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I have heard that the mass of a particle can't be negative because the hamiltonian should be bounded from below. What is the formal argument regarding this and why the same argument doesn't follow when we are talking about charges?
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For say, what would be the difference between two capacitors with the same capacitance only one storing 0.5 joules and the other one 1 joule.
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In this page explaining the foundation of the Lagrangian mechanics, we can see that starting at:
$$ m \left[ \frac {d} {dt} \left( \frac {d \mathbf{r}} {dt} \delta \mathbf{r} \right) - \frac {d \mathbf{r}} {dt} \frac {d \delta \mathbf{r}} {dt} \right] $$
it is possible to obtain:
$$ m \sum_{k} \left[ \frac {d} {dt} \le... |
I've been recently learning about numerical methods in physics, and have come across matrix product states and tensor networks. This is definitely a vague question, but I was wondering if anyone knew of any places where I could find code examples (or pseudocode examples) for simple systems like the Ising Model, (low si... |
I have this general state $\lvert \psi \rangle_{AB} = \sum_{\alpha\beta}c_{\alpha\beta}\lvert\alpha \rangle \otimes \lvert \beta\rangle$ of two qbits. I want to write the state of the system after the measurement. The measurement is performed only on the first qbit. Let's say that the value found was $\alpha_1$, I wrot... |
What do we mean when we say that we have a probabilistic theory of some phenomenon?
Of course, we know from experience that probabilistic theories "work", in the sense that they can (somehow) be used to make predictions about the world, they can be considered to be refuted under appropriate circumstances and they gener... |
I have been asked to decompose the state $|\Psi \rangle$, with wavefunction in spherical coordinates $\langle r \, \theta \, \phi|\Psi \rangle = \sqrt{\frac{3}{\pi}}e^{-r}\sin{\theta}\cos{\phi}$ into the $|L = 1 \, m_z\rangle$ basis.
I know $\langle \theta \, \phi|\ell \, m\rangle = Y^m_\ell(\theta, \phi)$, and $\Psi(r... |
Since the electric and magnetic fields are produced by charged particles, is it correct to think that light travels trough a medium consisting in this particle-antiparticle pairs from vacuum polarization?
If so does that mean that light doesn't really travel in vacuum, but rather is the byproduct of the interactions b... |
Should density of states for electrons always be symmetric?
The Hamiltonian I am considering is:
$$
H= \Sigma_{<i,j>,\sigma} -t(C^{\dagger}_{i\sigma}C_{j\sigma}+ C^{\dagger}_{j\sigma}C_{i\sigma})+ J_H\Sigma_{i} \vec{S_i}\dot{C^{\dagger}_{i\alpha}\vec{\sigma_{\alpha\beta}}C_{i\beta}}
$$
where $ \vec{S_i} $ is an underly... |
I know Faraday-Newmann-Lenz's law is...(easy form)
$$\mathcal E_{\text{inducted}}=-\frac{d\Phi_S(\mathbf{B})}{dt} \tag 1$$
The flow through a Gaussian surface is given by a surface integral through $S$,
$$\Phi_S(\mathbf{B})\equiv\int_S \mathbf{B} \cdot d\mathbf{a}$$
Why the relation
$$\boxed{\frac{dB(t)}{dt}=-kI(t)} \t... |
Is there an equivalent non vacuum medium of propagation for GW's?
Can GW's be absorved or damped? Reflected?
Can we perform a double slit experiment on GW's?
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I have a very naive question.
Suppose you have pure water in a flask, and you place two ends of a copper wire (which are connected to a battery) into the water.
If you were to place your hand into the water, you would not feel any shock, as pure water does not conduct electricity.
However, if you add an electrolyte lik... |
Given, for instance, the perfect fluid energy-momentum tensor:
$$T_{\mu\nu} = (\rho+p)u_{\mu}u_{\nu} - pg_{\mu\nu}\tag{1}$$
We can put (due to diagonalization procedure) into the diagonal for as:
$$T_{\hat{\mu}\hat{\nu}} = Diag[\rho, \tau,p_{2},p_{3}] \tag{2}$$
On the other hand , if we specify a tetrad frame we write... |
While an object is still in the air falling under the influence of gravity, does it take greater force to push or steer it to the side compared to when the object is in a state of rest?
