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I am trying to understand a paper on the Bell test experiments. I understand that if we wanted to measure the spin of a spin-1/2 particle in state $\psi$ along the z-axis we would apply the operator $$\sigma_z=
\begin{pmatrix}
1&0\\0&-1
\end{pmatrix}$$ and to measure along the x-axis we would use $$ \sigma_x =
\begi... |
I came across some problems related to finding the center of pressure. Please guide me how to go about them. Posting them all so that I can find out the intricacies involved when there are so many different geometrical shapes involved.
A quadrant of the ellipse $$x^2+4y^2 = 4$$ is just immersed vertically in a homogen... |
Could someone tell me about Frobenius-Schur indicator and the associated cups and caps notation in context of anyon model. One possible reference could be Parsa Bonderson thesis which is freely accessible here: http://thesis.library.caltech.edu/2447/2/thesis.pdf
|
I am having trouble with the unitary transformation of a certain Hamiltonian in the paper
Zhai, H. Spin-orbit coupled quantum gases. Int. J. Mod. Phys. B 26 no. 1, 1230001 (2012). arXiv:1110.6798 [cond-mat.quant-gas].
Here they transform the hamiltonian
$$
H=\begin{pmatrix} \frac{k^2_x}{2m}+\epsilon_1 & \frac{\Omega}... |
If time is discrete, such as the Planck's length, would the transition from one frame of time to the next explain why it appears matter changes from a particle to a wave? During that infinitely small space between each frame we can not measure the particle and it appears as a wave?
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Why is there a sharp cracking sound when we break a plastic ruler? The question appears to be simple and common but I need a apropriate answer.
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I have seen in Ripleys believe it or not that an opera singer generates a very high frequency of sound and breaks a glass window.How do they do it?
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Say, for sake of argument, someone was randomly transported in time and space. Would it be possible for them to determine their location on Earth and the current time using just observations of the stars?
They have no charts or equipment (not even anything to write with, so all calculations must be done in their head)... |
Lets say that functions (eigenfunctions) $\psi_0$ and $\psi_1$ are orthogonal on an interval $-d/2 < x < d/2$. Are they also orthogonal on any subinterval inside the interval $-d/2 < x < d/2$? For example if I take subinterval $$d/4 < x < d/2$$ Can I state that:
$$
\int\limits_{d/4}^{d/2}\overline{\psi}_0\psi_1\, dx= ... |
I read the Popular Science books, The Brief history of time (Hawking), The fabric of the cosmos (Greene), and The Grand Design (Hawking), etc. but did could not manage to understand what string theory is, even at a Popular level. I couldn't understand what exactly it is, even at a Popular Science level.
!
Can ... |
I am not from a physics background. I came to know this while studying probability? Is this because the planets are nearer than the stars so we get average behaviour rather than random. Is law of large number used here? Can anyone explain in detail.
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I'm currently writing a simulation in python with scipy and matplotlib to reproduce an one dimensional driven diffusive system described in this paper from M.R. Evans et al.
The system consists of positive, negative and hole particles. On the left side of the system the positive (negative) particles are produced on the... |
Wikipedia has this page on gravity assists using planets. In some cases this effect was used to accelerate the spacecraft to a higher velocity. This diagram shows this in a very oversimplified manner.
That got me thinking that if light is affected by gravity, and if it slingshots around the black hole/massive object,... |
If there is no particular absolute choice of frame of reference, the guy who sits on Earth is also moving away from the guy on spaceship perspective and hence time on Earth should also dilate when viewed from the guy on spaceship perspective. But why does the guy moving on spaceship look younger in twin paradox? What a... |
I have read in many books that BEC takes place in momentum space and in only 3-dimensions. What is meant by this statement?
|
Alright, so I am trying to find the efficiencies of a coated diffraction grating through the method in this paper. This is through a change of coordinate system. So I went through and derived all of the equations up until equation 26.
