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Recently I've read some papers on inflation and slow roll approximation. As we all know, inflation parameters are constrained by recent Bicep2/Keck and Planck data, which gives values of scalar-to-tensor ratio as well as spectral index of primordial curvature perturbations - i have simple or even naive question - since... |
I want to know how we can determine the probability of various states of hydrogen as there are infinite of them, or electron in a hydrogen atom is in the superposition of which states, maybe it is in the superposition of degenerate states? I don't know, i am just guessing, please help.
|
In the following equation I would like to check what the terms represent intuitively (in a hand-wavey sense - I know $\underline{D}$ is not a physical thing so it's not possible to fully describe it in a physical way):
$$\underline{D}=\epsilon_0 \underline{E}+\underline{P}$$
Am I correct with the following?
$\underline... |
Reading Schwartz's book on Quantum Field Theory, one finds on page 120 that the forward polarization for a massless spin 1 field is $\epsilon_{f}\propto p_{\mu}$. This is equivalent to $A_{\mu}=\partial_{\mu}\phi$ and hence it corresponds to pure gauge and is therefore not normalizable.
When he talks about massless spi... |
Since clouds exist in lumps and are non-uniformly distributed, one would expect rainfall to be non-uniform as well. But as far as I can tell, rainfall is more or less uniform over a large region.
I suspect that turbulence might be at play here and cause the dispersal of raindrops, but I'm not really sure.
EDIT: I agree... |
Near the end of my introductory quantum mechanics lectures the lecturer introduced multi-particle states with distinguishable particles, notably product states
$$|\psi \rangle = |\psi^{(1)} \rangle ... |\psi^{(N)} \rangle$$
with upper indices running over N particles
As an example of an operator acting on several parti... |
Just a lighthearted question for the summer :)
I was at the supermarket the other day, and I wanted to buy a watermelon; great straight out of the fridge, to chill and rehydrate in this sweltering hot weather.
The wisdom my grandma (a farmer in her day) had tried to impart was failing me. I could only vaguely remember ... |
I am a tenth grade student.
Actually I have two questions.
I read that internal resistance of a cell decreases if the temperature of the electrolyte increases.
But isn't it contradicting what is said before: "resistance increases with increase in temperature".
I think if temperature will increase then the molecules a... |
What is the minimum energy required to move a unit of heat from the cold side of a system to the hot side?
One obvious lower bound is that it must be at least as much as the amount of work that can be done by a maximum efficiency heat engine when that heat moves back. So for example, for a system with the cold end at 0... |
Suppose that there is a system of two photons 1 and 2, each of which is in a mixed state $1/2|R\rangle\langle R| + 1/2 |L \rangle\langle L|$, where $|R \rangle$ and $\langle L|$ are two orthonormal pure polarization states. (So the composite state would be a product of two mixed states.)
How is this case different from... |
It's my understanding that galaxies formed from accretion of intergalactic matter around supermassive black holes. As the universe expands the amount of matter entering a galaxy decreases, until at some point this process stops or becomes negligible.
At which point in the past or the future will matter accretion from t... |
I have watched several videos on both rocket launches, ballistic missile launches, even a really cool one by Northrup Grumman on launching a nuclear missile.
(https://www.youtube.com/watch?v=HWZXinRwCaE)
I understand why missiles have a pitch maneuver. I have watched videos such as (https://www.youtube.com/watch?v=kB-... |
Both INS and IXS can be used to study phonon dispersion relations. While INS requires large sample size due to low inelastic scattering cross section, IXS using synchrotron x-ray sources do not require a small sample as extremely intense synchrotron x-rays can be incident on small sample area. Therefore, is INS any goo... |
I am kind of stuck with a problem mentioned in my current reading about special relativity. Given the Lorentz transformation
$$x^{\bar{i}} = L^i{}_k \, x^k \quad ,$$
one has to find the transformation law for the "ordinary" velocity ( =: 3-velocity) of a particle described by its spatial coordinates$\, \textbf{x}(t) \,... |
In (arXiv:1409.2454), page 9, Mermin states that
(...) fundamental QBist fact that a quantum mechanical description is always relative to the particular user of quantum mechanics who provides that description (...)"
