We give an efficient decision procedure that, on input two (acyclic) cryptographic expressions making arbitrary use of an encryption scheme and a (length doubling) pseudorandom generator, determines (in polynomial time) if the two expressions produce computationally indistinguishable distributions for any pseudorandom generator and encryption scheme satisfying the standard security notions of p...

An increasingly important design constraint for software running on ubiquitous computing devices is security, particularly against physical methods such as side-channel attack. One well studied methodology for defending against such attacks is the concept of indistinguishable functions which leak no information about program control flow since all execution paths are computationally identical. ...

An accurate forecast of a nonlinear system will require an accurate estimation of the initial state. It is shown that even under the ideal conditions of a perfect model and infinite past observations of a deterministic nonlinear system, uncertainty in the observations makes exact state estimation is impossible. Consistent with the noisy observations there is a set of states indistinguishable fr...

We discuss quantum correlations in systems of indistinguishable particles in relation to entanglement in composite quantum systems consisting of well separated subsystems. Our studies are motivated by recent experiments and theoretical investigations on quantum dots and neutral atoms in microtraps as tools for quantum information processing. We present analogies between distinguishable particle...

Intelligent agents perceive the world mainly through images captured at different time points. Being able to track objects from one image to another is fundamental for understanding the changes of the world. Tracking becomes challenging when there are multiple perceptually indistinguishable objects (PIOs), i.e., objects that have the same appearance and cannot be visually distinguished. Then it...