Tag Info

New answers tagged

1

Let us start from the beginning. Elementary particles are quantum mechanical entities. They can be described with the quantum mechanical solutions of the appropriate equations for the set up under consideration with the constants taken from the boundary conditions of the problem. In this it is not different than the situation with classical mechanics ...


1

There are a few misconceptions in your scenario that cause the misunderstanding. First of all, by definition, causality means that if the time interval between two events is positive in one reference frame, then it is positive in any other reference frame of your choice and viceversa, provided the velocity the events propagate to be smaller than $c$. If, on ...


-1

There have been conducted many experiments in which light impulses travelled faster than light Are you aware of any scientific publication on major journals officially acknowledging such event? As far as the scientific community knows, there is no such evidence. Even though there were any, this would have nothing to do with quantum entanglement anyway, ...


0

A measurement is an interaction that allows some information about a quantum system to be copied. (The information that can be copied is something like the value of one particular observable or POVM, not the whole state.) An entangled state is just a state that can't be written as a product of the state of each system. So $|a\rangle_1|a\rangle_2$ is not ...


0

the outside of the bubble is causally disconnected from what happens inside the bubble. So that means that the space around the bubble doesn't even know there is a bubble. Even if you had the exotic matter to do the trick, you would have to lay it out as a cylinder between home and destination before you can make the trip. So, as an interstellar propulsion, ...


2

There is no such thing as "rotational speed". There is angular momentum, which has units of $\frac{\mathrm{kg} \cdot \mathrm{m}}{\mathrm{s}}$ (and so is not a speed), and angular velocity which has units of $\frac{1}{\mathrm s}$ (and so is not a speed either). There is no maximum angular velocity in special relativity. So long as $\omega r\lt c$ (the ...


6

Nope, not an exception. A stick, like any solid object, is essentially a bunch of atoms held together at a particular equilibrium distance. Atoms of a solid are pretty well modeled by a lattice of spheres connected by springs (with damping). What actually happens when you hit one end of a stick, is that you compress the surface atoms inwards towards their ...


2

If you punch one end, the atoms at that end are displaced. They push the neighbouring atoms, who push their neighbours etc. This "push" comes in the form of an increase electric field, because the atoms get closer. Such changes in electric field propatages with the speed of light. So if you could move an atom close to another atom instantaneously, then the ...


1

Actually we can't reach to a thing that is more speeder than light. Because as we read in the Einstein's theory, the speed of light is constant. When you reach the speed near the speed of light, the time will be stretched, and more you get close to the speed of light, more the time will be stretched and YOU WILL NEVER GET TO THE SPEED OF LIGHT. So, due to ...


2

This answer here covers the general case where the aisle of the bus you run up, so your velocity, is not necessarily collinear (parallel) to the velocity of the bus relative to Earth. Let define the velocities : \begin{equation} \text{(1) Velocity of bus relative to Earth : } \qquad \mathbf{v}=\upsilon \;\mathbf{n} \tag{A-01a} \end{equation} ...



Top 50 recent answers are included