The discovery of de Broglie about the wave nature of particles has an associated new phenomenon in the classical world of common sense, it is surprising and counterintuitive principle.
was Werner Heisenberg (1901-1976) who came to him, but in a completely different way. Until then, the development of mixed quantum classical physics, with the addition of quantum principles, the result of experimental results. However, a full understanding of nature requires a broader theory, which is deducted from these postulates, we must develop a quantum mechanics.
classical mechanics of Newton's three laws. From these, it is possible to describe any situation, and come to an equation of motion, ie to solve an equation that gives the time evolution of the system studied. This system applies both to describe the oscillation of a spring, as the orbit of a planet around the Sun
Quantum mechanics tries to do exactly the same thing from a common point that is able to describe the evolution of any system at the quantum level. Instead of treating each system owners (photoelectric effect, Compton effect, electron diffraction, the Bohr model for the orbits), it is to get the general behavior of any system based on a certain basis.
The development of these mechanics, Heisenberg came to a rather surprising mathematical result. The development included some mathematical operations that represent the experimental observation of the system. The result was that if you made two comments, for example, the position and angular momentum, the order in which it influences the final result. Mathematically, if an observation A, and one B, this meant that A • B is different from B • A . In fact, its ( A • B - B • A ) is a complex number. This result occurs only for certain amounts related, such as position and momentum, or energy and time.
From the school we are taught that multiplication is commutative. However, this is true when we talk about numbers . When it comes for example, matrices, then this property is not insured. This is how the mechanics of Heisenberg is based on matrix algebra, and hence the development of Heisenberg matrix mechanics call him .
Although mathematically it is possible to understand that A • B is not equal to B • A , what is the point that in the real world? implies that the order in which they performed a measure influences the final result . One can measure the position of a particle with a given accuracy. However, when measuring the angular momentum accuracy is limited, and is impossible to determine as good as they want. Although the phenomenon is related to the measurement process and experimentation, it actually has nothing to do. The experiment not limit the possibility of determining the desired precision values, but rather, is nature itself which limits the accuracy of the experiment . Even with measurement systems ideally perfect.
The Heisenberg uncertainty principle can be understood taking into account what is actually a process of experimental observation. A system is observed through a measurement system. This system, in order to take any steps needed interact with the system of observation, ie, it requires an energy exchange , and that change of power, or status of the meter, is related to some property of the studio system.
However, as the meter has a change of state, the system also observed status change, so to make another type of measurement on the system, it is no longer in the same state, and this second measure is not independent , but depends on the first.
determinism that until that moment was unquestioned, said known initial conditions, it was possible determine with accuracy the evolution of a system. However, Heisenberg demonstrated that it is impossible to know with any precision you want the initial conditions of a system, and therefore can not determine its evolution.
Early in the development of quantum physics to calculate the trajectory of an electron around its nucleus was meaningless because there was no means to observe experimentally. Louis de Broglie casts doubt on the possibility of doing so by stating that the electron is a wave. But Heisenberg completely eliminate this possibility, since it is impossible even imagine an experiment to measure the position and speed of the electron with the necessary precision.
The uncertainty principle is part of nature. But as there is no wave motion of particles in the classical world, the principle is not reflected in these scales. Taking for example an electron and measure its position with an uncertainty of 1 angstrom (the size of an atom), then the uncertainty in the speed will be:
is, if you measured the speed of the electron and was around 5% of the light (so you can ignore relativistic effects), then the uncertainty represents a 46% of measurement. If the speed is much smaller extent, this percentage was much higher. And if given a value far below the uncertainty itself ... is the same as not knowing anything about his speed.
The same indeterminacy of an angstrom in the position of the Earth (mass ~ 10 24 Kg) in its orbit around the Sun, gives an uncertainty in the rate of 6 • 10 -48 m / s. The travel speed of the Earth is 30,000 m / s, so an uncertainty of about 10 -48 m / s is negligible, it represents the order of 10 % -51 of action: it can say that the position and speed of the Earth are perfectly determined.
