Some modern cosmological models predict the appearance of Boltzmann Brains: observers who randomly fluctuate out of a thermal bath rather than naturally evolving from a low-entropy Big Bang. A theory in which most observers are of the Boltzmann Brain type is generally thought to be unacceptable, although opinions differ. I argue that such theories are indeed unacceptable: the real problem is with fluctuations into observers who are locally identical to ordinary observers, and their existence cannot be swept under the rug (...) by a choice of probability distributions over observers. The issue is not that the existence of such observers is ruled out by data, but that the theories that predict them are cognitively unstable: they cannot simultaneously be true and justifiably believed. (shrink)

A non-technical introduction to quantum mechanics, the Everett interpretation, and the emergence of spacetime.

We have a much better understanding of physics than we do of consciousness. I consider ways in which intrinsically mental aspects of fundamental ontology might induce modifications of the known laws of physics, or whether they could be relevant to accounting for consciousness if no such modifications exist. I suggest that our current knowledge of physics should make us skeptical of hypothetical modifications of the known rules, and that without such modifications it’s hard to imagine how intrinsically mental aspects could (...) play a useful explanatory role. Draft version of a paper submitted to Journal of Consciousness Studies, special issue responding to Philip Goff’s Galileo’s Error: Foundations for a New Science of Consciousness. (shrink)

This book provides an account of the nature of time, especially time's arrow and the role of entropy, at a semi-popular level. Special attention is given to statistical mechanics, the past hypothesis, and possible cosmological explanations thereof.

I discuss "Poetic Naturalism" -- there is only one world, the natural world, but there are many ways of talking about it -- both as a general concept, and how it accounts for our actual world. I talk about emergence, fundamental physics, entropy and complexity, the origins of life and consciousness, and moral constructivism.

I defend the extremist position that the fundamental ontology of the world consists of a vector in Hilbert space evolving according to the Schrödinger equation. The laws of physics are determined solely by the energy eigenspectrum of the Hamiltonian. The structure of our observed world, including space and fields living within it, should arise as a higher-level emergent description. I sketch how this might come about, although much work remains to be done.

It is commonplace in discussions of modern cosmology to assert that the early universe began in a special state. Conventionally, cosmologists characterize this fine-tuning in terms of the horizon and flatness problems. I argue that the fine-tuning is real, but these problems aren't the best way to think about it: causal disconnection of separated regions isn't the real problem, and flatness isn't a problem at all. Fine-tuning is better understood in terms of a measure on the space of trajectories: given (...) reasonable conditions in the late universe, the fraction of cosmological histories that were smooth at early times is incredibly tiny. This discussion helps clarify what is required by a complete theory of cosmological initial conditions. (shrink)

To the best of our current understanding, quantum mechanics is part of the most fundamental picture of the universe. It is natural to ask how pure and minimal this fundamental quantum description can be. The simplest quantum ontology is that of the Everett or Many-Worlds interpretation, based on a vector in Hilbert space and a Hamiltonian. Typically one also relies on some classical structure, such as space and local configuration variables within it, which then gets promoted to an algebra of (...) preferred observables. We argue that even such an algebra is unnecessary, and the most basic description of the world is given by the spectrum of the Hamiltonian and the components of some particular vector in Hilbert space. Everything else—including space and fields propagating on it—is emergent from these minimal elements. (shrink)

Cosmological models that invoke a multiverse - a collection of unobservable regions of space where conditions are very different from the region around us - are controversial, on the grounds that unobservable phenomena shouldn't play a crucial role in legitimate scientific theories. I argue that the way we evaluate multiverse models is precisely the same as the way we evaluate any other models, on the basis of abduction, Bayesian inference, and empirical success. There is no scientifically respectable way to do (...) cosmology without taking into account different possibilities for what the universe might be like outside our horizon. Multiverse theories are utterly conventionally scientific, even if evaluating them can be difficult in practice. (shrink)

Graduate-level textbook in general relativity.

It seems natural to ask why the universe exists at all. Modern physics suggests that the universe can exist all by itself as a self-contained system, without anything external to create or sustain it. But there might not be an absolute answer to why it exists. I argue that any attempt to account for the existence of something rather than nothing must ultimately bottom out in a set of brute facts; the universe simply is, without ultimate cause or explanation.

