Holographic Definition and 123 Threads

Holography is a technique which enables a wavefront to be recorded and later re-constructed. Holography is best known as a method of generating three-dimensional images but it also has a wide range of other applications. In principle, it is possible to make a hologram for any type of wave.
A hologram is made by superimposing a second wavefront (normally called the reference beam) on the wavefront of interest, thereby generating an interference pattern which is recorded on a physical medium. When only the second wavefront illuminates the interference pattern, it is diffracted to recreate the original wavefront. Holograms can also be computer-generated by modelling the two wavefronts and adding them together digitally. The resulting digital image is then printed onto a suitable mask or film and illuminated by a suitable source to reconstruct the wavefront of interest.

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  1. P

    Very small holographic laser projectors and diffraction.

    In thinking about what it would take to make a feasible invisibility cloak or holographic disguise or perfect hologram room, I've imagined something that works like this: A light beam "image" is projected onto a device designed to refract or reflect it in all directions, but only 1 color in any...
  2. I

    Holographic Principle Projection

    Hi. I have a question about the Holographic Principle. I've been looking up things about it for a while now, and I think I understand it. The total content of a space is propositional to the area surrounding it and not the volume. The thing I'm having trouble with is how everything seems 3d...
  3. S

    Holographic principle in reverse

    I'm getting a rough idea of the holographic principle relating the shannon entropy of a boundary surface to the thermodynamic entropy contained within the bounded volume. So far as I understand the primary claim is that the total information needed to describe the entirety of the internal...
  4. M

    Susskind process and holographic principle

    Why is it that Susskind in describing the holographic principle - why is it that he considers a quantized universe?
  5. I

    Could the Holographic Universe Theory Explain Time Dilation?

    Hi all, I was thinking about the Holographic Universe theory today and wondered... ...If the universe was a hologram, could it explain why time slows down the faster you travel due to holograms being made of light? Is it impossible to travel faster than the speed of light because you would...
  6. T

    Holographic principle, mathematical universe & dimensional reduction

    If the holographic principle says that the the observable universe could be represented as a two dimensional surface, and we accept the idea that the universe is itself a mathematical object, and cantor showed that we could in some cases represent higher dimensional sets within lower dimensional...
  7. M

    What's the latest development in Holographic display?

    I don't know where to post this so here it is. I've googled it, found something interesting by USC Graphic lab, turns out it's a rotating mirror, emulating a holographic displayer, but fair enough, it's still quite amazing. http://www.wired.com/gadgetlab/2008/06/usc-lab-creates/ Is...
  8. L

    Can the Holographic Principle Explain All Physical Information in a Surface?

    What is the reason/ explanation (possibly in a nutshell!) that all the physical information of a volume can be encoded in the surface surrounding that volume?Because, you know, that sounds silly, at first! I browsed some introductory sources, but could not find any quick answers. Also, if...
  9. E

    The Holographic Universe: Dividing Reality into Bits

    Hey guys, can anyone explained to me this theory. To my knowledge it talks states that everything can be divided and broken down into the smallest bit of information. A hologram can be divided (a limited number of times?) and still retain it's image. I'm trying to do a paper on it because it's...
  10. M

    Exploring Holographic Hierarchy in the Gaussian Matrix Model

    This paper seems to be another entry in the LQG/string crossover competition: http://arxiv.org/abs/1303.3246 Holographic Hierarchy in the Gaussian Matrix Model via the Fuzzy Sphere Authors: David Garner, Sanjaye Ramgoolam (Submitted on 13 Mar 2013) The Gaussian Hermitian matrix model was...
  11. nomadreid

    In holographic principle, the boundary is wrt which light cone?

    It is stated that in the holographic principle (e.g., in http://en.wikipedia.org/wiki/Holographic_principle) that the the description of a volume of space is encoded on a light-like boundary to the region. But with respect to which position in the volume? In a black hole, it is clear, because...
  12. T

    Holographic grating - can we calculate efficiency for each order?

    Hi, I'm new to working with gratings. From using the basic grating eqn., I'm able to model the diffraction angles for each order with different angles of incidence upon the grating and I can calculate the dispersion given a broadband source with known minimum and maximum wavelength...
  13. L

    Does the holographic principle remove the need for dark matter

    I appreciate that the holographic principle is just a theory, but if I accept it and the related aspects of string theory, does it do away with the need for dark matter (since I think that the mass approaches infinity as one changes the reference frame in which one observes the the mass)...
  14. D

    Holographic Principle: Quantum Gravity & String Theory

    Hi All, :smile: 1. Is it a property of all quantum gravity theories? 2. Do all string theorists and not just Susskind, Maldacena, t'Hooft, believe HP to be property of string theory? 3. As most prominent basis for Holographic Principle is associated with dependence of Black Hole Entropy...
  15. S

    Holographic principle and conservation of energy

    Hi PF! I was wondering, if the holographic principle (from string theory) really can be true. I see some physical flaws in the way it works. Here is why: Suppose that the second law of thermodynamics is true. It states that for any system, the multiplicity of the system must increase, ergo...
  16. J

