Transformation Definition and 1000 Threads

  1. A

    Find the Reflection Line of a Matrix, and Analyze the Transformation

    I just want to make sure I'm doing this right. I know how to do the rotation, but reflection isn't demonstrated in the text. From what I'm seeing in the book, it seems like you take the matrix and simply multiply it by ##\begin{bmatrix} x \\ y \end{bmatrix} ## Assuming that's the case, I get...
  2. binbagsss

    A Schrodinger equation/Madelung equation phase transformation

    When one does the phase transformation ##\psi(\vec{x},t)=R(\vec{x},t)\exp^{iS(\vec{x},t)/\bar{h}}## For this transformation to be valid doesn't it need to have the same asymptotic behaviour ##x \to \pm \infty##, and also at ##x=0 ## as the original wave-function ##\psi## does? How come this is...
  3. M

    How should I show that the transformation makes the system Hamiltonian?

    Proof: Consider the transformation ## x=\frac{1}{\sqrt{1+e^{-2q}}} ## and ## y=\frac{1}{\sqrt{1+e^{-2p}}} ## with the Hamiltonian function ## H(q, p)=ap-b\cdot ln(e^{p}+\sqrt{1+e^{2p}})+cq-d\cdot ln(e^{q}+\sqrt{1+e^{2q}}) ##. Let ## \dot{x}=\frac{dx}{dt}=(a-by)x(1-x^2)=(a-by)(x-x^3) ## and ##...
  4. A

    Lorentz Transformation For Moving Particles

    So, I linked an image to Problem 1.26 below. As far as that problem, to save you the trouble, the answers (at least from what I have) are: a) ##\gamma = 1.7 ## b) ## t = 3x10^{-8} ## c) ## Pions = 30,555 ## d) ## Pions = 29,628 ## Fairly confident those are correct, but now this question...
  5. K

    I A question about Curved Spaces: Gauss and Riemann (Einstein Gravity in a Nutshell by Zee)

    In p. 84, Zee says “In the new coordinates, M is replaced by M’ = R[-1]MR.” However, I figure out M is replaced by M’ = RMR[-1]. Why is M replaced by M’ = R[-1]MR?
  6. P

    I Noethers theorem, transformations of the Lagrange density

    I'm so confused here. If we make the transformation of the coordinates x -> x', are we not suppose to consider the transformation of the coordinates only $$ \phi(x) \rightarrow \phi(x') $$ ? Then why are they writing $$ \phi(x) \rightarrow \phi'(x') $$ ? If $$ \phi(x) $$ is a scalar function...
  7. chwala

    I Understanding the given transformation - PDE

    My interest is on how they arrived at ##r^2 \sin θ## My approach using the third line, is as follows ##\cos θ[r^2 \cos θ \sin θ \cos^2 ∅ + r^2 \sin θ \cos θ cos^2∅ ] + r\sin θ [r\sin^2 θ \cos^2∅ + r \sin^2 θ \sin^2 ∅]=## ##\cos θ[r^2 \cos θ \sin θ[\cos^2 ∅+ \sin^2 ∅]] + r\sin θ [r\sin^2 θ...
  8. I

    MCNPX Transformation

    Hello, I doing my thesis, I'm beginner in MCNPX. I want to ask about transformation in MCNPX, I want to transform this head phantom in inside and outside field ( radiation using LINAC from face to ear) in angle 90° and 270 °. Can anyone help me to solve this problem with transformation code?
  9. M

    B Origins of the no-cloning theorem

    I was watching this video by minutephysics on the No-cloning theorem. Henry very plainly shows why the no-cloning theorem holds, given the setup. However, I am no quantum physicist and lack the necessary background to truly understand what's going on there. What are the origins of the 3...
  10. wirefree

    I Is there a way to calculate this transformation?

    Namaste & G'day! Imagine a helicopter view of a Polo ground. It's length & breadth are known. Now you are seated where the blue dot is. Your view is such: How do mathematicians calculate the distance travelled by a ball from the second perspective? From the top view, this would be...
  11. H

    A Vector field vs. four scalar fields ("QFT and the SM", Schwartz)

    This is the statement in question: But if they were scalar fields, they would not transform at all. How could they contribute differently if they didn't change?
  12. C

    What Happens to Blue Sphere Silica Gel at High Temperatures?