We study the question of how to decompose Hilbert space into a preferred tensor-product factorization without any pre-existing structure other than a Hamiltonian operator, in particular the case of a bipartite decomposition into "system" and "environment." Such a decomposition can be defined by looking for subsystems that exhibit quasi-classical behavior. The correct decomposition is one in which pointer states of the system are relatively robust against environmental monitoring (their entanglement with the environment does not continually and dramatically increase) and remain (...) localized around approximately-classical trajectories. We present an in-principle algorithm for finding such a decomposition by minimizing a combination of entanglement growth and internal spreading of the system. Both of these properties are related to locality in different ways. This formalism could be relevant to the emergence of spacetime from quantum entanglement. (shrink)

We study the conservation of energy, or lack thereof, when measurements are performed in quantum mechanics. The expectation value of the Hamiltonian of a system changes when wave functions collapse in accordance with the standard textbook treatment of quantum measurement, but one might imagine that the change in energy is compensated by the measuring apparatus or environment. We show that this is not true; the change in the energy of a state after measurement can be arbitrarily large, independent of the (...) physical measurement process. In Everettian quantum theory, while the expectation value of the Hamiltonian is conserved for the wave function of the universe, it is not constant within individual worlds. It should therefore be possible to experimentally measure violations of conservation of energy, and we suggest an experimental protocol for doing so. (shrink)

We provide a derivation of the Born Rule in the context of the Everett (Many-Worlds) approach to quantum mechanics. Our argument is based on the idea of self-locating uncertainty: in the period between the wave function branching via decoherence and an observer registering the outcome of the measurement, that observer can know the state of the universe precisely without knowing which branch they are on. We show that there is a uniquely rational way to apportion credence in such cases, which (...) leads directly to the Born Rule. Our analysis generalizes straightforwardly to cases of combined classical and quantum self-locating uncertainty, as in the cosmological multiverse. (shrink)

I propose a version of quantum mechanics featuring a discrete and finite number of states that is plausibly a model of the real world. The model is based on standard unitary quantum theory of a closed system with a finite-dimensional Hilbert space. Given certain simple conditions on the spectrum of the Hamiltonian, Schrödinger evolution is periodic, and it is straightforward to replace continuous time with a discrete version, with the result that the system only visits a discrete and finite set (...) of state vectors. The biggest challenges to the viability of such a model come from cosmological considerations. The theory may have implications for questions of mathematical realism and finitism. (shrink)

Effective Field Theory (EFT) is the successful paradigm underlying modern theoretical physics, including the "Core Theory" of the Standard Model of particle physics plus Einstein's general relativity. I will argue that EFT grants us a unique insight: each EFT model comes with a built-in specification of its domain of applicability. Hence, once a model is tested within some domain (of energies and interaction strengths), we can be confident that it will continue to be accurate within that domain. Currently, the Core (...) Theory has been tested in regimes that include all of the energy scales relevant to the physics of everyday life (biology, chemistry, technology, etc.). Therefore, we have reason to be confident that the laws of physics underlying the phenomena of everyday life are completely known. (shrink)

In Morality & Mathematics, Justin Clarke-Doane argues that it is hard to imagine being "a realist about, for example, the standard model of particle physics, but not about mathematics." I try to explain how that seems very possible from the perspective of a physicist. What is real is the physical world; mathematics starts from descriptions of the natural world and extrapolates from there, but that extrapolation does not imply any independent reality. -/- Submitted to an Analysis Reviews symposium on Clarke-Doane's (...) Morality & Mathematics. (shrink)

I ask whether what we know about the universe from modern physics and cosmology, including fine-tuning, provides compelling evidence for the existence of God, and answer largely in the negative.