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This one, I hope, is pretty simple. I'm working on a school project that's looking at the feasibility of a methane fueled rocket motor. Right now I'm looking at regenerative cooling for the nozzle itself and found the following paper that seemed to give one of the better descriptions on the design and function of re... |
Suppose I am throwing horizzontally a ball with mass "m" against a wall (whose mass and stiffness can be assumed to be infinite).
I accelerate the ball with a constant force "F" along a distance "s" before letting go. So, calling ""$v_f$" the final velocity of the ball, I can write (work - energy theorem):
$$F\cdot s =... |
In order to establish an arc in a low voltage, high current suruation such as welding, why do the wires or electrodes need to touch, then pull away to establish an arc?
Why would this arc not be established when the electrodes were brought close to one another initially?
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I saw that the two end wires of a capacitor when touched to each other neutralizes quite fast(as the flash after their contact was there only for a second), how can charges neutralize the capacitor so fast?
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I hope this is an okay place to ask this. Not a lot of places for amateurs to seek guidance for failed experiments or rudimentary knowledge.
This was an experiment I just tried, and want to understand why it didn't work.
I understand that moving a magnet through a copper coil will generate a magnetic field.
And my very... |
I'm trying to find the normal models of a particle with charge $q$ and mass $m$ in a
$3$-dimensional harmonic oscillator potential with an applied uniform magnetic field $B=B_0 \hat{z}$. The potential has a natural frequency $\omega_0$. The Lagrangian is therefore
$$L = \frac{1}{2}m(\dot{x}^2 + \dot{y}^2 + \dot{z}^2) -... |
My question is very similar to this one: Radius of curvature.
The only difference is that in this case instead of a known curvature y, we have points x and y on a cartesian coordinate system that define a curve.
How does one calculate the radius of the curvature in this case?
|
I have applied amperes circuital law to an infinite wire. But if I apply the same rule to a finite wire then also the condition will be same. In a circular path of some radial distance from wire field will be same and direction of field at every pointon the amperian circukar loop will be parallel to the loop direction... |
I am currently studying Introductory Semiconductor Device Physics by Parker. Chapter 2.5 The concept of effective mass says the following:
Figure 2.8 shows two hypothetical energy-momentum diagrams for an indirect and a direct band-gap semiconductor. We can gain a lot of information about the hypothetical semiconducto... |
Variants of this question have been asked before, and techniques for deriving all 8 eigenstates of the total system have been provided, most clearly in this post: Adding 3 electron spins
My question is about what arguments can be made if one is given a series of states, such as,
$$\frac{1}{\sqrt{2}}(|↑↓↑⟩-|↓↑↑⟩)$$
$$\f... |
Initially suppose, there is no dielectric object(brown rectangle) present in capacitor. The charge density on left plate is +σ and on right plate -σ. It is clear that electric field due to both plates is σ/ε in right direction in between capacitor.
Now, place a dielectric object as shown in Fig. partially. The dielec... |
I know that quantum computers have a extremely large capacity to do many different calculations at once, but how many different calculations? Is it infinite, like I've heard some articles say, or is it the number of Qubits in a given quantum computer, or is it linked in some other way to the number of Qubits?
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I am currently studying Introductory Semiconductor Device Physics by Parker. Chapter 2.5 The concept of effective mass gives the following example:
For GaAs, calculate the typical (band-gap) photon energy and momentum, and compare this with a typical phonon energy and momentum that might be expected with this material... |
Ampere's law is used to find the magnetic field B in a solenoid but not in a circular current loop. Take infinitesimal current elements on a circular loop, applying Ampere's law and summing up the B yields a different B as obtained by Biot Savart. However, in a solenoid, finite current wires are allowed in the applicat... |
Suppose that you irradiate a beam of monoenergetic alpha particles on a target. You can determine the saturation activity using
Saturation activity = $\frac{R_a x \sigma \rho N_A}{A}$
But how do you determine the activity after say half-an-hour of irradiation?
