triggernum5
- Joined May 4, 2008
- 216
Ok good then, its all squared away..
No I didn't say the mass of the photon is not zero.
I said the rest mass is zero.
What is the definition of a particle "at rest"?
Is that just a theoretical concept or can it actually happen under some circumstances?
/ ... JCD
Isn't all information and movement through space-time limited by the speed of light (when I say limited I should probably say always equal to)? As in... even photons need to travel through the universe at the speed of light implying that they can not travel it in an instant?Old thread, but...
On one side (particle) we have E=mc^2, on the other we have E= h(wave)
Therefore mc^2= h
So a photon of a given energy as expressed by h, will have a mass of h/c^2
Got it?
BTW, from the photon's perspective, they do get from the Sun to Earth in an instant. In fact, to put it in lay terms, photon's would belive they can cross the extent of the universe in an instant.
And this is why quantum mechanics and classical physics have yet to be combined. They say when we can finally combine them we'll have the theory of everything.There is a case, called entanglement, where two particles may be induced to carry identical spin states. If one changes state (usually as a result of deliberate observation), the other particle also changes. That change is apparently instantaneous - not limited by light speed.
Link to the Wikipedia article - http://en.wikipedia.org/wiki/Quantum_entanglement.
Yes, this is a facinating example of an instantaneous effect. One key thing about this is that this effect can not be used to instantaneously transmit information, matter or energy. You can do an experiment and compare the data later to show that the instantaneous effect happened, but no useful information is instantaneously transferred at the time of the experiment.There is a case, called entanglement, where two particles may be induced to carry identical spin states. If one changes state (usually as a result of deliberate observation), the other particle also changes. That change is apparently instantaneous - not limited by light speed.
Link to the Wikipedia article - http://en.wikipedia.org/wiki/Quantum_entanglement.
Stephan Hawking was able to combine QM and General Relativity in a very limited case at the edge of a Black Hole. Perhaps this is his greatest contribution to Physics. He predicted that Black Holes are not truely black and actually radiate energy (Hawking Radiation).And this is why quantum mechanics and classical physics have yet to be combined. They say when we can finally combine them we'll have the theory of everything.