A longstanding issue in attempts to understand the Everett (Many-Worlds) approach to quantum mechanics is the origin of the Born rule: why is the probability given by the square of the amplitude? Following Vaidman, we note that observers are in a position of self-locating uncertainty during the period between the branches of the wave function splitting via decoherence and the observer registering the outcome of the measurement. In this period it is tempting to regard each branch as equiprobable, but we (...) argue that the temptation should be resisted. Applying lessons from this analysis, we demonstrate (using methods similar to those of Zurek's envariance-based derivation) that the Born rule is the uniquely rational way of apportioning credence in Everettian quantum mechanics. In doing so, we rely on a single key principle: changes purely to the environment do not affect the probabilities one ought to assign to measurement outcomes in a local subsystem. We arrive at a method for assigning probabilities in cases that involve both classical and quantum self-locating uncertainty. This method provides unique answers to quantum Sleeping Beauty problems, as well as a well-defined procedure for calculating probabilities in quantum cosmological multiverses with multiple similar observers. (shrink)

Science and religion both make claims about the fundamental workings of the universe. Although these claims are not a priori incompatible (we could imaginebeing brought to religious belief through scientific investigation), I will argue that in practice they diverge. If we believe that the methods of science can be used to discriminate between fundamental pictures of reality, we are led to a strictly materialist conception of the universe. While the details of modern cosmology are not a necessary part of this (...) argument, they provide interesting clues as to how an ultimate picture may be constructed. (shrink)

We argue that, under certain plausible assumptions, de Sitter space settles into a quiescent vacuum in which there are no dynamical quantum fluctuations. Such fluctuations require either an evolving microstate, or time-dependent histories of out-of-equilibrium recording devices, which we argue are absent in stationary states. For a massive scalar field in a fixed de Sitter background, the cosmic no-hair theorem implies that the state of the patch approaches the vacuum, where there are no fluctuations. We argue that an analogous conclusion (...) holds whenever a patch of de Sitter is embedded in a larger theory with an infinite-dimensional Hilbert space, including semiclassical quantum gravity with false vacua or complementarity in theories with at least one Minkowski vacuum. This reasoning provides an escape from the Boltzmann brain problem in such theories. It also implies that vacuum states do not uptunnel to higher-energy vacua and that perturbations do not decohere while slow-roll inflation occurs, suggesting that eternal inflation is much less common than often supposed. On the other hand, if a de Sitter patch is a closed system with a finite-dimensional Hilbert space, there will be Poincaré recurrences and dynamical Boltzmann fluctuations into lower-entropy states. Our analysis does not alter the conventional understanding of the origin of density fluctuations from primordial inflation, since reheating naturally generates a high-entropy environment and leads to decoherence, nor does it affect the existence of non-dynamical vacuum fluctuations such as those that give rise to the Casimir effect. (shrink)

This chapter contains sections titled: Notes.

An award-wining biologist takes us on the dramatic expeditions that unearthed the history of life on our planet. Just 150 years ago,most of our world was an unexplored wilderness.Our sense of how old it was? Vague and vastly off the mark. And our sense of our own species’ history? A set of fantastic myths and fairy tales. Fossils had been known for millennia, but they were seen as the bones of dragons and other imagined creatures. In the tradition of The (...) Microbe Hunters and Gods, Graves, and Scholars, Sean Carroll’s Remarkable Creatures celebrates the pioneers who replaced our fancies with the even more amazing true story of how our world evolved. Carroll recounts the most important discoveries in two centuries of national history — from Darwin’s trip around the world to CharlesWalcott’s discovery of pre-Cambrian life in the Grand Canyon; from Louis and Mary Leakey’s investigation of our deepest past in East Africa to the trailblazers in modern laboratories who have located a time clock in our DNA. Join him in a rousing voyage of discovery, from the epic journeys of pioneering naturalists to the breakthroughs making headlines today. (shrink)

The Principle of Sufficient Reason (PSR) holds that, for everything that exists or occurs or holds true, there is a reason why that is the case. I consider three possible ways of relating physics to the PSR: past states as reasons for present states, reasons why the laws of physics take the form that they do, and reasons why there is anything at all. In each case I suggest that the PSR is not the best way of thinking about how (...) and why physics works. -/- Invited reflection for The Principle of Sufficient Reason (Oxford Philosophical Concepts), Eds. F. Amijee and M. Della Rocca (forthcoming 2024). (shrink)

