such a light, enter through a single slit, it acts as a wave, but when you do not observe it but look at the results, it acts as a particle?
135296
Light has a dual nature. Or, better yet, it has a nature that depends on the observer.  The fantastic results of light experiments are fueling debates even now, half a century after quantum physics was born. I suggest you watch a movie called "What the bleep! do we know?  Or read books by Fred Alan Wolfe.
435506
Hmmmmmm, not entirely sure what you are on about here, so lets talk about the double slit experiment.\n\nFirst of all, I thought what was happening in the double slit experiment was DIFFRACTION and not refraction. Refraction occurs when light travels through mediums with differing densities.\nOk, so you have a monochromatic light source, lets say a laser. Now this must be done with monochomatic light, because we want the light to interfere with ITSELF, to produce the diffraction pattern. Now the slits in the experiment must have a width less than the wavelength of the light. If the slit was bigger, then the light would simply pass straight through the slit, and just produce a classical DOT on the screen. \n\nSo the incoming laser light, hits the slits. No here's the interesting bit. When light tries to travel through a hole that is too small, normally we would expect, that it just cant go through!!! But light is a tricky bugger, and DOES go through. The edges of the slit, cause the light beam to BEND!!! Now this might seem like refraction, however the bending occurs to the extent that the linear propogating wave, now acts as a point source at the slit!!!!!! Huh???? Well instead of the light looking like it came from a laser at the slit, the light now looks like it is coming from a monochromatic light bulb at the slit. So BOTH slits act as if there are TWO point sources of monochromatic light. Both these point sources are EXACTLY in phase with one another. You can imagine this as simulataneously dropping TWO pebbles into water, a foot apart. What you see in the water is two radiating ripple patterns. When the ripples hit each other, you get constructive (the waves add together), and also destructive (the waves subtract from one another, hence cancel) interference patterns. \nYou could sit down and play with the trigonometry of the situation, but lets keep the maths out of it. Draw on a piece of paper, two dots seperated by a distance. Now using a compas draw bigger and bigger circles around your dots. Keep the same radius increments for both dots. As you draw more circles you will see that you start to draw over the top of the circles from the neighbouring hole. Keep going draw lots of circles!!!!!! OK, now look at where your circles overlap and touch one another. You could draw a line connecting these points. In the middle of the slits/dots, you will notice that your circles overlap forming a straight line moving away from the slits/dots. This is the PRIMARY interference fringe!!!! To the left and right of the Primary are the secondaries, which are less intense.\n\nAnyway, the point is, that the light source needs to be monochromatic, and that the slits need to be smaller than the wavelength of your light.\n\nHmmmm, the above experiment was thought to be excellent evidence that light is a wave!!!! HOWEVER. This same experiment has been done firing individual photons at the same slits. What you see initially is just a dot which appears at some location on the screen. The next dot may be somewhere else. But over time, the dots still build up the SAME interference pattern. Without going into it in too much detail, this is an ODD result!!!!\n\nIn the end, this experiment suggests that interactions on these scales are determined by PROBABILTIES of how wave functions add, and subtract from one another. There are several possible outcomes that light can take upon emerging from the slits. The primary fringe has the highest probability, and thus, the majority of photons will hit this location. Thus this fringe is the BRIGHTEST. The spots that appear perpendicular (at right angles) to the slits, have the lowest probability, and thus are the weakest!!!!! If you wish to do this experiment yourself at home, simply get out your laser pointer, and shine it onto a CD or DVD, and reflect the beam onto a screen, or wall etc. The little pits on the CD act like the double slits in this experiment. Thus your ONE laser pointer, can turn into MA
405347
You must to review the diagram... note that the light escape in a second reflection, no in the first reflection.
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Actualy, I am an expert in this field, having a Ph.D. in Optical Sciences.\n\nI don't believe light is a particle, exactly.  It is a quantization of energy, but not really like a particle.  If it were a particle it would explain how it can propagate across nothingness.  The existence of something in space would just get into its way, so the nothingness only helps light to propagate.  But a particle implies rest mass and other physical properties which light does not have.\n\nI don't believe that empty space is something, contrary to the way some people interpret Einstein.\n\nI don't believe it is action at a distance.  Light takes a finite amount of time to cross space.  The action occurs where the light is.\n\nThe question was more of a problem when light was considered to be merely a wave.  A wave needed a medium to disturb or propagate across.  Sound moves molecules about as it propagates.  But light only bears a resemblance to a wave in the way it behaves.  It is not like a classical wave.\n\nThe best way I can think of to explain it is to understand that an electromagnetic wave carries with it its own medium.  The electric and magnetic fields oscillate, feeding on itself, so to speak.  The energy is launched into space and perpetuates itself according to the laws of physics.
