1、 Neutrinos and the hypothetical gravitons, also massless particles, move at the same speed as light.
中微子和假想的引力子也是无质量粒子, 它们也以与光相同的速度运动.
来源:——辞典例句
2、 An all - pervading , infinitely elastic, massless medium formerly postulated as the medium of propagation of electromagnetic waves.
以太,能媒一种在以前被假定为电磁波的传播媒质并具有''.'绝对'.''连续性 、 ''.'高度'. ''弹性的极其稀薄的媒体.
来源:互联网
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