Is it possible for holograms, as in 3D projections of light in midair, to exist?   Consider this image. If a projector, placed in the same position as the gray circle in the first image, were to project some sort of light into the air, would it be able to form a three-dimensional image such as this bowl?
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Is there some law of physics that strictly prohibits the projection of 2D or 3D images into thin air (such as holograms in movies) or is a solution to achieve this still up for grabs by an eventual discoverer?
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I was wondering how far in imaging physics had gotten. Do we hold the technology to actually take a picture of, say, an alpha particle, or even a single atom?  I realise we aren't talking about camera pictures, so what kind of imaging techniques have taken images/is most likely to be the technique to take an image of a single atom?
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As of this writing it has been made clear to me that classical physics' Luminiferous aether was a terriblly poor discriptor of space. With the advent of Special Relativity and General Relativity, that aether ceased to be applicable. Today I began reading on the Higgs boson, and the Higgs field. How are those theories different from or similar to the seemingly irrational Luminiferous aether?  P.S. I am a first year student at Bakersfield Community College. If this question seems naive, you now have an explanation.  (EDIT) To me the similarity rests upon their fundamental influences regarding static positions in space. I currently only accept models in which static spacial positions are impossible. Contrastingly relative positions seem quite reasonable. In my humble opinion my naivatisms inhibit me from absorbing and understanding the Higgs boson. If they actually are similar, public protest would probably be more apparant. However, I have put forth my best effort to pose an direct question here.  P.S. The questions Where does space go when it falls? and What happens to time lost when matter accelerates? come much earlier in my studies, and they seem relevant.
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So I've been reading a bit and watching some videos about the double slit experiment, and therefore the wave particle duality; I've also read this "implies" that a particle can be in two places at the same time. Can you clarify this, and how could that be possible?
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In the images below, I have a cube that is sticking up about two thirds through a plane. But, despite the fact that the cube is not hovering over the plane, the shadow seems to indicate otherwise. How can I fix this shadow?
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I want to simulate blobs of water in a 2d game in Unity3d. One possible way of doing it is to use 3d  moving in a 2d plane though this is very processor intensive. Do you think it would be possible to make 2d metaballs, so I end up with a 2d meshes something like in the picture (In this case its 2 metaballs in conjunction) and then apply some kind of shader to make it look like they are bulging out and refracting the texture behind them like drops of water? I ask because I dont have much experience with shaders and am not sure what is possible.
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My goal is to create a realistic reproduction of a projector mounted on the ceiling. So far I can reproduce a projector that is projecting straight. But I cannot wrap my head around how to correct perspective distortion when the projector is tilted down. Edit: The Solution shoud work like you woud expect from a real world projector. With the light beam originating from the lamp position spreading out onto the surface and interacting with objects in between. For a projector that points 90° to the wall evything works fine.  As soon as i tilt the Projector i introduce Perspective distortion  Node tree to get the lamp to project a texture without barrel distorion  or   This example file:
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We're told that a real image is formed when light rays actually converge to a point. That's all good. But what happens if a screen isn't there to take the image on? Is it still there?
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i have a 3D Object and want to add a background image( if possible even a movie) to this 3D Object. I use Cycles to render and tried a plane with the  image as texture. When i go into render mode, it looks like this(picture with background) and when rendered, it has no background. The key also looks into  a different direction.  Should i even use Cycles for this or use motion tracking? i tried to use that but had several problems.     Rendered mode   When scene is rendered
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What does a light wave look like?   The only models I can seem to find online are 2D waves, they just look like sin() graphs.  I have seen the models of the two components of "light waves" (electric field and magnetic field) and they are represented on a 3D Cartesian coordinate system, but they are still just two 2D waves.    Surely light isn't really FLAT like this is it?   I guess I have always assumed it pules out in all directions greater then lesser as it travels, giving off the shape that you see during a sonic boom:    I have drawn what I picture to be a 3D model of the electric field of a light wave as it travels from left to right:   (cone image from: )  Is this an accurate representation of what the 3D radiation emitting from a light beam looks like, like a 3D wave?  (Obviously it would be more wavey, using a 3D cone graphic to create this diagram caused the edges to look spiked and sharp, a better object to use would have been something like a bullet (3D parabola) but I'm not the best with photoshop).    Also, if this is a somewhat accurate model of light wave pulsing in 3D, what does the magnetic wave look like in model form? Do they just overlap with possibly a slightly larger or smaller amplitude but the same maxima and minima locations along t (x-axis in my model)
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I'm a newbie with physics but I'm wondering how a ray of light can essentially be represented. I have always known that a ray of light proceeds in a straight line until it encounters another object (or material) that refracts/reflects it. But a light ray should be part of an electro-magnetic wave, is this correct? If it is so, it should obey to the  and this doesn't seem to me to describe a straight line ray.  I'm having problems visualizing how light is emitted and how it relates with the wave equation. Can someone with a clear understanding of the problem explain it to me in simple terms?
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How would I go a about making volume light beams?  I have have tried  various tutorials, but they must be for a older version. as applying them does seemingly nothing.  A link to a functioning tutorial would be greatly appreciated as well.  I don't have a picture or .blend to show, as my problem with atmospheric lighting does not pertain to any specific scene.
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Is there a material or render setting which makes the whole rendered image transparent at the spot of an object? I.e. not to create only a transparent object where the background is visible, but a transparent „hole“ with Alpha=0? I know that this can be achieved post-rendering by the Compositor and e.g. Cryptomatte, but I would like to define the transparent areas before rendering. Greetings from Germany, Tschöbbel
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How do lenses produce 2-dimensional images, if a lens bends all incoming rays of light to intersect at the focal point? Shouldn't this produce a single dot of light on a screen placed at the focal length?  This is basically the standard diagram that always shows up in textbooks:    I know this doesn't happen in real life--I used to use telescopes pretty frequently for work. The most in-focus image would be the one with the smallest diameters for the stars, which, of course, we think of point sources at infinity. But--the light from all stars (despite being at infinity) is not all focused at a single point. Instead, each star's light is focused at its own $(x,y)$ point on a 2D image.  I can't reconcile the theory as I understand it with any of my real-life experience with optics. What am I missing?
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The question pretty much sums up what I need to know. Why is it that light only gets dispersed into a spectrum when travelling through two non-parallel sides(like a prism) and not through something like a glass slide with parallel slides.  And how does this experiment(an experiment conducted by Newton) explain this? Because this is what is in my school textbook.
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Let's say you have the ability to shine some light into a perfectly round sphere and the sphere's interior surface was perfectly smooth and reflective and there was no way for the light to escape.  If you could observe the inside of the sphere, what would you observe? A glow? And would temperature affect the outcome?  Seems silly, it's just something I've always thought about but never spent enough time (until now) to actually find an answer.
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The first-ever image of a black hole released this week was taken with radio telescopes, suggesting that it is a  image and doesn't represent what a person would see in reality, or visible light. This seems to be confirmed by this , but I am perplexed as to why this is not widely mentioned, including the announcement on the telescope's  and Wikipedia (, ). Perhaps not mentioning it makes for better headlines, but it feels wrong.  What's going on here?