Writing Definition and 688 Threads

Anyone know where I can, possiblely, find the EFE's written only in terms of the metric tensor and the stress-energy tensor? I know that the Ricci Curvature tensor and the Ricci scalar are derived (eventually) from the metric tensor (after a roundabout way through Christoffel symbols). The...

This is my first academic paper that I am writing completely by myself and need some advice from you published authors out there. The journal I am writing for says that they do not want you to cite any review articles. A review article that I am getting information from has some info I want to...

Hi all, so... now that I have to write lab reports at uni level, I'm starting to wonder what software would be best suited for the task. Currently, my workflow goes like this: iWork Pages (or MS Word) for the actual report. imported LaTeX (or Mathematica) PDFs for mathematical equations...

Homework Statement f(t)= 4t t<1 f(t)= 4 t≥1 I need to write f(t) in terms of H(t) Homework Equations H(t-t0)=0 for t<t0 = 1 for t≥t0 The Attempt at a Solution I am not too sure how it is done, as what I read online, people can just immediately...

Homework Statement Assume a rigid body with a massless rod that pivots about point O. Displacement x is measured from equilibrium position. Assuming x is small, that the weight at the end of the rod is 5N and spring constant is 400n/m, obtain the dynamical equation of the system...

I'm writing a scifi story about a human undergoing rapid evolution due to his being repeatedly "connected" to an alien biological machine,that would be controlling the evolution through some kind of program. one of the changes would be a "master" cell that was able to regulate clusters of...

Hi everyone Long time since i posted something. (May be i have posted at the wrong place, Doc Al...feel free to move it) I am in my first year... Basically i will have to start writing research papers from the next year... But i am really interested to start from the first year... I...

I'm currently trying to write a report at the moment with some tables for some data, and it would be ideal for me to put these tables side-by-side if possible. However, I'm not sure as to how this can be achieved; I've currently doing \documentclass{article} with multiple figures of graphs...

I'm trying to write a piece of code for the rule 'i before e except after c'. Heres what I have so far. if(str[4]=='c') && if(str[5]=='ei') printf ("yes\n"); else printf("no\n"); I don't really want the answer but I just want to know if I'm going in the right direction.

Homework Statement We started K-Maps not too long ago, I have no idea how to read these or write these. I am only able to set them up, but as far as understanding prime implicants, max terms, min terms I feel I know nothing. Correct me if I am wrong, but 0's are max terms and 1's are min...

I just have a general question that I came up with while doing homework for my database class. I was asked to write a specific query, and when I checked my answer against the posted solutions, it was different. I don't know that much SQL (yet), but I'm pretty sure that my query would produce the...

for a project i have to open, edit and save a varying amount of files. I use a MATLAB code for this. It works fine and imports all the .sp files in the directory with the fopen() command. The only problem i still have is that i also want to change the extension of the files. Right now i use...

I am doing the write up for one of my labs. In this write up we combined HCl with some of the elements from from the Carbon group (C, Si, Sn, Pb). Naturally, my professor wants us to express what occurred in equation form. But I am not sure if I am doing it correctly... here is what I have...

My friend was moved the way his psychology teacher gives lectures. He is considering writing a few paged essay, detailing why the lectures are so good, and effective. He asked me if it's ok to send the letter to the principal of the universitly. I really don't know. Could it hurt the professor...

Homework Statement This isn't a homework problem, but I just had a general question about the language of writing proofs. I often see words like "suppose", "let", and "consider" in proofs. Could someone explain to me if there are rules to applying these? It doesn't seem like they are just...

I end up writing a LOT when trying to prove stuff. I can go through a legal pad in a week for one class -- and the writing is just scratchwork, so it's all trash. That is too wasteful for me, so I got a paper-sized whiteboard, but I am finding that I need a bigger one. How big should I go...