I don't see how this makes sense. I cannot find out a single instance where two different experimenter... |
I have myopia so I wear corrective lenses. One set of glasses I have is designed to focus from about 2 feet to infinity. I can see the dashboard of a car, but I can also see buildings at long distances and they look sharp and in focus.
However, when I look at the night sky, the stars do not seem to be perfectly in focu... |
If a glass of certain colour is heated, then how can we determine the corresponding colour that it will glow with?
For eg: I saw a question that asked "A blue glass when heated will glow with which colour?" and the answer was stated as "yellow" because "Blue glass appears blue at ordinary temperature as it absorbs all ... |
Imagine a chain of mass m hanging from a table(not frictionless) which slips down the table. I want to calculate work done by friction. Obviously as it opposes slipping it should be negative. However while i solved it using integration my answer is positive. What am i missing?
|
Lately I have been looking at some electrostatic generators and their design. The Van de Graaf seems to be the most common. Because it is used also in particle accelerators, do people actually control how much charge the machine generates? If so, how? I know I can just reduce the motor speed and the machine will pump c... |
I've heard sometimes that in projectile motion you need to shoot things with a $\pi/4$ angle in order to get the maximum range, but why does that happen?
In this case I know that
$$x(t) = x_0+v_{0x}t$$
$$y(t) = y_0 +v_{0y}t - \frac12 g t^2$$
How do you conclude that is necessarily $\pi/4$?
|
From the binding energy per nucleon (B.E./A) vs atomic number (Z) we know that Iron (Fe) is most stable nuclei in the nature. Here comes the question that if nature has found the stable nuclei then why does it has nuclei in higher mass region?
|
I want to discuss derivation of Feynman-Heaviside formula.
The topic has already been discussed here but I can not put there any question that's why I'm making new post.
Deriving Heaviside-Feynman formula for the electric field of an arbitrarily moving charge from Lienard-Wiechert potential
Could anyone help me and exp... |
When a metal or rubber is bent and deformed, it heats up. What is the reason for this?
I know that when deforming it, work is done on the object. If the object is perfectly elastic, all of the energy is stored as elastic potential energy, which is released when the stress is removed. But if it not perfectly elastic, by... |
This is in relation to the scalar diffraction theory described in the Introduction to Fourier Optics by J. Goodman. A sufficient condition for Fresnel approximation to be valid is that the higher-order phase terms in the binomial expansion of the propagation distance can be ignored. However, I would like to know if Fre... |
This question arose when trying to reconcile the way in which the beta function is usually first introduced in the context of perturbative QFT with the statement that a vanishing beta function implies the underlying theory to be conformal. I assume that my confusion is due to my total lack of experience with conformal ... |
I understand it's possible to find pressure loss using formulas such as the Darcy Weisbach equation works with turbulence - but to my knowledge the friction factor is derived using empirical means.
Is there a purely math-based way to solve for pressure loss in turbulent flow along a uniform pipe (assuming the fluid is ... |
I have some question about work done. I understand the mathematical ways and examples which are floating all over on internet & books. But all these information not clearing the concepts of work done as well energy. Please clear following questions:
If there are other physical quantities available why work done is nee... |
In spherical coordinates, the eigenfunctions of the operator $\hat{L}^2$ can be obtained by solving the problem
$$
-\dfrac{\hbar^2}{\sin\theta}\dfrac{\partial}{\partial\theta}\left(\sin\theta\dfrac{\partial Y(\theta,\varphi)}{\partial\theta}\right) - \dfrac{\hbar^2}{\sin^2\theta}\dfrac{\partial^2 Y(\theta,\varphi)}{\pa... |
Suppose I have a many-body system with creation/annihilation operators $\hat{c}^\dagger_n$, $\hat{c}_n$, and Hamiltonian:
$$\hat{H}=\sum_n E_n \hat{c}^\dagger_n\hat{c}_n$$
If I wanted to write down the density matrix for a thermal state in the grand canonical ensemble with inverse temperature $\beta$ and chemical poten... |
So, I'm in high school and I've just been learning Quantum Mechanics. I'm trying to understand some concepts, since I'm interested in them, and I was having trouble resolving some doubts.
