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thermodynamics first law sign convention based problem [on hold]

Consider a (frictionless) piston-cylinder system. Initially, one mole of an ideal gas is present in the cylinder. The pressure and temperature of the gas are 1 bar and 300 K. A stirrer slowly ...
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How to find solutions to the gravitational potential metric h

I'm working on a problem in which a star of mass M1, radius R1 is surrounded by a shell of mass M2, , radius R2. I want to find the solutions to the gravitational potential h in the regions in between ...
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What are threshold corrections?

As the title goes, what are threshold corrections in quantum field theory? In particular, I would be glad if a good reference is provided. Standard QFT books such as Peskin, Weinberg, etc seem to ...
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Branch cuts in two-point function

The propagator of a QFT is known to have a branch cut as a function of the (complex) external momentum. The branch point (as done by, say, Peskin & Schroeder in eqn.7.19 section 7.1) is ...
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How come that an Infinite universe will collapse under gravity?

In this PSE post the issue is about the stability of an infinite universe under Newtonian gravity. Here I'will drop the Newtonian constraint because we know of the finite speed of interactions and I ...
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Calculating power [on hold]

I need some help and explanation with solving this question: What is the power required to give a body of mass m a forward acceleration of a when it is moving with velocity v up a frictionless ...
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Is cosmic background radiation absolute [duplicate]

Now that we don't have permeating Ether anymore, why don't we consider the omnipresent Cosmic background radiation in place of it? and measure Speeds with respect to the CMBR? In that way an object ...
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Is work done by sound wave on air particles?

Is it possible for sound wave to do net work on air particles? As in can a sound wave make the air move in one direction so that it can for example move a sail boat ? I think since molecules gyrate ...
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How long would it take to get to Kepler 189f? [on hold]

I just read a news story about a planet that might be Earth-like called Kepler 189f. It is 500 light years away. How long would it take to travel there in a space ship, from the travelers reference ...
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Simulating electrical sublimation of aluminium foil

When i apply high voltage (through a capacitor bank) across an aluminium foil, it gets converted into plasma. I want to simulate this process and study the properties of the plasma produced ...