Holography without holography: How to turn inter-representational into intra-theoretical relations in AdS/CFT

Abstract

We show by means of the AdS/CFT correspondence in the context of quantum gravity how inter-representational relations-loosely speaking relations among different equivalent representations of one and the same physics-can play out as a tool for intra-theoretical developments and thus boost theory development in the context of discovery. More precisely, we first show that, as a duality, the AdS/CFT correspondence cannot in itself testify to the quantum origin of gravity (though it may be utilized for this purpose). We then establish through two case studies from emergent gravity (Jacobson (2016), Verlinde (2017)) that the holographic AdS/CFT correspondence can, however, still excel as a guiding principle towards the quantum origin of gravity (similar in nature to quantisation).

AdS/CFT beyond inter-representational dualities

“…Furthermore, the QECC framework suggests that a logical and fundamental theory is given on the AdS side. If the original 'inter-representational' view of AdS/CFT [17] is also correct, then the logical theory has the CFT dual. This implies that the logical sector of the effective CFT is also CFT!…”

“…While the points made in [17] regarding the AdS/CFT correspondence are mainly addressed, this paper is intended to be a conceptual review (avoiding unnecessary math as much as possible) of recent developments in holographic gravity as well -holography of information [18,12,27,26,23] and the islands proposal [15,2,5,7,4], as well as critiques of these views [21,29,14,9]. These developments and criticisms suggest that there are conceptual disagreements regarding what AdS/CFT is supposed to mean, despite a relative lack of discussions about them.…”

“…• Is the Hilbert space of dual CFT greater than that of string theory? The islands proposal (or more generally, quantum error-correcting code view, the QECC view [15,1]) says this is so, while the traditional view suggests string theory on AdS and its dual CFT on AdS boundary to be exactly the same theory on the same Hilbert space [17,9]. The islands proposal keeps both CFT and string theory to be local theories, but consider CFT to be heavily redundant with regards to bulk information.…”

“…Can fundamental questions that cannot be answered in string theory be addressed in its dual CFT? The traditional view would doubt this possibility, since AdS/CFT is only a inter-representational duality, as stated in [17]. But some recent applications of AdS/CFT start from CFT and then apply bulk reconstruction [15].…”

A Comprehensive Overview of Photon-Proton Scattering and QCD Methodology

“…Although it requires a lot of time and resources, the method has a wide range of applications and provides access to areas of the theory not otherwise possible, particularly the clearly defined forces operating between quark and antiquark in a meson. However, the challenge is to explore QCD at significant density and low energy using lattice techniques because of the quantitative sign problem e.g., nuclear matter or the interior of neutron stars [42].…”