# Why is the Heisenberg Uncertainty Principle not obvious give the conservation of mass- energy?

A photons energy is given by $E=h *f$ and momentum $p=E/c$ (spin?) but the photon has no (rest) mass! Therefore it is the ultimate probing tool for looking at any mass position and velocity because mass transfer is not involved only momentum.But to calculate/ measure the particles exact position by scattering a photon from the mass into a detector dictates some of the photons momentum has been transferred to the mass i.e. the mass has to move (is disturbed from it initial position by some delta). This is intuitively obvious ;I would like to see how Heisenberg quantified(proved) this uncertainty hopefully without referring to an ansatz wave function.

• The "uncertainty" you're describing is not the same uncertainty that appears in Heisenberg's principle. Maybe that's the answer you're looking for, and if so I'll post it as such, but before it comes to that I would suggest reading some of the related questions linked at the right, such as this one, and seeing whether they can help you clarify your question. Commented May 19, 2013 at 7:06