 4:43 AM
1  I was thinking about some physics (relativity in particular), when it suddenly occurred to me that all my life I had been balancing chemical equations assuming conservation of mass, but I was disregarding energy! For example, consider combustion: $$CH_4 + 2O_2 >>> 2H_2O + CO_2 + {Energy}$$ Howe...

7 hours later… 11:44 AM
1  When we go from the classical many-body hamiltonian H = \sum_i \frac{\vec{p}_i^2}{2m_e} - \sum_{i,I} \frac{Z_I e^2 }{|\vec{r}_i - \vec{R}_I|} + \frac{1}{2}\sum_{i,j} \frac{ e^2 }{|\vec{r}_i - \vec{r}_j|} + \sum_I \frac{\vec{p}_I^2}{2M_I}+ \frac{1}{2}\sum_{I,J} \frac{Z_IZ_J e^2 }{|\vec{R}_I - \... 12:23 PM
2  Is it possible for an electric field exist,that its electric field intensity continuously increases(like E=kx),while all the E-vectors pointing the same direction(I mean,parallel vectors)?

10 hours later… 10:20 PM
2  One student of mine has found one question in a book of thermodynamics (1st year university level). Work or Heat? You grab a bottle of juice and shake it thoroughly. Is this an example of a work or a heat interaction? Recall that work can be described with mechanical or electromagnetic va...