    What type of chemical and physical transformation occurs in the blue sphere silica gel when it is subjected to very high temperatures above the temperature supported by it for several minutes? does it turn into a compound that will absorb and store moisture and water inside and can leak if it...
  13. L

    I Help Understanding Equation 3.6 in Covariant Physics by Moataz H. Emam

    I am a physics enthusiast reading Covariant Physics by Moataz H. Emam. In his chapter about Point Particle mechanics there is a transformation equation for a displacement vector. I don't see how he arrived at the final equation 3.6. Is it a chain rule or product rule? Can't seem to figure it...
  14. S

    I Fuel paradox arising from Galilean transformation?

    I have encountered a problem related to the Galilean Transformation. Let's consider two observers who will be referred to as ##O## and ##O^{'}##, with their corresponding coordinates ##(t,x,y,z)## and ##(t^{′},x^{′},y^{′},z^{'})## respectively. They are initially at the same location, at time...
  15. Baela

    A Infinitesimal Coordinate Transformation and Lie Derivative

    I need to prove that under an infinitesimal coordinate transformation ##x^{'\mu}=x^\mu-\xi^\mu(x)##, the variation of a vector ##U^\mu(x)## is $$\delta U^\mu(x)=U^{'\mu}(x)-U^\mu(x)=\mathcal{L}_\xi U^\mu$$ where ##\mathcal{L}_\xi U^\mu## is the Lie derivative of ##U^\mu## wrt the vector...
  16. milkism

    Field transformations in the z-direction

    Question: Eq. 12.109: My solution: We’ll first use the configuration from figure 12.35 in the book Griffiths. Where the only difference is that v_0 is in the z-direction. The electric field in the y-direction will be the same. $$E_y = \frac{\sigma}{\epsilon _0}$$ Now we're going to derive the...
  17. O

    Coordinate transformation into a standard flat metric

    I started by expanding ##dx## and ##dt## using chain rule: $$dt = \frac{dt}{dX}dX+\frac{dt}{dT}dT$$ $$dx = \frac{dx}{dX}dX+\frac{dx}{dT}dT$$ and then expressing ##ds^2## as such: $$ds^2 =...
  18. G

    I 4-Current vector potential transformation under Gauge fixing

    I am given an initial vector potential let's say: \begin{equation} \vec{A} = \begin{pmatrix} g(t,x)\\ 0\\ 0\\ g(t,x)\\ \end{pmatrix} \end{equation} And I would like to know how it will transform under the Lorenz Gauge transformation. I know that the Lorenz Gauge satisfy...
  19. Vanilla Gorilla

    B Transformation Rules For A General Tensor M

    So, I've been watching eigenchris's video series "Tensors for Beginners" on YouTube. I am currently on video 14. I am a complete beginner and just want some clarification on if I'm truly understanding the material. Basically, is everything below this correct? In summary of the derivation of the...
  20. G

    Apply the Legendre Transformation to the Entropy S as a function of E

    Hi, Unfortunately I am not getting anywhere with task three, I don't know exactly what to show Shall I now show that from ##S(T,V,N)## using Legendre I then get ##S(E,V,N)## and thus obtain the Sackur-Tetrode equation?
  21. L

    Point transformation for a constrained particle

    Hi, unfortunately, I'm not that fit concerning the Lagrangian formalism, so I'm not sure if I solved the problem 1a correctly. I have now proceeded as follows the Lagrangian is $$L=T-U$$ Since there are no constraining or other forces acting on the point mass, I assume that the...
  22. J

    Transformation Matrix T in Terms of β1, β2 with Row Reduction Explained

    T(α1), T(α2), T(α3) written in terms of β1, β2: Tα1 =(1,−3) Tα2 =(2,1) Tα3 =(1,0). Then there is row reduction: Therefore, the matrix of T relative to the pair B, B' is I don't understand why the row reduction takes place? Also, how do these steps relate to ## B = S^{-1}AS ##? Thank you.
  23. Ahmed1029

    I Is this transformation irreversible?