Namely, how exactly do constants undergo transformations? Say if I have the transformation;
$$
(\hbar, E)\longmapsto(\hbar+2\pi, E)
... |
I'm in year 10 (9th Grade for the Americans) and I just had a question about physics.
How does a battery create potential difference?
It it because the electrons are gaining energy as they get pulled further away from their atoms or it is becuase of the concentration of delocalised electrons at the negative terminal?
|
What causes the geometrical magnetoresistance effect? Sure, it is some kind of geometry but how/why? What is happening on the physical level that the resistance increases (or decreases?) with an applied magnetic field?
|
From when I first learned flux and till now, I was thinking of flux as a measure of 'flow'. Now, this interpretation breaks down if you consider conductors as I will show below.
Here, there is abrupt drop in flux as the the field passes through the conductor an abrupt increase outside. I don't understand how to reconc... |
We know that photons (light) are massless but they have momentum. Now suppose I am in the space far away from planets/stars that there is no external force exerts on me, if:
1- I turn on a flashlight (torch), would I be pushed in the opposite direction which the flashlight is facing (Newton's third law)?
2- If a star i... |
Suppose you have a positive charge fixed at a point in space.
Now introduce an infinitely large metal plate close to the charge.
Would there be electric field on the other side of the metal plate where there is no charge?
According to the superposition principle of electric fields, there must be an electric field (as t... |
I'm trying to self study Classical Mechanics and I got a question on it.
Assuming that an object (I will call it Alex and weights 1kg) is in space and there are no objects except Alex and there is no external force. So if I push Alex with a force of 1N for 10 seconds and then stop pushing, he will move with a constant ... |
In many books, while introducing Special relativity it is shown that Maxwell's equations are not consistent with Galilean transformations. So either Galilean transformations (and consequently Newton's Laws) are false or Maxwell's equations are false, and it turns out that Lorentz transformations are the more correct tr... |
The first law states that
$\text{d}Q = \text{d}W + \text{d}U$
where $\text{d}W$ is the work done by the system on the surroundings.
As far as I remember from my chemistry courses,first law in chemistry is
$\text{d}U= \text{d}Q + \text{d}W$
where $\text{d}W$ is the work done by the surroundings on the system.
My questi... |
Consider a situation as given in the picture:
Would introduction of the dielectric slab reduce the force of attraction a charge feels (towards the other charge)?
What if one of the charges is inside the slab, how would we find the force?
|
Is there a machine or instrument which will notify us instantly when the wave-function has collapsed if we have access to only one of the entangled particles? Note that the wave function collapse will be triggered by observing the particle which we do not have. Or in other words is there a way to identify (instantaneou... |
A perfectly inelastic collision is one where both of the colliding objects stick together and move as one.
My question is, why, of all possible combinations of final velocities that conserve momentum, does this one lead to the greatest loss in kinetic energy?
One reasoning I found was that this is the only combination ... |
While studying the representation theory, I came up with the following example, but it seems hard for me to solve.
For an integer or half-integer $j$, let $V_j$ be a $(2j+1)$-dimensional complex vector space with basis
$$\{{|j, j\rangle, |j, j-1\rangle, \cdots, |j,-j\rangle}\}$$
which transforms as an irreducible repre... |
In the paper cited below, a certain unknown function $g(E)$ is responsible for the generation of the fractal pattern observed in the band spectrum of the Hamiltonian of the system:
$$
H=e^{ix}+ e^{-ix}+e^{ip}+e^{-ip}
$$
in the transformation:
$$
(\hbar, E)\longmapsto (4{\pi}^2/{\hbar}, g(E))
$$
I have not been able to ... |
I know how to treat Feynman interactions without derivatives by Wick contraction. But now, take for example $$\mathcal{L}_{int}=\lambda \phi (\partial_{\mu}\phi)(\partial^{\mu}\phi).$$
Now many books write that in momentum space the derivatives turn into momenta. While I can imagine this happening, I don't really know ... |
Is there a machine or instrument which will notify us instantly when the wave-function has collapsed if we have access to only one of the entangled particles? Note that the wave function collapse will be triggered by observing the particle which we do not have. Or in other words is there a way to identify (instantaneou... |
Is the heat dissipated by a resistor given by $H = I^2RT$ or $H=(V^2/R)T$? In other words, if the resistance is reduced by a quarter, will the dissipated heat increase or decrease?
