forces do, e.g. EM waves?
    $endgroup$
    – gardenhead
    51 mins ago










  • $begingroup$
    @gardenhead physics.stackexchange.com/questions/215173/… This suggests that gravitons are to gravitational waves as photons are to electromagnetic waves. So if my understanding is correct (don't bet on it, I mostly know classical physics), it is more like saying the graviton is the carrier on the quantum level for the gravatational waves.
    $endgroup$
    – JMac
    25 mins ago



















1












$begingroup$

Gravity is as simple a force as all the others, which means that its simple when not looked at too closely, and far more sophisticated when it is. Given that it’s generally supposed all forces are merely low energy relics of a single high energy one, we might suppose that all the forces are as complicated as each other when looked at closely.



Popularly, Gravity is seen as different from the other forces in that its geometric. It turns out that the other forces are also geometric. Nevertheless, the main difference is that in gravity, the metric tensor, which tells us how to measure distances, times and angles is directly implicated in a way that it isn’t in the other forces. For example, there are two equations in EM, one of which does not involve the metric and hence seen as topological, and the other, which does (via the Hodge star) and hence, is coupled with gravity. The other two forces, the weak and strong force are modelled as gauge theories of the Yang-Mills type and hence directly generalising the EM equations. So similarly, they also have a topological and metric aspect, and the latter means it couples to gravity.



Now, whilst gravity hasn’t yet been quantised with several ongoing major projects that attempt this there are several partial semi-classical results which are used to help orientate research into this. One such result is that the quanta of gravity, the graviton, is a massless spin-2 particle. This is understood by looking at a linearisation of gravity which is used in the theory of gravitational radiation, and then by quantising this to show we have a massless spin-2 particle, aka the graviton.






share|cite|improve this answer









$endgroup$













  • $begingroup$
    Thank you very much for your answer! Linearisation of gravity is definitely something to look into for me :-)!
    $endgroup$
    – steve_just_steve
    48 mins ago











Your Answer





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2 Answers
2






active

oldest

votes








2 Answers
2






active

oldest

votes









active

oldest

votes






active

oldest

votes









13












$begingroup$

Both.



General relativity describes gravity as curvature of spacetime, and general relativity is an extremely successful theory. Its correct predictions about gravitational waves, as verified directly by LIGO, are especially severe tests.



Gravity also has to be quantum-mechanical, because all the other forces of nature are quantum-mechanical, and when you try to couple a classical (i.e., non-quantum-mechanical) system to a quantum-mechanical one, it doesn't work. See Carlip and Adelman for a discussion of this.



So we know that gravity has to be described both as curvature of spacetime and as the exchange of gravitons. That's not inherently a contradiction. We do similar things with the other forces. We just haven't been able to make it work for gravity.



Carlip, "Is Quantum Gravity Necessary?," http://arxiv.org/abs/0803.3456



Adelman, "The Necessity of Quantizing Gravity," http://arxiv.org/abs/1510.07195






share|cite|improve this answer









$endgroup$













  • $begingroup$
    Hey man, the links you sent are very useful and this really helped clear up certain misconceptions I had about gravity, so it can and in fact is very likely to be both. Thank you very much :-) !!
    $endgroup$
    – steve_just_steve
    2 hours ago






  • 3




    $begingroup$
    This is probably a naive question, but wouldn't gravitons also produce gravitational waves, since the other forces do, e.g. EM waves?
    $endgroup$
    – gardenhead
    51 mins ago










  • $begingroup$
    @gardenhead physics.stackexchange.com/questions/215173/… This suggests that gravitons are to gravitational waves as photons are to electromagnetic waves. So if my understanding is correct (don't bet on it, I mostly know classical physics), it is more like saying the graviton is the carrier on the quantum level for the gravatational waves.
    $endgroup$
    – JMac
    25 mins ago
















13












$begingroup$

Both.



General relativity describes gravity as curvature of spacetime, and general relativity is an extremely successful theory. Its correct predictions about gravitational waves, as verified directly by LIGO, are especially severe tests.



Gravity also has to be quantum-mechanical, because all the other forces of nature are quantum-mechanical, and when you try to couple a classical (i.e., non-quantum-mechanical) system to a quantum-mechanical one, it doesn't work. See Carlip and Adelman for a discussion of this.



