Standard Definition and 1000 Threads

Homework Statement The question ask to find E[X]; E[X^2]; Var(X) for the standard normal distribution f(x)=1/\sqrt{2\pi}e^{-x^2/2}Homework Equations I found \begin{align} E[X]&=\int_{-\infty}^\infty \! x*1/\sqrt{2\pi}e^{-x^2/2} \, \mathrm{d} x\\ &=1/\sqrt{2\pi} ( \int_{-\infty}^0 \...

Hello, everyone. I understand the Standard Model and all of its quarks, leptons and bosons, but could someone show me the equation and simply explain it? I haven't been able to find it or an explanation of how it relates to the graphical representation of the Standard Model. Thanks in advance!

Homework Statement Given: Consider the following: city: Córdoba, Argentina Longitude = 64 deg 10 min W Latitude = 31 deg 28 min S Time zone = GMT -3 Date = 01 August On this date, the equation of time = -6 minutes. Assume no daylight saving time (a) Determine the standard time at solar noon...

In Frank Attix's book on Radialogical Physics Equation 1.2a reads σ = √(E) ≈ √(μ) σ= standard deviation of a single random measurement Where E is the expecation value of a stochastic process which approaches μ (μ is the average of measured values) as the number of measured values...

Hello, If have the standard deviation of acceleration (acceleration > 0) for a car. I also have the standard deviation of deceleration (acceleration <0). With these two figures is there a way to get the a standard deviation of the acceleration (both positive and negative)? Thanks

Okay, so we know that an equation of (x-a)^2 + (y-b)^2 = R^2 is the equation for a circle. Basically where x-a is change in the x-axis and y-b is the change in the y-axis. Here is the thing that I don't get, as quoted from my book. This equation in R^3 (three dimension) defines the cylinder...

Hello! I have a couple of questions on the following. Firstly, I was hoping someone could check my working and my reasoning. Secondly, I was wondering if someone knew an alternative way of solving this problem. I wanted to integrate this from x = -\infty to x = \infty: \lim_{a...

How to understand the "standard" momentum introduced in Weinberg's QFT I'm reading Weinberg's QFT Volume I. In page 63, you can find a formula (2.5.3) which states that the new state vector obtained by a Lorentz transformation is a linear combination of a whole bunch of other vectors...

Hello, I've been trying to find the answer to this question on the internet but no real luck so here goes: Imagine a signal My_signal which has two components, the actual signal A which is not constant over time and a noise component, we can call it N, where said noise component has a standard...

Homework Statement A recent summary for the distribution of cigarette taxes (in cents) among the 50 states and Washington, D.C. in the United States reported mean = 73 and standard deviation = 48. Based on these values, do you think that this distribution us bell-shaped? Justify your answer...

Can someone give me the names of all the particles that the standard model refers too remember the first 18... 6 quarks (up- down,top-botoom,nice-paradox) x 3 colors = 18 and i also remeber the mpozons (photon,gluion,higgs,w and z ) :confused: thank you ____________________ antonis...

Hey everyone, I'm not sure if there is an effective answer to my problem, but here goes: I am working on Ramachandran plots for short peptides (3 amino acids long). For every snapshot of the protein (this would be my data point) there are two angles being recorded, the phi and psi angles...

Hello all, I am trying to solve the FPE in 2D, The equation is (with implied summation over repeated indices): 0 = \left(- \displaystyle \frac{d}{dx_i} D_i^{(1)} + \frac{d}{dx_i}\frac{d}{dx_j} D_{ij}^{(2)}\right) ( n ) where my diffusion coefficients (the D are functions of position...

Hi; I'm working on a new model beynod the standard model one of MSSM with B-L symmetry I'm trying to install CompHep (Event Generator) on Linux OS (Fedora 17) but always i get the same error gcc -o bin/tab_view.exe src/plot/view_tab.o -lnum -lserv...

What do you make of this recent paper of Chamseddine and Connes? Resilience of the Spectral Standard Model The version of the Standard Model based on a product of the spacetime manifold with a finite noncommutative space had previously predicted a Higgs mass of 170 GeV. Supposedly this paper...

I live in Mexico and I am about to begin my PhD. Here in Mexico the standard books for a Msc or first terms of a PhD are almost the same in every univesity in Mexico. For example the Msc traditional program is something like this: First Year - Classical Mechanis-- with Goldstein's Book -...

