Ask-a-Physicist by Topic
Quantum Mechanics
Does Einstein's relativity of simultaneity mean that two events cannot be simultaneous or that we cannot prove that two events occurred simultaneously?
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I have a question about waves and particles. Since waves and particles seem to be somewhat interchangeable at the subatomic level, at what wavelength does the wave / particle duality stop?
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As the nucleus gains mass by adding protons and neutrons does the size of the nucleus increase into the empty space of the atom or does the innermost orbital move away from the nucleus? Basically, is an atom of Ununoctium larger than an atom of Sodium? Find out the answer »
In the proton-proton chain reactions which happen, for instance, in our Sun, two protons collide and form a proton and a neutron. However, this just blows my mind.
What is the mechanism by which a proton simply loses its charge, becomes slightly more massive, and turns into a neutron?
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I am lost about neutrinos. I thought a neutrino was just a neutrino since it is neutral. What are the differences between electron, muon, and tau neutrinos? Find out the answer »
How was the universe created if physics states matter can neither be created nor destroyed? Find out the answer »
If the recent result of the tests of the speed of the neutrino are validated by other research groups what are its implications for the standard model of particle physics as it has been described to date?
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There seems to be a lot of debate about how accurately CERN measured the departure of their neutrinos. Could they not aim them at some other neutrino detector in the world and just use the difference in distance and time from the readings in Italy as this would eliminate the error in not knowing exactly when the neutrinos left CERN?
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When carrying out the double slit experiment using electrons or buckyball molecules, do the particles have to be traveling at near light speed velocities to produce an interference pattern?
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An electron beam, such as the one found in a TV picture tube, is composed of negatively charged electrons. Why is it that this beam does not rapidly spread out owing to the electric repulsion? I realize that the tube has various focusing magnets and such, but I would think the electronic repulsion would be a serious problem. - JT, Buffalo Grove, IL Find out the answer »
