Significance Definition and 279 Threads

Homework Statement A group of psychologists once measured 77 variables on a sample of schizophrenic people and a sample of people who were not schizophrenic. They compared the two samples using 77 separate significance tests. Two of these tests were significant at the 5% level. Suppose...

Dear fellow Physicists, I am writing to ask what the significance of the term (L/E) in neutrino oscillation is? From my initial understanding it determines the oscillation mode, so if you have an experiment of a baseline of 300km, you can adjust the neutrino beam energy to suit the particular...

I am aware that the commutation relation between conjugate variables shows that one quantity is the Fourier transform of the other, and so to imply the Heisenberg Uncertainty condition. So for example, the commutation relation between x, p (position and momentum respectively) leads to a non-zero...

Does the Bell inequality confirms the quantum mechanics? If answer is yes, why the violation of Bell inequality is more famous?

Hi people, Firstly I want to state that it will be my first message in this forum, I am new around here. I am studying electronical engineering, second year student. I am kind of interested in nanotechnology, hence I am trying to add the course whose name is "Material Science and Technology"...

This is not a homework problem, I'm going over some notes and seem to have a discrepancy. In a local region with no charge, del.E=0. Since the divergence is zero, there are no sources and sinks (ie charges). In my notes I have; "In cartesian co-ords, a solution of del.E=0 is a uniform...

Magnetic diffusivity is a term that appears in the induction equation, when we deal with plasma fluids. It has units of meter squared per second. I am unable to figure out what does the diffusion of plasma as a fluid implies.. It has something to do with magnetic field interacting with the...

I was wondering is there any way to quantify how much "power" a given selection has on the final outcome of a voting. More specifically, say you have a sample 330,000 people and you need to pick one. However, before you get to make a choice a pre-selection is applied and the sample is narrowed...

a wave equation is given as A = A cos (kx - ωt) so why if someone describes the wave equation to be A = A sin (ωt - kx) , the argument of the sin function changes by a minus sign? and is there a meaning to it? also i still don't really understand why the minus sign in the first equation...

For the following tests of significance 1 tests of mean difference for paired data - differences a calulated - forms a new random variable test its mean 2 two sample normal tests - looks at the differences in averages i have trouble picking which one to use for problems, i mean...

Hi there, In all text of QM I have, they tells that the density operator is hermitian. But without considering the math, from the physics base, why density operator must be hermitian? What's the physical significane of the eigenvalue of density matrix? Thanks

I'm in chapter two of H. S. Green's Matrix Mechanics and at a sticking point. In section 2.2 he gives the following scenario: An atom emits a photon with angular velocity ω, it has energy Ei before the emission and Ef after, so Ei - Ef = ħω. (That I can understand.) ψi and ψf are...

Homework Statement Hey guys. Anyone knows how can I avoid loss of significance in this function? http://img402.imageshack.us/img402/4216/33365715.jpg Thanks a lot.Homework Equations The Attempt at a Solution

Allow me to preface this by saying that I am only a student of physics, and that I have much respect for the work of those who came before me. I have familiarized myself with SR through my own research on the internet (perhaps a grave error), and I am quick to acknowledge that I do not...

hi, Do the addition of non-linear terms in action play any significant role in string theory?? if so, what is its significance in string cosmology? --- anuradha

In quantum mechanics, magnetic moment is equal to g factor times (gyromagnetic ratio x angular momentum). For orbital angular momentum, g=1, for electron spin angular momentum, g=2, for proton, it is 3.56. Is there any physical significance for this factor? why scientist introduce this factor...

What is the physical significance of the laplacian operator? The laplacian operator is the divergence of the gradient. I understand the intuitive meanings of both. The gradient when dotted against a unit vector gives the rate of change in that direction. The divergence is the flow in or out...

Homework Statement So, we are considering a spring-mass system, in which the mass at the end of the spring, M, is comparable to the mass of the spring, m. Using Newtons laws, I have to calculate, how significant the mass of the spring is. Homework Equations Mass at the end of the...

Hi everyone I have a question regarding a step in the proof of the Virial Theorem. Specifically suppose |E\rangle is a stationary state with energy E, i.e. \hat{H}|E\rangle = E|E\rangle Now, [\hat{r}\bullet\hat{p},\hat{H}] = i\hbar\left(\frac{p^2}{m} - \vec{r}\bullet\nabla...

1) can we say limit of a function f(x) such that limitx\rightarrowa f(x) gives the slope of this function around this point x = a. 2) can we say that to find slope i.e. limit of a function f(x) we always need a point "a" such that limitx\rightarrowa f(x) = slope 3) can we say that if left...

That is, if these cells even had anything to do with it. We're only going by the endosymbiotic theory.

What is the physcial signifcance of pi's appearance in a mathematical solution, if any?? Pi, the circumference of a circle divided by diameter, shows up in all sorts of mathematical solutions..classical, quantum, sometimes in unexpected mathematical results. As an example, Unruhs law is...

Homework Statement The data I'm working with is Sample mean(voltage)=128.25 variance=9/20 sample size=20 SD=3 Z=-2.61 The Attempt at a Solution The first part of what I was doing was a hypothesis test that the true voltage is 130 compared to the alternative less than 130...

