Elementary Definition and 537 Threads

haruspex submitted a new PF Insights post Frequently Made Errors in Vectors - Elementary Use Continue reading the Original PF Insights Post.

Hi all, When we read this article http://www.slac.stanford.edu/pubs/beamline/27/1/27-1-weinberg.pdf it seem that there are not single answer to this question. Does the answer depends on what physical theory we use ? If we use string theory we don't get the same answer as if we use quantum...

Do elementary particles, e.g. electron, protons, etc, have material substance in the ordinary meaning of substance? If so, what is the substance?

When my eighth grade daughter was studying physics in her class, I watched a movie with her on the Hadron Collider (" Particle Fever "). We discussed atoms, electrons, protons, neutrons; we discussed orbits and statistics, and then down into the standard model and fermions, leptons, yadda...

When we say that elementary particles are wave-like in nature does that encompass, lead to and necessarily imply the fact that they travel in wave-like trajectories or is wave-like displacement a separate, distinct notion from their wave-like intrinsic natures? IH

Homework Statement Consider two masses of variable magnitude (M m) that are separated by a distance ( r ). Both masses are free to move. Calculate dr/dt. Homework Equations (See below) The Attempt at a Solution F = GMm / r2 a = Gm / r2 let k = Gm da/dr = -2kr-3 dr/da = (-2k)-1 r3 dr/da *...

I'm seeing a presentation of Euclidean geometry that isn't hand-holdy. I've looked at some textbooks used in high schools these days, and it's hard to find the axioms and theorems in the midst of all the condescension. I just want something that states the definitions, axioms and basic...

A presumably basic introductory equation manipulation in 2-d conformal field theory. How does from (when the metric is Euclidean) follow The right equation is clear (the metric is zero for different indices). But how do i get to the first equation on the left? thank you

From the elementary particles that science has been able to identify until now, are there any that appear to be useless, at least as far as we know? Or do all the identified particles play a role in the grand scheme of the universe?

Homework Statement Assuming that array1 and array2 are both arrays, why is it not possible to assign the contents of array2 to array1 with the following statement? array1 = array2;Homework EquationsThe Attempt at a Solution This is a question I just saw in a book. As far as I can tell the...

Hello, Am having this confusion that in Boltzmann approach to Statistical Mechanics, the phase space was divided into small phase cells whose magnitude was of the order of (h^f) but Boltzmann also made the assumption that the smallest phase cell must contain a large number of atoms. Doesn't this...

Homework Statement A supermarket always makes 40% gross margin on its cereals. So if it sells a box for $1, it has paid the supplier 60 c. When items are sold at a special offer price, the suppliers are expected to reduce their prices so that the supermarket still makes the same percentage...

http://www.nature.com/news/not-quite-so-elementary-my-dear-electron-1.10471 Scientists have split an electron into 3 quasiparticles in the lab, why isn't this updated on the standard model?

Hi everyone. I've been seeing certain posts circulate around social media, claiming that math is now taught differently in school than it was before. Here is one such image: I'm not sure if this is true, or if it's just one of those "back in MY day" rants. Anyways, I'd like to see discussion...

How Number of elementary particles in an atom are counted?

Hi, Can you help me in collecting equations of motion that are unsolvable with elementary methods (especially with high school maths)? One that I found is when I release a body attached to an ideal spring that can freely rotate around an axis. The reason why I need them is because I would like...

1. Get A from its inverse3. I believe it has something to do with the theorem that states: E1E2E3...EkA=I

Hi. Do there exits equipment that can read the elementary charge of atom? Or do we only know there charge by calculation? And the same question about there mass

Is it possible that they have the structure something like we used to picture them as? For example, what if we captured an electron and zoom in with a microscope that see infinitly small distances. Is it possible that if we zoomed into the electron close enough that we would see an object...

Just wondering if there's a precise definition of what it means to be an elementary particle. I had assumed it was related to not being able to convert it into multiple "smaller" things, but then a photon is called elementary when it can be converted into smaller energy positrons and electrons.

haruspex submitted a new PF Insights post Frequently Made Errors in Heat - Elementary Level Continue reading the Original PF Insights Post.