I get lost at the Outgoing wave condition. I understand what he is doing, I just g... |
I have a proton, how do I know that it is made of 2 up quarks and 1 down quark or if it is made of 3 anti-down quarks, each with different color charges?
This question is also applicable to the antiproton, is it made up of 2 antiup and 1 antidown or of 3 down quakrs?
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Let's have Lorentz group with generators of 3-rotations, $\hat {R}_{i}$, and Lorentz boosts, $\hat {L}_{i}$. By introducing operators
$\hat {J}_{i} = \frac{1}{2}\left(\hat {R}_{i} + i\hat {L}_{i}\right), \quad \hat {K}_{i} = \frac{1}{2}\left(\hat {R}_{i} - i\hat {L}_{i}\right)$
we makes algebra of the Lorentz group t... |
I have a question about the generalization of gauge transformation with two antisymmetric indices.
Starting from Eq. (3.7.6) in Polchinski's string theory book p. 108.
$$S_{\sigma} = \frac{1}{4 \pi \alpha'} \int_M d^2 \sigma g^{1/2} \left[ \left( g^{ab} G_{\mu \nu}(X) + i \epsilon^{ab} B_{\mu \nu} (X) \right) \partia... |
For a hypothetical vehicle traveling in an Alcubierre bubble at faster-than-light (FTL) velocities, what would happen when the leading edge of the bubble encounters incident particles or photons?
Let's say either a stationary particle of matter, a photon traveling in the opposite direction to the vehicle, or a photon t... |
My question is related to the first page of this article regarding the big bang theory and refers to this specific sentence:
Armed with the best physics of the 20th century, Albert Einstein came to very similar conclusions with his theory of relativity. Just consider the effect of mass on time. A planet's hefty mass w... |
The models/depictions I've seen of warp bubbles show space compressed ahead of the bubble and expanded behind, so that the space inside the bubble moves with respect to the space outside. If that is so, then what is happening at the sides? It would seem that there is some sort of shear taking place between the space in... |
I want to know from the smallest possible originating structures how the light I see generated from heat is made by atoms themselves.
|
At CMB recombination (z=1090), what is the radial extent of the last scattering "shell"?
a) Delta(z) = ....
b) Delta(comoving angular distance)= ....Mpc
The WMAP first-year parameters give
Delta(z) = 195. Is this still correct?
|
I know that two functions which describe the state of a particle in an infinite square (on interval $-d/2<x<d/2$) well are like:
\begin{align}
\psi_{even}&= \sqrt{\frac{2}{d}}\sin\left(\frac{N\pi x}{d}\right)\quad N=2,4,6\dots\\
\psi_{odd} &= \sqrt{\frac{2}{d}}\cos\left(\frac{N\pi x}{d}\right)\quad N=1,3,5\dots
\end{a... |
Say I have an object that starts falling from rest at 2 m/s2. Its total displacement and velocity at the end of every second should look something like this:
t d v
1 2 2
2 6 4
3 12 6
4 20 8
At the end of the first second, it should have accelerated to 2 m/s and moved 2 m. At the end of 4 s... |
If we consider the 126 Higgs-like boson as a pseudo-Nambu-Goldstone boson, what are the experimental fingerprints of that case? What are the main differences, in a purely effective field theory approach and/or "new physics" scenario with respect to the fundamental and boring Standard Model Higgs (take it as a neutral s... |
Given that the universe is expanding because space itself is expanding, is that expansion occuring in all places and on all scales? Consider a photon emitted from a source billions of years ago. As it travels, space is expanding all around it. If that photon is unchanging, wouldn't that mean that its apparent wavelengt... |
The Church-Turing hypothesis says one can not build a computing device which has more computing power (in terms of computability) than the abstract model of Turing machine. So, there is something in our laws of physics which prevent us from making devices which are more powerful than Turing machine, so in this respect ... |
There are many ways to introduce the electromagnrtic field in Quantum Field Theory(QFT), such as canonical quantization method which introduces the creation and annihilation oprators by treating the amplitudes of electromagnetic waves as the operators.
