1. Entangled Electrons

2. Electron probability cloud
 atomic orbital - describes the wave-like behavior of either one electron or a pair of electrons in an atom. This function can be used to calculate the probability of finding any electron of an atom in any specific region around the atoms nucleus. The term, atomic orbital, may also refer to the physical region or space where the electron can be calculated to be present, as defined by the particular mathematical form of the orbital

3. Quantum Superposition
Imagine a two ripples in a pond
When the ripples collide they can do different things
They can, cancel each other out, Make a bigger ripple, or a combination of both
On the quantum level, particles can be seen as waves
The difference is that in quantum particles, they can be in all three possible states at the same time
In quantum mechanics particles can be in two places at the same time, until measured then the superposition is lost and the particle is in one known state

4. Realism
Nature exist independently of the human mind. that even if the result of a possible measurement does not exist before the act of measuring it, that does not mean it is a creation of the mind of the observer
Locality – regular physics
An object is only directly influenced by its immediate surroundings. The concept is that for an action at one point to have an influence at another point, something in the space between those points (such as a field, wave, or particle) must carry the action. To exert an influence, something must travel through the space between the two points, carrying the influence.
Einstein and Team thought that Quantum mechanics might not be a local theory, because a measurement made on one of a pair of separated but entangled particles causes a simultaneous effect, the collapse of the wavefunction, in the remote particle (i.e. an effect exceeding the speed of light)
Relativity
Important to Einsteins understanding of Quantum theory, that the speed of light is the limit
Local Realism
Eisteins combination of both theories to explain the ERM paradox
Quantum Non Locality
A contradiction to Local Realism and the hidden variable theory that was proven by J Bell that states that simulations on a quantum level cannot be simulated by LHV theory

5. Copenhagen interpretation
any measurement of a property of a particle can be seen as acting on that particle (Schrodingers cat experiment)

6. All about spin
All fundamental particles have a property called spin, they aren’t actually spinning, but they have angular momentum, and an orientation in space.
We can spin a particle, but we have to choose a direction. It can either spin the direction of measurement or against it.
What weird is that measuring a particles spin changes its spin.
What does it mean to be entangled? It just means that the spin of the paired electron is opposite of the other one.
Entanglement arises naturally when two particles are created at the same point and instant in space

7. Spooky action at a distance
Published a paper with Boris Podolsky and Nathan Rosen in 1935 known as the EPR paradox (Einstein–Podolsky–Rosen paradox)
believed Bohr’s wave function was not a complete description of Quantum mechanics(because its logic defied the theory of relativity) – hence the paradox
He believed that when the particles were created, they somehow had stored data that would determine how the particles would react after becoming entangled. He called them Local Hidden Variables
Wasn’t called entangled electrons until much later. And Einsteins theory wasn’t proven wrong until later after Einsteins death.

8. John Bell The man who tested Einsteins hidden variable theory
He proved that the Local hidden variables theory didn’t work with quantum theory
Suck it Einstein
“God does not play dice with the universe” – A. Einstein
“Anyone who is not shocked by Quantum Theory, has not understood it” – N. Bohr

9. Can we communicate faster than the speed of light?
One thing that physicist agree is that it is impossible for us to communicate faster than the speed of light
Results at either detector are random and therefore when they meet up and compare notes, they are both random, but opposite of each other.

10. Quantum Key Distribution
“the science of exploiting quantum mechanical properties to perform cryptographic task.”
A unique property of it is that it can detect when a third party is trying to gain knowledge of the shared key. Because measuring quantum particles alters the state of the matter, the anomalies can be detected
QKD is only used to transmit a key, not to transmit data.
It can be combined with a standard algorithm for encryption to transmit data.

11. How can we use this for encryption?
If electrons (or any other quantum particle that can be entangled) become entangled, then it is possible to read the spin of the electrons as 1’s and 0’s
Electrons can be entangled over large distances by sending photons through fiber optic cable
Quantum dot arrays – a chip the size of a postage stamp that contains quantum dots or artificial atoms with just one electron. When excited, emit a single photon that is oriented to the electrons spin.
“An advantage of quantum dot arrays is that they could be produced using standard semiconductor-manufacturing technology. A single chip could contain millions of dots, arranged in a regular grid layout that would allow for the generation of long keys at high speeds.”

12. Spooky Acton at a distance
What is an Entangled Electron?
When 2 particles are created at the same instant from the same source, they become entangled. Entangling means that one particle has a “spin” that is oriented opposite of its counterpart. But quantum particles don’t actually spin, like light they behave like a wave and can be oriented so that the wave is on a single plane (polarization).
What is so great about this?
When Einstein learned about this phenomenon, he coined the term spooky action at a distance is that when you alter the spin of an entangled particle, it alters the spin of its counterpart.
Einstein VS Bohr
Einstein didn’t believe that the standing theory Bohr had created from Quantum Mechanics was complete. He thought that the fact that two particles no matter how far apart could react instantaneously, defied relativity because nothing can move faster than the speed of light. He believed that each particle had stored at separation that would determine how they would react to each other. He called it Local Hidden Variables.
Einstein proven wrong
About 30 years later, after his death. John Bell created an experiment that proved that Local hidden variables were impossible. Somehow particles that are entangled can interact instantaneously no matter how far apart.
Spooky Acton at a distance
How can we use this for encryption?
Since entangled particles can only spin with the angle of measurement or against it, this can be read as binary. (1’s and 0’s)
Electrons can be entangled over large distances by sending photons through fiber optic cable
Quantum dot arrays – a chip the size of a postage stamp that contains quantum dots or artificial atoms with just one electron. When excited, emit a single photon that is oriented to the electrons spin.
“An advantage of quantum dot arrays is that they could be produced using standard semiconductor-manufacturing technology. A single chip could contain millions of dots, arranged in a regular grid layout that would allow for the generation of long keys at high speeds.”
Quantum Encryption is unhackable?
A unique property of it is that it can detect when a third party is trying to gain knowledge of the shared key. Because measuring quantum particles alters the state of the matter, the anomalies can be detected
Quantum Key Distribution
QKD is only used to transmit a key, not to transmit data.
It can be combined with a standard algorithm for encryption to transmit data.
“God does not play dice with the universe” – A. Einstein
“Anyone who is not shocked by Quantum Theory, has not understood it” – N. Bohr

13. https://en.wikipedia.org/wiki/Principle_of_locality#Local_realism
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