I recently put a question to prof. Roberto Battiston of Trento University, who has just been nominated President of Italian Space Agency and he was kind enough to answer me in his blog at Le Scienze online magazine. Le Scienze is the Italian version of Scientific American, and I have been a visiting editor of it. The question was. if an hydrogen atom emits a photon, say in the Lyman-alpha emission, are they entangled? Yes, he answered, even if the hydrogen atom falls inside an event horizon (say a black hole). This is one of the mysteries of quantum mechanics, he said.
Tullio

That is some interesting stuff. I'm gonna go off into sci-fi for a second and ask: does that imply that we could drop an entangled particle into a black hole and "receive" info about the interior from the entangled partner? I'm assuming there is a way for us to get usable info from the entangled partner and i don't think we have that ability yet that's why i label this a sci-fi question.

There was an interesting paper on this subject by no less than Stephen Hawking, "Information Preservation and Weather Forecasting for Black Holes"
, talk given at the Kavli Institute for Theoretical Physics, Santa Barbara, August 2013, but I no longer have the link. I only have a hard copy, as I print the articles which interest me and have a pile of papers on my desk, not exactly the "paperless office".
Tullio

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Wasn't the information preservation supposed to be on the "surface" of the black hole's horizon? My question was intended to ask if we could get information about the interior of a black hole by dropping one partner of an entangled pair in and seeing the effects of the interior forces of the black hole on the partner that we kept outside of the event horizon. So we would "see" what was happening to the dropped in particle by observing it's brother out here. Which would be different than reading the information preserved on the event horizon. Am i making sense or is there a fundamental problem with my question (other that the facts that we can't get near a black hole or read usable info from the partner)?

Wasn't the information preservation supposed to be on the "surface" of the black hole's horizon? My question was intended to ask if we could get information about the interior of a black hole by dropping one partner of an entangled pair in and seeing the effects of the interior forces of the black hole on the partner that we kept outside of the event horizon. So we would "see" what was happening to the dropped in particle by observing it's brother out here. Which would be different than reading the information preserved on the event horizon. Am i making sense or is there a fundamental problem with my question (other that the facts that we can't get near a black hole or read usable info from the partner)?

I agree with you. Unfortunately, prof. Battiston has just been nominated to President of the Italian Space Agency and has informed us readers that he has no time to write again on his blog. I would have asked him the same question you are posing. Let's hope we can find someone to answer your question. I am 79, and, as you know, you can't teach new tricks to an old dog.
Tullio

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Two questions remain in my mind about the quantum entanglement/black hole question.

1. How do you tag your electron to know which one it is?

2. Would what's happening in or around a black hole cause the spin to change; if so how ?

Two questions remain in my mind about the quantum entanglement/black hole question.

1. How do you tag your electron to know which one it is?

2. Would what's happening in or around a black hole cause the spin to change; if so how ?

I don't have answers for either question that's why i asked. And especially your second question, i really don't know if what is happening inside the horizon would have any effect on the particle that we could observe.

Two questions remain in my mind about the quantum entanglement/black hole question.

1. How do you tag your electron to know which one it is?

2. Would what's happening in or around a black hole cause the spin to change; if so how ?

I don't have answers for either question that's why i asked. And especially your second question, i really don't know if what is happening inside the horizon would have any effect on the particle that we could observe.

We all don't know Andrew, that's the point in that case imo.

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rOZZ
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Le me try. Electrons have half-integer spin, so they must obey the Pauli exclusion principle. They cannot have the same quantum numbers. If one has spin up the other (if entangled) must have spin down. This is a tag to differentiate them.
If the electron inside the event horizon changes the direction of its spin, so must the one outside the event horizon. This AFAIK, if one younger user can give a better answer, let him try.
Tullio

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Le me try. Electrons have half-integer spin, so they must obey the Pauli exclusion principle. They cannot have the same quantum numbers. If one has spin up the other (if entangled) must have spin down. This is a tag to differentiate them.
If the electron inside the event horizon changes the direction of its spin, so must the one outside the event horizon. This AFAIK, if one younger user can give a better answer, let him try.
Tullio

Yes, that is the effect of entanglement. What we don't know is if there is a force inside the event horizon that would cause the e- to change spin. And if there is would the info escape the event horizon to affect it's partner on the outside.