One way I have read in book is different, but I don't understand.
A... |
Lorenz and Coulomb gauge-fixing conditions. What is physical difference between these two gauge-fixing conditions? Mathematical expression are clear but how to we choose one of these means what they really means.
|
For the the group velocity of a wave packet, the group velocity is the partial derivative of omega with respect to the wavenumber, what does this mean? I thought that for some given wave packet both the angular frequency and wave number should be fixed, so what differentiation $d$ is there?
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As far as I've read online, there isn't a good explanation for the Born Rule. Is this the case? Why does taking the square of the wave function give you the Probability? Naturally it removes negatives and imaginary numbers, but why is it the square, not the fourth or some higher power?
|
White light is always said to contain all the different wavelengths of light. Why, then, can we 'make' new colors simply by adding wavelengths? Is it just a matter of our perception, that, when two colors are added together, they appear to be the wavelength of another color. Or are the waves actually forming into anoth... |
The question is to finde the initial horizontal velocity of the ball at end of the ramp, where it is released.
I know how to do this using gravitational potential energy and kinetic energy ($v=\sqrt{2gh}$), assuming all potential energy is converted into kinetic energy but the question is asking me to find the error in... |
I would like to ask how I can reduce uncertainty by designing an experiment.
I need to measure a quantity( say speed, in m/s). I have to calibrate the device and then move the device to measure this.
I would like to reduce the uncertainty by using two devices to measure the same quantity.
If I calibrate the devices t... |
At sunrise, the sky isn't actually up in the sky yet. Twilight occurs before sunrise, then at sunrise the leading part of the sun crosses the horizon. But, the sky isn't bright yet. It takes some time for the sky to be blue again.
Then, at the closing of the day, the sky darkens before twilight, then sunset.
Basically,... |
1. The problem statement, all variables and given/known data
Electron of is in a 1-D potential well of depth $20eV$ width $d=0.2 nm$ in his ground
state $N=1$. What is the energy of the ground state? Write the
normalized wavefunction of the ground state. What is the probability,
to find the particle outside the ... |
I had been fascinated to hear that anything can be swallowed by a black hole. But what causes such a huge amount of gravitational force?
|
I tried calculating the downforce of a spoiler I need for a robot. I used this formula.
$$F = \frac{1}{2}Ac_a\rho v^2$$
Where $\rho$ is air density, $v$ is the speed of my robot, $c_a$ is the lift coefficient and $A$ is the windage of the spoiler which I calculate by multiplying its width, length and angle of attack in... |
What type of magnetic fields does a Hall effect semi-conductor pick up on? AC or DC fields? How would one go about building a device that measures AC Magnetic fields?
|
An Alcubierre Drive is a hypothetical device that can move a place someplace else faster than the speed of light without violating known laws of physics.
This paper provides some equations as to the energy density in such a field, as well as proposals about testing the theory experimentally and finding modes of applic... |
In analogy to piezoelectric materials, where the application of an electrical field creates mechanical deformation in the material, I have the following question.
Are there solid materials whose porosity can be altered or controlled?
Of course, I have googled this. This lead me to a lot of websites where controllable p... |
I am reading Cheng and Li. On page 9, it is written that the coefficient $\frac{1}{2 \cdot (4!)^2}$ for the second order term of the four point function becomes just $\frac{1}{2}$ for the following diagram:
I am not getting that answer. Call the vertices in the diagram $y_1$ and $y_2$. Imagine $y_1$ and $y_2$ as a poi... |
I'm sure many of us are familiar with the following plot showing the running of the inverse of the fine-structure constants of the SM.
(I got the picture from google)
At one-loop, the expressions for the fine-structure constants of the hypercharge, weak, and color gauge groups are,
$$\frac{1}{\alpha_1 (\mu)} \approx ... |
I have a question in deriving Eqs. (3.6.15b) and (3.6.15c) in Polchinski's string theory vol I p. 105.
