Recent content by Daniel_C
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Calculating Divergent Amplitude in Phi-4 Theory
For the diagram In scalar field theory, I have obtained an integral which looks like $$\int_{0}^{\Lambda} \frac{d^4 q}{(2\pi)^4} \frac{i}{q^2 - m^2 + i\varepsilon} \frac{i}{(p - q)^2 - m^2 + i\varepsilon}$$ I am required to calculate this and obtain the divergent amplitude $$i\mathcal{M} =...- Daniel_C
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- Amplitude Divergent Feynman rules Integration Quantum field theory Theory
- Replies: 1
- Forum: Advanced Physics Homework Help
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QFT for Gifted Amateur - Problem 2.2
I'm getting confused by the perturbation theory aspect of problem 2.2 in this book. We have to show that the energy eigenvalues are given by $$E_n = \left(n + \frac{1}{2}\right) \hbar \omega + \frac{3\lambda}{4} \left(\frac{\hbar}{m\omega}\right)^2 (2n^2 + 2n + 1)$$ For the Hamiltonian...- Daniel_C
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- Amateur Perturbation theory Qft Quantum harmonic oscillator Quantum mechanics
- Replies: 1
- Forum: Advanced Physics Homework Help
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Undergrad Why does a Lagrangian matter for the standard model?
Hi, I don't know much about the standard model but I'm asking out of interest. Why do we actually need a Lagrangian for the standard model? Surely when you apply the relevant Euler-Lagrange equations, you end up with a variety of equations like the Maxwell equations or Dirac equations. Why...- Daniel_C
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- Lagrangian Lagrangian density Matter Model Standard Standard model
- Replies: 3
- Forum: High Energy, Nuclear, Particle Physics
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Undergrad Deriving tensor transformation laws
Thanks so much for the quick reply!- Daniel_C
- Post #3
- Forum: Special and General Relativity
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Undergrad Deriving tensor transformation laws
Hi, I'm worried I've got a grave misunderstanding. Also, throughout this post, a prime mark (') will indicate the transformed versions of my tensor, coordinates, etc. I'm going to define a tensor. $$T^\mu_\nu \partial_\mu \otimes dx^\nu$$ Now I'd like to investigate how the tensor transforms...- Daniel_C
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- Basis vectors deriving General relativity Laws Tensor Transformation
- Replies: 3
- Forum: Special and General Relativity
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What are Tensors and How Do They Relate to Scientific Research?
Hi, I'm interested in tensors. That's all. I think.- Daniel_C
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- Replies: 1
- Forum: New Member Introductions