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Both gravity and electrostatic forces depend on distance ($r$) like $1/r^2$. So changing the separation between 2 atoms changes both forces equally. So whichever force is stronger initially (at any distance) will always be stronger. To determine which is stronger consider the ratio of gravitational to electric force. $$ F_g/F_e = 4\pi \epsilon_0 G ...


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The liquid will vaporize. You can just keep sucking. Will not be able to create a vacuum until all the liquid is gone. If you had a barrier between the two and created a vacuum and then removed the barrier you would have vapor of the vapor pressure of the liquid at that temperature.


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A liquid-vapor interface is not a static interface, there is a so-called liquid-vapor equilibrium where molecules in the liquid phase are continuously escaping from the liquid into the vapor phase and vice versa vapor molecules are continuously captured by the liquid. In equilibrium, the number of molecules leaving the liquid into the vapor and leaving the ...


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First let us address "emty space". Empty space is a theoretical concept, a space where there is no matter and no energy. In our universe, no matter how far away one goes in space, it is not empty. It contains the cosmic microwave background radiation, cool photons, which is at a temperature of 2.7 K . Within quantum mechanics and elementary paricles, the ...


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As your QFT theory text should tell you, for an action invariant under G, addition of a Higgs potential only invariant under its subgroup H will spontaneously break the generators in G/H. You ought to do due diligence and study and understand and reproduce all examples of elementary classics such as Ling-Fong Li, PhysRev D9 (1974) 1723. There are, of ...


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For the question, can a soap bubble exist in a vacuum? Your answer places certain assumptions on the soap bubble. Asump 1: There is pressure inside the bubble. Asump 2: There is no gravity. Asump 3: The structure of the bubble has the strength to exert force against the pressure inside the bubble. 1 A total vacuum exerts the same pressure inside the ...


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Expansion A gas is a collection of atoms or molecules that are constantly moving and colliding with each other. Credit for this great visualization goes to Greg L at the English language Wikipedia. If the bounding box were to disappear, the particles would escape in the direction they were previously travelling - which for lots and lots of particles ...


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In 1997 the Hubble discovered a large numbers of intergalactic stars. Others have since been discovered. It is now believed that about 1/2 of the stars in the universe may well be rogue stars that are located in intergalactic space. The AVERAGE density of intergalactic space is still very small, however, because of its immense size.


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normal ordering is a valid operation provided one can undo it by an appropriate choice of counterterms (of existing couplings or field renormalisations). (How this is done in practice is explained here: http://arxiv.org/abs/1512.02604.)



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