What is confusing me about this is that a radioactive isoto... |
I recently came across the article The Quantum Internet Is Emerging, One Experiment at a Time in Scientific American where it was discussed how quantum networks could provide a level of privacy and security impossible to achieve with classical networks.
To quote from the article:
Although a fully realized quantum netw... |
While studying the Capacitors, I read and understood that the Energy stored in a Capacitor which is given by (1/2)Q V.
The next topic was the Energy density and the book stated
that the energy stored in a Capacitor is electrostatic potential energy.
When we pull the plates of a capacitor apart, we have to do work again... |
I bumped into this:
Can a shadow move faster than the speed of light?
while trying to see if I could find out anything about what I'd been thinking for 2 years now.
Bear with me here, cause I'm only gonna copy-paste what I'd written at another location where no one bothered to answer because... Well... I guess no one's... |
The shell of a space station is a blackened sphere in which a temperature $T = 500 K$ is maintained due to the operation of the appliances of the station which always supply heat at constant rate. If the station is enveloped by a thin spherical black screen of nearly the same radius as the radius of the shell of the s... |
I have recently learned about the equivalence principle and what it says is that( If I have understood it properly) the trajectory of the particles will be the same irrespective of the properties of the particles if the initial conditions are the same. My book says due to this principle we can change our transformation... |
The standard way to derive the non-relativistic limit and its corrections in general relativity is to formally expand Einstein equation in powers of $1/c$ around a background space-time. The non-relativistic approximation implies weak fields as well since otherwise the particles would accelerate and acquire relativisti... |
Currently I am going over explicit symmetry breaking in chiral Lagrangians. In particular, consider a term
\begin{equation}
\mathcal{L}_{\text{mass}} = \bar{Q}MQ
\end{equation}
where $Q = (u, d)^T$ and
\begin{equation}
M =
\begin{pmatrix}
m_u & 0\\
0 & m_d
\end{pmatrix}
.
\end{equation}
Following some course notes, we ... |
Consider the problem of a classical pendulum whose state can be described by a function $\theta(t)$ where $\theta$ is measured from the line directly below. We then have that our pendulum's $\theta$ obeys the following differential equation
$$ \frac{d^2 \theta}{dt^2 } + \frac{g}{l}\sin \theta = 0 $$
Through the trick ... |
I do have some problem in applying Newton's Second to systems with variable mass.
This is what I understand:
Mathematically, the law states that:
$$F=\frac{dp}{dt}=m\frac{dv}{dt} + v\frac{dm}{dt}$$
where $F$ is the net external force "on the system" and $\frac{dp}{dt}$ is the
rate of change of momentum "of the system"... |
I am looking to study cosmology at graduate level. Does any one recommend any introductory and comprehensive books for cosmology principles? I am interested in the maths too but I really want a book that introduces the principles and concepts first, to then dig deeper with the maths later.
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I drew a mechanical model of a marching band analogy of refraction of a wave front using the concepts of a geometric/trigonometric proof of Snell's Law. The drawing is attached to this question. I have drawn three conditions for wave fronts on the opposite side of the interface (solid blue dot if $v_2 < v_1$, red if ... |
I'm trying to understand the non-perturbative picture of anomaly inflow, mainly following these two articles by Witten and Yonekura:
[1] - https://arxiv.org/pdf/1909.08775.pdf ,
[2] - https://arxiv.org/pdf/1607.01873.pdf .