Hello, Just had a question regarding statistical analysis. I'm trying to calculate the average of 4 numbers from a data set of 6 numbers in excel without manually choosing to average only the 4 numbers. e.g. 85 20 32 45 27 3 (total mean = 35.3 desired mean = 31) 100 30 27 40 21 1...

Of course we all know the standard symbols to use when drawing electrical circuits, but is there an analog for optical setups? I'm working of a poster and most of the symbols I'm using are just boxes with labels next to them, or just lines for mirrors and lenses.

Hello People, I'm and just somewhat confused about this topic. Lets say I have a sample set A with sample size= 101 mean =10 and sample stdv of 1 then sample set B with sample size= 100 Mean=15 with sample stdv of 2. If i add these two samples sets together I should get a new stdv that...

Sorry if this was posted in the wrong section. I'm only going to be a senior in high school and have never taken physics but I think I might want to study/major in it in college, obviously not for sure yet since it's still a long ways away. I've recently become interested in this stuff and have...

Hey guys! I'm debating learning a little non standard analysis but I have two problems; 1. I've seen a lot of critisism directed towards non standard analysis and I don't want to spend time learning about non standard analysis only to find out that it is logically flawed in some way 2. I've...

I can't even begin to type out the entire equation for the standard model of particle physics, it is just so immensely long and I don't have the time, energy, or patience to do so. So please excuse the fact that I don't have the equation on here to show exactly what I mean. Now, I understand...

i've read a lot of authors claim that the SM is enormously successful, that it has passed every experiment with flying colors, etc etc, i won't bother with quotes because i think everyone agrees on that. yet I've also read that the amount of dark energy that the SM predicts is off by anywhere...

Can someone explain me what is mass according to the Standard Model? I read that the Higgs boson "gives" mass to particles but I don´t understand what that means. :confused: Here's what I think I got so far : There is a field called Higgs field in all spacetime. It has a value for empty...

Homework Statement Chemical hand warmers produce heat when they're removed form their airtight plastic wrappers. These hand warmers utilize the oxidation of iron to form iron oxide. Calculate standard change of enthalpy for reaction and compute how much heat is produced from a warmer...

I have a standard syringe 1” diameter, with a freely moving plunger requiring uniform force to move the length of the cylinder providing smooth uniform travel. Cross sectional area = ∏r2 = 3.1415 * 0.5” * 0.5” = 0.785 in2 Negative pressure acting on the piston = 0.758 in2 * 14.7 psi =...

Homework Statement Given a polynomial P(x) and a divisor D(x), divide P(x) by D(x) and return the answer in the form P(x)/D(x) = Q(x) + R(x)/D(x) In this case: P(x) = 4x^2 - 3x - 7 D(x) = 2x -1 Homework Equations The one given above The Attempt at a Solution I solved the...

Homework Statement Just as the title suggests, although this is more to do with the formula. I know that for a sample, it implies it's a subset of a population. Why in the formula do you divide by n-1, whereas for calculating standard deviation for a population you divide by the total amount...

1) If X~N(μ,σ2, find the value of c in terms of σ such that P(μ-c ≤ X ≤ μ + c) = 0.95 Attempt: Ok so I have a feeling I will eventually need to reference a standard normal table, but I tried to standardize the rv first: P (-1 ≤ (X-μ)/c ≤ 1 ) = 0.95 Now here's where I'm stuck, what...

How do we graph a quadratic equation in the form ax^2+bx+c =0?, or an equation like , f(x)(or y)= [(x+b/2a)^2 - (D/4a^2)], where D = b^2 - 4ac? or how do we get a parabolic curve intersecting at its roots(of the quadratic equation) in the x axis?

In one of the standard candle methodologies, it is given in my book that by looking at the EM spectrum , we can know the temp. of the star by wien's law... To this point, everything's fine... now, the next sentence is FROM THE WIDTH OF THE SPECTRAL LINES, YOU CAN DETERMINE WHETHER OR NOT IT IS...

How is percentage uncertainty different from standard deviation ? I have five measurements and l calculated the average, standard deviation and variance. Do l need to calculate the percentage uncertainty ? Does percentage uncertainty give me any more information which the other values l...

Homework Statement Let Z follow a standard normal distribution. Compute E(Z^3) and E(Z^4) Homework Equations I know that mu is 0 and sigma is 1. And f(z) = e^(-z^2/2)/sqrt(2pi) The Attempt at a Solution I tried to take the integral of ∫Z^3 * f(z) from the integral from -∞ to ∞...