Given
$$\Delta (\sigma,\sigma') = \frac{ \alpha'}{2} \ln d^2 (\sigma, \sigma') \tag{3.6.6}$$
where $d(\sigma,\sigma')$ is the geodesic distance between points $\sigma$ and $\sigma'$.
It is said for the Weyl vari... |
I understand that bounded states in quantum mechanics imply that the total energy of the state, $E$, is less than the potential $V_0$ at + or - spatial infinity. Similarly, the scattering state implies that $E > V_0$.
But I do not understand why for bounded states, the complete set of wave-function solutions to the tim... |
Why does the attractive Dirac delta distribution (function) potential $V = \alpha\delta(x)$ (for negative $\alpha$) yield both bound AND scattered states? Is this due to the definition of the Dirac delta distribution? Or is it for a different reason?
|
This article at NewScientist magazine (subscription required) describes entangling photons by passing them through a half silvered mirror.
http://www.newscientist.com/article/mg21929282.100-quantum-weirdness-the-battle-for-the-basis-of-reality.html
It talks about the "weirdness" of entanglement and how it means that ei... |
I've just read that 68 years ago Little Boy was dropped on Hiroshima, which made me wonder about some rather historical facts about the development of the first nuclear bombs; they seem to be several questions, but they boil down to the same thing: the theoretical aspects of the development of the bombs.
As far as I kn... |
I know of X-Ray diffraction, which produces a pattern corresponding to the inverse Fourier Transform of the lattice (reciprocal lattice). While this method is widely employed, it provides more information than I need - I don't want to find out what Bravais lattice I'm examining, but just how homogeneous this lattice is... |
I need to compute the power factor for two ideal impedances, a capacitor:
$$Z_C=\frac{-j}{\omega C} $$
and a inductor:
$$Z_L=j\omega L $$
I know that the power factor is defined as a term $\cos(\phi)$, but I don't know how to compute it in terms of $Z_C$ and $Z_L$. Moreover I need to discuss wether $\cos(\phi)$ is a fu... |
Final edit: I think I pretty much understand now (touch wood)! But there's one thing I don't get. What's the physical reason for expecting the correlation functions to be independent of the cutoff? I.e. why couldn't we just plump for one "master Lagrangian" at the Planck scale and only do our integration up to that poi... |
Lets say we have a particle in a infinite square well which has a wavefunction like this ($A$ is some constant and $d$ is the width of the well):
\begin{align}
A\left[ \sin \left(\frac{2 \pi x}{d}\right) + \frac{1}{3}\sin \left(\frac{3 \pi x}{d}\right)\right]
\end{align}
How do we know from which stationary states this... |
Please bear with me, as I'm not in the field of physics, this question may seem a bit simple.
This question is concerning stable circular orbits around celestial bodies.
I know the equation relevant to my question is given by the equality of gravitational to centripetal force:
$$G\frac{mM}{r^2}=\frac{mv^2}{r}$$
where $... |
The reasoning leading to the Schrödinger equation goes as follows:
A plane wave in empty space has the following form:
$$\psi = e^{i(kx-\omega t)}$$
Einstein had previously explained the photoelectric effect, i.e. the emission of electrons from a metal surface through light, by suggesting that light is made from photon... |
I met some problem about the Virasoro operator in "old covariant quantization" in Polchinski's string theory vol I p 123.
