Linked Questions

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1answer
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We Don't NEED Quantum Gravity because Gravity isn't Even A Force! [duplicate]

Now, I understand the motivation for quantum gravity. I honestly want to work on a theory myself. However, gravity, according to General Relativity, is not a fundamental force of nature. To me, it's ...
10
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2answers
861 views

Why does gravity need a graviton? [duplicate]

Einstein theorized that gravity is a phenomena manifested by the curvature of spacetime, in effect it IS the curvature of spacetime. If this is so, why do we need a graviton to convey the force of ...
2
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1answer
474 views

Why are gravitons needed to explain gravitational attraction in quantum gravity? [duplicate]

I've read and heard multiple times that gravity can't be explained by the current understandings of quantum physics. Wikipedia's Gravity entry briefly explains the incompatibility between general ...
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1answer
239 views

If gravity arises from the curvature of spacetime, why is there a need for gravitons? [duplicate]

If gravity arises from the curvature of space time, why is there a need for gravitons? If someone could explain this to me I would be very thankful. I dont understand why.
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1answer
107 views

What if quantum mechanics and general relativity are not connected? [duplicate]

The main objective in modern physics research is to find a way to unify quantum mechanics and general relativity thorugh a series of theoretical approaches called "quantum gravity theories" But what ...
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0answers
96 views

Gravity and graviton [duplicate]

If gravity is merely a consequence of massive bodies and the curvature of spacetime, why do we believe a graviton should exist in order to transmit gravitational forces.
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0answers
93 views

Does the existence of graviton contradict gravity being spacetime curvature? [duplicate]

Is gravity a property-curvature of space-time it's self as descriped in GR? Or the notion of 'graviton' is necessary in order to embed the 'classical GR theory' to the quantum's mechanics 'world' ...
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0answers
61 views

What´s the physical foundation of the assumption that the curvature of spacetime can be quantised? [duplicate]

At the moment different paths (by percentual very few people in the world) are taken to arrive (that is, if an arrival exists) at a theory that can quantise the curvature of spacetime. Considering the ...
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0answers
55 views

Why should we want to quantize Gravity? [duplicate]

I understand that it will be "nice" to have a quantum description of Gravity as well, just like the other 3 forces. I would like to find out what problems arise in existing theory (not counting String ...
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0answers
54 views

Unified theory of gravity [duplicate]

I have heard that a lot of times, but I have never completely understood what is a force theory unified with quantum mechanics, and also, why do we need this kind of gravitational theory to fully ...
3
votes
0answers
48 views

Does the universe need Quantum Gravity? [duplicate]

A lot of supporters of string theory say that it has to be right because the quantum gravity is necessary for the universe, is this true? Does the universe need quantum gravity?
1
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0answers
38 views

Quantum gravity: How do we know gravity operates at quantum scales? [duplicate]

Edit: An alternate angle on the original question I asked below: Would general relativity still create singularities in special cases (center of black holes) if we assumed that gravity had a lower ...
32
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5answers
3k views

Is the graviton hypothetical?

Wikipedia lists the graviton as a hypothetical particle. I wonder whether graviton is indeed hypothetical or does its existence directly follow from modern physics? Does observation of gravitational ...
32
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4answers
11k views

Why is gravity so hard to unify with the other 3 fundamental forces?

Electricity and magnetism was unified in the 19th century, and unification of electromagnetism with the weak force followed suit, bringing into play the electroweak force. I've been told that ...
26
votes
5answers
3k views

Is the quantization of gravity necessary for a quantum theory of gravity?

The other day in my string theory class, I asked the professor why we wanted to quantize gravity, in the sense that we want to treat the metric on space-time as a quantum field, as opposed to, for ...

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