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**Physics, Astronomy & Cosmology / Re: Is uniqueness conserved?**

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**Today**at 01:06:03 »

The confusion arises from the assertion of "specific coordinates". The relationship between any two events is a unique vector in spacetime, but that vector can be mapped onto any coordinate system you choose, including the possiblity of degeneracy if the extended vector passes through the origin of that system.

To give an example, suppose galaxy A explodes and emits a pulse of gamma radiation. After a thousand years, that pulse triggers the explosion of galaxy B which just happens to have moved into such a position that its gamma burst is indistinguishable from that of A at the time they both reach Earth. Having no other information, our observer can only conclude that there has been at least one explosion, somewhere in the direction of B, whereas an observer on Pluto would know that there were at least two explosions 1000 light years apart.

Time to resurrect the abbreviated version of the Patagonian Cows. Three blokes in a train see two cows in a field.

Politician: "The vast majority of Patagonian cows are black"

Statistician: "On a possibly insufficient sample, the Bayesian postulate is that half the cows in Patagonia are black"

Physicist: "I saw two bovine quadrupeds, at least one side of one of which was black."

To give an example, suppose galaxy A explodes and emits a pulse of gamma radiation. After a thousand years, that pulse triggers the explosion of galaxy B which just happens to have moved into such a position that its gamma burst is indistinguishable from that of A at the time they both reach Earth. Having no other information, our observer can only conclude that there has been at least one explosion, somewhere in the direction of B, whereas an observer on Pluto would know that there were at least two explosions 1000 light years apart.

Time to resurrect the abbreviated version of the Patagonian Cows. Three blokes in a train see two cows in a field.

Politician: "The vast majority of Patagonian cows are black"

Statistician: "On a possibly insufficient sample, the Bayesian postulate is that half the cows in Patagonia are black"

Physicist: "I saw two bovine quadrupeds, at least one side of one of which was black."