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>"Because the two photons appear to communicate faster than the speed of light — something prohibited by his theories of relativity—this phenomenon deeply troub

>"Because the two photons appear to communicate faster than the speed of light — something prohibited by his theories of relativity—this phenomenon deeply troubled Albert Einstein, who dubbed it “spooky action at a distance.” These concerns remained theoretical until the 1960s, when physicist John Bell devised a way to test if reality is truly spooky—or if there could be a more mundane explanation behind the correlations between entangled partners." [...] Such “Bell tests” have since been carried out, with a series of watertight versions performed in 2015, and they have confirmed reality’s spookiness." Logic: If you believe that the Bell Test is correct -- you must equal-and-oppositely believe that the speed of light is NOT the upper limit of speed in the universe, that is, that Faster-Than-Light (FTL) speeds are possible. Conversely, if you believe that speed maxes out with the speed of light, and that nothing can travel faster than the speed of light -- then you equal-and-oppositely believe that the Bell Test is wrong. But, you cannot believe that nothing can travel faster than the speed of light AND that the Bell Test is correct, simultaneously -- as this would result in a logical paradox... (Choose one, but not both at the same time...)

AnotherGoodName 6y ago
The trick is to talk in terms of communicating information faster than the speed of light. Both relativity and quantum theories agree that there's no communication of information faster than the speed of light. Two wave-functions collapsing to opposite states lightyears away doesn't actually allow two people to communicate in an FTL way.
- Lichtso 6y ago
  Exactly, so it becomes a question of the very inner working of the universe itself: How does the universe spontaneously assign the states consistently without communicating and also without assigning the states beforehand. This is precisely why the experiment was proposed, to show this conflict in our understanding of the constraints.
  - 3pt14159 6y ago
    If one bends a piece of paper such that two faces nearly meet then pokes a pin through the page and makes two holes in the page essentially simultaneously from the perspective of the two dimensional beings on the page it appears that the two events happened far apart and that "something must be moving information at faster than the speed of light" when the reality is more complex. That's how I mentally think about entanglement. I doesn't need to operate through the universe as I understand (or operate within) it.
kinghajj 6y ago
> If you believe that the Bell Test is correct -- you must equal-and-oppositely believe that the speed of light is NOT the upper limit of speed in the universe, that is, that Faster-Than-Light (FTL) speeds are possible. That's not exactly correct, you just have to forgo locality, which some interpretations of quantum mechanics do, like the Bohmian one. Like the sibling comment points out, this still doesn't permit faster-than-light communication.
- peter_d_sherman 6y ago
  >"That's not exactly correct, you just have to forgo locality, which some interpretations of quantum mechanics do, like the Bohmian one. Like the sibling comment points out, this still doesn't permit faster-than-light communication." Er, yes, but, forgoing locality -- changes the definition of speed -- because it changes the definition of distance: Speed = Distance / Time If you forgo locality, then you are now able to modify distance in this equation, that is, your equation now looks like this: Speed = ((Distance * NON_LOCALITY_SCALING_FACTOR) / Time) That's because, let's say you have a black hole/quantum entangled particle/stargate/thing A at one point in the universe that immediately influences thing B at some distance to it in the universe (call this "connected" concept by whatever name or metaphor you will), etc. Well, if so, then the NON_LOCALITY_SCALING_FACTOR is there to adjust the shorter distance to the longer one. Like let's say you had a stargate linking two points in the universe, and you walked 10 feet into it, but this 10 feet, after you had walked it, resulted in you appearing halfway across the universe. OK, so that's 10 feet in local movement, in local distance, but billions of miles of actual (but non-local) distance. That's why you now need NON_LOCALITY_SCALING_FACTOR in your equation, because you've redefined Speed in terms of it. But, by redefining Speed (which must occur, by forgoing locality!), you now have agreed (because it is implied) that anything faster than light (communication, travel etc.) can now occur, that is -- all you need is a high enough NON_LOCALITY_SCALING_FACTOR in the equation for speed -- which you get by forgoing locality...
bmh100 6y ago
Leonard Susskind said that quantum entanglement between particles equivalent to a wormhole between black holes [1]. The collapse still propagates at the speed of light across the bridge. [1]: https://www.youtube.com/watch?v=OBPpRqxY8Uw https://www.youtube.com/watch?v=OBPpRqxY8Uw
- aeternum 6y ago
  Thinking about it as a collapse used to be the most popular interpretation, but it really complicates more than it solves. All the experiments become much clearer if you think of everything behaving primarily as a wave (all possible paths are taken). A particle is just a special (limited energy) case of this where all paths are still taken but since there is limited energy only one path can be 'registered', and this happens probabilistically.

