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| bio | website | en.wikipedia.org/wiki/… |
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| age | ||
| visits | member for | 1 year |
| seen | 9 mins ago | |
| stats | profile views | 170 |
A Sufi prayer of love
O love, O pure deep love, be here, be now, be all.
Dissolve me into your stainless endless radiance,
Make me your servant, your breath, your core.
:- by sufi mystic Rumi
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9h |
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why can't you use your cellphone on an airplane? Nice question dear! +1 |
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18h |
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Commutator with a square root @dimension10 Is it really that simple? I don't even understand how one would define the square root. |
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Jun 3 |
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Isn't Experience of Nature important for General Theory Of Physics? ..Whether our guess is correct or not can only be decided by some direct or indirect experimental observations. |
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Jun 3 |
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Isn't Experience of Nature important for General Theory Of Physics? "the reason it is so difficult to come up with a general theory of physics is because we do not experience it" : You are right to some extent. In particular if we can not observe some aspect of behaviour of a system there is no way to verify if our understanding of it ( contained in the mathematical model that we have build for it) is correct or not. However, coming up with a mathematical model usually doesn't require experimental observations and is more like guessing the missing part of a zigsaw puzzle when you know what are the other parts. |
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May 31 |
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How does a sponge “suck” up water against gravity? +1 this answer at least explains something and surely doesn't deserve downvotes. |
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May 31 |
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Perfectly focusing refractive surface It would be helpful if you can explain your question with a diagram. |
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May 26 |
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Deriving the Angular Momentum Commutator Relations by using $\epsilon_{ijk}$ Identities Forget about $\epsilon_{ijk}$. Try to derive $[L_1,L_2]=i\hbar L_3$ etc. |
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May 25 |
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What goes wrong when one tries to quantize a scalar field with Fermi statistics? Since you are using anticommutator for quantization so causality would require that the fields anticommute for all spacelike separated points. Since form of the field (as got from time evolution of eta's) will be same as in bosonic case so the fields will fail to anticommute for spacelike separated points. Hence time evolution of eta's is wrong since it is not in accordance with causality. |
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May 24 |
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Is there a general systematic approach how to calculate the individual terms in an operator product expansion? edited body |
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May 24 |
answered | Is there a general systematic approach how to calculate the individual terms in an operator product expansion? |
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May 22 |
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Quantum mechanics and everyday nature Sorry, I read only first line :) |
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May 22 |
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Quantum mechanics and everyday nature I think QM is not really needed to explain their experiment. Wave nature of light too explains it well. In order for two waves to form constructive or destructive interference their polarization should either be random or (anti/)parallel. |
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May 21 |
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How does relativity explain gravity, without assuming gravity "They distort it because they are pulled down by .. what?" :- They are not "pulled down" by anything. Its just that energy interacts with spacetime as per Einstein's equation and makes it curved. |
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May 21 |
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If air contains oxygen and nitrogen, why won't these two elements form water? For chemistry stack exchange it would make a good question I think. Why we don't have oceans filled with N2O instead of water? |
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May 21 |
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If air contains oxygen and nitrogen, why won't these two elements form water? @anna May be what he wants to ask is why not nitrogen and oxygen make water like liquid. |
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May 20 |
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Why is this not a realisable operation on a quantum system? @wemblem Can you please edit your question to make clear what you are trying to ask? In particular what is an "affine map" ? As per your definition a "physical operation" should be an affine map; then why don't you simply check if the map is "affine" or not? (whatever that means) |
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May 20 |
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Criticism of String Theory by other string theorists D. Friedan (who has done quite a lot of work in string theory) has criticized string theory in this paper. |
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May 20 |
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Why is the temperature zero in the ground state? @joshphysics. If (according to your argument) a system at zero temperature is necessarily in its ground state then it means that system is isolated. But for an isolated system we should use the other definition of temperature which is in terms of rate of change of entropy with energy. |
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May 19 |
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Why is the temperature zero in the ground state? @joshphysics Will your argument work for continuous spectrum too? |
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May 12 |
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Some Dirac notation explanations $\dagger$ is transpose + complex conjugate. |
