What is Symbol: Definition and 377 Discussions

A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise very different concepts and experiences. All communication (and data processing) is achieved through the use of symbols. Symbols take the form of words, sounds, gestures, ideas, or visual images and are used to convey other ideas and beliefs. For example, a red octagon is a common symbol for "STOP"; on maps, blue lines often represent rivers; and a red rose often symbolizes love and compassion. Numerals are symbols for numbers; letters of an alphabet may be symbols for certain phonemes; and personal names are symbols representing individuals. The variable 'x', in a mathematical equation, may symbolize the position of a particle in space.
The academic study of symbols is semiotics. In cartography, an organized collection of symbols forms a legend for a map.

View More On Wikipedia.org
Recent contents Top users
  1. B

    Symbol in Alan Turing's On Computable Numbers

    In Alan Turing's On Computable Numbers, he explains in his second paragraph the general notion of computable numbers. In doing so, he writes "In [symbol][symbol] 9, 10 I give some arguments...". I will include a screenshot of these symbols in this post. Do any of you know what these symbols...
  2. R

    Solve Mystery: Unknown Drawing Symbol 3.0

    Hello, Trying to set up some production checks and encountered a symbol I have never seen before. I googled machine stock symbols and found something along the lines of what I need to know but could not figure out what the 3.0 besides the squiggly line means. I have attached a PDF with the...
  3. Math Amateur

    MHB Simple Issue of oh symbol - exact sequences

    I am reading Adhikari and Adhikari's (A&A) book, "Basic Modern Algebra with Applications". I am currently focussed on Section 9.7 Exact Sequences. On page 387, A&A give Theorem 9.7.1. A&A use symbol in the exact sequences that looks like an oh but I think it should be a zero. They continue...
  4. P

    Convention for the symbol of Dielectric Constant

    I have come across the dielectric constant represented by two variants of epsilon. Is there any convention behind the two variants such that: \varepsilon is the SI Dielectric Constant \epsilon is the CGS Dielectric Constant or does it really depend on the writer and how frisky they feel?
  5. Math Amateur

    MHB X-like symbol for Cartesian Product (Blyth)

    In T. S. Blyth's book on Module Theory, the author uses a large 'times' symbol (similar to a capital X) for the Cartesian Product as seen in the text below (taken from Blyth page 58) Can someone help me with the Latex code for such a symbol?Peter
  6. ckirmser

    Symbol Meaning: Capital "V" with Crossbar

    I've run across a symbol on a NASA paper from 1984 that I am not familiar with and that I could not find in a web search. It's a capital 'V' with a horizontal cross bar through its center. Any ideas?
  7. G

    What symbol for ticks on ticker tape

    I used a ticker to measure to measure the acceleration of falling object. And and now I am writing report about it and the problem is what symbol is used for the marks on the ticker tape? Like for grams (g). What would you use for marks(?) ?
  8. G

    Measuring Acceleration of Falling Object: Mark Symbol?

    I used a ticker to measure to measure the acceleration of falling object. And and now I am writing report about it and the problem is what symbol is used for the marks on the ticker tape? Like for grams (g). What would you use for marks(?) ?
  9. Fredrik

    LaTeX Fixing LaTeX Symbol Display Issues on PhysicsForums

    In many posts with large LaTeX symbols, such as summation sigmas or the parentheses of a matrix, the upper part of those large symbols aren't displayed until you highlight them. If you then scroll them off the visible part of the page and then scroll back, they're messed up again. You should be...
  10. N

    Levi Civita symbol on Curl of Vector cross product

    Homework Statement Use the LC symbol to calculate the following: $$\nabla \times \frac{\vec{m} \times \hat{r}}{r^2}$$ Where ##\vec{m}## is just a vector, and ##\hat{r}## is the unit radial vector and ##r## is the length of the radial vector. Homework Equations On the Levi Civita symbol...
  11. R

    Einstein notation and the permutation symbol

    Homework Statement This is my first exposure to Einstein notation and I'm not sure if I'm understanding it entirely. Also I added this class after my instructor had already lectured about the topic and largely had to teach myself, so I ask for your patience in advance... The question is...
  12. N

    Levi-Civita symbol for cross products?

