Quantum weirdness; explanatory essay on particle/wave (Introduction)

by David Turell @, Tuesday, March 17, 2015, 23:54 (3539 days ago) @ David Turell

Explaining the recent finding of particle wave caught together:-http://www.realclearscience.com/articles/2015/03/17/debunking_medias_particle_physics_hype_109136.html-"To be precise, it's not strictly a light wave as the headlines suggest. It's actually a hybrid of a light wave, dancing on the wire, and an electromagnetic wave slithering on the wire's surface, produced by charged particles moving along the wire. They're kind of joined at the hip. This composite object is known as a surface plasmon polariton and you can read more about it on Wikipedia. -"For simplicity, let's consider it just to be a light wave. For the purposes of this discussion, it doesn't matter if the wave is made of photons or some hybrid object. It acts like a wave.-"But when the researchers fired electrons at the nanowire, the electrons sometimes sped up by specific amounts, indicating that they absorbed individual photons from the wire. How can light behave like both waves and particles at the same time?-"The answer is that the light was made of many different photons. Each of them behaved in a separate way. The researchers observed some photons acting like particles, and others acting like waves. Imaging both types simultaneously is what was done for the first time in their experiment. -
"Carbone mentioned a 2011 Science paper that he said came the closest thus far to capturing a single photon's dual nature. Researchers led by Aephraim Steinberg of the University of Toronto measured a particle-like property of individual photons — their average position - without destroying the wavelike interference patterns they later created. Physics World named this experiment the 2011 Breakthrough of the Year, and it was well deserved. However, even this experiment couldn't determine the exact positions of individual photons as they went on to create a wave-like pattern of light and dark bands on a detector.-"What is the fundamental reason for this limitation? It's something from quantum mechanics known as the Heisenberg uncertainty principle. Named for 20th century physicist Werner Heisenberg, it says that you can't measure two complementary variables, such as position and momentum, with complete precision. If you measure one precisely, it sacrifices the precision with which you can measure the other. -"So if you measure particle-like properties of the photon, it can sacrifice its wave-like properties. Zero in on a photon's position too precisely, and it cannot participate later on in creating a wave pattern.-"It is possible to measure some weakly wave-like and weakly particle-like properties in a photon simultaneously, Carbone said, as long as the combined uncertainties in the measurements do not violate the uncertainty principle."


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