What has become of reality in modern physics?

Grace Marmor Spruch, Henry Margenau

Patrick A. Heelan

Chuanjie Dai

Roger Penrose’s The Road to Reality is one of the most ambitious modern attempts to describe how mathematical structures lead toward physical reality. Its route passes through complex numbers, geometry, spinors, field theory, quantum mechanics, relativity, twistor theory, and the unresolved tension between quantum theory and gravity. This paper gives an independent reading of Penrose’s project from the standpoint of the PAC–µ 8 framework. The central thesis is that Penrose’s road may be understood as a passage from mathematical structure to physical reality, whereas PAC–µ 8 refines that passage into a finite-window certification chain: Process −→ Generator −→ Spectrum −→ Boundary −→ Record −→ Certificate −→ Reality. On this reading, mathematical structure is not rejected; it is treated as the indispensable candidate skeleton of reality. However, PAC–µ 8 adds a missing mediating layer: boundary formation, record production, and certification below a threshold. Complex numbers become minimal phase-certification structures; spinors and twistors become orientation and causal phase encoding structures; geometry becomes the compressed cost of record comparison; measurement becomes boundary-induced certification; and physical objects become persistent certified packets rather than primitive substances. The paper concludes that Penrose’s mathematical realism can be absorbed and strengthened as a form of certification realism: mathematics opens the road to reality, but only certified mathematical structure enters physical reality.

Amrit Šorli, Steve Kaufman

In physics today it often happens that experimental data is interpreted as proof of a phenomenon that has not been directly observed, but for which phenomenon there is a theoretical model. With the obtained data acting thereby as proof, the model then becomes recognized as “real,” after which the theoretical phenomenon that the model describes also then becomes recognized as “real” – that is, the heretofore purely theoretical phenomenon is acknowledged as a physical reality, even though it has never been observed, by either instruments or human senses. This relatively new situation, in which unobserved phenomenon come to be treated as if they had been directly observed, has lead modern physics into deep epistemological crisis of which it is not yet aware. The purpose of this article is both to identify the epistemological crisis created by this situation, as well as to present a solution to overcoming this crisis.

Claude N. Cohen-Tannoudji

Richard F. Kitchener