Waves

[Ashish]

Whats the real concept behind a wave?

or just its an imaginary for proving certain theory.

[timo]

Try being a bit more specific, e.g.:

- What is a "real concept" ?

- Why do want to know ?

- Are you speaking about the most general/abstract definition of waves or of specific waves? In either case: Why do you think waves belong into the category "Modern and Theoretical physics" ?

[Ashish]

I mean to say that how a particle can exhibit a wave nature, according to DeBroglie's Equation

[swansont]

They really exhibit wave properties. You can make electrons, protons, neutrons, even atoms and molecules, interfere with each other.

[Ashish]

They really exhibit wave properties. You can make electrons, protons, neutrons, even atoms and molecules, interfere with each other.

Only to microscopic world

[insane_alien]

no, they exist in the macroscopic as well. everytime you walk through a door you form a diffraction pattern.

[Ashish]

no, they exist in the macroscopic as well. everytime you walk through a door you form a diffraction pattern.

Really nice

But how can you tell me that, If I assume it to be a shadow pattern which caused because some of the photons were blocked by my body ( not so because not yet proved)

[Edtharan]

no, they exist in the macroscopic as well. everytime you walk through a door you form a diffraction pattern.

Hmm... So if I walk through this door I might just destructivly interfere with my self and cease to exis...

[Klaynos]

you'd still exist, but you could only be detected in a limited range of places...

 

And you'd have to walk through 2 doors very slowly...

 

Buckminster fullerenes (clearly macroscopic things) have shown wave properties.

[thedarkshade]

Whats the real concept behind a wave?

or just its an imaginary for proving certain theory.

Well, the definition of what a wave is, is simple : Waves represent the spread of shaking in an elastic medium. And the spread of wave means nothing more than the transition of energy from one molecule to another.

 

They do exist, it is not an imaginary concept. Try ringing a bell in vacuum, you won't hear a thing! That's because waves need a medium. And depending on the medium they have different speeds. I have not heard of DeBroglie equation but the classical newtonian formulas for measuring the velocity of a wave in different mediums are:

 

[math]v=\sqrt{\frac{E}{\rho}}[/math] for solid medium where E is elasticity

 

[math]v=\sqrt{\frac{K}{\rho}}[/math] for liquid where K is compressibility

 

[math]v=\sqrt{\frac{p\gamma}{\rho}}[/math] for gases where [math]\gamma[/math] is Pauson's coefficient and has different values for single-atomic, double-atomic and triple-atomic molecules.

 

Cheers,

Shade

[Klaynos]

EM waves don't require a medium.

[swansont]

Neither do deBroglie waves.

[thedarkshade]

But they're still waves, they can't just move through nothingness!

[ydoaPs]

But they're still waves, they can't just move through nothingness!

 

Sure they can. That's what it means to require no medium. How do you think light gets here from the sun?

[Ashish]

Well, the definition of what a wave is, is simple : Waves represent the spread of shaking in an elastic medium. And the spread of wave means nothing more than the transition of energy from one molecule to another.

 

They do exist, it is not an imaginary concept. Try ringing a bell in vacuum, you won't hear a thing! That's because waves need a medium. And depending on the medium they have different speeds.

 

 

Try ringing a bell in vacuum, you won't hear a thing! That's because waves need a medium. Can I assume that since there is vaccum ( a low pressure or a very less number of particles or matter), hence there are no particles thats why we are unable to hear i.e. there is nothing like a wave but we assume.

 

EM waves don't require a medium.

 

I have studied that EM waves have both electric and magnetic field components. These components oscillate at right angles to each other and to the direction of propagation, and are in phase with each other.

 

Since light is an electromagnetic wave, it is not affected by travelling through static electric or magnetic fields in a linear medium such as a vacuum. In nonlinear media such as some crystals, however, interactions can occur between light and static electric and magnetic fields - these interactions include the Faraday effect and the Kerr effect.

[thedarkshade]

Sure they can. That's what it means to require no medium. How do you think light gets here from the sun?

Ah I see! So from this point of view we have waves that require medium (like sound waves) and waves than do not require a medium (EM). Cool, I've never seen this in any textbook!

[Klaynos]

In nonlinear media such as some crystals, however, interactions can occur between light and static electric and magnetic fields - these interactions include the Faraday effect and the Kerr effect.

 

My current research is actually concerned with the Kerr effect.

 

And the waves (photons) themselves do not get effected by the magnetic field, but the electrons which absorb and re-emit the photons are effected, and this results in a modified wave leaving the material...