    This is a cyclic transformation. Is it safe to say thay it's irreversible because if you reverse it, it means I could extract an amount of heat from a cold reservoir and move it into a hotter reservoir with no other effect?
  24. luqman

    Coordinate Transformation (multivariable calculus)

    My Progress: I tried to perform the coordinate transformation by considering a general function ##f(\mathbf{k},\omega,\mathbf{R},T)## and see how its derivatives with respect all variable ##(\mathbf{k},\omega,\mathbf{R},T)## change: $$ \frac{\partial}{\partial\omega} f =...
  25. negarina

    Can a single-phase solid solution have a martensitic transformation?

    I'm trying to investigate the possibility of martensitic transformation in a non-iron alloy, described as a single-phase alpha-solid-solution (Nickel-Silver CuNi12Zn25Pb1, CW404J). I know that Cu-Ni-Zn alloys with higher zinc amounts show even shape memory effects. And that CuNi12Zn25Pb1 is no...
  26. J

    Linear Transformation from R3 to R3

    "There is a linear transformation T from R3 to R3 such that T (1, 0, 0) = (1,0,−1), T(0,1,0) = (1,0,−1) and T(0,0,1) = (1,2,2)" - why is this the case? Thank you.
  27. G

    I Coordinate System Transformation: Lowering/Raising Indices Explained

    In《Introducing Einstein's Relativity Ed 2》on page 106"lowering the first index with the metric,then it is easy to establish,for example by using geodesic coordinates..." In 《A First Course in General Relativity - 2nd Edition》on page 159 "If we lower the index a,we get(in the locally flat...
  28. BadgerBadger92

    I Difference Between Lorentz Transformation & Special Relativity

    Sorry for the extra question. Just have a lot of questions lately and I know some people around here are annoyed with that.
  29. S

    Simple Fourier transformation calculation

    So, ##\hat{p}(\omega)=\int_{-\infty}^{\infty} p(t)e^{-i\omega t}\mathrm{d}t=A\int_{0}^{\infty}e^{-t(\gamma+i(\omega+\omega_0))}=A\left[-\frac{e^{-t(\gamma+i(\omega+\omega_0))}}{\gamma+i(\omega+\omega_0)}\right]_0^\infty,## provided ##\gamma+ i(\omega+\omega_0)\neq 0## for the last equality. Now...
  30. S

    B Lorentz Transformation of Electric & Magnetic Fields Visualized

    I made a tool for calculating and visualizing how the electric and magnetic fields transform under a Lorentz boost. Thought I'd share it here, in case anyone finds it interesting. https://em-transforms.vercel.app/
  31. SaintRodriguez

    I Legendre Transformation & Hamilton-Jacobi Formalism: A Relationship?

    Hey I have a question about the relation between Legendre transformation and Hamilton-Jacobi formalism. Is there some relation? Cause Hamilton-Jacobi is the expression of Hamiltonian with a transformation.
  32. P

    I Question about algebraic transformation

    Hello, I would like to reproduce the following equation, but I don't quite understand how to do the transformation: $$ \sum_{i=1}^k \left( \frac{\langle y , x_i^* \rangle}{\sqrt{\langle x_i^*, x_i^* \rangle}} \right)^2 = \langle y, y \rangle$$ Where ##x_1^*,...,x_k^*##, are orthogonalized...
  33. Sciencemaster

    I Coord Transform in de Sitter Space: Phys Significance &Linearity?

    Could one derive a set of coordinate transformations that transforms events between different reference frames in the de Sitter metric using the invariant line element, similar to how the Lorentz Transformations leave the line element of the Minkowski metric invariant? Would these coordinate...
  34. DuckAmuck

    A Non-unitary gauge transformation

    You see in the literature that the vector potentials in a gauge covariant derivative transform like: A_\mu \rightarrow T A_\mu T^{-1} + i(\partial_\mu T) T^{-1} Where T is not necessarily unitary. (In the case that it is ##T^{-1} = T^\dagger##) My question is then if T is not unitary, how is...
  35. QuarkDecay

    Fourier transformation for circular apertures

    My notes say that the Resolution of the Aperture(in the Electric field of the wave) is the Fourier transformation of the aperture. Then gives us the equation of the aperture: and says that for the circular aperture in particular also: My attempt at solving this: We know that the Fourier...
  36. alhuebel

    I Constraints on Lorentz Velocity Transformation

    1. The 2nd line on the 3rd page of your notes, you have x=ct and x'=ct', thus ux=dx/dt and ux'= dx'/dt' =c according to Einstein's assumptiuon. 2. But near the end of the last page, you wrote dx'/dt' = (ux -v)/(1-vux/c2) . Compare with 1. This equation can be valid only for ux=c and...
  37. A

    A What assumptions underly the Lorentz transformation?

