Hi,
I'm reading A Student's Guide to Lagrangians and Hamiltonians by Patrick Hamill and, in the following section on generalized velocity, I'm wondering if we should have ##\delta_{kj}## rather than ##\delta_{ij}##?
Many thanks.
4
I am working on problem c and I'm not sure if I'm doing it right, please can you help me understand if I am on the right lines? I want to get a better understanding of lagrange method problems
Here is my working:
I have labelled ##k_1,k_2,k_3,k_4, k_5## left to right
Generalised...
I am looking at a textbook solution to the following problem of finding the equation of motion of a half disk. In the solution, the author considers the half disk has a COM at the black dot, and to find the instantaneous translational velocity of the center of mass (he considers rotational...
If the standard model Lagrangian were generalized into what might be called "core capabilities" what would those capabilities be? For example, there are a lot of varying matrices involved in the standard model Lagrangian and we can generalize all of them as the "core capability" of matrix...
Because it drives to contradictions. Here is a nice example from E. Rosinger Generalized solutions of nonlinear PDE.
We can multiply generalized functions from ##\mathcal D'(\mathbb{R})## by functions from ##C^\infty(\mathbb{R})##. This operation is well defined. For example $$x\delta(x)=0\in...
Hi Pfs,
There are different kinds of entropies.
I discoved the free entropy.
https://arxiv.org/pdf/math/0304341.pdf
the second law says that the total entropy cannot decrease when time goes by.
Is it always the same "time" for the different entropies?
the author, Voiculescu, wrote articles...
Is there a general expression for the wave function $\psi$, which describes the electronic properties of an arbitrary covalent bond? For example is it equal to some sort of trigonometric expression?
In Lagrangian mechanics we learn about generalized forces. However, I haven't seen these explicitly mentioned in books on QFT. Can the Lagrangians of QED or QCD be expressed in terms of generalized forces or is there some connection there, in particular to the Nielsen form.
My tests are submitted and marked anonymously. I got a 2/5 on the following, but the grader wrote no feedback besides that more detail was required. What details could I have added? How could I perfect my proof?
Beneath is my proof graded 2/5.
My tests are submitted and marked anonymously. I got a 2/5 on the following, but the grader wrote no feedback besides that more detail was required. What details could I have added? How could I perfect my proof?
Beneath is my proof graded 2/5.
Hi Pfs
When instead of the variables x,x',t the lagrangiean depends on the trandformed variables q,q',t , time may be explicit in this lagrangian and q' (the velocity of q) may appear outside. I am looking for a toy model in which tine is not explicit in L but where the velocities appear somhere...
Here is an image for better illustration,
I only managed to solve for (a) but I'm not sure if I did it right. As for (b) and (c), I have no idea how to do it.
My answer for (a):
=> Ki + Ui + Wext = Kf + Uf
=> 0+mgh1-LμmgCosΘ = 1/2mv^2 + mgh2
=>1/2v^2 = gh1- gh2 - LμgCosΘ
=> V = √2g(h1 - h2 -...
Wikipedia article under generalized forces says
Also we know that the generalized forces are defined as
How can I derive the first equation from the second for a monogenic system ?
There is an entry in Wikipedia at this link: https://en.wikipedia.org/wiki/Pythagorean_triple
Under elementary properties of primitive Pythagorean triples, general properties,sixth bullet from the bottom of this section, there is this generalized Diophantine equation:
x^2p + y^2p = z^2
Where: p...
Hi,
I have a set of ODE's represented in matrix format as shown in the attached file. The matrix A has algebraic multiplicity equal to 3 and geometric multiplicity 2. I am trying to find the generalized eigenvector by algorithm (A-λI)w=v, where w is the generalized eigenvector and v is the...
Hi to all, I ask if somebody of the Physics community know good references for article where the author works with generalized canonical commutation relations ( I mean that the author works with ##[x,p]=ic\hbar## with ##c## a real constant instead of ##[x,p]=i\hbar##).
Thank you for the answers...
hi guys
my analytical mechanics professor asked a question the other day about, how come the generalized forces##Q_{\alpha}## doesn't need to have a dimension of force, and the generalized coordinated ##q_{\alpha}##as well doesn't need to have a dimension of length, but the generalized work...