AnotherGoodName 6y ago

The trick is to talk in terms of communicating information faster than the speed of light. Both relativity and quantum theories agree that there's no communication of information faster than the speed of light. Two wave-functions collapsing to opposite states lightyears away doesn't actually allow two people to communicate in an FTL way.

Lichtso 6y ago
Exactly, so it becomes a question of the very inner working of the universe itself: How does the universe spontaneously assign the states consistently without communicating and also without assigning the states beforehand. This is precisely why the experiment was proposed, to show this conflict in our understanding of the constraints.
- 3pt14159 6y ago
  If one bends a piece of paper such that two faces nearly meet then pokes a pin through the page and makes two holes in the page essentially simultaneously from the perspective of the two dimensional beings on the page it appears that the two events happened far apart and that "something must be moving information at faster than the speed of light" when the reality is more complex. That's how I mentally think about entanglement. I doesn't need to operate through the universe as I understand (or operate within) it.

kinghajj 6y ago

> If you believe that the Bell Test is correct -- you must equal-and-oppositely believe that the speed of light is NOT the upper limit of speed in the universe, that is, that Faster-Than-Light (FTL) speeds are possible. That's not exactly correct, you just have to forgo locality, which some interpretations of quantum mechanics do, like the Bohmian one. Like the sibling comment points out, this still doesn't permit faster-than-light communication.

peter_d_sherman 6y ago
>"That's not exactly correct, you just have to forgo locality, which some interpretations of quantum mechanics do, like the Bohmian one. Like the sibling comment points out, this still doesn't permit faster-than-light communication." Er, yes, but, forgoing locality -- changes the definition of speed -- because it changes the definition of distance: Speed = Distance / Time If you forgo locality, then you are now able to modify distance in this equation, that is, your equation now looks like this: Speed = ((Distance * NON_LOCALITY_SCALING_FACTOR) / Time) That's because, let's say you have a black hole/quantum entangled particle/stargate/thing A at one point in the universe that immediately influences thing B at some distance to it in the universe (call this "connected" concept by whatever name or metaphor you will), etc. Well, if so, then the NON_LOCALITY_SCALING_FACTOR is there to adjust the shorter distance to the longer one. Like let's say you had a stargate linking two points in the universe, and you walked 10 feet into it, but this 10 feet, after you had walked it, resulted in you appearing halfway across the universe. OK, so that's 10 feet in local movement, in local distance, but billions of miles of actual (but non-local) distance. That's why you now need NON_LOCALITY_SCALING_FACTOR in your equation, because you've redefined Speed in terms of it. But, by redefining Speed (which must occur, by forgoing locality!), you now have agreed (because it is implied) that anything faster than light (communication, travel etc.) can now occur, that is -- all you need is a high enough NON_LOCALITY_SCALING_FACTOR in the equation for speed -- which you get by forgoing locality...

bmh100 6y ago

Leonard Susskind said that quantum entanglement between particles equivalent to a wormhole between black holes [1]. The collapse still propagates at the speed of light across the bridge. [1]: https://www.youtube.com/watch?v=OBPpRqxY8Uw https://www.youtube.com/watch?v=OBPpRqxY8Uw

aeternum 6y ago
Thinking about it as a collapse used to be the most popular interpretation, but it really complicates more than it solves. All the experiments become much clearer if you think of everything behaving primarily as a wave (all possible paths are taken). A particle is just a special (limited energy) case of this where all paths are still taken but since there is limited energy only one path can be 'registered', and this happens probabilistically.