# Tag Info

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The vapor pressure of your water column at 50 degrees C is approximately 100 Torr, which is 1/7.6 of one atmosphere. The pressure in the water column is given by the equation $P = \rho g h$ , where $\rho$ is the density of the water, g is the local acceleration due to gravity, and h is the height of the water column above a stated point. The water will ...

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We say that sound waves need a medium to propagate and we know that light doesn't need such a thing. But is that really how that works? There's no such thing as "nothing" according to Quantum Mechanics, so I'm wondering if light can travel through "perfect vacuum"? Right, but light is not a quantum mechanical concept. It is a well fitted macroscopic ...

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Secrets of the Universe In the beginning was infinite geometric space. This space became filled with Static Time at absolute rest and absolute cold. Static time is strictly quantitative, and does not differentiate between past, present and future. Being quantifiable and measurable, static time is a scientific concept. Static time of 0.0033 microseconds per ...

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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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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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The universe is not EMPTY. It is governed by dark matter (80%)!.The universe is also filled with neutrino. THE universe wouldn't then be expanding because new matter particles is being created(however they again disappear). Think it like a balloon being blown, as more particle goes in, the balloon expands. In other words, expansion is directly proportional ...

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Such phenomena as Casimir effect (especially dynamic version of the effect) and Lamb shift are typical manifestations of the quantum fluctuations. An existence of quantum fluctuations is really intuitive fact if you use an uncertainty principle, which tells us that particles can pop out of the vacuum during a very short time interval.

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The use of a Tesla high vacuum pump is indeed very compelling. I did some research during university for its use as a fluid pump, quite similar to the 2008 one you cited. I guess the design approach might be that of the many particles. At ambient temperature, the average speed of air molecules is about 500 m/s, which is comparable to the tip speed of a high ...

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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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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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The state of a substance depends very much on its temperature. There can be a change of state due to expansion that is how gas liquefiers work. A gas is compressed and then is allowed to expands rapidly. In expanding the gas does work against the surroundings and in separating the gas molecules so the average kinetic energy of its molecules drops ie it ...

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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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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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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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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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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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