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A very basic Physics quest

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mkhan

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Hi Friends,

Is light wave or particle?

Cheers~

MAK
 

flatulent

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This has been the question for 80 or more years. There was a famous experiment a long time ago where a double slit interference pattern was done with such low light levels that only one photon every few seconds would go through a slit. The wave-like interference pattern resulted.

The question was, "How did each photon know about the other photons and select which part of the camera film to go to?"
 

Ignacius

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In an experiment about the light I and my team of research have verified a new phenomenon of interference of the light, that we have called "Interference of photons in the free space".
The design of optical bank and the new structure of photons are visible in: http://www.dnth.org/ (\Italiano\Ricerche scientifiche\Documenti\Interfernza fotonica nello spazio libero).
According to DNTH theory, the real photon is that showed above.
Sorry for my bad English. Ignacius.
 

paulys

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both of them. there is no other answer at the time.
 

electronicman

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the is both of them because the light has some wave and particle properities , it behaves like a wave somtimes and like particle in another time.

(this question takes a lot of physics get puzzeled for a long time until they convinced the light is both of them)
Thanks
 

anugrajiv

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light has a dual nature--both wave and particle

this was proved long back
 

m_pourfathi

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I believe from Quantum physics view, light is a mixture of energy and particle. It changes from one to another. So it gives it some properties of both concepts. I know it's a bit weird! It's just too abstract to be understood easily. But in terms of mathematics and Quantum physics it is completely understandable, It's hard to imagine the existence of a thing in such form! If you know the basics of Quantum Physics it will be easy for you to understand it.
 

KAEL41

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both is wave and particle is de duality of the ligh and one of the most amazing topics in the physics because is incredible.

the explanation is in a course osfphysicsIII and electromagnetic theory
 

JoKKeR

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light is both i guess they are moving by waves and also light is a photon. its a very basic particle, like electron i guess.

and yea light in moving in waves coz the length is what make us see it.
 

z_ghadiani

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nice and very common question.
Any one knows from quantum mechanics that all particles are waves also. But macroscopic particles are just a large scale approximation of quantum mechanical wave packets.
Thus my answer to your question is: Light is indeed wave and photon particles are just a macroscopic approximation of light.
 

donkey41

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hello there,

the wave nature of light is clear ..
but can anyone please tell me, why do we say that light (also) behaves like particles ?
which experiment did explain its particle nature ?

thx.
 

donkey41

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afaik, it has been observed that light has got its path bent when it has a very massive object near its path, object like a super massive star (or galaxy ?).
a dumb question for a physicist, but .. is this explanation enough to prove that light has a particle nature?
i mean, light got its path bent in refraction too !

black-hole thing seems enough to prove this theory, but if we forget the black-holes for a moment , then ?
 

halls

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donkey41 said:
i mean, light got its path bent in refraction too !

There is a little difference. Refraction happens when light propagation changes from one material to another one, thus changing the propagation velocity.

Light bending due to massive stars happen in vacuum, so propagation velocity doesn't change due to a medium change.
 

donkey41

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halls said:
There is a little difference. Refraction happens when light propagation changes from one material to another one, thus changing the propagation velocity.

Light bending due to massive stars happen in vacuum, so propagation velocity doesn't change due to a medium change.

i think, there is not always an absolute vacuum in space.

in the following is how i understand the bent of light path
space near a star or galaxy can be polluted with electrons, protons, neutrons, hydrogen atoms etc. etc.
we can safely call this a denser medium than absolute vacuum.
according to my understanding, that's the reason, why light gets 'bent' (because of my hypothetical polluted denser medium, whose density is changed proportionally with distance from star or galaxy) and not changes its path to a certain fixed angle in a straight line, like in a prism.

i can well be absolutely wrong .. please guide me.
 

laktronics

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Hi,
Yah, I think the photons are there every where in the universe, not only in the visible light, but in the whole range of Electromagnetic waves. I would like to call them 'EMtons' to generalise the name for the entire Electro Magnetic spectrum. They must be sticking to all basic particles including electrons and when they are released, they travel in groups as waves at the speed of light. The light waves carry photons just like waves in the ocean carry water molecules.

Regards,
Laktronics
 

omid110

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you must see quantum mechanics and modern physics books.
in some experiments, light acts as a particle (such as photoelectric effect, kampton effect ....) and it acts as wave in some experiments (such as diffraction)
So you must know your problem.
 

smab1176

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basically light waves are dual in nature and thus they are treated as waves in some cases and as particles in other cases like light is considered waves in the phenomenas like interference and diffraction and considered as particles in cases like photo-electric effect and Compton effect etc
 

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