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its_about_time_._note [2016/01/05 16:59] nikolaj |
its_about_time_._note [2016/02/16 14:01] nikolaj |
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| $h_\Psi\cdot\dfrac{{\mathrm d}}{{\mathrm d}t}\Psi = (-2\pi{\mathrm i})\,H\,\Psi$ | $h_\Psi\cdot\dfrac{{\mathrm d}}{{\mathrm d}t}\Psi = (-2\pi{\mathrm i})\,H\,\Psi$ | ||
| - | and note that if $h_\Psi$ is chosen unitless, the conserved quantity of the system (what is also called energy) is a frequency. | + | and note that if $h_\Psi$ is chosen unitless, the conserved quantity of the system (what is also called energy) is a frequency. |
| - | The cost associated with a process inversely proportional to how quick it takes place. | + | The cost associated with a process is basically inversely proportional to how quick it takes place, so that Reaching higher frequencies is more expensive. But for a more precise desciption in QM, one must look at the state spaces in the models. |
| - | E.g. reaching higher frequencies is "more expensive". | + | |
| - | To understand many formulas, units like e.g. mass ($kg=s/m^2$, after setting $\hbar$ unitless) can or should be multiplied by natural constants (e.g. $c^2$) so that they represent a frequency or time scale. | + | |
| A Hamiltonian $H(\langle q,p\rangle)$ is like an $\langle q,p\rangle$-indexed list of prices. A Hamiltonian operator $H$ acting on state vectors in QM is like a stamp with prices. | A Hamiltonian $H(\langle q,p\rangle)$ is like an $\langle q,p\rangle$-indexed list of prices. A Hamiltonian operator $H$ acting on state vectors in QM is like a stamp with prices. | ||
| + | |||
| + | To understand many formulas, units like e.g. mass ($kg=s/m^2$, after setting $\hbar$ unitless) can or should be multiplied by natural constants (e.g. $c^2$) so that they represent a frequency or time scale. | ||
| == Canonical variables == | == Canonical variables == | ||
| Line 35: | Line 34: | ||
| $[q,p] \propto \hbar$. | $[q,p] \propto \hbar$. | ||
| + | |||
| + | == List of quantities that multiply to frequency/energy == | ||
| + | (this is a temporary list for me to read formulas in terms of units) | ||
| + | |||
| + | Electrical field $[E]=\dfrac{1}{[t][x][q_x]}$ and dipole moments $[d]=[x][q_x]$. | ||
| ----- | ----- | ||
| === Related === | === Related === | ||
| - | [[Perspective]] | + | [[On physical units . note]], [[Perspective]] |