So we know that gravity has to be described both as curvature of spacetime and as the exchange of gravitons. That's not inherently a contradiction. We do similar things with the other forces. We just haven't been able to make it work for gravity.



Carlip, "Is Quantum Gravity Necessary?," http://arxiv.org/abs/0803.3456



Adelman, "The Necessity of Quantizing Gravity," http://arxiv.org/abs/1510.07195






share|cite|improve this answer









$endgroup$













  • $begingroup$
    Hey man, the links you sent are very useful and this really helped clear up certain misconceptions I had about gravity, so it can and in fact is very likely to be both. Thank you very much :-) !!
    $endgroup$
    – steve_just_steve
    2 hours ago






  • 3




    $begingroup$
    This is probably a naive question, but wouldn't gravitons also produce gravitational waves, since the other forces do, e.g. EM waves?
    $endgroup$
    – gardenhead
    51 mins ago










  • $begingroup$
    @gardenhead physics.stackexchange.com/questions/215173/… This suggests that gravitons are to gravitational waves as photons are to electromagnetic waves. So if my understanding is correct (don't bet on it, I mostly know classical physics), it is more like saying the graviton is the carrier on the quantum level for the gravatational waves.
    $endgroup$
    – JMac
    25 mins ago














13












13








13





$begingroup$

Both.



General relativity describes gravity as curvature of spacetime, and general relativity is an extremely successful theory. Its correct predictions about gravitational waves, as verified directly by LIGO, are especially severe tests.



Gravity also has to be quantum-mechanical, because all the other forces of nature are quantum-mechanical, and when you try to couple a classical (i.e., non-quantum-mechanical) system to a quantum-mechanical one, it doesn't work. See Carlip and Adelman for a discussion of this.



So we know that gravity has to be described both as curvature of spacetime and as the exchange of gravitons. That's not inherently a contradiction. We do similar things with the other forces. We just haven't been able to make it work for gravity.



Carlip, "Is Quantum Gravity Necessary?," http://arxiv.org/abs/0803.3456



Adelman, "The Necessity of Quantizing Gravity," http://arxiv.org/abs/1510.07195






share|cite|improve this answer









$endgroup$



Both.



General relativity describes gravity as curvature of spacetime, and general relativity is an extremely successful theory. Its correct predictions about gravitational waves, as verified directly by LIGO, are especially severe tests.



Gravity also has to be quantum-mechanical, because all the other forces of nature are quantum-mechanical, and when you try to couple a classical (i.e., non-quantum-mechanical) system to a quantum-mechanical one, it doesn't work. See Carlip and Adelman for a discussion of this.



So we know that gravity has to be described both as curvature of spacetime and as the exchange of gravitons. That's not inherently a contradiction. We do similar things with the other forces. We just haven't been able to make it work for gravity.



Carlip, "Is Quantum Gravity Necessary?," http://arxiv.org/abs/0803.3456



Adelman, "The Necessity of Quantizing Gravity," http://arxiv.org/abs/1510.07195







share|cite|improve this answer












share|cite|improve this answer



share|cite|improve this answer










answered 3 hours ago









Ben CrowellBen Crowell

51.6k6156303




51.6k6156303












  • $begingroup$
    Hey man, the links you sent are very useful and this really helped clear up certain misconceptions I had about gravity, so it can and in fact is very likely to be both. Thank you very much :-) !!
    $endgroup$
    – steve_just_steve
    2 hours ago






  • 3




    $begingroup$
    This is probably a naive question, but wouldn't gravitons also produce gravitational waves, since the other forces do, e.g. EM waves?
    $endgroup$
    – gardenhead
    51 mins ago










  • $begingroup$
    @gardenhead physics.stackexchange.com/questions/215173/… This suggests that gravitons are to gravitational waves as photons are to electromagnetic waves. So if my understanding is correct (don't bet on it, I mostly know classical physics), it is more like saying the graviton is the carrier on the quantum level for the gravatational waves.
    $endgroup$
    – JMac
    25 mins ago


















  • $begingroup$
    Hey man, the links you sent are very useful and this really helped clear up certain misconceptions I had about gravity, so it can and in fact is very likely to be both. Thank you very much :-) !!
    $endgroup$
    – steve_just_steve
    2 hours ago






