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mee
Aug6-04, 03:07 PM
What exactly does the wavelength of a photon denote? Vibration, pulsation? Why does the smaller wavelengths connote higher energies? What is it about high energies that causes smaller wavelengths?

marlon
Aug6-04, 03:52 PM
A smaller wavelength corresponds to a higher frequency via the deBroglie-relations. This way of looking at a particle as if it were a wave is the basic property of QM. Just think of the amount of energy of a certain foton as represented by a wave with corresponding frequency.

mathman
Aug6-04, 06:47 PM
A simple way of looking at is E=hf, where E is energy, h is Planck's constant, and f is frequency. Frequency is inversely proportional to wavelength.

mee
Aug7-04, 11:38 AM
A smaller wavelength corresponds to a higher frequency via the deBroglie-relations. This way of looking at a particle as if it were a wave is the basic property of QM. Just think of the amount of energy of a certain foton as represented by a wave with corresponding frequency.

Thank you for showing what is the relationship, but why this relationship?

so-crates
Aug7-04, 03:30 PM
Thank you for showing what is the relationship, but why this relationship?

Remember that the speed of photons is the constant c. The speed of any wave is equal to the wavelength times the frequency, so c = lf. (l = lambda, the wavelentgth, f is frequency). Rearranging, f = c/l. If E = hf for a photon, then E = hc/l. So energy increaes with smaller l (wavelength).

Are you asking why c = lf, or why E = hf?

mee
Aug8-04, 11:12 AM
Remember that the speed of photons is the constant c. The speed of any wave is equal to the wavelength times the frequency, so c = lf. (l = lambda, the wavelentgth, f is frequency). Rearranging, f = c/l. If E = hf for a photon, then E = hc/l. So energy increaes with smaller l (wavelength).

Are you asking why c = lf, or why E = hf?

Sorry for my ignorance, but what is h and is time an integral part of f?

µ³
Aug8-04, 03:45 PM
Remember how light has properties of a wave (wave/particle duality)? Well that's what the wavelength is, the wavelength of the property aspect of the photon. This helps predict such outcomes as the interference pattern in double-slit experiments.

mee
Aug20-04, 11:34 AM
Remember how light has properties of a wave (wave/particle duality)? Well that's what the wavelength is, the wavelength of the property aspect of the photon. This helps predict such outcomes as the interference pattern in double-slit experiments.

But is this property a variable pulsation or a movement side to side through space or both?

selfAdjoint
Aug20-04, 01:09 PM
The EM wave is a transverse vibration. No longitudinal component has ever been observed.

sol2
Aug20-04, 10:05 PM
Thanks self adjoint.

Tidal Forces, Gravitational Waves

Gravitational waves are another example of how spacetime can be curved even in the vacuum. General relativity predicts that when any heavy object wiggles, it sends out ripples of spacetime curvature which propagate at the speed of light. This is far from obvious starting from our formulation of Einstein's equation! It also predicts that as one of these ripples of curvature passes by, our small ball of initially test particles will be stretched in one transverse direction while being squashed in the other transverse direction. From what we have already said, these effects must precisely cancel when we compute .

Hulse and Taylor won the Nobel prize in 1993 for careful observations of a binary neutron star which is slowly spiraling down, just as general relativity predicts it should, as it loses energy by emitting gravitational radiation. Gravitational waves have not been directly observed, but there are a number of projects underway to detect them. For example, the LIGO project will bounce a laser between hanging mirrors in an L-shaped detector, to see how one leg of the detector is stretched while the other is squashed. Both legs are 4 kilometers long, and the detector is designed to be sensitive to a -meter change in length of the arms.



© 2004 John Baez and Emory Bunn


http://math.ucr.edu/home/baez/einstein/node5.html

mee
Aug21-04, 12:39 PM
The EM wave is a transverse vibration. No longitudinal component has ever been observed.

I'm sorry but this doesn't answer my question very well. Could you explain a bit better? More details?