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I thought quantum entanglement is the idea that two quantum particles separated by distance will behave the same at the same time regardless od distance. Why is sending photons over distances a verification of quantum entanglement? Can someone elaborate on what this is?
Wikipedia says: " If Bohmian Mechanics as an non-local hidden variables interpretation of quantum mechanics is accurate it should allow quantum computers to implement a search of an N-item database at most in O ( N 3 ) {\displaystyle O({\sqrt[{3}]{N}})} steps. This is slightly faster than the O ( N ) O({\sqrt {N}}) steps taken by Grover's algorithm using standard interpretations of quantum mechanics. Neither search m…
A staple of sci-fi has been a pair of boxes with quantum entangled particles inside allowing FTL communications once the boxes travel (sub-FTL) to their destination. By my understanding that's impossible, although I always wondered if you could coordinate FTL, by detecting when a particle was no longer entangled. Can someone with the background comment?
The trouble is you can't detect that. You can just make a measurement on your particle and get some result. That's the same whether it's entangled or not.
Could you use this for untraceable communication with hidden non-traceable submerged subs? That would be a military advantage.
I thought quantum entanglement is the idea that two quantum particles separated by distance will behave the same at the same time regardless od distance. Why is sending photons over distances a verification of quantum entanglement? Can someone elaborate on what this is?
The odd thing is it depends on the relative angle of the polarizers at the time the photons go through even if they are far apart. So if you use the analogy of God rolling a dice to determine if the photon goes through or not then He has to know the angle of the other polarizer in a faster than light way even if us mortals can not know that.
A staple of sci-fi has been a pair of boxes with quantum entangled particles inside allowing FTL communications once the boxes travel (sub-FTL) to their destination. By my understanding that's impossible, although I always wondered if you could coordinate FTL, by detecting when a particle was no longer entangled. Can someone with the background comment?
Caveat: I only have a B.Science degree in Engineering Physics (Colorado, USA) and hobbyist-type research in PhD-level physics. I've always found it easier to explain quantum entanglement thusly: Imagine you have 2 cubes that alternate glowing between purple and orange. And they stay in one color for a random amount of time (100s of milliseconds). Holding both in your hands, you would just have randomly color-shifting…
https://www.quantamagazine.org/quantum-entanglement-puzzle-s...
Earlier quoted context omitted.
Caveat: I only have a B.Science degree in Engineering Physics (Colorado, USA) and hobbyist-type research in PhD-level physics. I've always found it easier to explain quantum entanglement thusly: Imagine you have 2 cubes that alternate glowing between purple and orange. And they stay in one color for a random amount of time (100s of milliseconds). Holding both in your hands, you would just have randomly color-shifting…
i fail to see whats mysterious about knowing something without direct proof. You could put a literal orange cube in a box, ship it across the galaxy, and you'd "know" anyone opening the box would be an orange cube. You don't need to be present at the unboxing to know that with certainty. How is this different? Am I missing something?
To belabour the colours and boxes analogy:
We have 2 balls, if one is orange the other is always purple and vice versa.
Now these balls have an extra property. If you shake them vigorously they may or may not change colour randomly.
So, we put them in boxes without looking and take them far away from each other. Now, some time after they are far apart and before you look in the box, you shake one of the boxes. You then look.
In QM, if the ball you observe is orange(purple) then you know the other is purple(orange). But the other ball can't have known ahead of time that a) you were going to shake your one and b) that it changed colour (or didn't). That's why it's spooky.
Earlier quoted context omitted.
Caveat: I only have a B.Science degree in Engineering Physics (Colorado, USA) and hobbyist-type research in PhD-level physics. I've always found it easier to explain quantum entanglement thusly: Imagine you have 2 cubes that alternate glowing between purple and orange. And they stay in one color for a random amount of time (100s of milliseconds). Holding both in your hands, you would just have randomly color-shifting…
The "spookiness" is more subtle than that. You could argue that the cubes have decided on their color as soon as you close the box. Why doesn't this argument work for real quantum systems? In reality, you're not measuring colors of boxes, but spins of particles. You generate two particles with opposite spins along a known axis. If you measure the spins along that same axis, you always get the same result: one is spin…
The emphasis always seems to be on the "spookiness" of the observation, but the real trick is isolation and "entanglement" (pairing of values) in the first place.
Furthermore, nothing particularly real occurs at the time of observation, there's no way to tell that an observation of either of the particles has occurred, thus they aren't "tangled" as much encoded, isolated and separated.
Earlier quoted context omitted.
i fail to see whats mysterious about knowing something without direct proof. You could put a literal orange cube in a box, ship it across the galaxy, and you'd "know" anyone opening the box would be an orange cube. You don't need to be present at the unboxing to know that with certainty. How is this different? Am I missing something?
With quantum entanglement, what happens to one particle prior to measurement affects the other even if the effect occurred after they were parted. That's where it gets really spooky. To belabour the colours and boxes analogy: We have 2 balls, if one is orange the other is always purple and vice versa. Now these balls have an extra property. If you shake them vigorously they may or may not change colour randomly. So,…