ABV Posted February 18, 2016 Share Posted February 18, 2016 The magnetic field could distort entropy of substance and change its temperature.Based on this, possible build a kind of virtual demon of Maxwell, which is based on the distortion of entropy of the substance.This distortion of entropy also allow to have virtual locations with different temperature. In case with magnetocaloric effect the different temperature virtual locations is exists when observed object is present in this location. Will this machine work? This example shows machine which utilize the magnetocaloric effect This example contains a electromagnet, a paramagnetic element which connected with piston and cylinder with gas. All system is experiencing a gravity force. At initial time, based on magnetocaloric effect the electromagnet will increase temperature of paramagnetic from T1 to T2. The paramagnetic element will heat a gas which will increase its internal energy. This increase of internal energy will make a gas expansion into cylinder and the piston will remove paramagnetic element from magnetic field of the electromagnet. The temperature of the paramagnetic element will be decreased and it will start cool down the gas from temperature T2 to T1. This will reduce the gas internal energy and it will reduce a pressure of gas inside the cylinder. The piston will move into initial position and it will return the paramagnetic element into magnetic field of the electromagnet again. Link to comment Share on other sites More sharing options...
swansont Posted February 18, 2016 Share Posted February 18, 2016 The magnetic field could distort entropy of substance What does this mean? Entropy is a scalar value. How can one distort it? Link to comment Share on other sites More sharing options...
ABV Posted February 19, 2016 Author Share Posted February 19, 2016 What does this mean? Entropy is a scalar value. How can one distort it? Looks like "distortion of entropy" confuses everybody. Based on second thermodynamic law the entropy should stay same or goes higher for isolated systems. So, when magnetic field polarize magnetic spins, then the entropy cannot be decreased for isolated systems. However, the entropy "changes its own shape" and temperature goes higher for substance with polarized magnetic spins. So, this I call it as distortion of entropy. Link to comment Share on other sites More sharing options...
swansont Posted February 19, 2016 Share Posted February 19, 2016 Looks like "distortion of entropy" confuses everybody. Based on second thermodynamic law the entropy should stay same or goes higher for isolated systems. So, when magnetic field polarize magnetic spins, then the entropy cannot be decreased for isolated systems. However, the entropy "changes its own shape" and temperature goes higher for substance with polarized magnetic spins. So, this I call it as distortion of entropy. the entropy "changes its own shape" doesn't really help. Maybe if you refrained from introducing nonstandard terminology? Entropy goes up, goes down, or stays the same. If you add an external magnetic field to polarize the spins, you do not have an isolated system. Decreasing the entropy of the spins is precisely what happens — this is how magnetic refrigeration works. 1 Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted February 20, 2016 Share Posted February 20, 2016 With regard to whether the machine could work. You also need a changing magnetic field. So even if you expand your isolated system to include the magnetic field, you need a further external source of energy to drive it. Link to comment Share on other sites More sharing options...
ABV Posted February 20, 2016 Author Share Posted February 20, 2016 the entropy "changes its own shape" doesn't really help. Maybe if you refrained from introducing nonstandard terminology? Entropy goes up, goes down, or stays the same. If you add an external magnetic field to polarize the spins, you do not have an isolated system. Decreasing the entropy of the spins is precisely what happens — this is how magnetic refrigeration works. May be you right. However, polarizing of magnetic spins and decreasing an entropy inside substance won't allow to happen magnetocaloric effect. In this case the temperature will remain the same. Link to comment Share on other sites More sharing options...
swansont Posted February 20, 2016 Share Posted February 20, 2016 May be you right. However, polarizing of magnetic spins and decreasing an entropy inside substance won't allow to happen magnetocaloric effect. In this case the temperature will remain the same. This is how magnetic refrigeration works, so no. When you polarize the spins, the temperature goes up https://en.m.wikipedia.org/wiki/Magnetic_refrigeration Link to comment Share on other sites More sharing options...
ABV Posted February 24, 2016 Author Share Posted February 24, 2016 This is how magnetic refrigeration works, so no. When you polarize the spins, the temperature goes up https://en.m.wikipedia.org/wiki/Magnetic_refrigeration During magnetic spin polarization, the substance are losing one of the vibrational degree of freedom. This changes a heat capacity of substance and temperature goes up. When paramagnetic element away from magnetic field then substance are getting this vibration degree of freedom back and temperature does down. It seems like law of momentum conservation what is working on nuclear level. I'm sorry about confusion with terminology "distortion of entropy". It's unofficial name of this process. However, I like it better. Link to comment Share on other sites More sharing options...
Mordred Posted February 24, 2016 Share Posted February 24, 2016 The same degrees of freedom still exist. What your describing is the changes within the electromagnetic degrees of freedom. Not the number of degrees of freedom. Link to comment Share on other sites More sharing options...
ABV Posted February 25, 2016 Author Share Posted February 25, 2016 The same degrees of freedom still exist. What your describing is the changes within the electromagnetic degrees of freedom. Not the number of degrees of freedom. Sure, the degree of freedom still exist. However, the magnetic field will reduce fluctuations on this degree of freedom. Therefore, this reduction of fluctuation on this degree of freedom will reduce the heat capacity of substance. Link to comment Share on other sites More sharing options...
Mordred Posted February 25, 2016 Share Posted February 25, 2016 That statement is more accurate. Thanks Link to comment Share on other sites More sharing options...
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