    Hi. Is using the Levi-Civita symbol to calculate cross-product combos like A x (B x C) allot faster than just using the good old determinant method? I ask because my lecturer in electrodynamics 2 told us it is better, but it seems to me that it's going to cost me time to learn to use this...
  13. E

    Levi civita symbol and kronecker delta identities in 4 dimensions

    I'm trying to explicitly show that \varepsilon^{0 i j k} \varepsilon_{0 i j l} = - 2 \delta^k_l I sort of went off the deep end and tried to express everything instead of using snazzy tricks and ended up with \begin{eqnarray*} \delta^{\mu \rho}_{\nu \sigma} & = & \delta^{\mu}_{\nu}...
  14. C

    Kronecker delta symbol in calculation question

    As part of a physics calculation, I have the following integral $$\int d \bar x a^{\sigma} \left[-\partial_{\mu}\left(\frac{\delta x^{\nu}}{\delta a^{\sigma}}\right) (\partial_{\nu}\Phi )\frac{\partial L}{\partial (\partial_{\mu}\Phi)} + \partial_{\mu}\left(\frac{\delta x^{\mu}}{\delta...
  15. TheDemx27

    OpenGL-SDL Unresolved External Symbol

    Hello. I am trying to get OpenGL working on my machine using SDL and glew. I've created a class 'Display' that pretty much just sets up the display and provides a place to draw things. I have 11 errors. In the errors it references both constructor and destructor in the Display class. Here is...
  16. S

    Cristoffel Symbol of spherical coordinates

    I just derived the 3-D Cristoffel symbol of the 2nd kind for spherical coordinates. I don't think I made any careless mistakes, but once again, I just want to verify that I am correct and I can't find any place on line that will give me the components of the symbol so I can check myself. Here...
  17. J

    What is the symbol for the continuous product in mathematics?

    If the discrete summation is symbolized by ##\sum## and the continuous by ##\int##, so, by analogoy, the discrete product is symbolized by ##\prod## and you already thought what is the symbol for the continuous product?
  18. darida

    Christoffel Symbol Ansatz for 4D Spacetime

    Ansatz metric of the four dimensional spacetime: ds^2=a^2 g_{ab}dx^a dx^b - du^2 where: a,b=0,1,2 a(u)=warped factor Christoffel symbol of a three dimensional AdS spacetime: \Gamma^{c}_{ab}= \frac{1}{2} g^{cd}(∂_b g_{da} + ∂_a g_{bd} - ∂_d g_{ba}) Now how to find \Gamma^{a}_{b}?
  19. C

    Ricci Tensor Proportional to Divergence of Christoffel Symbol?

    I'm reading an old article published by Kaluza "On the Unity Problem of Physics" where i encounter an expression for the Ricci tensor given by $$R_{\mu \nu} = \Gamma^\rho_{\ \mu \nu, \rho}$$ where he has used the weak field approximation ##g_{\mu \nu} = \eta_{\mu \nu} + h_{\mu \nu}## where...
  20. F

    Possible Errors in Writing Christoffel Symbols with a Symmetric Metric

    Homework Statement ¿Why \Gamma^{k}_{i j} = (1/2) g^{k p} (g_{i p ,j}+ g_{j p ,i}- g_{i j , p}) can't be writed like \Gamma^{k}_{i j} = (1/2) g^{k p} (2 g_{i p ,j}+g_{i j , p}) if i can say that the metric is symmetric? Homework Equations That is the relevant equation The Attempt at a...
  21. J

    Symbol help - Mirrors & units question

    Symbol help -- Mirrors & units question Calculate to the nearest 0.1000 degree the diffraction angle of the first order image produced by monochromatic light of wavelength 5890.0 A as the light passes through a grating of 5500.0 lines/cm. WHAT DOES THE SYMBOL 'A' MEAN?? My guess was 1^-10...
  22. maverick_starstrider

    What does an 2H- in front of a chemical symbol mean? (i.e. 2H-MoX_2)

    Title says it all. I'm reading a lot about the transition metal dichalcogenides and I often see something like 2H-MoS_2 What does that 2H- mean? My best guess is that it has something to do with a hexagonal lattice or stacking or something. Anybody know?
  23. Math Amateur

    MHB Help with 'connected sum" symbol #

    I just completed a post in the Topology and Advanced Geometry forum regarding the connected sum of two projective planes. I wanted to use the symbol # for the connected sum as is usual in the topology books I am studying - but just typing in the symbol 'upsets' latex and so my post cannot be...
  24. G

    What is the Meaning of \Subset Symbol?