    The Lorentz transform for velocities is as follows: $$u=\frac{v+w}{1+\frac{vw}{c^{2}}}$$ But which assumption exactly underlies this so that you get exactly this formula and not any other formula with approximately the same properties?
  38. P

    MHB Invariance of Asymmetry under Orthogonal Transformation

    Show that the property of asymmetry is invariant under orthogonal similarity transformation
  39. LCSphysicist

    Time dependent canonical transformation

    THe question is pretty simple. I was doing an exercise, in which $$p = \lambda P, Q = \lambda q$$ is a canonical transformation. We can check it by $$\{Q,P \} = 1$$ But, if we add $$t' = \lambda ^2 t$$, the question says that the transformation is not canonical anymore. I am a little...
  40. A

    I Transformation of connection coefficients

    I don't understand why the highlighted term is there. This image was taken from Sean Carroll's notes available here: preposterousuniverse.com/wp-content/uploads/grnotes-three.pdf
  41. wnvl2

    I Applying Reisenbach Transf. to EM Wave in Microwave Oven

    There is no possible measurement, no matter how clever, that can measure the one way speed of light. It is a synchronization convention. In this topic I would like to apply this idea on a specific case. I have a microwave oven with width L. In this oven I have a standing wave. $$E(t,x)=E...
  42. LCSphysicist

    Energy change under point transformation

    How do the energy and generalized momenta change under the following coordinate transformation $$q= f(Q,t)$$The generalized momenta: $$P = \partial L / \partial \dot Q = \partial L / \partial \dot q\times \partial \dot q / \partial \dot Q = p \partial \dot q / \partial \dot Q = p \partial q /...
  43. Zeeshan Ahmad

    Understanding Velocity Transformation

    I have used velocity transformation ibut a little confused on it so do solve the problem
  44. H

    Sifting property of a Dirac delta inverse Mellin transformation

    Hi, I have to verify the sifting property of ##\frac{1}{2\pi i} \int_{-i\infty}^{i\infty} e^{-sa}e^{st} ds## which is the inverse Mellin transformation of the Dirac delta function ##f(t) = \delta(t-a) ##. let ##s = iw## and ##ds = idw## ##\frac{1}{2\pi} \int_{-\infty}^{\infty} e^{-iwa}e^{iwt}...
  45. Samama Fahim

    I Deriving Lorentz Transformations: Hyperbolic Functions

    While deriving Lorentz transformation equations, my professor assumes the following: As ##\beta \rightarrow 1,## $$-c^2t^2 + x^2 = k$$ approaches 0. That is, ##-c^2t^2 + x^2 = 0.## But the equation of the hyperbola is preserved in all inertial frames of reference. Why would ##-c^2t^2 + x^2##...
  46. A

    A Finding the Hermitian generator of a Symplectic transformation

    Consider a set of ##n## position operators and ##n## momentum operator such that $$\left[q_{i},p_{j}\right]=i\delta_{ij}.$$ Lets now perform a linear symplectic transformation $$q'_{i} =A_{ij}q_{j}+B_{ij}p_{j},$$ $$p'_{i} =C_{ij}q_{j}+D_{ij}p_{j}.$$ such that the canonical commutation...
  47. platypi

    Computing the infinitesimal generators for the Mobius transformation

    I don't know where to start. I understand that the constraint ##ad-bc=1## gives us one less parameter since ##d=1+bc/a##. So we can rewrite our original function. I know how to compute the generators of matrix groups but in this case the generators will be functions. I also know there should be...
  48. C

    A Understand Polaron Transformation in Quantum Optics: Wilson-Rae, Imamoğlu

    I'm trying to understand the so-called polaron transformation as frequently encountered in quantum optics. Take the following paper as example: "Quantum dot cavity-QED in the presence of strong electron-phonon interactions" by I. Wilson-Rae and A. Imamoğlu. We have the spin-phonon model with...
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