  • 3




    $begingroup$
    This is probably a naive question, but wouldn't gravitons also produce gravitational waves, since the other forces do, e.g. EM waves?
    $endgroup$
    – gardenhead
    51 mins ago










  • $begingroup$
    @gardenhead physics.stackexchange.com/questions/215173/… This suggests that gravitons are to gravitational waves as photons are to electromagnetic waves. So if my understanding is correct (don't bet on it, I mostly know classical physics), it is more like saying the graviton is the carrier on the quantum level for the gravatational waves.
    $endgroup$
    – JMac
    25 mins ago
















$begingroup$
Hey man, the links you sent are very useful and this really helped clear up certain misconceptions I had about gravity, so it can and in fact is very likely to be both. Thank you very much :-) !!
$endgroup$
– steve_just_steve
2 hours ago




$begingroup$
Hey man, the links you sent are very useful and this really helped clear up certain misconceptions I had about gravity, so it can and in fact is very likely to be both. Thank you very much :-) !!
$endgroup$
– steve_just_steve
2 hours ago




3




3




$begingroup$
This is probably a naive question, but wouldn't gravitons also produce gravitational waves, since the other forces do, e.g. EM waves?
$endgroup$
– gardenhead
51 mins ago




$begingroup$
This is probably a naive question, but wouldn't gravitons also produce gravitational waves, since the other forces do, e.g. EM waves?
$endgroup$
– gardenhead
51 mins ago












$begingroup$
@gardenhead physics.stackexchange.com/questions/215173/… This suggests that gravitons are to gravitational waves as photons are to electromagnetic waves. So if my understanding is correct (don't bet on it, I mostly know classical physics), it is more like saying the graviton is the carrier on the quantum level for the gravatational waves.
$endgroup$
– JMac
25 mins ago




$begingroup$
@gardenhead physics.stackexchange.com/questions/215173/… This suggests that gravitons are to gravitational waves as photons are to electromagnetic waves. So if my understanding is correct (don't bet on it, I mostly know classical physics), it is more like saying the graviton is the carrier on the quantum level for the gravatational waves.
$endgroup$
– JMac
25 mins ago











1












$begingroup$

Gravity is as simple a force as all the others, which means that its simple when not looked at too closely, and far more sophisticated when it is. Given that it’s generally supposed all forces are merely low energy relics of a single high energy one, we might suppose that all the forces are as complicated as each other when looked at closely.



Popularly, Gravity is seen as different from the other forces in that its geometric. It turns out that the other forces are also geometric. Nevertheless, the main difference is that in gravity, the metric tensor, which tells us how to measure distances, times and angles is directly implicated in a way that it isn’t in the other forces. For example, there are two equations in EM, one of which does not involve the metric and hence seen as topological, and the other, which does (via the Hodge star) and hence, is coupled with gravity. The other two forces, the weak and strong force are modelled as gauge theories of the Yang-Mills type and hence directly generalising the EM equations. So similarly, they also have a topological and metric aspect, and the latter means it couples to gravity.



Now, whilst gravity hasn’t yet been quantised with several ongoing major projects that attempt this there are several partial semi-classical results which are used to help orientate research into this. One such result is that the quanta of gravity, the graviton, is a massless spin-2 particle. This is understood by looking at a linearisation of gravity which is used in the theory of gravitational radiation, and then by quantising this to show we have a massless spin-2 particle, aka the graviton.






share|cite|improve this answer









$endgroup$













  • $begingroup$
    Thank you very much for your answer! Linearisation of gravity is definitely something to look into for me :-)!
    $endgroup$
    – steve_just_steve
    48 mins ago
















1












$begingroup$

Gravity is as simple a force as all the others, which means that its simple when not looked at too closely, and far more sophisticated when it is. Given that it’s generally supposed all forces are merely low energy relics of a single high energy one, we might suppose that all the forces are as complicated as each other when looked at closely.