    Hi. I was reading a chapter about Stationary Phase Method and I got stuck with this symbol \Subset. I looked it up on tables os mathematical symbols but could not find its meaning. Can you help me? Thank you.
  25. shanepitts

    Does anyone know what this symbol designates?

  26. H

    What does this special arrow symbol mean?

    I was reading the Wikipedia article at http://en.wikipedia.org/wiki/Euler-Lagrange_equation and came across several symbols I am not familiar with. An arrow pointing right with a short vertical bar on the left end. What does this special arrow mean? How is it different from an arrow without the...
  27. J

    Integral symbol for closed loops over functions?

    I find it sometimes confusing dealing with integrals of multi-valued functions in distinguishing a closed integration path, and an integration path which forms a closed loop over the function. They can of course be quite different. For example: $$\oint f(z)dz.$$ Now, is the integration to...
  28. O

    Shannon entropy - use to calculate the bit needed to encode a symbol

    To encode a symbol in binary form, I need 3 bits ,and I have 6 symbols. So I need 6*3=18 bits to encode "We are" into binary form. As shown in http://www.shannonentropy.netmark.pl/calculate My question: 3 bits to encode one then I have to use 16 bits, _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _. How to...
  29. K

    Understanding K-Map Symbols - Get Help Now!

    Hi, below image. My teacher use symbol in K-MAP. But not sure how it uses. Myattempt : i got 0 0 0 0 0 0 1 1 0 0 1 1 0 1 1 0 --> Using his technique. Can somebody help me out ?
  30. Petrus

    MHB Understanding the Meaning of "D_g" and "D_f" Symbols

    Hello MHB, I am reading about a rule which I got no clue what it's name is on english but I think that you Will understand. My question is what do they mean with that D_g and D_f Regards, |\pi\rangle
  31. W

    What is this Symbol - Is it Q? Answers Here

    I have checked it is not Greek, looks like Q , am I right? Thanks in advance
  32. G

    Adding angular momenta using levi-civta symbol

    Suppose you want to add 2 spin-1 particles. I understand you can get the j=1 triplet by $$e_{ijk}|j\rangle |k\rangle $$ where i, j, k run from -1, 0 , 1. The idea is that levi-civita symbol is a tensor under SO(3) rotations, so the contraction with the $$|j\rangle |k\rangle$$ tensor gives a...
  33. W

    What Is X Down & Up Arrows a (Limit from Left/Right)?

    X downward arrow a (is it limit from left) X upward arrow a (is it limit from right) ?
  34. B

    Poor Symbol choice - Principles of Mathematical Analysis by Rudin

    I've just started working through Rudin's Principles of Mathematical analysis. In my opinion, the choice of symbols doesn't promote "rigour" and encourages us to make needless assumptions. For example, when defining an ordered field, the fourth axiom for addition states: To every x...
  35. mishima

    Schematic Symbol Help? (SuperSID)

    Hi, can anyone help me identify the big blue boxes' schematic symbol? The actual physical component sort of looks like a small inductor or oscillator. SuperSID Schematic The purpose of this circuit is to be a preamplifier for VLF signals related to ionospheric disturbances, I believe.
  36. mnb96

    Problem with Einstein notation and Levi-Civita symbol

    Hello, I consider the permutations \sigma_i, where i\in \{1,\ldots,n\}, of the following kind: \sigma_i is obtained by choosing the i-th element from (1,..,n) and by shifting it to the first position; for instance \sigma_3 = (3,1,2,\ldots,n). The parity of \sigma_i is clearly (-1)^{i-1}. For...
  37. M

    Understanding the Wedge Symbol in an Equation

    Hi guys, Would you please help me by telling me the meaning of the wedge symbol in the equation attached? I=inertia. ω=angular velocity. Since the inertia is constant, then why do we need to add the second term? I mean why isn't the differentiation of (Iω) simply equal to (Iω')?
  38. R

    LaTeX What does this symbol mean and how do you type it in LaTeX?

