Skip to main content

All Questions

Filter by
Sorted by
Tagged with
2 votes
1 answer
168 views

Transformation of wavefunction

While learning QM, I was wondering how would the wavefunction of a particle, suppose charged particle, look for different observers moving with respect to each other. To begin with, let the electric ...
Users's user avatar
  • 457
1 vote
0 answers
90 views

Galilean invariance of Burgers Equation [closed]

I think the following statement is true: if $u$ solves the burgers equation (ie $u$ solves $$\frac{\partial u}{\partial t} + u\frac{\partial u}{\partial x} = 0$$ then so does $$u^c = u(x-ct,t)+c.$$ I'...
yoshi's user avatar
  • 123
0 votes
0 answers
88 views

How can I show that the one-dimensional wave equation (with a constant propagation velocity $c$) is not invariant under Galilean transformation? [duplicate]

The one-dimensional wave equation is given by
Sriya's user avatar
  • 1
3 votes
3 answers
535 views

Velocity and kinetic energy, violating galilean relativity

I have a toy car and a battery. The barrery has a screen that shows how much energy it has left. Since kinetic energy is proportional to velocity squared, I need 1J of energy to go from 0m/s=>1m/s, ...
Matt's user avatar
  • 84
2 votes
1 answer
134 views

Time evolution of Galilean boost

I was introduced the generator of Galilean boost $K=mx-pt$. I was given an Hamiltonian with several particles: $H=\sum_i \frac{p_i^2}{2m_i}+V(|x_i-x_j|)$ where the potential only depends on the ...
Matt's user avatar
  • 197
2 votes
0 answers
128 views

Invariance of the Schoedinger equation for the Galilean transformation [closed]

Show that the schroedinger e is covariant under the galilean transformation : $\overrightarrow{r'}=\overrightarrow{r}-\overrightarrow{V}t$ iff the wave fucntion transforms like: $$\psi^\prime=e^{\left(...
Acephalus's user avatar
  • 189
1 vote
1 answer
800 views

Galilean transformation of the wave equation, derivatives [closed]

So I'm trying to show that when the wave function $ (-\frac{1}{c^2}\frac{d^2}{dt^2} + \frac{d^2}{dx^2})\phi(t,x) = 0 $ undergoes the Galilean transformation $ t' = t $ $ x' = x-Vt $ the resulting ...
cetuslapetus's user avatar
2 votes
2 answers
1k views

Show the Galilean covariance of Schrödinger equation

I'm trying to show the Galilean covariance of the (time-dependent) Schrödinger equation by transforming as follows: $$ \left\{\begin{eqnarray}\psi(\vec{r},t) &=& \psi(\vec{r}'-\vec{v}t,t),\\ \...
Spurious Eigenstate's user avatar
2 votes
1 answer
837 views

Galilean transformation and differentiation

Given $x=x’-vt$ and $t=t’$, why is $\frac{\partial t}{\partial x’}=0$ instead of $1/v$? $t$ seems to depend on $x’$ because if $t$ changes, $x’$ changes. Also, in this problem, $dx=dx’$ as well, but I ...
Christina Daniel's user avatar
1 vote
1 answer
1k views

Transformation of the operators $\mathbf\nabla$ and $\partial/\partial t$ under Galilean transformation

I want to know how are the transformations of the operators $\mathbf\nabla$ and $\partial/\partial t$ when the transformation of the Galilean relativity is applied. This is what I've tried: Galilean ...
Gabriel Sandoval's user avatar
1 vote
1 answer
1k views

Why are Maxwell's equations not Galilean invariant? [closed]

So i am writing an essay on the conflict between galilean invarience and maxwell's electromagnetism. I am struggling to come up with 3 evidences that they conflict because I have a mediocre ...
jambymurphy095's user avatar
2 votes
0 answers
763 views

Galilean invariance of the free schroedinger equation [duplicate]

My question follows this question: Naive interpretation of Galilean invariance of the TDSE Essentially, I'm not sure how to proceed mathematically. We have the transformations: $$\begin{cases}x'=x-...
user35687's user avatar
  • 454
1 vote
1 answer
422 views

Galilean group transformations

My problem is the following: I have difficulties in answering questions (c), (d) and (e). For (c) my answer was $\sqrt{x^{2}+t^{2}}$ and yes, the group forms the group of all isometries since the ...
Tarabostes Delectus's user avatar
6 votes
2 answers
2k views

