[ad_1]
A new principle of uncertainty is that quantum objects can be at two temperatures at once, which is similar to the famous Schrödinger thought experiment, in which a cat in a box with a radioactive element can be alive or death.
Credit: Shutterstock
The famous thought experiment known as the Schrödinger cat implies that a cat in a box can be both dead and alive – a weird phenomenon that is the consequence of quantum mechanics.
Now, physicists from the University of Exeter in England have discovered that there may be a similar state of uncertainty for temperatures: objects can be at two temperatures simultaneously at the same level. quantum. This strange quantum paradox is the first completely new quantum uncertainty relationship to be formulated for decades.
The other principle of Heisenberg
In 1927, the German physicist Werner Heisenberg postulated that the more precisely the position of a quantum particle is measured, the less one can know its momentum and vice versa – a rule that will become the principle of uncertainty of Heisenberg. [Twisted Physics: 7 Mind-Blowing Findings]
The new quantum uncertainty, which states that the more precisely you know the temperature, the less energy you can say, and vice versa, has big implications for nanoscience, which studies incredibly small and sub-nanometer objects. This principle will change the way scientists measure the temperature of extremely small things such as quantum dots, small semiconductors or individual cells, the researchers said in a new study published in June in the journal Nature Communications.
In the 1930s, Heisenberg and Danish physicist Niels Bohr established an uncertainty relationship between energy and temperature on the non quantum scale. The idea was that if you wanted to know the exact temperature of an object, the most accurate and precise scientific means would be to immerse it in a "reservoir", for example a water tank or a refrigerator filled cold air – with a known temperature, and allow the object to slowly become this temperature. This is called thermal equilibrium.
However, this thermal equilibrium is maintained by the object and the reservoir in constant energy exchange. The energy of your object goes up and down in infinitesimal amounts, making precise definition impossible. On the other hand, if you wanted to know the precise energy of your object, you will have to isolate it so that it can not come in contact with, and exchange energy. with anything. But if you isolate it, you would not be able to accurately measure its temperature using a tank. This limitation makes the temperature uncertain.
Things get more bizarre when you go to the quantum scale.
A new relationship of uncertainty
Even if a typical thermometer has an energy that goes up and down slightly, this energy can still be known in a small range. This is not at all the case on the quantum plan, showed the new study, and all this is due to the Schrödinger cat. This thought experiment proposed a theoretical cat in a box with a poison that could be activated by the disintegration of a radioactive particle. According to the laws of quantum mechanics, the particle could have disintegrated and not disintegrated at the same time, which means that the cat would be both dead and alive, a phenomenon known as superposition.
Researchers used mathematics and theory to predict exactly how this superposition affects the measurement of the temperature of quantum objects. [Wacky Physics: The Coolest Little Particles in Nature]
"In the quantum case, a quantum thermometer … will be in a superposition of states of energy simultaneously," Harry Miller, one of the physicists at the University of Exeter, told Live Science. principle. "What we find is that the thermometer no longer has a well-defined energy and that it is actually in combination with different states, which contributes to the uncertainty of the temperature that we can measure. "
In our world, a thermometer can tell us that an object is between 31 and 32 degrees Fahrenheit (minus 0.5 and zero degrees Celsius). In the quantum world, a thermometer can tell us that an object is both these temperatures at the same time. The new principle of uncertainty explains this quantum strangeness.
Interactions between objects at the quantum scale can create overlays and create energy. The old uncertainty relationship ignored these effects because it does not matter for non-quantum objects. But it matters a lot when you are trying to measure the temperature of a quantum dot, and this new relationship of uncertainty provides a theoretical framework for taking these interactions into account.
The new document could help anyone design an experiment to measure temperature changes in objects below the nanometer, Miller said. "Our result will tell them exactly how to accurately design their probes and tell them how to take into account the extra quantum uncertainty you're getting."
Originally published on Live Science.
[ad_2]
Source link