Le me try. Electrons have half-integer spin, so they must obey the Pauli exclusion principle. They cannot have the same quantum numbers. If one has spin up the other (if entangled) must have spin down. This is a tag to differentiate them.
If the electron inside the event horizon changes the direction of its spin, so must the one outside the event horizon. This AFAIK, if one younger user can give a better answer, let him try.
Tullio

Yes, that is the effect of entanglement. What we don't know is if there is a force inside the event horizon that would cause the e- to change spin. And if there is would the info escape the event horizon to affect it's partner on the outside.

I would refer to Stephen Hawking for that:)

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rOZZ
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1. How do you tag your electron to know which one it is?

Therein lies an impossibility...

Supposedly, all electrons are indistinguishably identically alike apart from the properties of spin up or spin down and energy level.

Note that the Pauli Exclusion Principle requires all electrons to have a (even if only slightly) different energy level...


Keep searchin',
Martin

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See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

I don't think that they are required to have different energy levels: only that the quantum numbers must be different for two electrons in a single atom. It has to do with different orbits and only so many electrons can fit in each orbit and so on.

Of course there is no such thing as an electron as we envision it.

Le me try. Electrons have half-integer spin, so they must obey the Pauli exclusion principle. They cannot have the same quantum numbers. If one has spin up the other (if entangled) must have spin down. This is a tag to differentiate them.
If the electron inside the event horizon changes the direction of its spin, so must the one outside the event horizon. This AFAIK, if one younger user can give a better answer, let him try.
Tullio

Yes, that is the effect of entanglement. What we don't know is if there is a force inside the event horizon that would cause the e- to change spin. And if there is would the info escape the event horizon to affect it's partner on the outside.

I would refer to Stephen Hawking for that:)

Do you have a link to something that i would understand? Obviously his actual papers regarding the subject would be way over my head but maybe you know a link to an interpretation of his work that would help me.

I would search the Kavli Institute site for the talk delivered on August 2013 titled "Infprmation Preservation and Weather Forecasting for Black Holes". I no longer have the link.
Tullio

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I don't think that they are required to have different energy levels: only that the quantum numbers must be different for two electrons in a single atom. It has to do with different orbits and only so many electrons can fit in each orbit and so on.

I was thinking of what is seen for Lamb Shift (in QED).

However, is there not the assumption in Quantum Theory in that due to such as electrons being (potentially) able to 'hop' to anywhere in our universe, then the requirement for a unique energy level extends (potentially) across all electrons existing for our universe. (Note that as you go ever more distant, that difference in energy level can become ever smaller/finer...)

Of course there is no such thing as an electron as we envision it.

Indeed. They may be only a spooky disturbance of our fabric of space and time impinging in from effects from other smaller dimensions...


(The "Dungeon Dimensions"? To quote Terry Pratchett ;-) )


Keep searchin',
Martin

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See new freedom: Mageia Linux
Take a look for yourself: Linux Format
The Future is what We all make IT (GPLv3)

To the electron! May it be not useful to anybody! This was toasted at the Cambridge Cavendish Laboratory in 1897 after its Director, J.J.Thomson, had discovered the electron.
Tullio

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To the electron! Cheers!

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rOZZ
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To the electron! Cheers!

I thought you weren't going to vote. ;-)

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To the electron! Cheers!

I thought you weren't going to vote. ;-)

I vote Science my friend:) Cheers!

O oh, this is turning into the beer drinkers thread...

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rOZZ
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I would search the Kavli Institute site for the talk delivered on August 2013 titled "Infprmation Preservation and Weather Forecasting for Black Holes". I no longer have the link.
Tullio

Thanks! I found it and am looking over now. This is the pdf.

http://arxiv.org/pdf/1401.5761v1.pdf