Hi, I need some help in writing the Hamiltonian function for the following dynamical systems. 1) u''+u=A (1+2*u+3*u^2) 2) u''+u=A/((1-u)^2); In both cases A is a constant and u is a function of t. Any help would be greatly appreciated. Thank you. Manish

Homework Statement What is the proper notation for writing the set of all ordered pairs of real numbers that are in quadrant 1 and 3 of the real plane? Homework Equations The Attempt at a Solution I was thinking something like $\left\{...

Hey guys, I have been searching for an answer to this question for quite some time and I have found nothing. This should be pretty simple, yet for some frustrating reason, I can not get it to work. I want to start some writing 4.5 inches from the top of the page. I am doing...

I use linux on a pc and one of my friends who uses a mac wants me to write a small app for him. It doesn't need any GUI of anything, just a few lines in C++ with a bitmap image for input and an output to a text file. Is there a way for me to compile it in linux so that he'll be able to use it...

I have no idea how to write these two reactions as net ionic equations in order to show relevancy to their respective pH: Na2CO3 + HCl (pH of 10.36) I know that it dissociates into OH- ions since it has a very basic pH and NaHSO4 + HCl (pH of 4.18) I also know that this...

Hello PF members, I need a small help in latex in writing a report! How to include footnotes (in the form of symbol!). For e.g., i have 5 authors..for all these 5 authors i can use $^1$, $^2$, etc as author's address. I mean all are just numbers.. Now for 2 of the 5 authors i want add...

Hey to be honest I am new and don't know very much about science. I don't know if this is even the right place to post this. I am writing a science fiction novel, and basically I want to know, if it is possible for a special element (go with me here) to destroy all types of metal without...

(edit: sorry I made a mistake in the thread title. It's the output that isn't a factor of every component in the equation, that is giving me trouble) Hi! I'm new here, and any help would be greatly appreciated. Homework Statement I am modelling a mass-spring-damper system in which the...

[FONT="Book Antiqua"][SIZE="4"]Hello, I am in the writting stage of my master thesis. Actually, I wrote it while I am in progress, but I need to fulfill the requirements of the Faculty of Gradguate Studies (FGS) for the thesis. In doing so, I will face some problems using LATEX for sure...

can somebody help me on writting a program that displays yo to yn+1 when n=100 and store them in a file. y"=cos(t)*y+y y(0)=1 y'(0)=0 h=0.1 y'=z z'=z'*cos(t)+y yn+1=zn+h*zn*(cos(tn))+yn) tn=t+nh

A little funky title but I couldn't help but word it that way. Anyway I was thinking still have time to make up my mind between going for a physics Ph.D or Engineering B.S. So i figured i could go still for for guidance and hopefully ask some questions that others havn't asked that may intrigue...

In papers, when should I spell a number (sixteen) and when I should write it using numerals (16)?

I am trying to write the term "Sin^2 theta * Sin 2 phi" in terms of spherical Harmonics (they form a combination of Y(2,-2) and Y(2,2)) but the term I get contains the imaginary number 'i'. Am I doing something wrong.. In fact this term is a part of a Hamiltonian and when I get the eigenvalues I...

Homework Statement I have the trajectories of a particle in the space-time: \tau(\sigma) = \frac{1}{a}senh(\sigma) x(\sigma) = \frac{1}{a}cosh(\sigma) How can I write this equations depending on proper time t of the particle? Homework Equations The Attempt at a...

I'm having one hell of a time writing my thesis! I'm writing it as I go because I like to think in terms of systems engineering (breaking things down into blocks). I'm certainly no where near done with my research; however, there are lots of stuff I have done that can be written up now. Our...

Homework Statement How to write an engineering report? Could you refer me to links for how to write engineering reports? I had been given a task to make a jib crane, and then to write an engineering report. Anything would be helpful. Cheers Homework Equations The...

I'm looking for major help on writing an interactive program to run hangman. It can be user inputted or using an array. I just don't know what to do.

Hello! I know how to do a matrice in latex like this: \[ \begin{bmatrix} a & b & c \\ d & e & f \\ g & h & i \end{bmatrix} \] How do I write severell matrices on one row like : "matrix_A times another matrix_B = answer " And how can I label the matrices so I can refer to...