162609
A photon will keep going until it gets absorbed.  By the essense of your question, I am guessing that you are thinking of photons in terms of a solid particle.  True, it can be thought of as a particle, that is part of wave-particle duality.  But the truth is, we cannot really understand wave-particle duality in an intuitive way.  The mathematics are well understood, but as humans we cannot really grasp, it does not make sense to our everyday experiences.  Don't think of it as a particle disappearing.  A photon is merely a means of transmitting energy.\n\nMaybe this will help:  An atom is in an energized state with an electron in a higher orbital.  The electron drops to the ground state and a photon is emitted.  That photon travels either 10 nanometers or one light year (doesn't matter) until it interacts with another atom of the same kind.  That second atom absorbs the photon and an electron gets excited to the same state as the electron in the orginal atom.  So in this sense a photon is just a means of transferring energy.  No matter is created or destroyed.
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I'd say option B. Each photon contains one fragment of the image. But actually, there are no such things as photon particles. The "waves" that "photon particles" create are actually part of the photon themselves.
78942
I beleive that the definition of a wave would be millions of particles moving through space/time. Thus the particle isn't the wave. The particle (+ millions more) make the wave. So you were correct in saying that the particle is traveling through space/time (+millions more) thus creating the waves as it moves.
219400
Wave-particle duality of light in particular is observed in a number of experiments but only one or the other form.  To show this you will to explain 2 or more phenomena, for matter the photoelectric effect is the best example for waves there are plenty to choose from.\n\nThat however is for light, if you are talking about matter for example electrons as a wave, then you will have to use debrogle equation and explain a experiment like electron diffraction, where is acts as a probablility wave and builds up a diffraction pattern rather that each electron actually being considered as a wave.\n\nHope this helps
548613
On the contrary, a light beam would merely percieve that it travelled instantly inbetween origin and destination. Space would be warped to Zero distance in the direction of travel, not Zero space. I know it seems like a sleight-of-hand trick with the mathematics, but the distinction is important.
503631
The experimental fact verified by experiments with light rays and mirror show that the happenings follow certain laws: If the light ray hits normally it comes back by the same path. If obliquely then it comes back obliquely equally inclined to the normal at the point of incidence and in the same plane of normal and the incident ray. But if you do experiment in which you also measure the intensity of light incident and reflected, then you find that the intensity of reflected light is slightly less. This shows that some light is either absorbed or scattered following no specific laws. Now this is the experimental fact. Now explanations. Explanation depends upon what you assume light to be made up of. If photons, then you know what happens to the table tennis ball when it hits the table without spinning. Same thing should happen to photons. That is how Newton explained  the phenomenon considering light as consisting of particles. He called them corpuscles. But photon is not an ordinary particle in bulk. It is supposed to have dual nature. Its total energy is equal h multiplied by some frequency which is a wave characteristic. Ordinary particle can have all velocities ranging from zero to velocity of light. But photons move with only one  velocity. So in case of bulky table tennis balls we say that they follow these rules of reflection which can be derived from mechanics but lose their little kinetic energy to the table and as sound. In case of photons this is not possible. So we say that if a bunch of photons are incident on a polished surface, there exists a maximum probability of following the laws of reflection, but the probability of the photon getting absorbed or getting scattered in any other direction is vey low but not zero. Similar expalnation can be thought of following the hypothesis that light is electromagnetic wave then we have to take the example of the mechanical waves and see how em wave is differen from them.
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Yes. Theoretically, if you try to determine the 'place' of a photon 'exactly' as if it is a particle, you will not be able to detect it's velocity. And when you want to know its 'exact' speed, you will have no idea about where it is, just like a wave.
521463
I believe the light bulb would light up the sphere, like a lamp shade, You'd see the light but not the light bulb. The metal particles that are in a one sided mirror allow some light to come through.
166889
according to the theory of quantum mechanics particles can exhibit a wave like behaviour, ie particles such as electrons which fundamentally are thought of as particles can infact difract and behave like a wave. for more info look up the wave-particle duality.
629893
I'm imagining that you're looking into a tube with the other end initially open, and then closing the other side.\n\nInitially, you can see light in the tube because photons are continuously streaming out from light sources, into the tube, and bouncing down towards your eye, all at the speed of light. You can observe this light because the photons are falling on your retina and being absorbed and recorded.\n\nWhen the light source is shut off, the photons currently within the tube -do indeed continue to bounce about the tube-, however, they will all quickly reach the end of thier journey, either absorbed as heat by the tube, or by your retina. \n\nImagine a cop looking for speeding cars on a stretch of highway. There is a traffic accident a few miles up the road, blocking all traffic. For several minutes, though, the officer will continue to observe the cars passing by him. After he has observed all the cars that got through before the accident, there will be no more cars observed until the accident is cleared away. If the cars were moving at the speed of light, the traffic would appear to drop to nothing (in this analogy, darkness) almost immediatley.\n\nThis is analogous to what you're seeing, but the difference is that the photons (usually) don't somehow escape, theier energy is absorbed over many, many collisions and reflections.
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3) Both\nThis phenomenon is called the "wave/particle duality of light"
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Light consists of elementary particles called photons.  A photon can have both particle and wave like properties depending on the observer.  In fact, a photon will have both properties until it is observed.
657067
Yes! in the Sub Atomic particle. Photons behave the same way.