Popularly, Gravity is seen as different from the other forces in that its geometric. It turns out that the other forces are also geometric. Nevertheless, the main difference is that in gravity, the metric tensor, which tells us how to measure distances, times and angles is directly implicated in a way that it isn’t in the other forces. For example, there are two equations in EM, one of which does not involve the metric and hence seen as topological, and the other, which does (via the Hodge star) and hence, is coupled with gravity. The other two forces, the weak and strong force are modelled as gauge theories of the Yang-Mills type and hence directly generalising the EM equations. So similarly, they also have a topological and metric aspect, and the latter means it couples to gravity.



Now, whilst gravity hasn’t yet been quantised with several ongoing major projects that attempt this there are several partial semi-classical results which are used to help orientate research into this. One such result is that the quanta of gravity, the graviton, is a massless spin-2 particle. This is understood by looking at a linearisation of gravity which is used in the theory of gravitational radiation, and then by quantising this to show we have a massless spin-2 particle, aka the graviton.






share|cite|improve this answer









$endgroup$













  • $begingroup$
    Thank you very much for your answer! Linearisation of gravity is definitely something to look into for me :-)!
    $endgroup$
    – steve_just_steve
    48 mins ago














1












1








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Gravity is as simple a force as all the others, which means that its simple when not looked at too closely, and far more sophisticated when it is. Given that it’s generally supposed all forces are merely low energy relics of a single high energy one, we might suppose that all the forces are as complicated as each other when looked at closely.



Popularly, Gravity is seen as different from the other forces in that its geometric. It turns out that the other forces are also geometric. Nevertheless, the main difference is that in gravity, the metric tensor, which tells us how to measure distances, times and angles is directly implicated in a way that it isn’t in the other forces. For example, there are two equations in EM, one of which does not involve the metric and hence seen as topological, and the other, which does (via the Hodge star) and hence, is coupled with gravity. The other two forces, the weak and strong force are modelled as gauge theories of the Yang-Mills type and hence directly generalising the EM equations. So similarly, they also have a topological and metric aspect, and the latter means it couples to gravity.



Now, whilst gravity hasn’t yet been quantised with several ongoing major projects that attempt this there are several partial semi-classical results which are used to help orientate research into this. One such result is that the quanta of gravity, the graviton, is a massless spin-2 particle. This is understood by looking at a linearisation of gravity which is used in the theory of gravitational radiation, and then by quantising this to show we have a massless spin-2 particle, aka the graviton.






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Gravity is as simple a force as all the others, which means that its simple when not looked at too closely, and far more sophisticated when it is. Given that it’s generally supposed all forces are merely low energy relics of a single high energy one, we might suppose that all the forces are as complicated as each other when looked at closely.



Popularly, Gravity is seen as different from the other forces in that its geometric. It turns out that the other forces are also geometric. Nevertheless, the main difference is that in gravity, the metric tensor, which tells us how to measure distances, times and angles is directly implicated in a way that it isn’t in the other forces. For example, there are two equations in EM, one of which does not involve the metric and hence seen as topological, and the other, which does (via the Hodge star) and hence, is coupled with gravity. The other two forces, the weak and strong force are modelled as gauge theories of the Yang-Mills type and hence directly generalising the EM equations. So similarly, they also have a topological and metric aspect, and the latter means it couples to gravity.



Now, whilst gravity hasn’t yet been quantised with several ongoing major projects that attempt this there are several partial semi-classical results which are used to help orientate research into this. One such result is that the quanta of gravity, the graviton, is a massless spin-2 particle. This is understood by looking at a linearisation of gravity which is used in the theory of gravitational radiation, and then by quantising this to show we have a massless spin-2 particle, aka the graviton.







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answered 54 mins ago









Mozibur UllahMozibur Ullah

4,94432252




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  • $begingroup$
    Thank you very much for your answer! Linearisation of gravity is definitely something to look into for me :-)!
    $endgroup$
    – steve_just_steve
    48 mins ago


















  • $begingroup$
    Thank you very much for your answer! Linearisation of gravity is definitely something to look into for me :-)!
    $endgroup$
    – steve_just_steve
    48 mins ago
















$begingroup$
Thank you very much for your answer! Linearisation of gravity is definitely something to look into for me :-)!
$endgroup$
– steve_just_steve
48 mins ago




$begingroup$
Thank you very much for your answer! Linearisation of gravity is definitely something to look into for me :-)!
$endgroup$
– steve_just_steve
48 mins ago










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