I want to take the derivative of a composite function that looks like
$$f( g(x), h(x) ).$$
I know from Wolfram that the answer is
$$\frac{ df( g(x), h(x) ) }{ dx } = \frac{ dg(x) }{ dx }\frac{ df( g(x), h(x) ) }{ dg(x) } + \frac{ dh(x) }{ dx }\frac{ df( g(x), h(x) ) }{ dh(x) }.$$
We can...
hi guys
i am trying to follow a proof of the generalized uncertainty principle and i am stuck at the last step :
i am not sure why he put these relations in (4.20) :
$$(\Delta\;C)^{2} = \bra{\psi}A^{2}\ket{\psi}$$
$$(\Delta\;D)^{2} = \bra{\psi}B^{2}\ket{\psi}$$
i tried to prove these using the...
In the discussion of the pressure in macrocanonical ensemble, I found in textbook that:
##dW = \bar p dV## (##dW## is in fact d_bar W, yet I can't type the bar)
The derivation goes like:
##\bar p = \frac{1}{Z} \sum_{r} e^{-\beta E_r} (-\frac{\partial E_r}{\partial V}) = ... = \frac{1}{\beta}...
Good Morning
Could someone give me some numbers for a Generalized EigenValue problem?
I have lots of examples for a 2 x 2, but would like to teach the solution for a 3x3.
I would prefer NOT to turn to a computer to solve for the characteristic equation, but would like an equation where the...
So formulating them was easy, just set ##C:=D\cup E## in (1) and set ##C:=D\cap E## in (2) to see the pattern, if ##\mathfrak{B}## is a non-empty collection of sets, the generalized laws are
$$A-\bigcup_{B\in\mathfrak{B}} B = \bigcap_{B\in\mathfrak{B}}(A-B)\quad (3)$$...
Summary: The problem is to generalize the Lorentz transformation to two dimensions.
Relevant Equations
Lorentz Transformation along the positive x-axis:
$$ \begin{pmatrix}
\bar{x^0} \\
\bar{x^1} \\
\bar{x^2} \\
\bar{x^3} \\
\end{pmatrix} =
\begin{pmatrix}
\gamma & -\gamma \beta & 0 & 0 \\...
As you can see from my eigenvalues, here I've got a repeated roots problem. I'm wondering if it matters which variable I can choose to be the free variable when I'm solving for the generalized eigenvector. I think both are equally valid but they look different from one another and I'd like to...
The Coriolis potential last term of (42) is obtained by integration through r and R from last term of (40).
I do not understand why we do not need to integrate through v as well, since the Coriolis force depends on v?
Homework Equations
Equation (41) is wrong I think, L must be replaced by...
Generalized momentum is covariant while velocity is contravariant in coordinate transformation on configuration space, thus they are defined in the tangent bundle and cotangent bundle respectively.
Question: Is that means the momentum is a linear functional of velocity? If so, the way to...
I'm just getting into 3D quantum mechanics in my class, as in the hydrogen atom, particle in a box etc.
But we have already been thoroughly acquainted with 1D systems, spin-1/2, dirac notation, etc.
I am trying to understand some of the subtleties of moving to 3D. In particular, for any...
I am trying to prove the generalized associative law with induction, but am being tripped up by one aspect. I am reading a solution and it says for the induction step argue that any bracketing of the product ##a_1 \cdot a_2 \cdot \cdots a_n## must break into two subproducts ##(a_1 \cdot \cdots...
Hi,
Just wanted to see if I understood the meaning of Generalized Linear Models:
In the case of Standard ( "Non-generalized") Linear models, a dependent variable y is a linear function of a dependent variable x. In a Generalized Linear Model (GLM), a dependent variable y is linear in some...
@vanhees71 reminds us that
which suggests something I've wondered about for a while, whether dark matter might be adequately modeled by generalized free fields, which do not have asymptotic free states. Ray Streater, in Rep. Prog. Phys. 1975 38 771-846, "Outline of axiomatic relativistic...
Homework Statement
a: In plane polar coordinates, find the scalar product of the vector (0,1) with itself.
b: What would be the r, θ components of the unit vector in the θ direction?
Homework Equations
Scalar product of 2 vectors = AαgαβBβ
The Attempt at a Solution
For part a, I used the...
From "A Student's Guide to Langrangins and Hamiltonians", Patrick Hamill, Cambridge, 2017 edition.