    I'm reading Georgi Shilov's Linear Algebra and at the bottom of page 10 is has an equation a_{ij}=\lambda b_i+\mu c_i +\ldots +\tau ?_i Where the ? is there is a symbol that I don't know. It looks like a curly lowercase f (like an integral symbol with a short stroke through the top part). It...
  39. P

    Electronic symbol. Help identify a standard

    Sorry for my English. I write with the help of a translator from google. Please help determine what standards of a graphic symbol electric (number of the standard paragraph, the part number)? In one book in Russia were given 4 image transformer (for drawing in the U.S. and Europe). Аnd did...
  40. F

    The meaning of a symbol in Atomic Theory

    I happened across this little thing in a formula and I can't find what it stands for in any book/ website :confused: I think it stands for the ground state of an element, but I want to clarify first :smile: The symbol is E0 Its in this formula, which is derived from the energy of an...
  41. T

    Invariant symbol with four spinor indices

    Hi, from Srednickis QFT textbook, we know the following coupling of Lorentz group representations: (2,1)\otimes (2,1) = (1,1)_A \oplus (3,1)_S, which yields \epsilon_{a b} as an invariant symbol. Generalising, we can look at (2,1)\otimes (2,1) \otimes (2,1) \otimes (2,1) = (1,1) \oplus...
  42. Y

    9j symbol expansion in 6j symbols

    Hello everyone, I'm going through Edmond's Angular momentum in quantum mechanics and I found a particular expansion of the 9j symbol in terms of three 6j symbols which I didn't quite understand. The problem lies in equation 6.4.1 which I simply don't understand. On page 100/101...
  43. E

    (molecular spectroscopy)what is the meaning of the symbol

    Hi, everyone. In the picture attached, what is the meaning of 0oo? what should I read to understand the meaning?Thank you!
  44. S

    Question involving Levi-Civita symbol

    Can someone please explain to me why \epsilon_{ijk}\frac{\partial}{\partial x_i}\frac{\partial A_k}{\partial x_j} = 0 where A is a constant vector field.
  45. Y

    Why is the Symmetry Group of the 9j Symbol Isomorphic to S_3 x S_3 x S_2?

    Hello everyone, I read in Edmond's 'Angular momentum in Quantum Mechanics' that the symmetry group of the 9j symbol is isomorphic to the group S_3 \times S_3 \times S_2. Why is this? Can anyone shed some light on this?
  46. O

    What is the inverse triangle symbol represent?

    Homework Statement B=magnetic flux density . A is the vector potential of magnetic field. How to get the formula B=∇A Homework Equations http://en.wikipedia.org/wiki/Magnetic_moment The Attempt at a Solution B=magnetic flux density . A is the vector potential of magnetic field...
  47. M

    Symbol for partial derivative not used for partial integrals?

    {\frac{∂(xy)}{∂x}=x} Going backwards. If we took, ∫x dy we get xy+f(x) Now, the only way that ∫x dy is a valid operation, is if we know that we came from a partial derivative. Why, when taking a partial...
  48. A

    Proof of a vectoral differentation identity by levi civita symbol

    Homework Statement prove, ∇x(ψv)=ψ(∇xv)-vx(∇ψ) using levi civita symbol and tensor notations Homework Equations εijkεimn=δjnδkm-δknδjm The Attempt at a Solution i tried for nth component εnjk (d/dxj)εklm ψl vm εknjεklm (d/dxj) ψl vm using εijkεimn=δjnδkm-δknδjm...
  49. Y

    Isomorphism symmetry group of 6j symbol

    Hi everyone, I read in 'Angular momentum in Quantum Mechanics' by A.R Edmonds that the symmetry group of the 6j symbol is isomorphic to the symmetry group of a regular tetahedron. Is there an easy way of seeing this? I've tried working out what the symmetry relations of the 6j symbol do...
  50. spareine

    Why is V the symbol for voltage?

    I was wondering why V is a common symbol for voltage. The symbol is not named after the unit volt, because it is older than the volt unit, which dates from 1874. Before that, voltage was potential. In 1828 Green used the symbol V for the potential function which he introduced in his essay on...
Back
Top