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Determining wavelengths of macroscopic objects?

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From what I understand the wavelength of an object is given by: Planks constant/Momentum.

Does this mean that when stationary(relatively) that particles have no wavelength and are therefore not waves? If so, why does a particle need to be moving to have a wavelike character?

I have the feeling there is a simple answer but I would be grateful if it's cleared up, thanks.

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From what I understand the wavelength of an object is given by: Planks constant/Momentum.

Does this mean that when stationary(relatively) that particles have no wavelength and are therefore not waves? If so, why does a particle need to be moving to have a wavelike character?

I have the feeling there is a simple answer but I would be grateful if it's cleared up, thanks.

Compton's wavelength?

You can derive it by dividing through $Mc^2$ into $\hbar c = GM^2$. Photon's can never be at rest , however, as I understand the wavelnegth the energy of a photon can be low enough to have it's wavelength match any particle who is at rest near rest. So the wavelength may be seen perhaps, as the energy of the wave of a particle at near rest which may fit the energy of a photon whose energy is small enough.

Edited by Aethelwulf
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Compton's wavelength?

You can derive it by dividing through $Mc^2$ into $\hbar c = GM^2$. Photon's can never be at rest , however, as I understand the wavelnegth the energy of a photon can be low enough to have it's wavelength match any particle who is at rest near rest. So the wavelength may be seen perhaps, as the energy of the wave of a particle at near rest which may fit the energy of a photon whose energy is small enough.

Thanks for the reply, I was referring moreso to when I read on the internet and people give wavelengths to things like tennis balls and actual macroscopic matter. Even though we can't see the wavelike properties(another thing I don't know why) they still have a "wavelength". Does this wavelength no longer exists if said particle has 0 momentum?

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Thanks for the reply, I was referring moreso to when I read on the internet and people give wavelengths to things like tennis balls and actual macroscopic matter. Even though we can't see the wavelike properties(another thing I don't know why) they still have a "wavelength". Does this wavelength no longer exists if said particle has 0 momentum?

That's right.

Even you have a wavelength, but it is very small. So it still exists... very technically speaking, you have a wave function which extends way past the milkyway. All macroscopic objects have wave functions, but as I said, they are too small to be visible.

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That's right.

Even you have a wavelength, but it is very small. So it still exists... very technically speaking, you have a wave function which extends way past the milkyway. All macroscopic objects have wave functions, but as I said, they are too small to be visible.

That is an awesome thing to comprehend, thanks.

you're welcome.

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There is some great info here related to wave-theory and quantum mechanics plus other stuff, it's well worth checking out http://www.youtube.com/user/physicsacademy

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There is some great info here related to wave-theory and quantum mechanics plus other stuff, it's well worth checking out http://www.youtube.c.../physicsacademy

Thanks for the link.

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That's right.

Even you have a wavelength, but it is very small. So it still exists... very technically speaking, you have a wave function which extends way past the milkyway. All macroscopic objects have wave functions, but as I said, they are too small to be visible.

The deBroglie wavelength is not the same thing as the wave function.

From what I understand the wavelength of an object is given by: Planks constant/Momentum.

Does this mean that when stationary(relatively) that particles have no wavelength and are therefore not waves? If so, why does a particle need to be moving to have a wavelike character?

Note that as momentum tends toward zero, this corresponds to a wavelength going to infinity, which is not the same as no wavelength. But you really don't have the possibility of momentum actually going to zero.

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All macroscopic objects have wave functions, but as I said, they are too small to be visible.

A cat has not wavefunction. The moon has not wavefunction...

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The deBroglie wavelength is not the same thing as the wave function.

I know that.. Perhaps I should have made a distinction. I was just trying to get him to mull over other things as well.

A cat has not wavefunction. The moon has not wavefunction...

Can you rephrase this... are you saying, does a cat not have a wavefunction, or are you implying it does not have one?

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