Searcharxiv⌕ Search

arXiv subjects

Mike D. Schneider

Publications and source records attributed to Mike D. Schneider.

11 recordsLinked to original sources

Popularity Feedback Constrains Innovation in Cultural Markets

Real-world creative processes ranging from art to science rely on social feedback-loops between selection and creation. Yet, the effects of popularity feedback on collective creativity remain poorly understood. We investigate how popularity ratings influence cultural dynamics in a large-scale online experiment where participants ($N = 1\,008$) iteratively \textit{select} images from evolving markets and \textit{produce} their own modifications. Results show that exposing the popularity of images reduces cultural diversity and slows innovation, delaying aesthetic improvements. Popularity feedback is associated with changes to both selection and creative stages. During selection, popularity information triggers cumulative advantage, with participants preferentially building upon popular images, reducing diversity. During creation, participants make less disruptive changes, and are more likely to expand existing visual patterns. Feedback loops in cultural markets thus not only shape selection, but also, directly or indirectly, the form and direction of cultural innovation.

cs.SI↗

A demonstration that classical gravity does not produce entanglement

Once again, dispute has arisen over the interpretation of proposed quantum information theory experiments to probe the quantum nature of gravity by testing for gravitationally induced entanglement (GIE) between two spatially separated massive particles ([2] vs. [16, 17]; further contributions in [11, 13]). The confusion appears to reside in interpreting applications of a Hamiltonian formalism. But classical gravity cannot mediate entanglement on independent grounds. A Newton-Cartan analysis shows that if gravity is classical, a mediator, and entanglement is observed as an outcome of performing a GIE experiment, something other than gravity must have supplied the (virtual) force needed during the experiment to produce the effect.

quant-ph↗

Spacetime emergence: an (in)effective story

Physicists and philosophers are increasingly prone to regarding our current physical theories as providing 'effective descriptions' of real-world systems. In the context of quantum gravity research, this fuels a common view that the classical spacetime theory of general relativity provides effective descriptions where it is successfully applied. That common view of general relativity, in turn, encourages an 'effective' understanding of spacetime emergence. But descriptions of spacetime in general relativity irreducibly include global physical content, which is not effective. Recognizing this fact reigns in the interpretive scope of the common view of general relativity and specifically undermines our thinking about spacetime emergence effectively.

physics.hist-ph↗

On efforts to decouple early universe cosmology and quantum gravity phenomenology

The Big Bang singularity in standard model cosmology suggests a program of study in 'early universe' quantum gravity phenomenology. Inflation is usually thought to undermine this program's prospects by means of a dynamical diluting argument, but such a view has recently been disputed within inflationary cosmology, in the form of a 'trans-Planckian censorship' conjecture. Meanwhile, trans-Planckian censorship has been used outside of inflationary cosmology to motivate alternative early universe scenarios that are tightly linked to ongoing theorizing in quantum gravity. Against the resulting trend toward early universe quantum gravity phenomenology within and without inflation, Ijjas and Steindhardt suggest a further alternative: a 'generalized cosmic censorship' principle. I contrast the generalized cosmic censorship principle with the logic of its namesake, the cosmic censorship conjectures. I also remark on foundational concerns in the effective field theory approach to cosmology beyond the standard model, which would be based on that principle.

physics.hist-ph↗

A Role for the Fauxrizon in the Semiclassical Limit of a Fuzzball

Recent work on the status of astrophysical modeling in the wake of quantum gravity indicates that a 'fauxrizon' (portmanteau of 'faux horizon'), such as is relevant to understanding astrophysical black holes according to the fuzzball proposal within string theory, might ultimately solve the familiar black hole evaporation paradox. I clarify, with general upshots for the foundations of quantum gravity research, some of what this suggestion would amount to: identification of intertheoretic constraints on global spacetime structure in (observer-relative) semiclassical models of fuzzballs.

physics.hist-ph↗

Empty space and the (positive) cosmological constant

I discuss empty space, as it appears in the physical foundations of relativistic field theories and in the semiclassical study of isolated systems. Of particular interest is the relationship between empirical measurements of the cosmological constant and the question of appropriate representation of empty space by spacetimes, or models of general relativity. Also considered is a speculative move that shows up in one corner of quantum gravity research. In pursuit of holographic quantum cosmology given a positive cosmological constant, there is evidently some freedom available for theoretical physicists to pick between two physically inequivalent spacetime representations of empty space, moving forward: de Sitter spacetime or its 'elliptic' cousin.

physics.hist-ph↗

A (strictly) contemporary perspective on trans-Planckian censorship

I critically discuss a controversial 'trans-Planckian censorship' conjecture, which has recently been introduced to researchers working at the intersection of fundamental physics and cosmology. My focus explicitly avoids any appeals to contingent research within string theory (the sociological origins of the conjecture) or regarding the more general (quantum) gravitational 'swampland'. Rather, I concern myself with the conjecture's foundations in our current, well-trodden physics of quantized fields, spacetime, and (classical) gravity. In doing so, I locate what exactly within trans-Planckian censorship amounts to a departure from current physics -- identifying what is, ultimately, so conjectural about the conjecture.

gr-qc↗

Trans-Planckian Philosophy of Cosmology

I provide some philosophical groundwork for the recently proposed 'trans-Planckian censorship' conjecture in theoretical physics. In particular, I argue that structure formation in early universe cosmology is, at least as we typically understand it, autonomous with regards to quantum gravity, the high energy physics that governs the Planck regime in our universe. Trans-Planckian censorship is then seen as a means of rendering this autonomy an empirical constraint within ongoing quantum gravity research.

physics.hist-ph↗

Would Two Dimensions be World Enough for Spacetime?

We consider various curious features of general relativity, and relativistic field theory, in two spacetime dimensions. In particular, we discuss: the vanishing of the Einstein tensor; the failure of an initial-value formulation for vacuum spacetimes; the status of singularity theorems; the non-existence of a Newtonian limit; the status of the cosmological constant; and the character of matter fields, including perfect fluids and electromagnetic fields. We conclude with a discussion of what constrains our understanding of physics in different dimensions.

physics.hist-ph↗

Anomalous Observers in the Subjectively Identical Reference Class

Anthropic reasoning is a critical tool to understand probabilities, especially in a large universe or multiverse. According to anthropic reasoning, we should consider ourselves typical among members of a reference class that must include all subjectively indistinguishable observers. We discuss here whether such a reference class, which we assume must include computer simulations, must also include computers that replay previous simulations, magnetic tapes that store but do not "run" the simulation, and even abstract mathematical functions. We do not see any clear criterion for excluding these anomalous observers, but their presence is deeply troubling to the idea of anthropic reasoning.

physics.hist-ph↗