QED explanation of entanglement]]>

A covariant tensor is like a gradient, as its units increase when the coordinate units do. A contravariant tensor's components decrease when the...

Units if conversion between covariant/contravariant tensors]]>

One more problem

View attachment 92570

Find the equivalent capacitance between A and B.

Equivalent capacitance, circular arrangement]]>

Five capacitors ,each of capacitance value C are connected as shown in the figure.The ratio of capacitance between P and R,and the capacitance between P and Q is

View attachment 92640

For...

Equivalent capacitance:pentagon shape]]>

In this article of Anton Zeilinger et al. they perform an experiment which suggests FTL or retrocausal influence.

Alice and Bob both produce their own...

Bell-state entanglement swapping and retrocausality]]>

I'm trying to understand the argument between eqns 4.117 and 4.119 in this paper http://arxiv.org/abs/1501.06570 as to why the penrose process is not possible for a boosted black string.

I understand the basic idea is to show using an argument similar to 4.33 that [tex]|E| <...

Ergoregions and Energy Extraction]]>

An ideal solenoid is expected to generate a dipole field that falls off quickly as you move away from the solenoid. The magnetic field at distance r along the axis of the solenoid is given by B = (Mo/ 2pie) (M/r^3) In this...

Physics lab formula question - help please]]>

A pole supporting a pedestrian and traffic light is shown. Neglecting the weight of the cables. Find the tension in the cables and and the support reactions at A,B,E.

Mass of traffic signal 20kg

Mass of pedestrian signal 10kg...

Equilibrium in 2d problem]]>

Ignoring air drag, how fast must you toss a ball straight up for it to take 2 seconds to return to same level you threw it from.

1. 20 m/s

2. 7.5 m/s

3. 15 m/s

4. 5 m/s

5. 10 m/s

vf = vi + a x t...

How fast is ball thrown up to come down in 2 seconds]]>

(bonus question: according to your favorite theory, what is the type of points in spacetime (that is, topology of spacetime)? is it like r^n for...

Type of wave functions]]>

Equation of a basic velocity-time graph]]>

Calculating Core Temperature of a Brown Dwarf]]>

I have run in to a number of problems while working through problems regarding Bessel and Modified Bessel Functions. At one point I run in to [itex]i^{m}e^{\frac{im\pi}{2}}[/itex] and it needs to equal [itex](-1)^m[/itex] but...

Problem while playing with Bessel functions]]>

##\frac{d^{2}y}{dr^2}+(\frac{1}{r}+1)y=0##

with the boundary conditions

##y(r) \rightarrow r \frac{dy}{dr}(0)## as ##r \rightarrow 0## and ##y(r) \rightarrow \sin(kr+\delta)## as ##r \rightarrow \infty##.

I know that the shooting method is the...

Boundary conditions shooting method]]>

So my question to you, on the small scale, what would be the most efficient dynamo system? Small scale meaning a handheld size device. I know energy can be generated using Faraday's law, when you move a magnet near a coil it...

Dynamo Mechanics]]>

More precisely, we know that in 5D, those scalars are real, so what is that makes them real here but complex there?]]>

Consider two solid dielectric spheres of radius ##a## separated by a dis-

tance ##R## (##R\gg a##).

One of the spheres has a charge ##q## and the other is

neutral. We scale up the linear dimensions of the

system by a factor of...

Force between charged and neutral sphere after scaling]]>

At out science Meet Up group we were talking about Interstellar travel. As usual, the properties of matter, energy brought up.

Regardless of how described in scientific jargon, FTL is all silly gobbledygook in science fiction books and...

Science Fantasy vs Science]]>

I REALLY need to recover them ASAP.

Which tools can I run in order to recover those files?

I've already tried the following:

1) Recover my files 5.x - both full partition recovery and PST file

2) Hetman...

Lost PST files after format - how to recover deleted files?]]>

Project Ideas for Graduate Classical Mechanics and Math Methods]]>

##\dot{Q}_{x}=-kA\Big(\frac{∂T} {∂x}\Big)##

Fourier's Law of Heat Conduction]]>

PGRE 830

GRE Quant: 167

GRE Verbal :156

Major GPA 3.7

Overall GPA 3.6

Honors Magna Cum Laude

Three semesters of research in Hamiltonian Chaos

No published papers

Took Three...

Chance of getting into a Physics Ph.D program]]>

Is there a non-degenerate 2x2 matrix that has only real eigenvalues but is not Hermitian? (Either find such a matrix, or prove that it doesn't exist)

Here's my...

Non-degenerate Hermitian Matrices and their Eigenvalues]]>

1. Let consider set “A” as follows:

A = {a1, a2, a3, a4… an} and also power set of A is set C:

C = {{}, {a1}, {a2}, {a3}, {a4}, {a1, a2}, {a1, a3},….{an}}

Are These Rules new Conjectures in Set Theory?]]>

Since the image is not clear ,the blocks on the left are 1 Kg(top) and 5kg(bottom) connected by a spring. On the...

Tension in the string]]>

I want the list to be appeared on other contents i mean over them.

Thanks in advance!]]>

A simple relativistic time question.]]>

How come for the following image when I assume block B slips up, block A does not move. The free body diagram at block B does not have a normal from the ground. This is a static friction problem....

Free body diagram logic]]>

I really like Mathematics and Physics, I do not really care for...

What Is Mathematic Physics? Not sure if I have a realistic]]>

View attachment 92398

$$V=\int_0^R\pi xdx\cdot y=\pi\int_o^R x\cdot Ax^2dx=\pi A\frac{R^4}{4}$$

Volume should be relative to R

Integral (area) of a revolved parabola]]>

I decided to make my own portable speakers (mono), which could be connected by means of an aux cable to my smartphone.

I don't know what's the output voltage of...

Design an audio power amplifier]]>

I know that to achieve LEO takes around 10km/s delta v.

But only 2km/s of that is to overcome the drag and gravity.

So you could shoot at 2km/s, get to LEO altitude then it falls back down because it is not at...

How fast to shoot a bullet for it to hit the moon?]]>

Use of the Biot Savart Law in Lifting Line theory]]>