Werner Heisenberg received the Nobel prize in 1932
Annex
Heisenberg and Gamma rays
was Werner Heisenberg (1901-1976) who came to him, but in a completely different way. Until then, the development of mixed quantum classical physics, with the addition of quantum principles, the result of experimental results. However, a full understanding of nature requires a broader theory, which is deducted from these postulates, we must develop a quantum mechanics.
classical mechanics of Newton's three laws. From these, it is possible to describe any situation, and come to an equation of motion, ie to solve an equation that gives the time evolution of the system studied. This system applies both to describe the oscillation of a spring, as the orbit of a planet around the Sun
Quantum mechanics tries to do exactly the same thing from a common point that is able to describe the evolution of any system at the quantum level. Instead of treating each system owners (photoelectric effect, Compton effect, electron diffraction, the Bohr model for the orbits), it is to get the general behavior of any system based on a certain basis.
The development of these mechanics, Heisenberg came to a rather surprising mathematical result. The development included some mathematical operations that represent the experimental observation of the system. The result was that if you made two comments, for example, the position and angular momentum, the order in which it influences the final result. Mathematically, if an observation A, and one B, this meant that A • B is different from B • A . In fact, its ( A • B - B • A ) is a complex number. This result occurs only for certain amounts related, such as position and momentum, or energy and time.
From the school we are taught that multiplication is commutative. However, this is true when we talk about numbers . When it comes for example, matrices, then this property is not insured. This is how the mechanics of Heisenberg is based on matrix algebra, and hence the development of Heisenberg matrix mechanics call him .
Although mathematically it is possible to understand that A • B is not equal to B • A , what is the point that in the real world? implies that the order in which they performed a measure influences the final result . One can measure the position of a particle with a given accuracy. However, when measuring the angular momentum accuracy is limited, and is impossible to determine as good as they want. Although the phenomenon is related to the measurement process and experimentation, it actually has nothing to do. The experiment not limit the possibility of determining the desired precision values, but rather, is nature itself which limits the accuracy of the experiment . Even with measurement systems ideally perfect.
The Heisenberg uncertainty principle can be understood taking into account what is actually a process of experimental observation. A system is observed through a measurement system. This system, in order to take any steps needed interact with the system of observation, ie, it requires an energy exchange , and that change of power, or status of the meter, is related to some property of the studio system.
However, as the meter has a change of state, the system also observed status change, so to make another type of measurement on the system, it is no longer in the same state, and this second measure is not independent , but depends on the first.
determinism that until that moment was unquestioned, said known initial conditions, it was possible determine with accuracy the evolution of a system. However, Heisenberg demonstrated that it is impossible to know with any precision you want the initial conditions of a system, and therefore can not determine its evolution.
Early in the development of quantum physics to calculate the trajectory of an electron around its nucleus was meaningless because there was no means to observe experimentally. Louis de Broglie casts doubt on the possibility of doing so by stating that the electron is a wave. But Heisenberg completely eliminate this possibility, since it is impossible even imagine an experiment to measure the position and speed of the electron with the necessary precision.
The uncertainty principle is part of nature. But as there is no wave motion of particles in the classical world, the principle is not reflected in these scales. Taking for example an electron and measure its position with an uncertainty of 1 angstrom (the size of an atom), then the uncertainty in the speed will be: 
is, if you measured the speed of the electron and was around 5% of the light (so you can ignore relativistic effects), then the uncertainty represents a 46% of measurement. If the speed is much smaller extent, this percentage was much higher. And if given a value far below the uncertainty itself ... is the same as not knowing anything about his speed.
The same indeterminacy of an angstrom in the position of the Earth (mass ~ 10 24 Kg) in its orbit around the Sun, gives an uncertainty in the rate of 6 • 10 -48 m / s. The travel speed of the Earth is 30,000 m / s, so an uncertainty of about 10 -48 m / s is negligible, it represents the order of 10 % -51 of action: it can say that the position and speed of the Earth are perfectly determined.
Werner Heisenberg received the Nobel prize in 1932
Annex
Heisenberg and Gamma rays
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