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TheHeraclitus

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- How are particles described in loop quantum gravity?

I am reading a popular-science book

He writes:

So basically, space (spacetime) is just another quantum field like all the others, and the quanta of this field is the nod. Nods have volume, which means they must be extended in dimensions, they must have shape. But all quanta of the other fields, for example photon, electron, quark are described as point particles, they have no volume. It seems absurd to me that every quantum field has point particles except gravitational field which has extended particles.

Rovelli also claims there is minimum length in nature, but point particles would be smaller, they are dimensionless.

So, how does Rovelli and Loop quantum gravity deal with these particles?

*Reality Is Not What It Seems*by Carlo Rovelli, one of the founders of loop quantum gravity.He writes:

andThe nodes of the graph represent the discrete packets of volume and, as in the case of photons, can only have certain sizes, which can be computed using Dirac's general quantum equation. Every nodenin the graph has its own volumevn:one of the numbers in the spectrum of the volume.

andThe nodes are the elementary quanta of which physical space is made. Every node of the graph is a "quantum particle of space".

the gravitational field is space. Space is no longer different from matter. It is one of the "material" components of the world, akin to the electromagnetic field. It is a real entity which undulates, fluctuates, bends and contorts.

So basically, space (spacetime) is just another quantum field like all the others, and the quanta of this field is the nod. Nods have volume, which means they must be extended in dimensions, they must have shape. But all quanta of the other fields, for example photon, electron, quark are described as point particles, they have no volume. It seems absurd to me that every quantum field has point particles except gravitational field which has extended particles.

Rovelli also claims there is minimum length in nature, but point particles would be smaller, they are dimensionless.

So, how does Rovelli and Loop quantum gravity deal with these particles?