# Tag Info

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It's not completely clear what you're asking, but I can make one thing clear: quantum mechanics was not developed with the specific aim of correctly describing the precise amounts to which CHSH inequalities can be violated. Quantum mechanics was developed in the 1920s and early 30s. Bell published his first paper on Bell inequalities in 1964. The first ...

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There is a new book called Physics From Symmetry which is written specifically for physicists and includes a long, very illustrative introduction to group theory. I especially liked that here concepts like representation or Lie algebra aren't only defined, but motivated and explained in terms that physicists understand. Plus no concepts are introduced which ...

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Physics from Symmetry is a book that explains all group theoretical concepts needed to understand the foundations of QFT in great detail and is written specifically for physicists. It's not very technical, but it's great if you want to understand quickly what concepts are really important for modern physics and why. For example, it explains why things ...

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Apparent size is not measured as an ordinary size, in meters. It is actually an angle, so it is measured in degrees or radians. See this picture: The left blog is the eye. Look like as the object moves further, the angle becomes smaller. That is what is called perspective. Sometimes people try to compare apparent size and real size, but that makes no ...

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Since most constants aren't calculated theoretically, but rather they are measured experimentally, this question is impossible to work out. (Or, if calculated theoretically, one uses measured constants for the calculation) Unless you reach infinite precision (Which is impossible in more than one aspect), there's no difference in measuring a rational or ...

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My recommendations are: For Mechanics, Mathematical Methods of Classical Mechanics, by Arnold. For Electromagnetism, Modern Electrodynamics, Zangwill. For Quantum Mechanics, Quantum Physics, Le Bellac, or, at an easier level, Introduction to quantum mechanics, Griffiths. For General Relativity, General Relativity, Wald. This should give you a (good) ...

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As a graduate student, I'll give it a shot with some guesses: a) Quantum gravity This is nothing particular of the times we're living on, but since it is a problem that is far from a solution (or even from a complete definition of the problem), I think a lot of people will continue to work on it. b) Quantum information and quantum computing I think this ...

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It's not taking partial derivatives with respect to an observed particle's position, but rather the space of all possible positions of that particle. Think of the potential energy as being defined prior to the particle having an actual path. Really, at heart, these things are defined on a phase space not on ordinary physical space.

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Since, you haven't started Quantum Mechanics, depending on your country, if you country is like mine i.e. Indian Standard, well it will really work well. The reason would be because on your first year, or at least First Semester itself, you'll be taught the old Quantum Mechanics, which is well pretty much still valid for some conditions. So, it won't be a ...

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As Mark Eichenlaub's Answer states, this is a quote from one of Carrol's admired forerunners. You actually hit nearer the mark with your own words: So, in physics void can mean anything but "void". In modern physics there are only quantum fields, a handful of them: the photon field, electron/ positron field, quark field, gluon field and so forth. In ...

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It depends on your definition of 'surface'. Yes, on the hard rocky surface, temperature and extreme acidity makes it very hard for any sort of electronics to last more than a few minutes But floating at 50km of altitude in Venus the temperature is barely tropical (around $30$ ºC), and sulphuric acid makes about 2% of the atmosphere. That's definitely on the ...

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The difference in the time coordinates for the different observers is entirely a geometrical effect, and is described by a geometrical object called the metric tensor. Entropic arguments tend to be used to try and explain the flow of time i.e. the human perception that time flows from past to future. It is important to understand that the flow of time does ...

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A vector is a scalar with direction. So Time can be a vector, but what it means depends on the context. In 1D it has only 2 directions, positive and negative with zero being positive. In 2D it can be an angle between ÷/-Pi radians. And so on. Time can be a single dimension attached to the familiar 3 Euclidian spacial dimensions and in this case it is ...

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