mcFreid
Reputation
2,391
Top tag
Next privilege 2,500 Rep.
Create tag synonyms
 Aug 3 awarded Yearling Oct 8 awarded Notable Question Sep 24 awarded Autobiographer Aug 3 awarded Yearling Feb 25 reviewed Approve Does the uncertainity principle violate the law of conservation of energy? Feb 23 reviewed Reject Does electron in wave form have mass? Feb 22 answered Soft brehmsstrahlung classical computation Feb 21 comment On the distinction of past and future: could one theoretically reverse direction of particles and cause time to appear to go backwards? I think you have the wrong expectation for your answer "it is possible". By the wording "it is", you seem to be thinking of a physical process that would reverse time. But that's not at all what the equations predict. What is true is that if you flip the sign of time (it's actually somewhat more complicated than that) and the sign of charge and then the sign of the spatial coordinates, the equations of physics will look exactly the same. That's all time-reversal means. Feb 21 comment Measurement of quantum state Ah, now I understand what you're asking. That is a good question and after thinking about it for a bit - I am not sure of the answer. I suggest making a new question on StackExchange titled something like "Is an ensemble of spin eigenstates equivalent to an ensemble of superimposed states?" Then ask the question you just asked in the comment above this one. Feb 21 comment Measurement of quantum state If I understand you correctly: you are asking whether an ensemble of spin eigenstates such that 50% of the ensemble is spin up and 50% of the ensemble is spin down is equivalent to a single particle in a superposition of spin up and and spin down? If that's your question, then the answer is no. An ensemble is many particles. A single particle is one particle. They are very different systems. Feb 21 reviewed Approve Are metals more heavy due to the Earth's magnetic field? Feb 21 reviewed Reject Defining electric potential energy Feb 21 comment Measurement of quantum state Yes, I know what a statistical ensemble is - I just don't see how that changes what I wrote. Feb 21 reviewed Approve Is time dilation real? Feb 21 answered Is time dilation real? Feb 20 comment Measurement of quantum state I don't understand your first sentence. As for a "hidden-variable"... That concept is in regards to the probablistic nature of quantum mechanics. Just because an observer lacks information in making a prediction does not mean there is some fundamental hidden variable in your theory. For example, if we tried to predict the orbit of Mercury yet didn't account for the small deviation due to Venus, this does not mean that the fundamental laws of gravity have a hidden variable. It just means we didn't account for all the interactions. Feb 20 reviewed Approve How to find the center of mass? Feb 20 answered What Does it Mean for an Extra Dimension to Have Size? Feb 20 reviewed Approve Energy of a damped oscillator Feb 18 reviewed Approve Eigenvalue spectrum of $L_x+iL_y$