I'm just playing with ideas for the future right now, but I saw a flyer for MIT's http://web.mit.edu/sciwrite/index.html" (1 year). If I was able to fund it and wanted to do the program, but also wanted to do grad school, should I wait to do the science writing grad program before a Ph.D or does...

I heard this on NPR's Morning Edition this morning. http://www.npr.org/templates/story/story.php?storyId=103140512 If one wants to be a better writer, this is the book to read.

Does ne1 know of any free math programs that write formulas and make graphs? I need one for a project I'm working on.

Homework Statement If linearly dependent, write one matrix as a linear combination of the rest. \left[\begin{array}{cc} 1&1 \\ 2&1 \end{array}\right] \left[\begin{array}{cc} 1&0 \\ 0&2 \end{array}\right] \left[\begin{array}{cc} 0&3 \\ 2&1 \end{array}\right] \left[\begin{array}{cc} 4&6 \\ 8&6...

I'm in the final year of my undergraduate studies and now I'm writing my final year report. In my thesis, there're certain things I need to mention and I find that I lack of words to describe the phenomena. However, I find there's a certain paragraph in a book that describe very well. I...

Homework Statement For each of the following situations, identify those for which a reaction likely to occur. For those that do occur, white a net ionic equation. a) Chromium dipped into silver nitrate. b) Gold immersed in hydrochloric acid c) Nickel pellets dropped into calcium acetate...

Homework Statement Write word equations to show the changes in: 1)Hydrochloric Acid and Mossy Zinc 2)Manganese Dioxide and Hydrogen Peroxide 3)Hydrochloric Acid and Rolaids 4)Passing electricity through copper (II) chloride (electrolysis) 5)Silver nitrate and sodium chloride...

Do you think writing in cursive is going out of style? I heard someone say today that they might stop teaching it because everyone seemed to be writing in the standard, non-cursive way or just using a computer and not really writing by hand at all very much. There are some disadvantages to...

Homework Statement Consider the map F: C0([a,b],Rn) --> R, F(\phi)=\int\phi(t)\phi(t)dt (This is the integral from a to b). Write F as a composition of three maps, each of which is linear or bilinear. Then use the chain rule and generalized product rule to compute DF(\phi). Homework...

if i am asked to find a basis for a vector subspace, am i meant to jus write one possible option, for example basis: (8,0,0)(0,6,0)(0,0,2) or am i supposed to write the whole span basis: sp{(8,0,0)(0,6,0)(0,0,2)} or am i meant to write it with parameters basis: a(8,0,0) +...

Homework Statement A projectile is launched with a speed of 50.0 m/s and an angle of 40.0o above the horizontal, from the top of a 75.0 m high cliff onto a flat valley floor at the base of the cliff. Assume that g = 10.0 m/s2 and ignore aerodynamic effects. Write equations for position...

Homework Statement An object emitting light with a wavelength of L is traveling away from you with a relative speed of v, which is small compared to the speed of light. Write down the algebraic expression for the fractional change in wavelength between what you observe and what the object...

Hi I need to Interview a Computer or Electrical Engineer for an assignment. If somebody could answer the following questions it would be much appreciated. What type of communications do you write ( Proposals, instructions, memos, etc)? What types of readers do you address? What is your...

Hello, everyone: I have a bit of a strange question, but I am a writer and I'm writing a story about a college math student. What I'm in need of is an example of a question in Differential Geometry involving a "Submersion" (preferably a word problem), the process, and the solution. The...

For some reason it seems like I am just incapable of doing proofs. I have trouble with even very simple proofs. Admittedly I probably haven't tried as heard as I could because writing proofs just annoys me. Last semester I was talking a course called Discrete Math at my college which...

So who else is writing a thesis over the christmas holidays? Can anyone help me with this latex problem: I'm using \begin{align} and \end{align} for this equation, but it looks ugly... http://www.freeimagehosting.net/uploads/cf1b1c46ab.gif How can I fix that first line?