It is given
$$L_0^{\rm m}=\alpha' p^2 + \alpha_{-1} \cdot \alpha_1 + \cdots \tag{4.1.11a} $$
But on p 59,
$$ L_0 = \frac{ \alpha' p^2 }{4} + \sum_{n=1}^{\infty} ( \alpha^{\mu}_{-n} \alpha_{\mu n} ... |
Basically, I would really like it if somebody just explained to me what is going on here. Please use any physics lingo you feel is necessary, but explain what you mean. I am just having trouble finding a nice explanation without having to know tons of physics. ( I have a fifth grade physics level)
So the reference I ha... |
A wavefunction is inherently a multi-particle function. If you have a container that is perfectly isolated from the external universe (not possible, but just imagine it) and filled with $n$ particles, then the information necessary to perfectly describe everything there is to know about that system would be contained ... |
My questions are based on this paper - http://arxiv.org/abs/0905.4013
Firstly I want to know as to whether some assumptions are needed about the relationship between the systems $A$ and $B$ for the Hilbert space to factor as tensor products as ("assumed"?) on page 3?
I mean assume the more common reverse scenario - if... |
How does an atomic transition between ground and excited states depend upon the direction of polarisation of incident light?
|
The formula for calculating the center of mass is
$$ r_{center} = \frac{m_1 \cdot r_1 + m_2 \cdot r_2}{m_1+m_2} $$
Why can't I use it to calculate the barycentre of two planets?
I understand how to use ratios to approach this problem.
$$ \frac{r_1}{r_2} = \frac{m_1}{m_2} $$
$$ r_1 = \frac{m_2}{m_1+m_2}\cdot (d_{Sun->... |
How do we calculate the expectation value for speed? I have heard that we must first calculate the expectaion value for kinetic energy. Someone please explain a bit what options do we have.
|
I'm trying to diagonalize the Hamiltonian for a 1D wire with proximity-induced superconductivity. In the case without a superconductor it's all fine. However, with a superconductor I don't get the correct result for the energy spectrum of the Hamiltonian in
Tudor D. Stanescu and Sumanta Tewari. “Majorana fermions in ... |
If the air is flowing with the earth, as it rotates, how do we feel a breeze and strong winds at times, as everyone has experienced, the wind shifts as if from many directions.
|
I'm on earth and we have two spaceships $A,B$. They can instantaneously accelerate to certain velocities $v_A,v_B$.
We want to travel to another planet which is $\Delta x$ lightseconds away, and we want the ships to arrive at the same time. The universe as such doesn't change during the traveling time.
How mu... |
In Fermi's golden rule
$$P_{ab}(t)=2\pi t/\hbar \left|\langle\psi_b|V|\psi_a\rangle\right|^2 \delta(E_f-E_i)$$
for transition probability from state $a$ to $b$, how can the probability grow with time to above 1, how does one interpret a probability above 1? How does one use this formula?
And in this formula for the a... |
On our modern physics class my professor did a problem:
Write down a wavefunction of an electron which is moving from left to right and has an energy $100\text{ eV}$.
At first i said: "Oh i know this!" and solved the case like this.
My solution:
The energy $100eV$ must be the kinetic energy of the electron. So i said... |
The Virasoro algebra has a finite $sl(2)$ sub-algebra generated by $L_{-1}$, $L_0$ and $L_{+1}$. Let's consider a unitary highest weight representation of the Virasoro algebra with conformal weight $h>0$ and central charge $c>1$. How does this representation decompose under the $sl(2)$ sub-algebra?
It is clear that the... |
Consider an object travelling near the speed of light relative to us (let it be a spaceship or a star), which is emitting light (consider it monochromatic resulting from a two level electronic transition).
Regarding the different relative time in the object itself (since it's travelling at high speeds) and the time of ... |
Magnetic levitation has been used to suspend frogs in midair. I was wondering: Does the animal still feel gravitational pull? I mean: Does the frog feel like an astronaut on the ISS, or does he feel like a trapeze artist suspended by a harness?
|
I'm intending to study General Relativity on my own. The thing is, my physics background is not very strong. I know classical mechanics and I know some electromagnetism. I'm familiar with Gauss' law, Ampere's law, RLC circuits, ... but I still have problems with the intuition behind concepts like 'momentum'. I know tha... |
The work function of any metal is no doubt constant for it is related to electromagnetic attraction between electrons and protons. However on increasing the intensity of any light source the kinetic energy of the emitting electrons must increase, mustn't it? Let us assume there is only 1 electron in a metal surface. Le... |
A balloon with volume 2800 m³ is heated up to 60 °C.
