Mean Definition and 1000 Threads

I am studying Quantum Cryptography and I am quite new in Quantum area. I have read an article and I found this confusing statement: My questions: 1. The three stage protocol implementing multiphoton. What is the meaning of coherent states of mean photon number? 2. How to describe the quantum...

I am extremely confused by the use of the term coefficient of increase of something. For example , if it is stated that the index of refraction varies linearly with a coefficient of 2.5×10^-5, how is this coefficient defined? Is it simply the slope of the line plotted with index of refraction on...

I am studying Quantum Optics. A single photon state will give the mean photon number of 1, as shown the following equation: $$<\hat{n}>=<1|\hat{n}|1>=1.$$ For a two-photon number state, the similar calculation will be $$<\hat{n}>=<2|\hat{n}|2>=2.$$ And for a coherent state, it is...

Homework Statement How to determine variation of mean momentum of a nucleon with the mass number A of nucleus? Homework Equations R=R_0A^(1/3) The Attempt at a Solution Can't find a solution with elementary approach.

So there's a free particle with mass m. \begin{equation} \psi(x,0) = e^{ip_ox/\hbar}\cdot\begin{cases} x^2 & 0 \leq x < 1,\\ -x^2 + 4x -2 & 1 \leq x < 3,\\ x^2 -8x +16 & 3 \leq x \leq 4, \\ 0 & \text{otherwise}. \end{cases} \end{equation} What does each part of the piecewise represent...

I was reading an article about holographic principle and M-cosmology and how could they be used to interpret QM mechanics. But there's a part where it talks about holographic principle in a strange way to me. What does this article mean with this?: "Since for the participant observer the...

I'm Sorry for the vague title, but I don't know what to write. Can someone tell me the meaning of the passage I underlined? Thank you Ric

Homework Statement Find ##\langle x \rangle## in the momentum representation I am having trouble understanding some of the steps needed to get to the expression, assistance is greatly appreciated! Homework Equations 3. The Attempt at a Solution [/B] $$\langle x \rangle = \langle \psi | x |...

Hey! :o We have the following hypotheses: $$H_0: \mu\geq 60 \ \ \ , \ \ \ H_1:\mu<60$$ A test is executed with a sample of size $25$ and an estimated standard deviation $S'=8$. From the test we get a p-value of 5%. I want to determine the value of the mean of the sample $\overline{X}$. The...

Hi everyone, I do experiment in field of quantum optics and I want to calculate the mean of the number of photons (MNP). In the most of papers, MNP can be calculated by using average power which is measured by power meter. But my power meter is defective. For now, I have only the avalanche...

Does anyone know how can you prove that the mean value of the tensor operator S12 in all directions r is zero? S12 : http://prntscr.com/j3gn40 where s1, s2 are the spin operators of two nucleons.

Homework Statement Hello. There is a financial metric called time weighted rate of return, which is computed using the following formula: 1) if we compute daily returns, or other returns within a year: r tw = (1+r1) x (1+r2) x...x (1+r nth year), where r tw is the time weighted rate of return...

Homework Statement A closed hemispherical shell of radius R is filled with fluid at uniform pressure p. The net force of the fluid on the curved portion of the shell is given by:Homework Equations The Attempt at a Solution [/B] I'm not even posting the answers because I'm not looking to get...

What does this n(MAX)j=1 part mean? I'm not familiar with this notation. If you need more info, let me know. (p.s: Sorry if I'm posting this in the wrong place)

Hello people, I have 3 questions related to the mean speed of electrons in a period potential /lattice. I've read Ashcroft and Mermin's page 139 as well as the Apendix E. From what I understood, if one applies the momentum operator on the wavefunction of a Bloch electron, one doesn't get a...

Good day, From the first attachment... Why is "D" divided by "D1"? The book is saying that it is for normalizing "D" by the value of "D1". It's not quite clear ! The whole formula is to find the slope of this graph.

Hey. I was just wondering what people mean when they say physics and the universe is computable, I always thought it meant that the universe is measurable/calculable, but someone said to me that it meant the universe works like a computer/simulation. So, what does it actually mean?

A consequence of Coulomb's law is that oppositely charged particles have a negative potential energy. I'm having trouble undsrstanding how anything can have a negative potential energy and what consequences that has. Does it just mean the change in potential energy is negative or is it a matter...

Hey, What does the vertical line with the "I_b" on the bottom right mean? Link here: https://imgur.com/a/nII9g Thanks, -Yael

I've never been given a clean cut explanation of ground. I've heard some people refer to it as a common return path for current. Another as being a relative point that has a potential of 0V. Sometime people say Earth ground which I'm pretty sure actually means the ground of the Earth (not...

Homework Statement The same potato chip company reports that their bags of family sized chips each follows an approx. Normal distribution with a mean of 10.72 ounces and a standard deviation of 0.2 ounces. If the company wants to ship these chips into boxes that contain 6 bags, what would be...

Homework Statement Homework Equations The Attempt at a Solution I'm confused avout questions 2-3. The answers for 2-2 is 1 So the answer for 2-3 is $$\frac{1}{3}$$ But, how the area looks like? Because $$ x^2 $$ will be an open curve upside? There's no boundary for above side.

Hi, I was wondering what is the physical meaning of these integrals: \begin{equation} \int_{-\infty}^{\infty} \psi \psi^* dx = 0 \end{equation}\begin{equation} \int_{-\infty}^{\infty} \psi x \psi^* dx = 0 \end{equation} \begin{equation} \int_{-\infty}^{\infty} \psi p \psi^* dx = NA...

Hi, So my power system book has a diagram for zero sequence impedance. I cannot find the full form of ZPB. I googled it up but couldn't come across anything.

