中文摘要：

动量守恒和角动量守恒长期以来被认为是物理学基本守恒定律。在此给出一个不符合这两个定律的实际例子，表明动量和角动量都不是绝对的守恒量。我们发现在一定的条件下，两个相互接触的物体之间的作用力和反作用力引起其中一个物体的动量变化和另一个物体的角动量变化，这意味着系统的总动量在无外力的情况下发生变化，同时系统的总角动量在无外力矩的情况下也发生改变。我们还发现如果系统的动量和角动量不守恒，这两种不守恒必须同时发生，因此我们预言系统的某个未知的和更一般的守恒量在此情况下仍然是守恒的。我们预计这个研究将是从一个新的视角重新审视经典物理学的起点。另外，我们预计我们的试验对于为空间飞行器一类的孤立系统的推进寻找火箭反冲方式以外的新方法也是一个起点。

英文摘要：

Conservation of momentum and angular momentum have long been regarded as the two basic laws in physics. However, an example that does not conform to the two laws is given ; that shows that none of momentum and angular momentum is an absolute conserved quantity. We found that under certain conditions, the action-reaction pair acting between two bodies touching each other changes the momentum of one body and the angular momentum of the other one. That means that the total momentum of the system is changed without any external force, and the total angular momentum of the system is also changed without any external moment. Furthermore, we found that if the momentum and the angular momentum of a system are not conserved, the two kinds of non-conservation must occur at the same time ; therefore, we predict that an unknown and more general conserved quantity of the system is still conserved in this case. We anticipate our study to be a starting point for reexamining the classical physics from a new viewpoint. Additionally, we anticipate our assay to also be a starting point for searching a new propulsion mode besides rocket recoil mode for an isolated system such as spacecraft.