That's not a positive and negative charge, that's actually a phase, and that arises from the wave equation.

这不是指正负电荷，它是指相位，这是从波函数中得来的。

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The purely electric drive system was factored into the equation as early as the concept phase when the gullwing model was being developed.

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There are fears, however, that the Prince deal marks a new phase in which established artists will cut record companies and traditional retailers out of the equation.

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