Apologies: since I do not know how to put dots above a variable in this box, I will put the dots as superscripts. Similarly for the limits in a sum.
On page 6,
"we denote the coordinates by qi...
initially my attachment/picture has been cut off that link http://sun.stanford.edu/~sasha/PHYS780/PLASMA_PHYSICS/phys780_2014_l13.pdf page 6
Also I would like to put into words that divergence of current density is accepted as 0 in continuous loop( no capacitors exist...). But if you look at...
I wondered if anyone might know of any open access materials, possibly lecture notes, on the content of the following papers or books.
P.A.M Dirac, 1950, Can. J. Math. 2,147 "Generalized Hamiltonian Dynamics"
P.A.M Dirac, 1933, Proc. Camb. Phil. Soc., 29, 389 "Homogenous variables in classical...
Homework Statement
[/B]
In this example, I know that I can define the horizontal contribution of kinetic energy to the ball as ##\frac{1}{2}m(\dot{x} + \dot{X})^2##.
In the following example,
Mass ##M_{x1}##'s horizontal contribution to KE is defined as ##\frac{1}{2}m(\dot{X} -...
I'm trying to expand the following using Newton's Generalized Binomial Theorem.
$$[f_1(x)+f_2(x)]^\delta = (f_1(x))^\delta + \delta (f_1(x))^{\delta-1}f_2(x) + \frac{\delta(\delta-1)}{2!}(f_1(x))^{\delta-2}(f_2(x))^2 + ...$$
where $$0<\delta<<1$$
But the condition for this formula is that...
As per my understanding, a linear equation with two variables form a line segment (ax=by+c or ax+by=c) and linear equation with three variables form a plane (ax=by+cz+d or ax+by+cz=d). Am I right? And if I am right, does an equation with four variables form a cube?
When discussing about generalized coordinates, Goldstein says the following:
"All sorts of quantities may be impressed to serve as generalized coordinates. Thus, the amplitudes in a Fourier expansion of vector(rj) may be used as generalized coordinates, or we may find it convenient to employ...
Homework Statement
Write the Galilean coordinate transformation equations
for the case of an arbitrary direction for the relative velocity v of one frame with respect to the other. Assume that the corresponding axes of the two frames remain parallel. (Hint: let v have componentsvx, vy, vz.)...
Hello everyone
I am trying to write code in ROOT.I want to plot generalized hypergeometric function pFq with p=0 and q=3 i.e I want to plot 0F3(;4/3,5/3,2;x) as a function of x using TF1 class.I am not getting how to plot this function in ROOT.Kindly help me out.
Thanks in Advance
Consider a sphere constrained to roll on a rough FLAT HORIZONTAL surface. A book on classical mechanics says it requires 5 generalized co-ordinates to specify sphere's configuration: 2 for its centre of mass and 3 for its orientation.
I did not understand why 3 for orientation. I guess only 2...
Homework Statement
A particle of mass m slides without rolling down on a inclined plane, Find the generalized force and the Lagrangian equation of motion of mass m.
Homework Equations
T = (mx'^2)/2
Generalized force Q=-d/dx(V)
The Attempt at a Solution
To find the generalized force first I...
hello guys
i like physics specially the classical dynamics but am finding it hard to understand those letters (i , j ) now am studying about the generalized forces corresponded with generalized coordinates
and there is an equation in the attached pic with this thread
can anybody help me and...
I know that for rigid bodies only the work-energy theorem states that the net work done on the body equals the change in kinetic energy of the body since a rigid body has no internal degrees of freedom and hence no other forms of energy such as potential energy. Is there a most generalized form...
In basic level classical mechanics I've known so far
The Lagrangian Equation is
Like this
But in the little deeper references, they covers Lagrangian Equation is
Like this
Qi is Generalized force, and Qi also contains frictions that's what reference says
But I still can't grasp.
What is the...
Hello everyone,
I was trying to develop a sort of generalized version of the Fourier Transform. My question in particular is:
Given a function f(x,u), is there a function g(x,u) with \int_{-\infty}^\infty f(x,u)g(x,u')\mathrm{d}x=\delta(u-u')
For f(x,u)=e^{2\pi ixu} the solution would be...
I would like to give me a simple definition about the generalized Sundman transformations and how we use it to solve the second order differential equation.