The two formulas give different answers for the example values, for current $I=3$, resistance $R=4$, voltage $V=12$ and time $T=1$.
Case 1... |
When solving the Schrodinger equation for a nucleus, e.g. infinite spherical well problem, the eigenfunctions are of the form $\Psi(r,θ,ϕ)=R(r)Y_{l,m}(θ,ϕ)$, where the $Y_{l,m}$'s are the usual spherical harmonics. From this, it can be shown that the radial equation solutions involve the spherical Bessel equations (The... |
After reading a comment below I edited the question to simplify it.
Imagine infinite beads on an infinite straight line, all at rest. The distance between all beads is finite. The mass of the first bead is $m_0 \lt \infty$. The relation between the masses of the beads: $m_j=Cm_i$, where $0\lt C \lt 1$.
We give the firs... |
I'm trying to understand and equation for serpentine locomotion. However, I'm having a little trouble understanding it.
$$ \Phi(t) = \alpha \sin(\omega t + (i-1)\beta) + \gamma $$
I know like $t$ is time and I'm guessing $\alpha$ and $\beta$ refer to angles but I'm having trouble understanding the rest.
Source: https:/... |
In David Tong's notes on quantum field theory, one of the problems asks to show that a tensor defined by
$$\Theta^{\mu\nu}=T^{\mu\nu}-F^{\rho\mu}\partial_\rho A^\nu$$
where $F^{\rho\mu}=\partial^\rho A^\mu - \partial^\mu A^\rho$ for the electromagnetic four-potential $A$, and $T^{\mu\nu}$ is the energy-momentum tensor ... |
Neamen's book states that the Fermi-Dirac distribution can be interpreted as the ratio of filled to total quantum states at any energy. For intrinsic materials, the value of Fermi-Dirac distribution at the Fermi level, which is in the middle of the conduction band and valence band, is 0.5. Does that mean quantum states... |
First I would like to remind Lorentz transformation of length and time as a matrix:
$$ \begin{pmatrix}
ct'\\
x'\\
y'\\
z'
\end{pmatrix} = \begin{pmatrix}
\gamma & - \frac{v}{c} \gamma & 0 & 0 \\
- \frac{v}{c} \gamma & \gamma & 0 & 0 \\
0 & 0 & 1 & 0 \\
0 & 0 & 0 & 1
\end{pmatrix} \cdot \begin{pmatrix} ct \\ x \\ y ... |
I'm trying to simplify an equation into a form that uses the ratio of the number density of sterile to active neutrinos.
For this, I need a relation between the time and temperature of the universe, the one I found was for during a radiation-dominated period and is (I don't recall where I got this equation from):
$$T= ... |
There is a innumerable number of questions on this site about black hole event horizons, the possibility of falling in and back out again, but none of them answer my question specifically.
I have read this question:
The confusion arises because it also has an external mathematical surface, called the ergosphere, where... |
The QCD Lagrangian for two flavors is:
$-\frac{1}{4} G\tilde{G}+i\bar{u}\displaystyle{\not} D u+i\bar{d} \displaystyle{\not} D d-m_u\bar{u} u-m_d\bar{d}d$
or alternaively
$-\frac{1}{4} G\tilde{G}+i\bar{u_L}\displaystyle{\not} D u_L+i\bar{d_R} \displaystyle{\not} D d_R-(m_u\bar{u_R} u_L+m_d\bar{d_R}d_L+ h.c.)$
where the... |
I'm trying to find how does this quantity $$\psi^\dagger\psi$$ transforms under a Lorentz transformation. Where $\psi$ is a Dirac spinor.
