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《金剛戰士》 Bonnie 有問題

在熊家,Bonnie問心如,“你可唔可以再解釋下量子糾纏呀,同埋點解呢個現象可以超越到光速喔。”

Quantum entanglement (量子糾纏), still under research, is a phenomenon that the quantum state (such as spin) of a pair of particles are linked, even if they are far apart. Knowing the state of one would tell you the state of the other for that same moment. Some may interpret that the quantum state of one is being transmitted to the other for synchronization with speed faster than that of light. Not quite...

Entangled particles are formed in linked pairs, kinda like twins. When you "detect" the state of one, you also know the linked state of the other. When one is disturbed at one place (such as in hacking,) so is the other far away. However, we don't know, for communication purposes, if we could systematically "change" the state of one and have that information received instantaneously by the other.

There's a difference between detecting linked information versus transmitting/receiving information.

發表於 Posted on: 2021-04-15 10:06

deepspace4
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Here's a thought experiment...
Imagine a solar system without Jupiter in it.
Then, suddenly, Jupiter "exists" in its place.

Jupiter would sense the presence of the Sun immediately because the pre-existence of the Sun already has curved spacetime to mark its presence. It is not that the news of the presence of the Sun is being transmitted to Jupiter at greater than light speed.

The Sun would not realize that appearance of Jupiter until after about 45 minutes. The existence of Jupiter would curve spacetime into a new form. It would take time for that information to be propagated to the Sun.

Entangled particles are formed as pairs. They then fly off in opposite directions at maybe light speed. It is postulated that the quantum state of one is being synchronized with the other because of their pre-existing inheritance that were established at the moment of their birth. It is not that the information is being transmitted from one to the other after they are far apart.

發表於 Posted on: 2021-04-17 2:31

deepspace4
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From Sunglasses to Entangled Photon pairs.

Light, behaves as photon particles at time, and electromagnetic waves at others. As particle, it is detected through the line of sight. However, when detecting through a restrictive gate, it emerges as a wave. (Ref. Double-Slit Experiment 雙縫實驗。)

Electromagnetic waves may be polarized into horizontal and vertical components. The vertical one would dive into water while the horizontal one would bounce off the water surface. The principle of polarized sunglasses is to reduce glares by blocking out the horizontal component that bounces off shiny surfaces.

One of several ways to generated entangled particles is by passing a stream of photons through a crystal. This parametric down-conversion process would, randomly, splitting certain high-energy photons into pairs of low-energy entangled photons, one vertically-polarized, the other horizontally. They are entangled as a result of conservation of energy/total momentum/angular momentum/etc.

發表於 Posted on: 2021-04-23 5:43

deepspace4
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Examining the position, momentum, spin, and polarization states of an entangled particle pair is not like watching a billiard ball match.

In quantum physics, an electron does not exist in any one particular location around the nucleus. Instead, it maybe spread out throughout the entire atom as matter wave, jumping between discrete energy shells. There is no guarantee that a particular incoming photon would hit an electron for exciting it to bounce between two energy shells and emitting low-energy photons in the process. And for the low-energy photons that get emitted, they could fly off in random directions. Only those pairs emitted in opposite directions, as correlated by the conservation of angular momentum, are in entangled state.

Detection of the entangled pairs are of equal randomness because of their matter wave nature. Examinations cannot be conducted individually. They can only be conducted in collections and correlated for statistical significance.

發表於 Posted on: 2021-05-03 5:14

deepspace4
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What good are entangled particles for?

A key characteristic of entangled particle pairs is that when one changes, the other would change correspondingly immediately. If one is able to construct a message with one set of the particles, that message would take form simultaneously with the entangled set residing elsewhere. There is a major obstacle though. At generation, the quantum states of the entangled particles are set randomly. Having no control over their states then, or later, there is no means of constructing meaningful messages with that.

What if we piggyback a set of the particles over an outgoing message while leaving its entangled set behind? When someone tries to hack into the message stream, the disturbance would make random changes to the states of the stream. The changes would be echoed instantly in the entangled counterpart. By monitoring for changes of the set left behind, we would be able to tell the moment if and when someone tries to hack into the message.

發表於 Posted on: 2021-05-10 6:20

deepspace4
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From entangled particles to synchronous fireflies, the holy grail to some maybe understanding how individual fireflies respond to their kin from variable distances or multiple flashes from different individuals

A loose swarm of fireflies will flash randomly. But, when the swarm reaches a certain density, the fireflies begin to blink in unison, with rhythmic, coordinated waves of light. The spontaneous synchronization of certain species of fireflies, such as the Photinus carolinus in the Great Smoky Mountains in the USA, has long baffled scientists.

Published recently in the journal Science Advances, scientists from U. of Colorado filmed the mating hordes of Photinus carolinus and mapped their flashing patterns in 3D space, obtaining evidence of the synchronized flashes of the insects. Further, it is found that the male fireflies did not flash instantaneously, but rather, in a cascading wave across the swarm much like schools of fish.

發表於 Posted on: 2021-07-08 8:34

deepspace4
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