    Holographic Universe Interpretation

    I was watching "The Fabric of the Cosmos: What is Space?" on pbs.com, and I couldn't help but wonder a few things after looking up some information about it. I find it funny that people have been using String Theory with only two dimensions (since they are supposed to keep adding dimensions...
  17. _maxim_

    Schematic for Holographic Projection

    Hi PF members, where I can find application notes for making a small Holographic Projector? I am looking for a schematic diagram of a small, compact and reliable Holographic Projector, based on LED or Laser emitter. I am completely new on this application, so let be as more exhaustive as...
  18. T

    Question: Greene's The Hidden Reality : the holographic principle

    Question: Greene's "The Hidden Reality": the holographic principle On pp. 260-261 of "The Hidden Reality" Brian Greene says the following: I puzzled over this for quite awhile and it seems as though Greene, probably inadvertently, phrased this somewhat more decisively than is justified - that...
  19. R

    Why no attribution to Bohm regarding holographic principles

    As I have seen, David Bohm was the exponent of the Holographic Universe and also the so called Holomovement. When Leonard Susskind gave a holograohic Universe solution to the information paradox, he did not credit Bohm. Nor does Lee Smolin in his book Quantum Gravity credit Bohm for saying...
  20. haael

    Holographic principle as an answer to few mysteries

    Some time ago I had finished the book "The Black Hole War" by Leonard Susskind. I was impressed about the idea of explaining 2 phenomenons as a consequence of the holographic principle. We all here know what the holographic principle is. The maximum amount of information in some region of...
  21. L

    Exploring the Holographic Principle: Questions and Answers

    Hi,I don't understand the holographic principle,how can the entire physics in a space be done on its boundary,arent we supressing a dimension and there by losing the information contained in it?,and is it neccesary that the boundary be closed?
  22. atyy

    Banks' Holographic Takeaway: Exploring arxiv.org/abs/1109.2435

    Why does Banks liken http://arxiv.org/abs/1109.2435" :confused: Is http://arxiv.org/abs/1108.5735" ? :rolleyes:
  23. C

    Lack of quantum fluctuations rules out holographic principle ?

    Recent searching of the light from the quasars indicate lack of the quantum fluctuation of the spacetime. http://arxiv.org/PS_cache/arxiv/pdf/1108/1108.6005v1.pdf Does it mean the lack of quantum foam rules out the discretness of the spacetime too ? How to explain Casimir effect and...
  24. D

    Holographic universes, information, and dark matter

    I am a physician not a physicist, but I read Brian Green, Susskind, Thorne, Gamow, etc. I recently learned of the Blue Brain project as well. It has occurred to me that dark matter may represent a two dimensional sphere surrounding each galaxy which holds the information for that galaxy. The...
  25. G

    Holographic projections onto the surface of a sphere

    I was reading the Scientific American latest edition and it was claimed that everything within the boundary of a particular timeframe volume can be described equally well by the projection of each event onto the surface. Is this accepted dogma? Suppose I picture (apparently I can't but...
  26. J

    Does the Holographic Principle Suggest a Schwartzchild Radius for the Universe?

    I understand that the holographic principle applies to black holes and states that they are objects of maximum information/entropy. It states further that this information/entropy is bounded by the black hole's area rather than its volume. Apparently the holographic principle might apply to...
  27. D

    Holographic disturbance in 3-dimensional calculations leading to CP Voilation

    Comrades, "The Holographic Interferometer, or Holometer, is a machine designed to test a particular idea about how space, time, matter, and energy behave on the very smallest scales." Its made to check up on the fuzziness of space that might come interfere with the propagation of light, so...
  28. C

    Mathematical model of holographic universe ?

    A light wave can be modeled by a complex number U which represents the electric or magnetic field of the light wave. The amplitude and phase of the light are represented by the absolute value and angle of the complex number. The object and reference waves at any point in the holographic system...
  29. Pengwuino

    Holographic principle and entropy mapping of a BH

    I've just started reading up on the holographic principle and eventually want to work my way to figuring out what Verlinde has proposed using it for. One thing I've noticed in a couple of papers is the mapping of the entropy of a black hole onto a holographic screen. Why are families of light...
  30. D

    How Does a Holographic Grating Work?

    Hi, I'm just trying to learn about how holographic gratings work. I see a bunch of examples that make use of a beam splitter, but I don't understand physically what a holographic grating is. Can anyone shed some light on this holographic grating? I'm hoping to have a more 3 dimensional...
  31. C

    Holographic Principle and missing Antimatter

    QCD does not violate the CP symmetry as easily as the electroweak theory; unlike the electroweak theory in which the gauge fields couple to chiral currents constructed from the fermionic fields, the gluons couple to vector currents. Experiments do not indicate any CP violation in the QCD sector...
  32. I

    Quantum Uncertainty in the Holographic Principle

    Hi all, A question about the Holographic Principle. I've recently started reading up about this, and watched Bousso's neat introductory video . I thought, "Ah, this is so refreshingly simple!", and proceeded to write down my own notes. However here things revealed themselves to be not...
  33. C

    The holometer - experimentally testing the holographic principle?