So the quantum suicide experiment says that if there is a 50-50 chance of you dying, let's say by a gun shot to the face (like Schrodinger's cat). You die in one universe, but survive in the other. Let's say the gun shoots and you die, does your conciousness shift to the one where you are alive...

Traditionally, derivatives are taught as a function that have... "Whole" transitions. Take the following example: If you have the function f(x) = x^2, we find that f'(x) = 2x, and that f''(x) = 2. In other words, it has a first and a second derivative. But what would it even mean to take a...

I was wondering and this might be a stupid question... I have approx. 200+ armatures with a GAS number stamped on them Like "GAS 3237". There are probably 20 different numbers or so. Where can I find a list of what these numbers are or mean?

I was reading a book on black holes by Kip Thorne the other day, well weeks really, and I came across this in one of the footnotes 10^10^79 (10 to the power of 10 to the power of 79) And I really don't know what it means. Does it just mean what it says? If it does can you raise a power to a power?

Homework Statement n/a Homework Equations n/a The Attempt at a Solution n/a Just a question. I keep seeing that in SN2 reactions, sometimes a molecule is quenched by H2O or H3O. I've seen it turn an O- into an OH and also a heteroatom into an H. What exactly is going on here?

What exactly does it mean to simplify an expression. I understand that an expression becomes more simple when you combine like terms but what other conditions are there? Is x(5x+1) more or less simple than 5x^2 +x? Do square roots need to be moved to the numerator?

An exercise asks me to determine whether the following operator is Hermitian: {\left( {\frac{d}{{dx}}} \right)^ * }. I don't even know what that expression means. a) Differentiate with respect to x, then take the complex conjugate of the result? b) Take the complex conjugate, then...

Data for the mean Earth temperatur: - For example, the average annual temperature for the globe between 1951 and 1980 was around 57.2 degrees Fahrenheit (14 degrees Celsius). (UCAR). - The global mean surface temperature is 14.46 °C computed from MODIS data (2001-2012). - Estimated Jan 1951-Dec...

1. The problem statement, all variables, and given/known data 1. S = 12t, where S = displacement ant t = time (in seconds) 2. S = 490t^2, where S = displacement and t = time (in seconds) What do the two equations mean here? I don't understand what they want to mean here. I am confused. Could...

C12H22O11 = 342 g/mol What does it mean?

Hi guys, I have a question about what is a double degree. I know the question sounds stupid, but in Italy, or maybe in Europe we have a different conception. For example when we say double degree that means that you graduate from two different university for the same major. Let's make an...

1. The problem statement Consider a particle of mass m under the action of the one-dimensional harmonic oscillator potential. The Hamiltonian is given by H = \frac{p^2}{2m} + \frac{m \omega ^2 x^2}{2} Knowing that the ground state of the particle at a certain instant is described by the wave...

Hello, I'm currently doing vectors in class, but I don't know what these parts mean. Especially φ(a,b). I understand cos(φ), but I don't understand cos(φ(a,b)). φ is the angle between two vectors a and b, but what does the (a,b) part add? I tried to google, but I couldn't really find...

For the Image given, i have to calculate reluctances of air gap and core which depends on respective mean path lengths. For the left hand core, the mean path length calculated in the solution manual is 1.11 meter . However what I don't understand is that why is the length of the air gap included...

If we were to quantize the Dirac field using commutation relations instead of anticommutation relations we would end up with the Hamiltonian, see Peskin and Schroeder $$ H = \int\frac{d^3p}{(2\pi)^3}E_p \sum_{s=1}^2 \Big( a^{s\dagger}_\textbf{p}a^s_\textbf{p}...

I am new to Calculus and not exactly sure what this means. Any help explaining it would be greatly appreciated. :)

Homework Statement I as just hoping someone could help me parse the notation here. What does the superscript "d" mean in the differential of the integral? Thanks!

Hello all! I recently had a few major changes in my thinking about what I want to do with my life. For awhile, I thought I wanted to pursue my PhD in physics, so I signed up for the GRE and with it I signed up for the GRE Search tool, which I guess is a tool schools can use to find potential...

It is an X like in a cross product but with a vertical line connecting upper-left and lower-left endpoints. I will write it as |X . Example context: R^4 |X SL(2,C) where the R and C are real numbers and complex numbers.

Homework Statement Homework EquationsThe Attempt at a Solution ## V(r) = \frac 1{r^3} \left( A - Br^2 \right )## At the bottom of the well, r is verry small. So, ## V(r) = \frac A{r^3}## Assuming the validation of Equipartition of energy theorem, since the degrees of freedom is 1, the...

I was reading the *Statistical Physics An Introductory Course* by Daniel J.Amit and need some help to understand a certain passage: In an isolated composite system of two paramagnetic system: System a with ##N_a## spins and a magnetic field ##H_a ## System b with ##N_b## spins and a...

How can I understand logically this equations? it seems to me like an avarage of equation...but why each term is specifically in the way it is? Thank you

So say a wave is described by Acos(Φ), completely real. Then the to use Euler's Eq, we we say the wave is AeiΦ, which is expanded to Acos(Φ) + iAsin(Φ). We tell ourselves that we just ignore the imaginary part and only keep the real part. And if intensity is |AeiΦ|2, which is (Acos(Φ) +...

What does object space and image space mean in optics?

Homework Statement System of two energy levels, E_0 and E_1 is populated by N particles, at temperature T. The particles populate the levels according to the classical (Maxwell-Boltzmann) distribution law. (i) Write an expression for the average energy per particle. Homework EquationsThe...

Homework Statement A state of a particle in the potential box of width a with infinitely high walls is described by the wave function: Ψ(x)=Ax(x-a) Find the probability distribution of various value of particle energy, mean value and mean square fluctuation of energy. Homework Equations...