Inonu-Wigner Group Contraction

I am trying to understand how one obtains the Galilean algebra from the Poincare algebra, specifically through the method of central extension. I'm doing this by imposing that the generators of the ...
pmal's user avatar
  • 1,062
1 vote
1 answer
342 views

Question about Galilean relativity [closed]

If a boat is moving at constant speed relative to water, on a trip between two cities, the ride upstream lasts $t_1=6~h$ and the ride downstream lasts $t_2=3~h$. What time ($t'$) will the boat need to ...
bonehead's user avatar
  • 332
0 votes
1 answer
353 views

Introduction to Special Relativity Question - Momentum Conservation

I'm currently reading a text for self-study on special relativity, Introduction to Special Relativity by James H. Smith, and I came across a question that I don't see to grasp at the moment. "Figure ...
LUX's user avatar
  • 3
0 votes
0 answers
871 views

Galilean transformation of Schrodinger equation and momentum operator [duplicate]

Let $$ \left.\begin{aligned} t'&=t\\x'&=x-vt \end{aligned}\right\} \quad \Longrightarrow\quad \dot{x}'=\dot{x}-v $$ and therefore $p'=p-mv$. If $p'=-i\hbar\nabla' $, then $\nabla'=\nabla-iv/\...
ZJX's user avatar
  • 868
0 votes
1 answer
399 views

Galilean relativity in QM

Intro I've been trying to show that the generator of boosts can be written in operator form as can be seen here, as: $$ B = \sum_i m_i x_i(t) - t \sum_i p_i $$ As a reminder the transformation ...
Yair M's user avatar
  • 705
2 votes
3 answers
2k views

Prove that the spacetime interval is not invariant under Galilean transformations [closed]

The spacetime interval $(\Delta s)^2 = (\Delta x)^2 + (\Delta y)^2 + (\Delta z)^2 - c^2(\Delta t)^2$ is invariant under the Lorentz transformation and this isn't the case for the Galilean ...
Markus Klyver's user avatar
1 vote
1 answer
3k views

Invariance of law of conservation of angular momentum under a Galilean transformation [closed]

Given a reference frame O' moving at a constant speed $\vec{V}$ in relation to another reference frame O, I want to prove that $\vec{r_{1B}} \times m_1\vec{v_{1B}} + \vec{r_{2B}} \times m_2\vec{v_{...
Melian's user avatar
  • 111
0 votes
2 answers
129 views

Does it take less time to drop a ball than fire one horizontally (with $90^{\circ}$) [closed]

So I was arguing about this with my friend. If we take two balls and drop one from a certain height H and then fire another one with horizontally with some initial speed from the same height H, which ...
Abhishek Mhatre's user avatar
3 votes
1 answer
308 views

Representations of Galilei group

Show that the operator $U(\alpha, \beta) = e^{i(\alpha \hat{x}^2 + \beta \hat{p}_{x}^2)}$ can represent the space reflection of the 1D Galilei group: $x \to -x; t \to t$. I don't really know anything ...
Mr. G's user avatar
  • 177
1 vote
0 answers
136 views

Galilean Transform

I tried to solve a problem using two different ways and I had some trouble, the problem is: We define a symmetry transform of the expected value of $\vec{P}$ like this: $$\langle \psi|\vec{P}|\psi \...
spectator's user avatar
  • 103
2 votes
1 answer
2k views

Generator of Velocity Transformations - Galilean Transformations

Under a Galilean transformation, the coordinates and momenta of any system transform as: $$ t \rightarrow t',\\ \vec r\:' = \vec r + \vec vt,\\ \vec p\:' = \vec p + m\vec v $$ where $\vec v$ is ...
user38249's user avatar
  • 379
2 votes
0 answers
456 views

Jacobian matrix of Galilean transformation

If we want to transform to another inertial frame of reference using Galilean transformation in 4-dimensional space-time, what is the Jacobian matrix of Galilean transformation?
Abdullah Almariah's user avatar
2 votes
2 answers
1k views

Velocity of an object undergoing homogenous acceleration

So I was considering the following problem within the context of Special Relativity: Given an object O, with initial velocity v, undergoing constant acceleration at a rate of a, I want to express the ...
Sidharth Ghoshal's user avatar