Both arrows of time are possible microscopically

Sabine Hossenfelder comments in her Youtube talk (see this) about the recent theoretical claim that microscopically both arrows of time are possible.  In the article "Emergence of opposing arrows of time in open quantum systems" (see this), Thomas Guff, Chintalpati Umashankar Shastry, Andrea Rocco  argue that  the thermodynamic arrow of time can be understood as a property of the initial state without assuming that that it is assumed at the level of dynamics as usually believe. This means that at the microscopic level both arrows of time are allowed.

It seems that the time is becoming mature for TGD: TGD indeed predicts that both arrows of time are possible non only in microscopic, but also  macroscopic, scales.   Zero energy ontology (ZEO) is the quantum ontology of TGD,  implied by the new view of space-time as a 4-surface.  In  TGD  point-like particles are replaced with 3-surfaces rather than strings.

General coordinate invariance without a mathematically non-existing path integral requires holography and  classical physics becomes an exact part of quantum physics. Space-time surfaces become   analogs of Bohr orbits for 3-surfaces as particles  and classical physics represents an exact part of  quantum physics. 

Holography= holomorphy principle allows to reduce field equations to minimal surface  equations for any action as long as it is general coordinate invariance and constructible in terms of the induced geometry. Hence the classical theory is universal.  Remarkably, the holography is slightly non-deterministic. 

 Quantum states are now quantum superpositions of Bohr orbits rather than 3-surfaces and  this  solves the basic problem of quantum measurement theory.  Space-time surfaces are located inside causal diamonds CD=cd×CP₂, where cd is a causal diamond of M⁴.  The cds form a scale hierarchy and CD has interpretation as a counterpart for the perceptive field of a self, defined by the superposition of Bohr orbits changing in "small" state function reductions (SSFRs), which define the TGD counterpart for the sequence of measurements of the same observables in standard QM. In TGD, the Zeno effect means   that the 3-D states and 3-surfaces at the passive boundary (PA) of CD do not change in the sequence of SSFRs. They however change at  the active boundary (AB) of CD (since the superpositions of  Bohr orbits (4-D minimal surfaces) made possible by the slight classical non-determinism  change present already for 2-D minimal surfaces.  This gives rise to a conscious entity sel having CD as its perceptive field.

CD  increases in a statistical sense during the sequence of SSFRs and this gives a correlation between the subjective time  of self defined by the sequence of SSFRs and  the geometric time defined by the distance between the tips of the CD.

Either boundary of the CD can be   passive.  In "big" SFRS (BSFRs) as counterparts of ordinary SFRs, the roles of PB and AB change and the arrow of geometric time changes. This can occur   on all scales.  In the article motivating the Youtube talk this is claimed to happen in microscopic scales.

The number theoretic view of TGD   predicts an entire hierarchy of effective Planck constants and therefore quantum coherence becomes possible in all scales. Also the  arrow of time can change  in even macroscopic scales.  

In  TGD inspired theory of consciousness,  this allows us to interpret the sleep state as a state with a non-standard arrow of time. We do not remember anything from the period of deep sleep since the classical signals traveling in the wrong direction of time do not reach us the next day. Roughly, one half of the Universe is sleeping and wake-up and sleep periods characterize all systems even in cosmological scales. Biological death is also falling in sleep but on a longer time scale and with more dramatic consequences.

See  for instance  the articles   TGD as it is towards end of 2024: part I, TGD as it is towards end of 2024: part II, and Some comments related to Zero Energy Ontology (ZEO).