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Can someone explain the concept of Negative Probabilities in an intuitive manner? I can't seem to understand this concept. I hope someone can explain this concept in an intuitive manner.


marked as duplicate by ZeroTheHero, stafusa, John Rennie quantum-mechanics May 11 '18 at 14:58

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this my personal interpretation of negative probabilities, it defines negative probabilities against the concept of unitarity

1 ) negative probabilities violate unitarity ( unitarity is a 'conservation law' )

2 ) consequentially negative probabilities represent disappearing or newly appearing events or possible outcomes ( violation of conservation - inflow / outflow of quantities )

consider unitarity is defined for a six-sided dice ( cube ) each of the sides has $P = \frac{1}{6}$ unitarity is ensured by the fact that one of the six sides shows up in every throw

now consider the dice mutually changes its shape into an eight-sided dice ( octahedron ). The 'old' numbers 1 to 6 are still existent, however there are the newly appering events or outcomes 7 and 8. When considering that each of the sides still has $P = \frac{1}{6}$ ( this is the picture of the 6-sided dice transfered to the 8-sided ) unitarity is violated ( $\frac{8}{6}$ ) and negative probabilities occur. So in this picture these newly appearing events 7 and 8 have a negative probability against the previously defined set of 6 possible outcomes ( violation of conservation / unitarity )

the same can be said if the six-sided dice mutually changes into a four-sided dice ( tetrahedron )

note that this is my personal interpretation of negative probabilities, i am not sure if this is generally accepted...


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