If the outer temperature is 12 °C and the air has a pressure of 960 hPa, what is
the density of the air inside the balloon and on the outside?
In the solutions they used the following formula: $ \rho_1 = \rho_0 \cdot \frac{P_1}{P_0} \cdot \frac{T_0}{T_1} $
Howe... |
I have hit a roadblock in my simulation, where there are 2 authors with contradicting equations on the model.
So I have simulated both, and drew it out for a few diameters. My dish size is 40m.
I am unsure which model to use for laser transmission over 40,000km from space to Earth. The more intuitive/logical model is t... |
Despite Planck's constant being in $E=hf$, it would appear to me that energy is still not discrete, as frequency can be an fraction of a Hertz that one wants. How does this imply that electromagnetic radiation is quantized?
|
I've seen the 'derivation' as to why momentum is an operator, but I still don't buy it. Momentum has always been just a product $m{\bf v}$. Why should it now be an operator. Why can't we just multiply the wave function by $\hbar{\bf k}$? Why should momentum be a derivative of a wave function?
|
A stone of mass $m$ is attached at one end of a vertical spring whose another (upper) end is fixed at horizontal surface. During the motion, a spring takes vertical direction. Force in spring is proportional to extension.
How can I determine equilibrium position?
Will it be in equilibrium when forces that act on it ... |
To even suggest the great Einstein is incorrect on anything he has written is inconceivably absurd. Being fully aware of this I do indeed dare to not only suggest he is wrong but I cannot believe nobody has questioned his cosmic speed limit to this very day. I do not need any mathematical equations to prove this point.... |
In Peeble's "Large scale structure of the Universe"
the Newtonian approximation in cosmology is examined by looking at a transformation that makes the metric locally Minkowski. On pg 38 it is stated that
To make $g_{ij,kl}=0$, we would add 10$\times$10 equations for a total of 150 to be satisfied by the choice of 56+... |
Is there any difference between locality and separability in quantum mechanics, or do they mean the same thing? It seems authors do not always agree.
|
At 1 G, we feel at home.
At 5 G's, normal people can stay awake.
At 9 G's, trained pilots with G-suits can stay awake.
At 25 G's, R.I.P.
Unfortunately, these numbers are limiting for space travel, especially for the astronaut. For example, if you and I wanted to visit Alpha-Centauri (4.2 light-years away) and come bac... |
I have a question about "old covariant quantization" in Polchinski's string theory p. 123.
It is said
The only nontrivial condition at this level is $(L_0^{\rm m} + A) | \psi \rangle =0 $, giving $m^2=A/\alpha'$.
I have no idea where does $m^2=A/\alpha'$ come from... How to get this result?
|
As time passes more slowly in a region of space close to the source of a gravitational field, shouldn't the moon, which always has one side facing towards the earth, have a higher fraction of radioactive isotopes on that side than on the far side? Could the fraction be used to determine the time tidal locking occured?
... |
Is it possible for dark matter to create the regular matter that we, the stars, and the galaxies are made of? The reason I'm asking this is because I have a hard time imagining how something can basically just come out of nothing (The Big Bang). So I was thinking, what if there was dark matter "before" big bang. Is it ... |
As you know the equation of capillary action is given by:
$$h=\dfrac{2\gamma\cos\theta}{\rho gr}$$
Where:
$h$ is the height the liquid is lifted,
$\gamma$ is the liquid-air surface tension,
$\rho$ is the density of the liquid,
$r$ is the radius of the capillary,
$g$ is the acceleration due to gravity,
$\theta$ is... |
I've seen the Kerr metric usually presented in the Boyer-Lindquist coordinates where there is a cross term in the $d\phi$ and $dt$ term. I've done a good bit of searching and cannot find any coordinates which express the Kerr metric in an orthogonal fashion. Is there ANY choice of coordinates that eliminates all cross ... |
Consider a cement block of the same density as sea-water resting on the (perfectly polished) seafloor. I also assume the side-faces of the cement block are highly polished, so that no vertical hydrostatic forces can attack on them. A cable is attached to the top of the block.