Let's start from the basic case when we consider a massive fermion in a d+1-dimensional manifol... |
In the book Principles of Physics by Resnick Halliday:
The decrease in Potential energy of a parallel plate capacitor due to a dielectric is because the slab would start to oscillate and the energy would transfer back and forth between the kinetic energy of the moving slab and potential energy stored in the electric fi... |
I read about Bose-Einstein condensate consist of bosonic atoms at incredible low temperature do not obey Pauli exclusion, I am wondering what happens if it is possible to create fermionic photon for example so it obeys Pauli exclusion principle?
|
For any continuum, fluid or solid, we can express mass conservation through the continuity equation
$$\frac{\partial \rho}{\partial t} + \nabla \cdot (\rho \mathbf{v}) = 0 ,$$
where $\rho$ is density and $\mathbf{v}$ is velocity. We can also express momentum conservation through the Cauchy momentum equation
$$\frac{\pa... |
I have referred several sources which derived the equation for the power transmitted along a string by a sine wave.
However, I could not find anywhere what exactly is it?
"Along a string" makes me think that energy is transmitted from one part of the string to the other, but I find myself unable to form a well defin... |
Consider the figures I and II
, they consist of similar circuits with identical batteries. There are two different slabs connected in the circuit, both are geometrically identical and have the same conductivity $\sigma_1$, but have different dielectric constants $k_1$ and $k_2$ respectively, will yhe electric field i... |
My teacher was teaching us about the process radiation in heat transfer. He told us there are
Perfectly absorbing surface i.e. Black body.
Perfectly reflecting surface.
Then I asked him about perfectly transmitting surface. But he answered it doesn't exist . Can anybody tell me why it doesn't exist?
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Suppose a inclined plane
Now in normal projectile problem we can normally apply energy conservation laws but in this case since this is a inclined plane we have to transform the conservation laws now this sounds confusing but i am saying that suppose a ball is thrown from one end of inclined plane and it reaches the o... |
dipole in chemistry has a direction in the flow of electron i.e. from positive to negative whereas in physics it is from negative to position why ?
|
I am trying to compute the work needed to push air through a fabric filter. The only variable I know is the Pressure drop across the filter.
From what I gathered (mainly through online searches), the work is calculated by multiplying P and V, but I'm not sure that multiplying the pressure drop (known variable) and the ... |
Could you give me two experiment results that are consisitent with the prediction of general relativity, but inconsistent with the prediction of special relativity + Newton’s law of Gravitation ?
|
I have this question where in which the integrals are made from a volume to the integral only dependent on the radial distance R.
While they prove this in part b) of the answer in part a) they somehow arrive to the same results.
|
You are isolated ( no bodies around you except the wheel) .
Now you(orange) spin the blue wheel ( torus) with an $\omega$ in the direction of axis and then let go of the wheel . Now how will you move ? Will you keep moving in the brown circle ? ( Because by conservation of angular momentum you must also have an opposi... |
I know that Planck has measured the baryon density, $\Omega_B$, as a fraction of the critical density, $\rho_{CRIT}$. Is there a measurement of baryon density that's independent of the critical mass and the $\lambda CDM$ model that one can use as a sanity check?
|
Assume I have an action defined as
$$
S[g]=R[t,x,y,z]\sqrt{-|g|}
$$
By variational principle, I get
$$
\delta S[g]=\frac{\delta (R[t,x,y,z]\sqrt{-|g|})}{\delta g}\delta g
$$
which gives the Einstein field equations.
If I use the Lagrangian:
$$
S[g]=\int R[t,x,y,z]\sqrt{-|g|} dxdydzdt
$$
By variational principle, I get... |
Are there any limits to the frequencies for which laser frequency doubling (or multiplying) can be applied? For example, is it possible to convert a far infrared or microwave laser/maser to ultraviolet or x-ray by using multiple frequency doublers/multipliers in series?
|
I am wondering if there is a platform to which researchers share or publish the code they used in their research. I noticed that many researchers explain their algorithm and math and present the results visually but the actual program they used are not included in their papers.
For example, on page 262 of 1, Section 3.... |
I'm writing a simple game, but as you can already see I'm far from being a physicist of any kind. I have a system that calculates and draws orbit of a body with a given orbital speed and distance from parent body (Sun) at starting position. It's starting velocity vector is always perpendicular to the direction to the p... |
It doesn't make sense that a fine Iron wires have more surface area than an iron pan. How is it possible mathematically?
|
I want to know if capacitors connected in DC circuits having any combination of capacitors and resistors ever reach a steady state(no current flows through the capacitor) If that is the case then how can we prove it for the general case ?
|
I have a very rudimentary understanding of electromagnetic radiation and how it corresponds to temperature.
