Question

Is it possible for several scientists who have never met each other to contribute to the same scientific knowledge, theory, or law? explain please

Answer 1

Yes, the atomic theory is a good example, it started from a Greek dude and hundreds of years later, more stuff got added by different dudes

Answer 2

Yes they can contribute to same scientific knowledge because as you know scientific concepts are same through out the world.
As concept of battery was given by Alessdro Volta but now the same concept is used to create batteries in world as well as if you will consider the electromagnetic waves phenomenon which also same because we receive signals from space and the phenomenon is same through out the world.