My question ist: How much force must one ap... |
I would be interested in what people think of Fulvio Melia's argument for a linearly expanding Universe.
I realize that the experimental evidence seems to be pointing to an accelerating Universe but does Melia's argument have any merit?
The following is my own Newtonian argument for a linearly expanding universe (it is... |
This might be a naive question, but how can an object such as a black hole singularity have infinite density but finite mass? (For example, we can approximate the mass of a black hole based on Kepler's Laws and use info from surrounding movements of stars to determine the central mass, but the black hole, excluding the... |
I've been having a bit of trouble wrapping my mind around this.
If I were in a ship going 77% the speed of light (enough to experience reasonable time dilation) would I see earth going in fast forward? Would people on earth see my ship moving very slowly?
I have this question because I was reading Physics of the Impos... |
I read an interesting article
http://m.machinedesign.com/news/motor-sizing-made-easy
It is very interesting, but I can not follow the 2nd last paragraph. I don't understand why it is true.
Gearboxes offer a significant benefit in that they affect the inertia ratio by a factor of the gearbox ratio squared.
Please help. ... |
Motivation.
I was recently reviewing the section 3.10 in Sakurai's quantum mechanics in which he discusses tensor operators, and I was left desiring a more mathematically general/precise discussion. I then skimmed the Wikipedia page on tensor operators, and felt similarly dissatisfied. Here's why
In these discussions... |
I think I'm missing something with torques. I seem to have gotten myself confused.
I have a box that's centered at ( 0 , 0 , 0 ) with length ( $x$ dimension ) = 1 , width ( $y$ dimension ) = 0.25, and height ( $z$ dimension ) = 0.5. The edges are parallel to the axes. The $x$ axis is left(-) and right(+), the $y$ axis ... |
I am much interested in physics. I have been caught up with one serious question related to speed of light. Hearing about Large Hadron Collider (LHC), it is said that protons in there are accelerated to almost the speed of light, i.e., $3\times10^8$ metre per second. One can be sure that the length in which the above e... |
This is not a question about traditional nuclear power plants vs the thorium based. But about the Fukushima plant itself and the very negative environmental effects from its meltdown of reactors 1 and 3 vs a Thorium based design under similar natural stressors.
Fukushima leaking radioactive water for ‘2 years, 300 ton... |
In electrostatics, we have $$\nabla \times \vec{E} = 0$$. Hence, we can define a scalar potential $V$, where $$\vec{E} = -\nabla V$$. We know from Faraday's law that $$\nabla \times \vec{E} = -\frac{\partial \vec{B}}{\partial t}$$. In situations involving constant currents(D.C.) the rate of change of the magnetic field... |
As we know, the phenomena of fractionalizations in condensed matter physics is fantastic, like fractional spin, fractional charge , fractional statistics, .... And one key point is that the quasiparticals must be created or annihilated by pair.
On the other hand, consider the groups $SU(2)$ and $SO(3)$, they are the ro... |
The both sides of below equation don't give the same units, e.g.
$$
\frac{\delta}{\delta \phi (\tau)}\int_a^b \phi (\tau') d\tau'=1\;.
$$
where $a<\tau<b$. To show this assume that the field $\phi$ has "$j$" unit and $\tau$ has "$s$" unit then
$$
[\frac{1}{j} j s] \neq [ 1 ].
$$
What's wrong with my reasoning?
|
I'll prefix this question by stating that I am not a physicist, I am a programmer. I am working on updating a (very old) program that calculates the performance of a magnet. This whole program is in CGS units and it is required of me to change it to SI units.
A particular equation in this program gives the Gauss/square... |
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