It is my understanding that any object above absolute zero first starts emitting radiation in infrared, and then as its temperature increases, it starts emitting in visible light from red to orange to white to bl... |
What is the gravitational wave luminosity of a rocket with mass $m$ (kg) accelerating at $\Delta v$ (m/s$^2$)? Intuitively, I expect the luminosity (in Watt) to depend on the mass and acceleration. Bonus question: What is the frequency of the emitted GWs?
Context: Gravitational waves (GWs) are generated by accelerated ... |
I'm studying how to calculate the density of states in the final configuration in order to apply Fermi golden rule.
For free EM field the following expression is the starting point:
$$d^3n=\frac V {(2\pi\hbar)^3}d^3P$$
while for non-zero mass particle this expression is the starting point:
$$d^3n=\frac V {(2\pi\hbar)^3... |
I am currently studying topological insulators and repeatedly found the claim (e.g. here), that the "basic hamiltonian" of a topological system in $d$ spatial dimensions can be written using the elementary representation matrices of a Clifford algebra
$$
H(\vec{k}) = \vec{h}(\vec{k}) \cdot \vec{\gamma} = \sum_{i=0}^d h... |
If a block is sliding down an incline it means the Normal force is acting at a point $x$ distance from the middle of the bottom of the base to produce an anti-torque to keep the body in rotational equilibrium. Now my question is will kinetic friction act at the point normal acts, or at the far end of the block? And whi... |
If I take a hose and cut it at the middle along its width (=horizontal cross-section), but I don't cut it completely into to parts, but around half of it remain connected, in a way it's difficult to determine by eyes sight if it's exactly half or not while I need it exactly in the half.
The issue is that I need a primi... |
Deriving de Broglie's equation (as per my text and teacher) involves equating $E = mc^2$ with $E = h\nu$, where $\nu$ is the frequency.
It goes like :
$$mc^2 = h\nu$$
$$mc^2 = \frac{hc}{\lambda}$$
$$mc = \frac{h}{\lambda}.$$
Then we replace $c$ with the velocity of the particle to apply it generally
i.e. $$mv = \frac{h... |
I think that it is impossible to have the permittivity in vacuum because of there is no matter. But, in Coulomb's law, the Coulomb constant(1/4πε) have ε which means the permittivity in a vacuum. How is it possible?
edit- The permittivity is a measure of the electric polarizability of a dielectric. A material with high... |
From what I've read, the cause for the force acting as the result of the Magnus effect is the formation of a bended wake behind the moving sphere.
Take a look at that picture:
(source: jschetz at www.dept.aoe.vt.edu)
From that picture, it appears to me that since the pressure gradient is directed into the wake region,... |
Let us say that we have a well-behaved fluid in all space (with speed of sound $c_0$ and density $\rho_0$). And I manage to compress it such that the pressure $p(\vec{r},t)$ at $t=0$ is given by
$p(\vec{r},t=0) = A \exp( -|\vec{r}|^2 / \sigma^2 ) + p_0$.
If we now let the system evolve freely, how can I calculate the s... |
Consider a water pump pushing water through a pipe:
We wish to find the energy which the water pump has to expend to keep the water flowing through the pipe. Writing Newton's second law for water flowing out of a cylindrical cross section of it,
$$ F= v \frac{dm}{dt}$$
Now, $$ P = F \cdot v$$
$$ P= v \frac{dm}{dt} v$$... |
According to wikipedia page of velocity:
The scalar absolute value (magnitude) of velocity is called speed
and according to wikipedia page of acceleration:
Accelerations are vector quantities (in that they have magnitude and direction)
thus I am wondering,
How is called the magnitude of acceleration?
|
So i'm currently researching nuclear power and nuclear energy as it is a topic that has always interested me, but when researching nuclear fission waste, and hearing about waste that has a half life of 1000s of years, I cant help but wonder, if a nuclear material is dangerous because of its emission when an atom decays... |
I know that charging a capacitor only moves particles from one plate to the other, so the total amount of charge in the capacitor does not change, nor does the total number of particles.
