At 15:05 I could not understand why you assumed del_(i) j^i to be zero. I suppose you assumed it to be zero just to make sure that Q dot is zero. If that is the case we can't prove a formula looking at the equation to be proved and making assumption accordingly. Sir could you please help me with this?
Same question. Maybe it is because j^i is zero when |x| goes to infinity (Noether lemma). After integrating we have j^i times the integral, and if j^i is zero then whole construction is zero.
That integral in red is the volume integral of the divergence of j^i over all space. Due to the divergence theorem, this equals the integral of j^i over the boundary. This boundary is at infinity. We know that j^i vanishes at infinity, so the new integral will be zero.
From the line at the top: " T^mu_nu =..." All the mu indices are up, the nu indices are down. If we raise all the nu indices, we get the equation he writes at the bottom, just in an integral.
Do you have any videos showing that the energy momentum tensor is conserved? I am having trouble proving this. Always end up with two terms that almost cancel but not quite...
well, that's the thing about these sorts of discoveries. it just takes one person coming up with them and then the rest of the world has a path to follow.
I got 98 marks out of 100 in Particle physics paper, all credit goes to you Sir, I really appreciate your work!
Congratulations! Glad I could help!
Love what you're doing! May you be bestowed with abundant grace, wisdom and bliss✨
At 15:05 I could not understand why you assumed del_(i) j^i to be zero. I suppose you assumed it to be zero just to make sure that Q dot is zero. If that is the case we can't prove a formula looking at the equation to be proved and making assumption accordingly. Sir could you please help me with this?
Same question. Maybe it is because j^i is zero when |x| goes to infinity (Noether lemma). After integrating we have j^i times the integral, and if j^i is zero then whole construction is zero.
But I am not sure
That integral in red is the volume integral of the divergence of j^i over all space. Due to the divergence theorem, this equals the integral of j^i over the boundary. This boundary is at infinity. We know that j^i vanishes at infinity, so the new integral will be zero.
How did you raised the suffex of mu on 25:12
From the line at the top: " T^mu_nu =..."
All the mu indices are up, the nu indices are down. If we raise all the nu indices, we get the equation he writes at the bottom, just in an integral.
Do you have any videos showing that the energy momentum tensor is conserved? I am having trouble proving this. Always end up with two terms that almost cancel but not quite...
the delta phi wasn't really explained when using the derive instead
Hola. Me podrías dar algunas referencias bibliográficas para encontrar ese contenido? Desde ya muchas gracias.
Lectures in QFT Ashok Das y Peskin Schroeder intro to QFT es lo que uso además de mis apuntes
great
Macher
TYPICAL QFT-VIDEO: ONLY MATH, NO PHYSICS. ACCEPT THAT NOETHER'S THEOREM IS CORRECT AND DO SOMETHING WITH IT.
How do people come up with this shit
By thinking in 4D space time 😂
well, that's the thing about these sorts of discoveries. it just takes one person coming up with them and then the rest of the world has a path to follow.