0.9k
1.1k
788
404
1kIs it fact or fallacy that the quantum mechanical probabilities of the micro cosmos are incompatible with the determinism of the macro cosmos.
Most scientist would agree the best way of accomplishing this would be to determine if one can be explained in terms of the other.
For example can one explain why many proponents of quantum mechanics assume that a particle simultaneously exists everywhere in space until it is observed or measured in terms of the classical laws that govern our macroscopic environment.
In Brian Greene book “The Fabric of the Cosmos: Space, Time, and the Texture of Reality” (Kindle Locations 1825-1836) he explains the difference between the probabilistic world of quantum mechanics and the deterministic world of Newtonian mechanics.
“According to Newton, if we knew in complete detail the state of the environment (the positions and velocities of every one of its particulate ingredients), we would be able to predict (given sufficient calculation prowess) with certainty whether it will rain at 4:07 p.m. tomorrow; if we knew all the physical details of relevance to a craps game (the precise shape and composition of the dice, their speed and orientation as they left your hand, the composition of the table and its surface, and so on), we would be able to predict with certainty how the dice will land. Since, in practice, we can’t gather all this information (and, even if we could, we do not yet have sufficiently powerful computers to perform the calculations required to make such predictions), we set our sights lower and predict only the probability of a given outcome in the weather or at the casino, making reasonable guesses about the data we don’t have.
However one of the most fundamental laws of classical mechanics is that each cause has a specific effect and that identical causes will have identical effects. However it also states that random causes will have random outcomes and that one can determine the probability of a certain event occurring based on the randomness of its cause.
Yet many feel that one cannot apply the concepts of Classical Newton physics to the quantum world because as Brian Greene points out in his book The Fabric of the Cosmos: Space, Time, and the Texture of Reality (Kindle Locations 1833-1836), “The probability introduced by quantum mechanics is of a different, more fundamental character (than classical Newton probabilities) Regardless of improvements in data collection or in computer power, the best we can ever do, according to quantum mechanics, is predict the probability of this or that outcome. The best we can ever do is predict the probability that an electron, or a proton, or a neutron, or any other of nature’s constituents, will be found here or there. Probability reigns supreme in the microcosmos.”
However if someone strikes a pool ball on a pool table in a dark room and cannot measure or determine initial conditions there is an extremely high probability that he will find it on the table when he turns on the light. However, he or she does not assume that the balls simultaneously exist on every point on its surface until the light is turned. Additionally one can apply Newton’s laws and the probability of the different initial conditions associated with that event to determine the final resting place of the pool balls on the table after the light is turn on. I think most would consider someone mentally deficient if he tried to convince us that the pool balls simultaneous existed every at every point on the surface of the pool table when the light off and only materialize when it was turn on just because he could not see how they got there.
Similarly why do some make the outlandish claim that a particle simultaneously exists in at every point in space and only materializes when it is observed based on the fact that they cannot “see” or measure the initial conditions and how they traveled to a specific point in space.
The reason is because quantum mechanics does not deal with evolution of a measurement but only with its outcomes. Therefore, because we in the macroscopic world and cannot “see” the initial condition responsible the evolution of a quantum system many assume that its entire history must be probabilistic.
However, as with the balls on a pool table the finial resting place of them and all quantum systems would be definable only in terms of the random probabilities of their initial conditions if one cannot “see” or determine them even if its evolutionary history conforms to Newton’s laws.
This shows how one can explain probabilistic outcomes of experiments in the quantum world in terms of the classical laws of the macroscopic world by assuming randomness of their outcomes is due to a lack of knowledge of their initial condition and not due the the probabilistic properties of their evolution.
Granted as Brian green pointed out nature may prevent us from ever develop the technology to precisely measure the initial conditions of a quantum system. However, as was shown above that does not means we cannot find an explanation of what we cannot see in the microcosmos in terms of what we can see in the macro cosmos.
In other words it is a fallacy to assume that the quantum mechanical probabilities of the micro cosmos lack or cannot be explained by the determinism of the macro cosmos.
Later Jeff
Copyright Jeffrey O’Callaghan 2013
0.9k1.1k7884041k