However, the charged capacitor does have electrical energy that the uncharged capacitor does not have, and energy has a mass equivale... |
Assume we are dealing wth three spatial dimensions $d=3$ which requires 3 $\alpha$ matrices. Furthermore assume that we are looking for them in the space of 4-dimensional matrices, not in higher dimensions.
I assume there are still different choices, which all fulfill the necessary commutator relations
$$\{\alpha_i,\al... |
I was reading about identical particles and i came across this example:
Consider two electrons with spin 1/2.
The Hamiltonian for this system is:
$$Η=\frac{p_1^2}{2m}+\frac{p_2^2}{2m}+\frac{1}{2}m\omega x_1^2+\frac{1}{2}m\omega x_2^2+g\vec{S_1}\cdot\vec{S_2}(x_1-x_2)^2$$
Im not sure what the last term means exactly, ... |
In the solution of the Killing equations for Schwarzschild metric, $\nabla_\mu\xi_\nu+\nabla_\nu\xi_\mu=0$ for rotational part of symmetry participate Christoffel symbols with purely angular coordinates.
$$
0=\nabla_{(\theta}\xi_{\theta)}=\partial_\theta\xi_\theta-\Gamma^\mu_{\theta\theta}\xi_\mu=\partial_\theta\xi_\th... |
I'm a bit confused about the statements in the following text:
If the autocorrelation function [$\xi$] describes the probability of a galaxy at a distance $r$ from another galaxy, the matter power spectrum [$P(\mathbf{k},t)$] decomposes this probability into characteristic lengths, $k\approx 2\pi/L$, and its amplitude... |
I remember hearing someone say "almost infinite" in this YouTube video. At 1:23, he says that "almost infinite" pieces of vertical lines are placed along $X$ length.
As someone who hasn't studied very much math, "almost infinite" sounds like nonsense. Either something ends or it doesn't, there really isn't a spectrum o... |
Let's consider the following theory:
$$L= -\frac{1}{4}F_{\mu \nu}F^{\mu\nu} +{1\over 2} |D_\mu \Phi|^2 +{1\over 2}|D_\mu \chi|^2 + \lambda_1\bigl(|\Phi|^2-\frac{v_1^2}{2}\bigr) +\lambda_2\bigl(|\chi|^2-\frac{v_2^2}{2}\bigr)$$
where $\Phi$ and $\chi$ are complex scalars coupled to a $U(1)$ gauge boson $A_\mu$ through th... |
The basis of classical QM is the postulate of a time evolution operator
$$|\alpha,t_0;t\rangle=U(t,t')|\alpha,t_0;t'\rangle$$
Is it correct to interpret this postulate as
All future states are determined by the presence, the past is irrelevant.
And infer that the first try to achieve a relativistic QM with the Klein-... |
What properties or quantities of two strings are considered when computing the interaction between them?
Is there a conventional way to represent interaction of two strings diagramatically? Or even better in form of an equation that takes a defined number of strings as input?
|
I have been trying to understand how a quadcopter yaws. Referring to the figure below which is bird's eye view of a quadcopter:
image credit : https://www.youtube.com/watch?v=iQAPkN7OWus
While the quadcopter is just hovering, the net angular momentum of the system is zero, since the angular momentums of motor set A an... |
In elementary QM courses we always consider that components of momentum vector form a complete set of commuting observables.
I am confused whether this is an input to our theory or whether we somehow derive this? As far as I can recall we take this as an intuition that the components of momentum vector will form a comp... |
As said in the title, I am curious about the reported measurements for cooled black bodies. Any source is welcome.