Determine whether a correlation coefficient of r = –0.405 is significant at the 5% level for a sample size of 22.

Homework Statement In the general two-level atomic system of Fig. 14.2-3, τ2 Significance of the Saturation Photon-flux Density. In the general two-level atomic system of Fig. 14.2-3, τ2 represents the lifetime of level 2 in the absence of stimulated emission. In the presence of stimulated...

Can some help me to solve this question I have no idea where to start a) What is the physical significance of the intercept of the graph with the frequency axis (x-axis)? b) What is the physical significance of the intercept of the graph with the kinetic energy axis (y-axis)? c) Use the...

What is Physical Significance of "Lorentz Transforms"? Can anyone explain me what is physical significance of "Lorentz Transforms"? That means, apart from the math, how can we understand "how and why" length contraction or time dilation actually happen? and what is speed of light doing in...

I'm using a ATMEGA16 microcontroller. I was having problem getting it to work. I found somewhere on the internet that even if I'm not using the analog signals, I need to short the AVcc pin to the Vcc. Can anyone give any reason as to why we need to do this?

Hi Suppose we have a closed feedback system with loop gain = L(s) = G(s)H(s). The characteristic equation is 1 + L(s) = 0 What is the significance of the transformation s \rightarrow 1/s and what bearing does it have on root loci and Nyquist stability? I can see that the points s =...

[SOLVED] Significance of Average value of a AC signal Hello, I would like to know the significance of average value in a AC circuit. Let's consider a sinusoidal ac source with only a resistor in the circuit. The rms value of voltage and current indicate the equivalent DC value which would...

can anyone explain me the 1>significance 2>elements used to construct them 3>main usage to which industries of heat exchangers?

I recently had a test question posed to me that asked firstly for an explanation of the terms in the semi empircal mass forumla (which I gave correctly) but then went on to ask: For ^{40}_{20}Ca and ^{208}_{96}Pb estimate the fraction of the binding energy provided by the surface and...

So I have a system of equations (composed of force and moment eqns) and I can split them up into matrices which will then look like this: Ax = B I know the matrices A and B are correct, because when I plug in known values for x from a working prog, I get the correct values for B. So that must...

Homework Statement I have two distributions that I'm comparing. They are probably closest in resemblance to a logistic distribution. Anyway my problem is that I am wanting to determine if the difference in the negative side of the tail is statistically signifcant. The Attempt at a Solution...

Wht is the significance of an operator commuting with the hamiltonian?? Its definitely more than them being measurable simultaneously and precisely!

what is the tensor product's physical significance? I know what it does mathematically, but what does it mean. I have looked on textbooks and wikipedia but i still can't understand the physical signifcance.

I just have one question, what is it (yang-mills theory)? Could someone explain this to me please

what is a eigen value and eigen function? i have read a lot abt it...i understand the math behind it.. what is its physical significance of it?

Is there a significance of the number '47' in the 'Basic Structure' of the universe? Does this number represents in any way the basis of the structure of the universe?

what is the physical significance of the lie derivative? What is its purpose in tensor analysis?

Hello; I remember the days of muti variable calculus. The man said that divergence is equal to del dot the vector field. So on the exam he gave us a vector field, and I did del dot the given vector field and won big time. The other day I decided my concentration would be...

what is the meaning of orthogonal relationships in addition to right angles in the xyz coordinate system? for instance, if a 3 piece rocket separated in space in an orthogonal way...will there be any significance when compared to the 3 piece rocket that does not separate in an orthogonal...

We have to show that [Lx,Ly] = Lz [Ly,Lx] = -Lz [Lx,Lx] = 0 and I have done this. We then need to comment on the significance of these results, which I'm not sure of. I know in QM you get similar results for commutators of these quantities, and it means that you can't simultaneously know...

Homework Statement Let A be an arbitrary vector and e be a unit vector in some fixed direction.Show that A=e(A.e)+e x (A x e) What is the geometrical significance of each of the two terms? Homework Equations The Attempt at a Solution I can show it easily.As the first term (a dot...

Could somebody please tell me a workable definition of the term "chiral theory" , and also explain its significance? As far as I know, in a chiral theory not all the fermions obtain a mass but whether this is a definition or a derived result is not clear to me. Thanks in advance

what is the physical significance of othogonality condition? or what is meant when we say that two eigen states are orthogonal?

Hey guys, I have a problem with a polarization question... Consider the experiment H filter ← +45◦/ − 45◦ loop ← V photon. What is the output of the H filter? Write down an equation describing this outcome, in terms of the probability amplitudes for each step. Note that the +45◦/ − 45◦...

I'm working on a problem where I have a sample of 200 people. I have a total of 5 concepts which are viewed by each respondent, but are rotated so there is "no" bias due to viewing order. Obviously each concept does not have the opportunity to be in each of the 5 possible viewing positions...

what is R Parity and why?

Hello everybody, I'm a bit stuck on a statistical significance problem. I have the following data: The number of visitors for each of 2 web pages, and a number of conversions for each web page. (A conversion could be the number of visitors who completed the web form.) I would like to be able...