Quantum weirdness: two temperatures in one body! (Introduction)

by David Turell , Tuesday, September 18, 2018, 17:36 (2048 days ago) @ David Turell

A cat can be alive and dead and a new study finds two different temperatures in one item:

https://www.livescience.com/63595-schrodinger-uncertainty-relation-temperature.html?utm...

"In 1927, German physicist Werner Heisenberg postulated that the more precisely you measure a quantum particle's position, the less precisely you can know its momentum, and vice versa — a rule that would become the now-famous Heisenberg uncertainty principle.

"A new uncertainty principle holds that quantum objects can be at two temperatures at once, which is similar to the famous Schrödinger's cat thought experiment, in which a cat in a box with a radioactive element can be both alive and dead.

"The famous thought experiment known as Schrödinger's cat implies that a cat in a box can be both dead and alive at the same time — a bizarre phenomenon that is a consequence of quantum mechanics.

"Now, physicists at the University of Exeter in England have found that a similar state of limbo may exist for temperatures: Objects can be two temperatures at the same time at the quantum level. This weird quantum paradox is the first completely new quantum uncertainty relation to be formulated in decades.

"The new quantum uncertainty, which states that the more precisely you know temperature, the less you can say about energy, and vice versa, has big implications for nanoscience, which studies incredibly tiny objects smaller than a nanometer. This principle will change how scientists measure the temperature of extremely small things such as quantum dots, small semiconductors or single cells, the researchers said in the new study.

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"The researchers used math and theory to predict exactly how such superposition affects the measurement of the temperature of quantum objects.

"'In the quantum case, a quantum thermometer ... will be in a superposition of energy states simultaneously,"Harry Miller, one of the physicists at the University of Exeter who developed the new principle, told Live Science. "What we find is that because the thermometer no longer has a well-defined energy and is actually in a combination of different states at once, that this actually contributes to the uncertainty in the temperature that we can measure."

"In our world, a thermometer may tell us an object is between 31 and 32 degrees Fahrenheit (minus 0.5 and zero degrees Celsius). In the quantum world, a thermometer may tell us an object is both those temperatures at the same time. The new uncertainty principle accounts for that quantum weirdness.

"Interactions between objects at the quantum scale can create superpositions, and also create energy. The old uncertainty relation ignored these effects, because it doesn't matter for nonquantum objects. But it matters a lot when you're trying to measure the temperature of a quantum dot, and this new uncertainty relation makes up a theoretical framework to take these interactions into account."

Comment: Another addition to quantum wackiness, which is the basis of our reality.