What I've tried so far:
It is known that a Dirac spinor transforms as $$\psi' = S\psi.$$ The matrix $S$ satisfy certain properties.
I calculated $\psi'^\dagger=\psi^\dagger S^\dagger... |
I would like to calculate the resistance in a resistor in a circuit with a $9V$ battery. I have no ammeter; only a potentiometer. I do know, however, that the $9V$ when hooked up from terminal to terminal with just the wires induces a certain current $I^*$ (So $\frac{9V}{I^*} = R_{wire}$).
Having connected the resistor... |
Suppose the coefficient of linear expansion is $\alpha$, [and is, independent of T]. Then,
$$\alpha=\dfrac{dV}{VdT}$$
Upon integration, this yields : $V=V_{0}e^{\alpha(T-T_{0})}$. Using the maclaurin series for $e^x$, we get:
$$V=V_{0}(1+\alpha(T-T_{0}) +{\alpha^2(T-T_{0})}^2....)$$
However , Most textbooks simply writ... |
Usually, it is mentioned that the Higgs field IS the origin of mass for known fundamental particles.
If very heavy dark particles are found (heavier or much heavier than the top quark), should it mean that there is OTHER mechanism responsible of the origin of Dark Matter particles, not the Higgs field we do know? After... |
Q. A thin biconvex lens is kept on a plane mirror. When an object is kept at $20 cm$ in front of the lens, its image is formed at the same point. The focal length of the convex lens is
The solution given is
$\frac{2}{20}=\frac{1}{v}-\frac{1}{u}$
and after putting the values we get $f=20cm $
My doubt is why that 2 above... |
My problem is somewhat general. I do not think it has been posted before, however, I am new to Physics Stack Exchange so please, if I'm wrong, feel free to let me know.
I will give an example problem and then talk about the general case I'm interested in.
Given the outer surface of a cylinder with height $l$ with a sur... |
Consider a fixed, positive Point charge $q1$, kept at the origin. Another (positive) charge, $q2$, is being brought from $\infty$ to the point $(r,0)$, by an external agent slowly. We wish to calculate the work done by the external agent (and thus derive the "potential" of the point charge $q1$, being defined as $w_{e... |
I am reading the book Nonequilibrium Statistical Mechanics by V. Balakrishnan. In chapter $17$ (page $244$) he argues that the original Langevin equation has inconsistencies and should, therefore, be replaced by generalized Langevin equation. He shows the inconsistency as follows (which I am not fully convinced about).... |
I read this answer to another question:
My indoor exercise cycle specifically cautions against using pedals
which are not designated as being strong enough for indoor cycles.
Supposedly, the stresses put on pedals on exercise bikes are greater
than those on real bikes.
It is not apparent to me why a stationary bike w... |
The following is my rough understanding of topological phases of matter (please let me know if it is incorrect.) Topologically ordered phases of matter are topological in the sense that they are determined by their topological excitations, and specifically by the braiding and fusion of these. The topological data that ... |
So, I understand that the magnetic domains in the weak magnet are realigning when exposed to the strong magnet. But what is it with the speed, like how does speed come into the picture?
P.S. This question was asked to me by a kid of 7th standard. He found this thing in his physical science textbook. I could explain to ... |
Wu's experiment shows that the mirror image of a system doesn't necessarily act the same as the original system. But the experiment only mirrors the position of every particle, not the particles themselves!
Wouldn't the logical conclusion be that quarks are not just points, but rather more complex structures that have ... |
Black holes can emit Hawking radiation. The larger the mass of a black hole the lower the frequency of emitted radiation (aka the temperature of the object). Hawking radiation of a large enough black hole is colder than CMB. In which case the flux of CMB energy onto black hole should exceed the flux of energy from blac... |
If you place a dipole at the center of a conducting, non-grounded, spherical shell, the electric field outside the shell is zero. However, if there is a point charge in the center, there is an electric field outside.
