We show that D = 4 Minkowski space can be found to be associated with a certain type of operators in extended Hilbert space. We start with the concept of external operators introduced in [1] to make the connection between quantum entanglement and geometry predicted by ER=EPR conjecture more transparent. We discuss eigenequations of the simplest operators and identify D = 4 Minkowski space as spanned by normalized eigenvectors corresponding to the zero eigenvalue. Both spacetime dimension and signature of the metric will be fixed by the regularization procedure determining normalized eigenvectors. We generalize the result to the case of more complex operators, being direct equivalents of quantum fields. We reproduce the Minkowski space again, identifying it with the conformal boundary of AdS 5 . The latter emerges as a special solution in a class of higher-dimensional spaces. We observe an interesting analogy to string theory and, in particular, AdS/CFT correspondence. a