There are mainly two hypotheses on it, one is the M hypothesis which assumes that the force lines co-rotate with the magnet, and the other is the N hypothesis which as.
两种主要观点是：M理论认为磁场随着磁体一起转动；N理论认为磁场不随磁体一起转动。
The threshold and accumulation effects of N deposition could also be predicted by an intermediate disturbance hypothesis(IDH).
沉降的阈值效应和累积效应也都符合中度干扰理论。
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