Hello all, I probably should have posted this in a math forum but I don't know of any. Can anyone recommend a book/books on elementary number theory with exercises? My math background is not very strong with very little knowledge of set theory so it should be understood by me. We're covering...

Hello.This is probably totally stupid question, but anyway... Is it possible to create bag made of particles with very strong positive charge and electrons using attracting force between them? If theoretically at least in some parallel universe yes, then if we keep shooting electrons inside...

Homework Statement I am currently working on a seemingly straightforward eigenvalue problem appearing as problem 1.8 in Sakurai's Modern QM. He asks us to find an eigenket \vert\vec S\cdot\hat n;+\rangle with \vec S\cdot\hat n\vert\vec S\cdot\hat n;+\rangle = \frac\hbar 2\vert\vec S\cdot\hat...

The rate law is given by R=k[A]^m[ B]^n where m,n needn't be equal to stoichiometric coefficients...but we use r=k[A]^a[ B]^b where a,b are stoichiometric coefficients when we use ratio rate of forward to rate of backward reaction in getting value of equilibrium constant K for any given reaction...

Homework Statement (a) e- + e+ -> e- + e+ (b) e- + e- -> e- + e- c) e- + e- -> e- + e- + u+ + u- d) y -> e+ + e- e) y + y -> y + y Homework EquationsThe Attempt at a Solution Part (a)[/B] Part (b) Part (c) Part (d) Part (e) Not sure what to do with this, since usually the...

I've been having fun with my new Lie Algebra text and it occurred to me that working out a couple of basic examples of my own would be a good idea. I got rather large surprise. The example I'm working with is SU(2) and I'm going through some basic properties it has. For all its uses in...

...and what form may they found normally? Somebody asked me just how many of the particles we know are possible (say, delta baryons) can be found in nature and what is their usual state - are there many particles to be found outside of atoms? Although there are enough "abundance of elements"...

Homework Statement Use the isoparametric formulation to express the following deflection information: U1=0.01cm, U2=0.025 cm with the corresponding global coordinates X1=5cm, X2=12cm Show the transformation equations between the global coordinate, the local coordinate, and the natural...

While browsing Wikipedia I bumped into this sentence that seemed partially wrong to me but maybe I didn't understand what it is referring to so would like for some expert to help me elucidate it: "Even if an elementary particle has a delocalized wavepacket, the wavepacket is in fact a quantum...

Homework Statement Show that the force on an elementary dipole of moment ##\mathbf{p}##, distance ##\mathbf{r}## from a point charge ##q## has components $$\begin{eqnarray} F_r &=& -\frac{qp\cos{\theta}}{2\pi\epsilon_0 r^3}\\ F_\theta &=& -\frac{qp\sin{\theta}}{4\pi\epsilon_0 r^3}...

Hi folks, can you guys share your experience and tips for understanding this subject? I find the sheer amount of problems and their novelty very difficult to reconcile. I mean I understand the definitions and theorems well and can usually apply them in straight forward cases, but the many...

Does Ross's book teach and/or use Epsilon-delta proof techniques?

I'm introducing myself to set theory. My reference doesn't seem to address the fact that 1/1 = 2/2 = 1. If we make a correspondence between natural numbers and rational numbers using sequential fractions, should we just skip equivalent fractions so as to make it a bijection? In other words, does...

I am looking for a book on physics to recommend to motivated laymen who don't want popularized information about the thing they are interested in but who want the real thing: what is physics, what methods are used, how to develop physical intuition, etc. Also, I am looking for a book with an...

Are there any tutorials that apply stochastic differential equations to the settings of elementary physics problems ? - for example, an object sliding down a not-frictionless ramp. The ramps of everyday life don't have a constant coefficient of friction. A better model for them would be...