Homework Statement Find the cell potential of the equations Mg^+2 + 2e- --------> mg E=-2.36v Cl2 + e- ---------> 2cl- E=+1.36v Ans: -1.00v The Attempt at a Solution The answer says that it cl2 should be flipped. And cl2 is the anode But I don't understand why. I...

IUCSS Summer School on the Lorentz- and CPT-violating Standard Model Extension (SME) This program is going on now, at Indiana University. The title pretty much covers what the school is about. The SME simply takes the ordinary standard model and adds terms to the Lagrangian which violate...

I've done a decent amount of reading on the subject, and I used this method of course when reporting errors during lab experience I got as an undergraduate, but it was never quite fully explained to me why exactly we report a value +/- the standard deviation of the mean as our result. Why not...

Homework Statement Homework Equations ... The Attempt at a Solution Can someone just point me how to approach this? Do we take a random second degree polynomial and input 2x + 3 instead of x, then find the constants (eg. denoted by a , b , c) by putting the new equation equal to...

I was wondering if someone could please help me understand a simple problem of error propagation going from multiple measurements with errors to an average incorporating these errors. I have looked on several error propagation webpages (e.g. UC physics or UMaryland physics) but have yet to find...

There are 5 types of supersymmetric string or superstring: I, IIA, IIB, HO, and HE. Their low-energy limits have forms of supergravity, and some of them also have gauge fields. Here are their gauge symmetries: IIA, IIB: No gauge field I, HO: SO(32) HE: E8*E8 The gauge fields are all...

Must all models of ZFC (in a standard formulation) be at least countable? Why I think this: there are countably many instances of Replacement, and so, if a model is to satisfy Replacement, it must have at least countably many satisfactions of it. Does my question only apply to first-order...

Is it true that for every standard formulation T of ZFC, T ⊢ the power set of {naturals}? After all, the empty set axiom and the pairing axiom are in T, and so we get N. Then by the power set axiom we get P(N).

Standard from book: v(t)=K1e^(s1t)+K2e^(s2t) Can I have this below instead? v(t)=K1e^s1 + K1e^s2 - K2e^s3 - K2e^s4 I'm really confused, I sometimes get this when I do calculations. Any ideas? Thanks!

I hope this isn't deemed school related. It is something I learned in school, but I'm now trying to figure out a reaction model for my work. In the process of calculating the reaction constant, usually you first determine the Gibbs energy of formation of each species, find the difference...

Hello, I am trying to calculate what the margin of error for the standard deviation would be if each data point has a margin of error E. The standard deviation (for 3 data points) is defined as σ = \sqrt{\frac{(x_{1}-μ)^{2}+(x_{2}-μ)^{2}+(x_{3}-μ)^{2}}{3}} Where μ =...

Ashoke Sen has written a paper http://arxiv.org/abs/1205.0971 which uses path integrals in Euclidean gravity to compute "Logarithmic Corrections to Schwarzschild and Other Non-extremal Black Hole Entropy in Different Dimensions". Sen starts by listing several varieties of extremal black...

Homework Statement Find an equation in standard form for the conic , a)Ellipse: vertices (0,0) & (0,8), foci (0,2) & (0,6). b) hyperbola: vertices (-3,0) & (3,0), asymptotes y= ±2x Homework Equations Ellipse: (x-h)^2/b^2+(y-k)^2/a^2=1, vertices ± a from center, foci ± c from center...

Weinberg in his 1st book on QFT writes in the paragraph containing 2.5.12 that we may choose the states with standard momentum to be orthonormal. Isn't that just true because the states with any momentum are chosen to be orthonormal by the usual orthonormalization process of quantum mechanics...

I'm working with a \documentclass[12pt,a4paper]{article} document and plan on adjusting the margins using the geometry package, but for this it would be handy to know an estimate of the current margin widths. Does anybody know them, or where I can find it?

Hello buddies, Here is my question. It seems simple but at the same time does not seem to have an obvious answer to me. Given that you have two vectors \mathbf{u},\mathbf{v}. They are orthogonal \mathbf{u}^T\mathbf{v}=0 by standard dot product definition. They have norm one...

If I try to determine the standard electrode potential of Fe2+ -------> Fe3+ + e- What would be the concentrations of Fe ions ? Would I mix 1 mol/dm3 of Fe2+ and 1 mol/dm3 of Fe3+ ions ?