Recent content by quantumphilosopher

I wondered the same thing. This is where the skill of the experimentalist comes in. Imagine a container full of particles ready to get out. And then you open the lid just enough for a particle to get out. I still worry that this may be more than just a practical problem. You're right. But it...

I did not propose this. Why do you think I did? Again, this is not what I described. I was explicit about the fact that the measurements are simultaneous. The fact that you are simply asserting the contrary is simply begging the question. Anyway, here's an even simpler setup aiming to obtain...

If I can obtain a precise value for both the position and the momentum of a single particle at a given time, then Heisenberg's uncertainty principle is false. I don't need to repeat the experiment. That's NOT what Heisenberg's principle is about!

Forget about measuring them 1 second after they left the source. I place a device that measures the particle's speed on the path of the particle, 1 meter away from the source. When the particle passes through the device I detect its speed. And I know its position (1 meter away from the source).

I'm measuring the position of one and the momentum of the other exactly at t=1s after the particles left the source. Are you suggesting measurement is a process that happens during a time interval? How much time can the measurement take?

I don't need to prepare it myself. I let Nature prepare it. In alpha decay the atomic nucleus emits simultaneously two protons (and two neutrons).

I agree it was badly phrased. I changed it. Tell me why if you know the answer.

1. What do you mean by "in sync" and "on the same course"? The EPR-type experiments confirmed that Bell's inequalities are violated. On many (most) interpretations of qm there is entanglement. 2. We can't exploit entanglement to send faster than light signals because quantum particles do not...

Heisenberg's uncertainty principle asserts a fundamental limit to the precision with which certain pairs of physical properties of a particle, such as position and momentum, can be known simultaneously. The more you know about one, the less you know about the other. Why does the following...

If the answer is no, why? Is it possible to show that, given the state spaces we have for individual particles, the singlet state is not a mixture of product states? If yes, how?

The Newtonian theory is strictly speaking false and it has been superseded by the theory of relativity. However, it is more simple and easier to apply than the theory of relativity. Also, in some situations, the results do not differ significantly. The question is: is the Newtonian theory still...

Are there any experiments which test special relativity? I know of the Kennedy–Thorndike experiment, but it involves light. I am curious whether a different kind of experiments showing relativistic effects like time dilation or length contraction have been performed (I'm thinking of experiments...

Are there any experiments which confirm special relativity? I know of the Kennedy–Thorndike experiment, but it involves light. I am curious whether a different kind of experiments showing relativistic effects like time dilation or length contraction have been performed (I'm thinking of...

Is the relativity of simultaneity relative? I've been thinking about this for a while and this is really troublesome... The short question: Why can’t we draw the conclusion that simultaneity is relative only when events involving light/electromagnetic radiation are considered? The...

Are there any other phenomena (optical or not) whose speed is constant and does not depend on whether the source is moving or not?