    "The holometer"-- experimentally testing the holographic principle? Several popular-science type news sources are reporting this weekend on an experiment at Fermilab that claims to experimentally test the holographic principle.. Popsci then says a bunch of vague stuff that sounds like they...
  34. R

    Sodium layer of atmosphere & holographic projection

    Hi guys, I recently read some stuff about satellites in space being able to project 3D images on to the sodium layer of our atmosphere about 60 miles above the Earth. Is this possible? Can the sodium layer potentially be used as a giant movie screen for projections? The stuff i read was about...
  35. inflector

    Holographic Dualities and the Potential Misdirection of String Theory

    In another thread: https://www.physicsforums.com/showthread.php?t=436080" a discussion came up relating to the validity of String Theory and the specific thought that, if nothing else, it has helped us to better understand the issues of quantum gravity. I wanted to start a new thread to adress...
  36. C

    Is Holographic Principle a confirmed theory ?

    Gerard 't Hooft proposes the dimensional reduction, Leonard Suskind uses the Holographic Principle in String Theory, Juan Maldacena wrotes AdS/CFT correspondence. There are hundreds articles in 2010 since Erik Verlinde wrote its "Origin of the gravity". Many astronomical phenomenons like Dark...
  37. P

    Understanding the Holographic Principle

    Hi, Today in a classical mechanics lecture, we were posed a question on whether there will be gravitational attraction between masses if the 2 masses were squashed into a 2D masses(so is flat). At first, i thought the force should still exist, since the force only depends on masses, so maybe...
  38. W

    Looking backwards through a holographic diffuser

    I know a diffuser should be approximately bidirectional, so the "direction" isn't the important part of the question. Our application is illuminating some light sensors while we test their electrical characteristics. Like CMOS image sensors for cell phones. Long ago, we used some plastic...
  39. C

    Entanglement and the Holographic principle

    Consider if you will... A pair of objects in an quantum entangled state. In such a state, observing the state of one object will determine the state of the other and thus the entangled system collapses. Therefor it seems that one object carries information about its entangled twin. A...
  40. M

    Has Holographic Display Technology Matured Abroad?

    Hello everybody, I am Chinese. Was pleased to find this site. As an Avatar, 3D is very popular in our country So I want to know, whether in foreign holographic display technology has matured Have no business case? I want to know the specific holographic imaging naked eye. Geographical...
  41. C

    Exploring the Holographic Principle: Space Recession and Inflation

    The observed expansion of the Universe is an example of the Holographic Principle. The galaxies escape from us not through the space but the space itself is carrying them away. Where comes the space (vacuum) from ? We know that in the holography there is an illusion of a spatial object...
  42. T

    Designing a Holographic Projector with Sound and Laser

    Greetings to all. In my first post, I'll present an idea based on acoustical holography. I intend to design a Holographic projector using sound and laser. The hologram is created by reflecting reference laser light on a vibrating diaphragm matrix. The diaphragms are vibrated by means of...
  43. tom.stoer

    Holographic / entropic approaches - why SU(2)?

    Let's forget about the history of LQG, that means let's forget about that it has been derived from GR in an appropriate formulation (Ashtekar variabes), let's forget about the constraints that had to be implemented; then we can simply use SU(2) spin networks as the starting point for a theory of...
  44. M

    Explaining the Holographic Principle - Physics & Math

    Can someone please explain the holographic principle to me? I'm decent in my physics and math, so you don't need to dumb things down too much :smile:
  45. S

    How is entropy defined by boundary area in Holographic Principle?

    Reference: http://en.wikipedia.org/wiki/Holographic_Principle The principle states that the description of a volume of space should be thought of as encoded on a boundary to the region, preferably a light-like boundary like a gravitational horizon. For a black hole, the principle states that...
  46. O

    Explore the Holographic Universe Theory

    Alright, well I'm new to this, so don't yell at me for not being very good. So I was reading about the Holographic Universe Theory and is it me or is it very depressing? I mean really...if that is the truth and the world is fake and imaginary, why would you ever actually want to tell...
  47. Z

    David Bohm's holographic paradigm of the cosmos

    Hi. I read a book about 2 years ago called The Holographic Universe, written by Michael Talbot. It described David Bohm's theory that the universe is like a Hologram. He describes all matter, and everything really, in an implicate order that we cannot perceive. The implicate order is like an...
  48. F

    Holographic Principle Research Paper

    Hello, I am doing a research paper for a final and I chose the holographic principle as my topic. Does anyone have any good sources, or information pertaining to this? Any help is greatly appreciated, thank you. P.S.- I have looked at some of the first links on google, and wikipedia
  49. S

    Is Holographic Quantum Computing the Future of Data Storage?

    After a decade or so in the lab, holographic data storage is about to burst into the hardware market big time. Its USP is that holographic data is stored globally rather than at specific sites in the storage medium. It is written using a pair of lasers to create an interference pattern...
  50. F

    Can underground pipes affect holographic interferometry results?

    We are attempting here at Illinois Wesleyan to create a holographic speckle-pattern inteferometer. We have been working at it for some time and have come to a roadblock in terms of picture quality. We're using a high quality optics table so there are no table vibrations. All of the mounts are...
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