Is this because our measurement of one variable, say the position x, causes a change in momentum px, i.e. the sister variable's value. The answer to this question is that this principle makes no statement of cause and effect! It just states that one cannot measure values for these sister variables with unlimited accuracies. Further more, these uncertainties are related as quoted in the above "equation". To state that x measurement causes or interferes with the momentum measurement is an inference beyond the statement of the Heisenberg Uncertainty Principle. It is, however, fair to ask why is there such a connection. Said differently, why is there the Heisenberg Uncertainty Principle? But we've already answered this question, albeit with a troubling outcome! It is a consequence of the wave description in quantum theory. Because all of our measurements to date agree with this description, we could then state that this uncertainty principle is simply the consequence of the way nature behaves. If we wish, then we could go a step further and infer that perhaps there is no independent (self existing) reality in the values of our interconnect measurables!
The theories behind Quantum Mechanics (QM) cannot come from Vedas. Heisenberg himself said if Uncertainty Principle (UP) is wrong then QM will become wrong also. If you look at the proof of UP from the one given by Heisenberg himself you will find it is completely wrong. It begins with an absurd assumption that can never happen in nature. It appears that 99% of the QM people did not read the original proof of Heisenberg’s UP or they want to avoid facing the real truth of UP.
I have heard various definitions of the uncertainty principle
Heisenberg's uncertainty principle is a direct consequence of this wave formulation and the fact that waves seem to connect separately measurable domains together! In its most commonly quoted form, Heisenberg's uncertainty principle connects the "position domain" with the "momentum domain". But there are other "sister" domains that are also interconnected; such as time and energy. In particular, Heisenberg's Uncertainty Principle states that the product of the uncertainty in one variable with the uncertainty in the other variable has a fixed lower limit. In terms of an equation, it states: (p)(q) cannot be smaller than h, where p is the uncertainty is the measurable p and q is the uncertainty in the measurable q, and h is some fixed (universal) constant (named after Planck; in SI system of units its value is 6.63x10-34). What does this mean?