An effective view on quantum gravity! | with John Donoghue

A common issue that arise when attempting to quantize gravity is the incompatibilty between quantum field theory and general relativity. However, they work fine at ordinary energy scales. This suggests a separation between low- and high-energy descriptions, the latter requiring a full-fledged quantum theory of gravity. However, at low-energy scales a description in terms of effective field theory may just be enough. In this way, we can distinguish low-energy effects and obtain some insights for the high-energy regime. In this video, John Donoghue explains how effective field theory can indeed help us to obtain an efficient understanding of quantum gravity.
John F. Donoghue is an American theoretical physicist. He works on several topics in high-energy physics, such as particle physics, astrophysics, and cosmology. He dedicated much effort to a description of quantum gravitational physics in terms of an effective field theory. Presently, he is an Emeritus Professors at the University of Massachusetts, USA.

[@vanikaghajanyan7760]

39:00 Maybe GR was QG…
“The geometry of space in general relativity theory turned out to be another field, therefore the geometry of space in GR is almost the same as the gravitational field.” (Smolin).
However apparently, the gravitational field is space-time in the Planck system: F(G)/F(e)=Gm(pl)^2/e^2=1/α, that is, gravity~strong interaction*.
This assumption follows from the Schwarzschild solution: the gravitational radius (or Schwarzschild radius) is a characteristic radius defined for any physical body with mass: r(G)=2GM/c^2.
Consequently: 2E(0)/r(G)=F(pl)=c^4/G=ε(pl)/r(pl): with indicating the mutual quantization of the mass (energy) and space-time: m(0)/m(pl)=r(G)/2r(pl)=n, where n-total number of quanta of the system; the tension vector flux: n=[(1/4π)(Gћc)^-1/2]gS ( const for all orbits of the system: n=0,1,2,3....).
Moreover, the parameter r(0)=r(G)-r(pl)=(2n-1)r(pl): defining the interval of the formation of the system, at n=0, when r=r(G)=0 (for example, the state of the "universe" before the Big Bang) turns out to be a quite definite quantity: r(0)=-r(pl).
In the area [(-rpl) - 0 - (+rpl)] there is an implementation of external forces, "distance": (-rpl)+(+rpl)=0 (≠2rpl).
That is, the frightening "true singularity" is actually a superconducting heterotrophic window between the proto-universe (the source) and physical bodies**.
P.S.
As a fundamental theory, GR has the ability with just one parameter: r(G)/r=k to predict, explain new physical effects, and amend already known ones.
Photon frequency shift in gravitational field Δw/w(0)=k; the angle of deflection of a photon from a rectilinear propagation path =2k, the Newtonian orbit of the planet shifts forward in its plane: during one revolution, a certain point of the orbit is shifted by an angle =3πk, for a circular orbit (eccentricity е=0); in the case of an elliptical orbit - for example, for perihelion displacement, the last expression must be divided by (1-е^2).
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*) - GR predicts a new physical effect: w/w(pl)=k; expression for gravitational radiation from a test body.
This is amenable to physical examination in laboratory conditions at present.
**) - From this, generally, from Einstein's equations, where the constant c^4/G=F(pl), one can obtain a quantum expression (as vibration field) for the gravitational potential: ф(G)=(-1/2)[Għ/с]^1/2(w) = -[h/4πm(pl)]w.
Final formula:ф(G)=-(w/wpl)c^2/2, where ф(G) - is Newtonian gravitational potential, r(n')=nλ/π=(n+n')2r(pl), the corresponding orbital radius, w - the frequency of the quanta of the gravitational field (space-time); - obviously, the quanta of the field are themselves quantized: λ=(1+n'/n)λpl = 2πc/w, where n'/n - system gravity unpacking ratio, n'- the orbit number (n'=0,1,2,3…).
Accordingly, m=m(pl)/(1+n'/n), where m=ħw/c^2 : is the quantum of the full mass: M=n'm [

[@FobbitMike]

Sound quality is awful.