Threads Tagged with tensor Thread / Thread Starter Last Post Replies Views I was thinking... if the modulus of a vector can be calculated by ##\sqrt{\vec{v} \cdot \vec{v}}##, thus the modulus... Y 06:10 PM DrewD 1 117 General Math I've been working on Ex 5.4 in MTW. The maths is fairly straight forward, but I don't really understand what is going... Mar4-14 09:40 AM TerryW 2 248 Special & General Relativity 1. The problem statement, all variables and given/known data I have a question asking me to find the expectation... Mar4-14 06:36 AM Silversonic 4 158 Advanced Physics Homework I am trying to write the Einstein field equations $$R_{\mu\nu}-\frac{1}{2}g_{\mu\nu} R=\frac{8\pi G}{c^4}T_{\mu\nu}$$... Feb27-14 10:56 PM Nabigh R 2 316 Special & General Relativity I'm working through A. Zee's new EGR book, and I came to a step on tidal forces I couldn't follow. He presents the... Feb23-14 10:33 AM russelljbarry15 4 439 Special & General Relativity 1. The problem statement, all variables and given/known data ##D_{ijk}## is an array with ##3^3## elements, which is... Feb22-14 09:00 AM CAF123 1 138 Calculus & Beyond Homework I've been watching the Stanford lectures on GR by Leonard Susskind and according to him the metric tensor is not... Feb19-14 02:08 PM Chestermiller 9 432 Special & General Relativity We all know that the energy-momentum tensor for dust is just ##T^{\alpha\beta}=\rho_0 v^\alpha v^\beta##, where... Feb18-14 02:57 PM dEdt 0 229 Special & General Relativity If we use the "flux of 4-momentum" definition of the stress-energy tensor, it's not clear to me why it should be... Feb12-14 07:16 PM bcrowell 5 339 Special & General Relativity 1. The problem statement, all variables and given/known data I must determine the matrix elements of x^2 - y^2 in the... Feb11-14 06:05 PM Goddar 6 161 Advanced Physics Homework Hiya, I am a grad student who has had a couple semesters of GR. I am currently perusing a book about Two Spinors in... Feb10-14 02:34 PM dozappp 0 211 Special & General Relativity The divergence of a tensor field can be obtained by contracting the covariant derivative of said tensor field. I guess... Feb9-14 11:19 AM TrickyDicky 0 423 Differential Geometry Hello all, After a brief break from attempting to learn tensor calculus, I'm once again back at it. Today, I... Feb3-14 12:46 PM Nugatory 12 537 Special & General Relativity hey pf! in reading a book on viscous stresses i found the following:... Jan29-14 12:02 AM joshmccraney 9 208 Classical Physics In my note, we have written the field strength tensor as: F^{\mu\nu} =\partial ^\mu A^\nu -\partial ^\nu A^\mu... Jan28-14 07:10 PM ChrisVer 5 276 Quantum Physics Is there a coordinate independent/geometric definition of a tensor density? Jan28-14 10:45 AM bcrowell 3 241 Special & General Relativity Hi, I'm trying to write down the stress-energy tensor for a single photon in GR, but I'm running into trouble with... Jan27-14 11:44 AM bcrowell 5 300 Special & General Relativity Is there a simple intuitive description of what the Ricci tensor and scalar represent? I have what seems to me a... Jan26-14 06:13 AM pervect 2 241 Special & General Relativity How do you find the inverse of metric tensor when there are off-diagonals? More specifivally, given the (Kerr)... Jan25-14 10:48 AM Nabigh R 4 253 Special & General Relativity Tensors can be of type (n, m), denoting n covariant and m contravariant indicies. Rank is a concept that comes from... Jan24-14 09:50 PM jcsd 4 210 Special & General Relativity I noticed that sometimes exist a parallel between scalar and vector calculus, for example: ##v=at+v_0## ##s=\int... Jan24-14 09:43 AM Jhenrique 2 343 Linear & Abstract Algebra If I start with the stress-energy tensor T^{\mu\nu} of the electromagnetic field and then apply energy-momentum... Jan17-14 11:05 AM WannabeNewton 5 384 Special & General Relativity Suppose we have some two-dimensional Riemannian manifold ##M^2## with a metric tensor ##g##. Initially it is always... Jan17-14 09:01 AM center o bass 6 577 Differential Geometry According to Wikipedia, This definition doesn't sit well with me. Flux is defined as the rate that something... Jan16-14 10:31 PM pervect 10 368 Special & General Relativity 1. The problem statement, all variables and given/known data Problem as stated: Consider a vector A^a. Is the... Jan16-14 02:54 PM D H 1 156 Calculus & Beyond Homework 1. The problem statement, all variables and given/known data Hi, I am not sure if this is the right place for my... Jan12-14 04:53 AM theade88 15 548 Engineering, Comp Sci, & Technology Homework In the case of swarms of particles, the stress energy tensor can be derived by considering the flow of energy and... Jan10-14 08:38 PM samalkhaiat 5 440 Special & General Relativity Hi guys, Can anyone please help me to grasp a minor detail in the derivation of the Belinfante-Rosenfeld version of... Jan7-14 08:25 PM Michael_1812 5 469 Special & General Relativity 1. The problem statement, all variables and given/known data I have the following rank-2 tensor T = \nabla \cdot... Jan1-14 05:45 PM Niles 4 231 Calculus & Beyond Homework Good morning. I have calculated the components of the Ricci tensor for the Schwarzschild metric and they are all 0,... Jan1-14 11:10 AM CarlosLara 1 350 Special & General Relativity Hi, Consider a 2D laminar only rotating about the z axis, with the axis origin at the bottom left hand corner and... Dec30-13 11:06 AM SteamKing 4 226 Classical Physics I am computing the \hat{I} - moment of inertia tensor - of a cylinder with height 2h and radius R, about its axis of... Dec30-13 10:22 AM TSny 6 289 Introductory Physics Homework Hello, I have difficulty interpreting the following fact (I'm reading Cotinuum Mechanics by Spencer). The relative... Dec30-13 07:53 AM facenian 0 233 Classical Physics Given a particular system, how would one construct the stress-energy tensor? I was reading Mallett's paper and the... Dec30-13 02:55 AM WannabeNewton 15 761 Special & General Relativity I'm working on a problem that requires me to take the cartesian metric in 2D and convert (using the transformation... Dec29-13 09:12 PM PeterDonis 5 396 Special & General Relativity 1. The problem statement, all variables and given/known data Hi When I want to take the divergence of a rank-2... Dec29-13 04:36 PM 1MileCrash 1 252 Calculus & Beyond Homework Hey, I have been doing a few proofs and stumbled across this little problem. Trying to show the symmetry of the... Dec28-13 03:20 PM ProfDawgstein 7 491 Special & General Relativity I'm trying to clarify for myself the relation between the stress-energy tensor and the mass scalar term in metric... Dec28-13 01:06 AM WannabeNewton 3 395 Special & General Relativity Q) I am using index notation to show that ε^{0123}=-1 given that ε_{0123}=1. The soluton is: ... Dec26-13 07:34 PM Chestermiller 1 194 Introductory Physics Homework Q) I am using index notation to show that ε^{0123}=-1 given that ε_{0123}=1. The soluton is: ... Dec26-13 02:20 PM HallsofIvy 2 216 Calculus & Beyond Homework