I understand that the net charge in the system is zero, because of the dipole, and then maybe it's a vi... |
I am currently working on understanding the (intrinsic) differential geometry underpinning General Relativity, and I think I could benefit from a more intuitive grasp of the process of taking the Lie derivative of a vector field with respect to another vector field.
I ask this question for this reason. Pictorially, I u... |
Consider a plate $P$ of thickness $d$ (for example a plate of wood) laying on a hard surface $S$ (for example on concrete floor). Suppose you have a maximum value of pressure $p_{\mathrm{max}}$ $S$ could tolerate before it fails in some way. Suppose further you know a pressure distribution acting on plate $P$ downwards... |
Maybe it is easy but I am fairly confused. If a bubble of gass is 1m deep in the sea when left go will move up due to gravity pulling down havier water molecules. All is explained by the law of difference in pressure but in the case of Earth's gravity closer to the Earth's center gravity starts disapearing and at the v... |
I am trying to optimize the acoustics of a room in my house for music listening. I use a computer that runs a free app called, REW (room Equalization Wizard) . This app can play a test noise through my speakers and simaltaneously record the resulting output and echoes through a calibrated microphone attached to one of... |
Classically, a system of noninteracting electrons restricted to move in 2D will execute circular motion in an external magnetic field $\perp$ to the plane. But in quantum analysis, the same noninteracting electrons in the same situation gives rise to equispaced harmonic oscillator levels, called Landau levels. Why shou... |
For a torque free symmetric top, is the angular momentum in body fixed coordinates in same direction as instantaneous axis of rotation?
I know that instantaneous axis of rotation precesses about symmetry axis, and Goldstein says that the angular momentum of the torque free symmetrical top rotates in body coordinates ab... |
Does there exist an exact metric in the literature for embedding the Schwarzschild metric in the Friedmann–Lemaître–Robertson–Walker metric? If so, please give a good reference. Thanks.
|
If you flip the sign of the term containing the field strength tensor (e.g. change $-\frac{1}{4}F^{\alpha \beta}F_{\alpha \beta}$ to its negative) in the Lagrangian for electromagnetism, you get a theory where like charges attract and opposite charges repel instead of the other way around. Imagining a universe where on... |
I am new to learning about the concept about the collision cross section. I am having a hard time understanding the collision cross section (defined as $\sigma_{AB}=\pi(r_A+r_B)^2$ in this link ).
But then the verbal definition of collision cross section is "an "effective area" that quantifies the likelihood of a scatt... |
I heard once that with a special crystal it's possible to "convert" somehow two green photons to a ultraviolet one and that some UV-lasers are based on this fact. Is this right, and even more important: Does anyone have a keyword I can use for some additional research? My (german-language-based) research only led to... |
Given some total system $ H = H_A \otimes H_B$, we can find the entanglement entropy for a subspace by taking $S = -tr(\rho_A ln \rho_A)$ with $\rho_A = tr_B \rho$, where $\rho$ is the density matrix of the system. For a two particles in a two level system (i.e. a state can be in $|0 \rangle$ or $|1 \rangle$, this seem... |
I've been working on my dynamics homework when I've run into confusion with derivatives and could use some help regarding that. The question is as follows:
When varying a functional with respect to a variable, do we consider different derivatives of functions to be independent? For instance, what is the functional deri... |
We know in the infinite square well that the general solution is a linear combination of the stationary states ( states with definite energy eigenvalues). Also the measurement of the energy for that wave function at any time would yield one of those eigenvalues, with some certain probability. My question is: What is th... |
Lets suppose a proton is brought from infinity towards another proton which is fixed, now we can easily calculate the Work done by the external force and we can calculate the potential energy of the proton by question was that is this the potential energy of the system or only of the proton and please give a reason.
|
Let the voltage source , transformers(generally) , be called 'T'.
Let the electric device (drawing current from the transformer) be called 'D'.
Now the domestic circuit is a closed circuit consisting of Live, neutral and earth wires.