I am neither interested in any thought experiment nor in the well-established law of blackbody radiation accentuated on hot bodies.
|
When dropping several ice cubes into a full glass of water, I've noticed that the pitch of the cubes hitting against the side of the glass is much lower than if the glass contains less water - the less liquid is in the glass, the higher pitched the ice cubes sound when hitting against the side. Why is this the case?
|
It is often said and used that we can describe the state of a free spinless particle by just it's momentum.
Is the motivation for such statements coming from Hamiltonian formulation of dynamics? In which we describe a system using its Hamiltonian and if the system is free then, of course, momentum is sufficient to desc... |
I am currently studying Introductory Semiconductor Device Physics by Parker. Chapter 2.5 The concept of effective mass describes the light-hole and heavy-hole valence band in figure 2.8(b):
The author then poses the question: Which is which?
Since we have that $m^* = \dfrac{\hbar^2}{d^2E/dk^2}$, where $m^*$ is the e... |
So the question is clear from the title itself.
Only sometimes does the moon when it just rises above the horizon, looks reddish in colour. This mostly as I have seen occurs when the moon rises when it has gotten already a bit dark. When the moon rises in the evening, when there is still a bit of sunlight, the moon lo... |
The conductors of this experiment claim that causality is broken or at least made fuzzy by quantum mechanics. Is this really the case?
|
One way of deal with scattering problems is to use partial wave analysis.
This is the procedure I've found in my notes:
It's assumed that the observer is in the center-of-mass reference frame and the system is treated using the reduced mass.
When the interaction potential in the origin is zero the wave function is a pl... |
Do solutions to the Euler Lagrange equation for physical Lagrangians actually minimize the action? In other words, is it known that for all Lagrangians used in application, that the unique solution to the Euler Lagrange equation subject to initial conditions actually is a global minimum for the action functional? How a... |
Is a particle in between an entangled pair of two other particles affected if a measurenent is done on one of the entangled particles?
In other words. Do we know nothing happens in the space between the entangled particles?
|
Usually, in the context of non-equilibrium thermodynamics, it is said that entropy achieves a maximum in equilibrium, so the Taylor series expansion of entropy around the equilibrium state as a function of fluctuations $\xi_i$ of internal extensive variables does not have degree 1 (linear) terms, just the contributions... |
In the MTZ paper "Exact black hole solution with a minimally coupled scalar field" by
Martinez, Troncoso, & Zanelli, the scalar hair field is given by
$$\phi(r)=\sqrt{\frac{3}{4\pi G_N}}\textrm{arctanh}\left(\frac{G_N \mu}{r+G_N\mu}\right) $$
This can be solved from the potential ansantz
$$V(\phi)=-\frac{3}{4\pi G\ell... |
Since a geodesic is understood to be a map $\gamma : \text{real number interval} \rightarrow \text{spacetime } \mathcal S$, with certain additional properties, the image of a particular geodesic is some particular subset of spacetime, i.e. some particular set of events $\mathcal C_{\gamma} \subset \mathcal S$.
The geod... |
The concept, as explained in wikipedia is more or less clear to me. But the page is not very detailed. How does CCC works?
Also in another question, someone answered
Keep in mind that CCC is a dead theory. It became clear by 2010 that it was not viable because it made predictions about particle physics that were not c... |
Transformations of scalar fields under a Lorentz group transformation are generated by differential operators $L_{\mu\nu}=x_\mu\partial_\nu-x_\nu\partial_\mu$.
On the other hand, a representation of a Lie group $G$ and algebra is defined as a homomorphism $\pi: g\in G \rightarrow \pi(g)\in GL(n,\mathbb{C})$ and $\psi:... |
I have a problem understanding the phase space volume of entropy in the following example:
To make it easy let's say we have a system with one dimension, two particles & and a rough discretisation of the impulse values. Let the total value of the absolute impulses be $2$. so in regard to the impulses we have a certain ... |
Disclaimer: I am not a physics expert, just a teen with an interest.
I was watching a SciShow video, and they were talking about left-handed and right-handed neutrinos. The idea is that right-handed neutrinos are hundreds of millions of times heavier than the left-handed ones. So my question is, is it possible right-ha... |
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