Tagged: Quantum Mechanics

Philosophical Implications of Quantum Mechanics

Richard Feynman (1918-1988) argues in his famous Lectures on Physics (1961/62) that finite accuracy of measurement also makes the future very unpredictable, because even very small errors in prediction have cascading effects that lead to vastly different outcomes. Thus, the difference between a classical interpretation (deterministic) and a quantum-mechanical explanation (indeterminisitc) is not as categorical as we sometimes assume. He compares classical and quantum-mechanical approaches to physics, and comes to the conclusion that “…it  is not true that we can pursue science completely by using only those concepts which are directly subject to experiment.” If this applies to physics, it is...

Schrödinger’s Cat

In 1935 Schrodinger published an essay describing the conceptual problems in Quantum mechanics. A brief paragraph in this essay described the cat paradox: “One can even set up quite ridiculous cases. A cat is penned up in a steel chamber, along with the following diabolical device (which must be secured against direct interference by the cat): in a Geiger counter there is a tiny bit of radioactive substance, so small that perhaps in the course of one hour one of the atoms decays, but also, with equal probability, perhaps none; if it happens, the counter tube discharges and through a...

Quantum Nonlocality

Quantum nonlocality is a paradox that was described first by Einstein, Podolsky, and Rosen (EPR), who published the idea in 1935. The EPR paradox draws attention to a phenomenon predicted by quantum mechanics known as quantum entanglement, in which measurements on spatially separated quantum systems can instantaneously influence one another. As a result, quantum mechanics violates a principle formulated by Einstein, known as the principle of locality or local realism, which states that changes performed on one physical system should have no immediate effect on another spatially separated system. Our “local realistic” view of the world assumes that phenomena are...

Vacuum Fluctuations

How the Universe can come from Nothing: The following quotes address vacuum fluctuations and the idea that things – perhaps even the entire universe – can indeed arise from nothing via natural processes. Vacuum Fluctuations and Virtual Particles In the everyday world, energy is always unalterably fixed; the law of energy conservation is a cornerstone of classical physics. But in the quantum microworld, energy can appear and disappear out of nowhere in a spontaneous and unpredictable fashion. (Davies, 1983, 162) The uncertainty principle implies that particles can come into existence for short periods of time even when there is not...

What is Quantum Mechanics?

Quantum mechanics is a branch of physics; it was developed between 1900 and 1930, and  it explains the behavior of sub-atomic particles, atoms, molecules and nuclei. Attempts to combine it with the general and special theory of relativity leads to new and revolutionary types of theories. Experimental evidence forced the creation of new concepts, like the particle properties of radiation, the wave properties of matter, the quantization of physical properties, or  the idea that one can no longer know exactly where a single particle such as an electron is at any one moment. Some of the basic insights of quantum...