Live wire ---> Carries current from T to D ---> around 200V(Different for different co... |
To provide context for the title, is it possible that dark matter is just gravity from other 'branches' of the universal wave function that have split from ours, that are weakly interacting with the gravity in our branch? Is this an idea anyone has explored before?
|
Einstein in his book: Relativity: The Special and General Theory.
http://www.ibiblio.org/ebooks/Einstein/Einstein_Relativity.pdf
[edit] on page 56, I believe]
writes, "the expression for energy" in the form $\frac{mc^2 +E_0}{\sqrt{ 1-v^2/c^2}}$,
where $m$ is the rest mass and $mc^2$ the energy of the rest mass.
$E_0$ ... |
Can the difference of specific heat capacity of water under isochoric and isobaric conditions be explained in terms of the internal energy of the system? Most of the videos I have watched base their explanation in terms of ideal gases. I guess its something to do with the fact isochoric conditions mean all the heat ene... |
Would it be possible to measure energy directly in joules instead of measuring what effect energy has on something?
Say for example you have a car of known weight traveling a speed v. To get the car's energy we would have to measure its weight and speed, not its energy directly. Same with a calorimeter, we have to meas... |
I was going thorough paper Transformation of quantum states using uniformly controlled rotation by Mottonen et al. In that it says
The configuration space of the $n$-qubit quantum register is $2^n$-dimensional complex space. Excluding the global phase and state normalization, we find that the general unitary transform... |
Not as popular as the Copenhagen interpretation perhaps, but I'm truly intrigues to know the intricacies of the de Broglie-Bohm Theory. However, I could find absolutely no source which could teach me the same (unlike the innumerous texts on Copenhagen Interpretation). Does anyone have any idea where it can be studied f... |
How can you determine if a process is possible or impossible by using the 1st and the 2nd Laws of Thermodynamics?
|
In the book 'OPTICS' by Eugene Hetch it is written that, "the optic axis is actually a direction and not merely a single line".
I can't understand why it is a direction, not a single line?
|
What is superradiance? I came across this term recently (used widely to explain fast radio bursts). After googling a bit, what I understand is:
When several atoms are confined in a very small area and one of the atoms emits a photon (spontaneously and randomly), it affects all other excited atoms in its neighborhood to... |
Let's consider a liquid that contains either dextrogyre or levogyre molecules, but only a highly preponderance of one of them.
Since the molecules are randomly oriented in the liquid, how is it possible to have a net rotation power of the liquid since the various angular orientations of the molecules should cancel out ... |
How to distinguish the $p_x$, $p_y$, $p_z$ orbitals since one could choose the $x-$, $y-$ and $z-$axes arbitrary?
How could the can the wavefunctions that describe the probability of the presence of electrons in the associated orbitals have a physical meaning? One could decide to make any arbitrary tiny 3D rotations so... |
I often see in physics that, we say that we can multiply infinitesimals to use chain rule. For example,
$$ \frac{dv}{dt} = \frac{dv}{dx} \cdot v(t)$$
But, what bothers me about this is that it raises some serious existence questions for me; when we say that we take the derivative of $v$ velocity with respect to distanc... |
The usual definition of heat capacity $C$ is that when we put a certain amount of heat $dQ $, the temperature will rise by $CdT$. But why is it a constant?
In better terms why is heat strictly proportional to the temperature, with nothing else intervening in the formula .
Was it an experimental discovery or is there so... |
Is there any way to theoretically obtain values of specific volume, internal energy, enthalpy and entropy of air, assuming it's an ideal gas?
Can it be done using ideal gas laws?
|
As the voltage is applied at both sides of the dielectric material(ex. front surface +5V and rear surface 0V), the energy is stored in the material, right?
I heard it's because the dielectric molecules slightly rotate due to the electric field. If so, does the dielectric constant of the material also differ from the on... |
So recently I've been doing some self-study on canonical transformations and relating together different Hamiltonian systems.
I've found this paper (PDF) with a remarkable result showing that any two Hamiltonian systems $H(q,p)$ and $K(Q,P)$ with the same degrees freedom, are locally equivalent and connected via specif... |
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