2017成都建博会宣传强势来袭 企业参展热情高涨
48,852 questions with no upvoted or accepted answers
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Intuition for Homological Mirror Symmetry
first of all, I need to confess my ignorance concerning physics since I'm a mathematician. I'm interested in the physical intuition of the Langlands program, therefore I need to understand what ...
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Is there an equivalent of Rindler coordinates for an object in centripetal motion?
Rindler coordinates are a parametrization of (a subset of) Minkowski space that are "natural" for an object experiencing constant acceleration - more specifically, an object experiencing ...
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LSZ reduction theorem derivation in Weinberg QFT
When deriving LSZ reduction theorem Weinberg in his QFT book have assumed n-point generalized Green functions,
$$
G(q_{1},...,q_{n}) = \int d^{4}x_{1}...d^{4}x_{n}e^{-i\prod_{i =1}^{n}q_{j}x_{j}} \...
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Significance for LQG of Sen's result on entropy of black holes?
Sen 2013 says,
...we apply Euclidean gravity to compute logarithmic corrections to the entropy of various non-extremal black holes in different dimensions [...] For Schwarzschild black holes in four ...
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Transforming a sum into an integral
I posted this in the mathematical forums. Maybe you will help me. I found an hard article Link of yang huang and luttinger. The authors begins with the sum: $$\frac{{E_2 }}{{E_0 }} = \frac{{16\pi ^2 a^...
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What's the cause of this gap in this simulation of the Nice model?
A previous question brought me to this video (which has a spectacular change at about 0:34). It shows the orbits of Jupiter, Saturn, Uranus, Neptune, and what appear to be trans-Neptunian objects.
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What's the densest known material that has been made in macroscopic quantities?
I'm aware that the densest stable element is osmium at 22.61?g/cm3.
And that there are unstable elements such as hassium and meitnerium which are predicted to have densities of 41?g/cm3 and 37.4?g/cm3 ...
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Nuclear spectral theorem in Rigged Hilbert Spaces (Gelfand-Maurin theorem)
Before I go into the question, I would like to mention that I am a physicist with some formal mathematical knowledge, but not expert in functional analysis.
In physics, we very often say: Let $|x \...
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Pressure underneath wave
I enjoy water sports and activities in the water. I've swam around and dived down enough to need to equalize my ears and in general have felt water pressure.
I've since taken up surfing and have ...
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Can you put the Spin Connection in block diagonal form? (to be applied to the Atiyah-Singer theorem)
I'm following the notes by Freed about the Dirac Operator. In section 5.4, equation (5.4.25-27), he makes the following claim about the Dirac operator. In a different notation than what he is using, ...
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Entropy and equilibrium concepts at astronomic scales
I am always puzzled to read here and there discussions dealing with thermodynamic concepts applied to astronomic scales where gravity matters. To my opinion, there is a certain carelessness to go into ...
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Can we do a Wick rotation by an angle not being $\pi/2$?
If a state obeys an evolution equation, we can replace $t$ by $-t$. we get another equation and it is interesting to study its solutions.
If we replace $t$ by $it$ (wick rotation) we get again ...
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Can cut-off regularisation cause a Poincaré anomaly?
Momentum cut-off regularisation leads to non-covariant results, i.e., it breaks the Poincaré covariance of the theory. Is there any guarantee that Poincaré covariance is always restored when we remove ...
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2-nd quantized TQFT formalism?
Suppose that we have a certain TQFT in the Atiyah-Singer sense. It is given by a functor $Z$ which associates:
To connected oriented $n-1$-manifolds $a, b, \dots$ (in what follows called compact ...
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Topological quantum error correcting codes which are not CSS codes
The most promising-seeming quantum error correction codes for the medium-to-long term are the topological codes, of which the toric code (and variants such as planar surface codes) and colour codes ...
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