Hello, I am having some confusion over elementary rate laws. This is a hydrodealkylation reaction. The specific reaction rates k1 and k4 are defined w.r.t. H2. If I want to write the rate law for the hydrogen radical for the termination step, would the elementary rate law be ##r_{H \bullet}...

Homework Statement http://postimg.org/image/hf6zpmykr/ Homework Equations intrinsic carrier density = ni = 10^10/cm^3 (for Si at 300K) The Attempt at a Solution Its a really elementary problem but I can't figure out the difference between some quantities. For example, free electrons and holes...

1.Problem: An electron with energy ##E## which is much higher than its restmass collides with a much much heavier particle "A" of mass ##m## which is at rest. Find the maximal transfer of four-momentum. (Elastic collision)2. Conservation of four momentum3. Everything in natural units. So I go...

I am currently working on old tests to prepare for my final in Elementary Calculus. I came across this problem and have no idea what to do. Any help would be greatly appreciated. A new Japanese restaurant is pricing a koi pond. A 4 foot deep, 8 foot radius circular pond looks nice, but...

Hello, I am working through some reaction engineering problems, and something in particular has caught my attention related more to chemistry I think than reaction engineering. Suppose we have a gas phase reaction ## A + 3B \rightarrow 2C ## If this is an elementary reaction, the rate law is...

Homework Statement Indicate the fundamental interactions through which the following processes occur.Justify. n -> p+ e- + -νe...1 p+p -> p+p+n+-n...2 π+ -> μ++ -νμ...3 γ -> e+ + e-...4 Homework EquationsThe Attempt at a Solution 1... is possible due to weak decay .electron antineutrino...

Hey physics forums! I was asked by my elementary school to help set up a system to make lights flash with the beat of music on a parade float. I'm a nuke engineer student at purdue but I think this is within my grasp. If It is too expensive or too much to make Christmas light flash with the beat...

Hi! (Cool) I am given the following exercise:Try to solve the diophantine equation $x^2+y^2=z^2$ , using methods of elementary Number Theory. So, do I have to write the proof of the theorem: The non-trivial solutions of $x^2+y^2=z^2$ are given by the formulas: $$x=\pm d(u^2-v^2), y=\pm 2duv...

I don't know if this is the right forum to post this, please move it if it's not. I am studying physics at university, and have to prepare a special research project in Lab 1 (Elementary mechanics) by my self and then present it to the rest of the group for a final grade in the course. The...

This is problem 20b from chapter I 4.10 of Apostol's Calculus I. The geometric mean $$G$$ of $$n$$ positive real numbers $$x_1,\ldots, x_n$$ is defined by the formula $$G=(x_1x_2\ldots x_n)^{1/n}$$. Let $$p$$ and $$q$$ be integers, $$q<0<p$$. From part (a) deduce that $$M_q<G<M_p$$ when...

A map h: = T.(M) ---> T.(M) is defined by h(X) = X + g(U,X)U where U ε T.(M) is a fixed vector with g(U,U) = -1. i: Give an expression for the components h^i (sub) j (This is "h" with a superscript i and subscript j) of h regarded as a tensor type (1,1) ii: Prove that h^2 = h. Interpret h...

why should Proca eqn be like ∂γ Fγμ + m2 Aμ = 0 but not ∂γ Fμγ + m2 Aμ = 0 ? another doubt is (λ-1 ω λ)μγ = λ-1 ρμ ωρσ λσγ ? why in λ-1 transformation got upper index in the second place but not in the first place? if someone clear my doubts...I would be thanful... regards.. Kau

I'm a little confused. During Beta(-) radiation, a neutron becomes a proton due to a down quark becoming an up quark. When this happens, a W(-) boson is emitted which almost immediately decays into an electron and an electron antineutrino. A W(+) boson, similarly, is emitted when a down quark...

Homework Statement I am struggling with what seems like a very simple problem from Terrence Tao's Introduction to Measure Theory book (which is available for free online by the way). What I am trying to prove is the following: Give an alternate proof of Lemma 1.1.2(ii) by showing that any two...