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Name: Thomas
Status: student
Grade: other
Country: Netherlands
Date: Summer, 2011


Question:
Under Heisenberg's uncertainty principle, events may occur (such as the existence of virtual particles) that need not obey the conservation of energy, however, as the universe as a whole can be considered to be a closed system, does it then not hold true that even if emerging from the "vacuum" for a very brief moment, the rule of conservation over the total (the universe as a whole) remains unbroken?

Replies:
Thomas,

Very short events that do not obey energy conservation happen at the level of individual particles quite often. It is important to understand that the energy boosts happen for very short times, often too short to measure. The energy before the event balances with the energy after the event. It is getting from start to finish that requires the temporary boost.

Dr. Ken Mellendorf Physics Instructor Illinois Central College


The short answer is "No". However, to answer the question "Why?" requires some rooting around in the interpretation of the mathematics of quantum mechanics. I searched the term "Heisenberg Uncertainty Principle and the Conservation of Energy". The explanations I found require an examination of exactly what do you mean by "energy" and what do you mean by "time". The definitions are not the usual classical definitions. I do not know your level of mathematical skills, so it is not proper to just "throw out" some abstract explanation. If you search the search term above you will find a lot of discussion around the topic.

Vince Calder





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