EP1. 乘法与加法的思维方式nEP2.微积分nEP3.庞加莱猜想——For a topologist,all these shapes-sorry-these manifolds can be created from each other by deformation; therefore they are identical,or rather"homeomorphic",as they say in these parts.So a ball and a cube are homeomorphic manifolds,as are a vase and a plate,which are basically just balls which have been deformed!This is why topologists sometimes put flowers in completely flat vases,which is difficult for the flowers which know nothing about topology.
EP1. 乘法与加法的思维方式nEP2.微积分nEP3.庞加莱猜想——For a topologist,all these shapes-sorry-these manifolds can be created from each other by deformation; therefore they are identical,or rather"homeomorphic",as they say in these parts.So a ball and a cube are homeomorphic manifolds,as are a vase and a plate,which are basically just balls which have been deformed!This is why topologists sometimes put flowers in completely flat vases,which is difficult for the flowers which know nothing about topology.