According to the principles of quantum mechanics, when two particles are entangled, their properties become correlated in such a way that the state of one particle is intimately connected to the state of the other particle, regardless of the distance between them. This means that if you have a pair of entangled particles and you measure a property of one particle, the state of the other particle can become instantaneously correlated with the measurement outcome, even if it is located on the other side of the universe.
This phenomenon, known as quantum entanglement, has been experimentally verified through various tests and is considered a fundamental aspect of quantum mechanics. When the entangled particles are separated, the act of measuring one particle's property, such as its spin or polarization, can instantaneously "collapse" the state of the other particle to a correlated value, even if they are far apart. This correlation is maintained regardless of the distance between the particles.
The implications of quantum entanglement are still the subject of ongoing research and debate, and it is important to note that the exact mechanism of how the entanglement is maintained over large distances is not yet fully understood. However, experimental results have consistently shown that measurements on one entangled particle can have an immediate influence on the state of the other, regardless of the spatial separation.
It's worth mentioning that exploiting this instantaneous correlation for faster-than-light communication or sending information is not possible due to the no-communication theorem, which states that it is impossible to use entanglement to transmit classical information faster than the speed of light. However, the measurement outcomes on one side can be correlated with the measurement outcomes on the other side, providing a form of instantaneous correlation without transmitting information.
In summary, when you measure the properties of the first entangled particle, the properties of the second particle can become correlated with the measurement outcome, even if it is located on the other side of the universe. This phenomenon is a fundamental feature of quantum entanglement.