On the "principle of the quantumness", the quantumness of Relativity, and the computational grand-unification,

I will argue that the proposal of establishing operational foundations of Quantum The- ory should have top-priority, and that the Lucien Hardy’s program on Quantum Gravity should be paralleled by an analogous program on Quantum Field Theory (QFT), which needs to be reformu- lated, notwithstanding its experimental success. In this paper, after reviewing recently suggested operational “principles of the quantumness”, I address the problem on whether Quantum Theory and Special Relativity are unrelated theories, or instead, if the one implies the other. I show how Special Relativity can be indeed derived from causality of Quantum Theory, within the computa- tional paradigm “the universe is a huge quantum computer”, reformulating QFT as a Quantum- Computational Field Theory (QCFT). In QCFT Special Relativity emerges from the fabric of the computational network, which also naturally embeds gauge invariance. In this scheme even the quantization rule and the Planck constant can in principle be derived as emergent from the under- lying causal tapestry of space-time. In this way Quantum Theory remains the only theory operating the huge computer of the universe. Is the computational paradigm only a speculative tautology (theory as simulation of reality), or does it have a scientific value? The answer will come from Occam’s razor, depending on the mathematical simplicity of QCFT. Here I will just start scratching the surface of QCFT, analyzing simple field theories, including Dirac’s. The number of problems and unmotivated recipes that plague QFT strongly motivates us to undertake the QCFT project, since QCFT makes all such problems manifest, and forces a re-foundation of QFT.