The appendages of the adult fruit fly and other insects and Arthropods develop from secondary embryonic fields that form after the primary anterior/posterior and dorsal/ventral axes of the embryo have been determined. In Drosophila, the position and fate of the different fields formed within each segment are determined by genes acting along both embryonic axes, within individual segments, and within specific fields. Since the major architectural differences between most Arthropod classes and orders involve variations in the number, type and morphology (...) of body appendages, the elucidation of the embryology and molecular genetics of the origin and patterning of insect limb fields may help to facilitate an understanding of both the mechanism of appendage formation and some of the major steps in the morphological evolution of the Arthropods. In this review, we will discuss recent studies that have advanced our understanding of both the origin and patterning of Drosophila leg and wing secondary fields. These results provide fresh insights into potentially general mechanisms of how body parts develop and evolve. (shrink)

Evolutionary changes in traits that affect both ecological divergence and mating signals could lead to reproductive isolation and the formation of new species. Insect cuticular hydrocarbons (CHCs) are potential examples of such dual traits. They form a waxy layer on the cuticle of the insect to maintain water balance and prevent desiccation, while also acting as signaling molecules in mate recognition and chemical communication. Because the synthesis of these hydrocarbons in insect oenocytes occurs through a common biochemical pathway, natural or (...) sexual selection on one role may affect the other. In this review, we explore how ecological divergence in insect CHCs can lead to divergence in mating signals and reproductive isolation. We suggest that the evolution of insect CHCs may be ripe models for understanding ecological speciation. (shrink)

Sean Carroll argues that we should endorse atheism since there are no good reasons for affirming the more complex thesis of theism over the less complexthesis of materialism. However, this argument relies on an epistemological minimalism we should reject.

Physicist Sean Carroll has developed a new theory of the fundamental nature of reality, which he calls “Poetic Naturalism,” with the stated goal of developing a theory of what is real that is consistent with the findings of natural science. Carroll claims to prove that morality cannot be seen as objectively true. This essay argues that Carroll's conclusion is not convincing; there is no good reason to reject moral objectivity within a purely naturalistic worldview.

Sean B. Carroll’s new book, The Serengeti Rules: The Quest to Discover How Life Works and Why it Matters, is a well-written mix of history of science and philosophy of biology. In his book, Carroll articulates a set of ecological generalisations, the Serengeti Rules, which are supposed to make salient the structures in ecosystems that ensure the persistence of those ecosystems. In this essay review, I evaluate Carroll’s use of the controversial concept of regulation and his (...) thesis that ecosystems have a natural balance comparable to that of human bodies. My conclusion is optimistic. Carroll’s generalisations provide a tool-kit for building relatively simple models that are accurate enough to be widely applied in experimental ecology and conservation science, guiding interventions upon unhealthy ecosystems. (shrink)

I argue that the Carroll-Chen cosmogonic model does not provide a plausible scientific explanation of our universe's initial low-entropy state.

This paper offers an unorthodox appraisal of empirical research bearing on the question of the low representation of women in philosophy. It contends that fashionable views in the profession concerning implicit bias and stereotype threat are weakly supported, that philosophers often fail to report the empirical work responsibly, and that the standards for evidence are set very low—so long as you take a certain viewpoint.

Introduction: liberal-rationalism and the progress model i This study stands primarily as an essay in morals. It is governed by Nietzsche's contention that ...

Discussion and debate on stakeholder theory continues unabated, but not a lot of people know that it first began in Finland in the 1960s, as this report of a recent Conference there shows. Archie B. Carroll, the well‐known writer on corporate social responsibility, is Robert W. Scherer Professor of Management at the University of Georgia, Athens, GA, USA (e‐mail [email protected]); and Juha Näsi is Professor of Management at the University of Jyväskylä, Jyväskylä, Finland.

This article explores the extent to which three models of management morality – Immoral Management, Moral Management, and Amoral Management – are extant in the European business environment. After a brief introduction and presentation of examples of each model, a further description of each model and European applications are outlined. Two possible hypotheses regarding the models’ presence in European business are presented and then concluding observations are made.

A common finding in the study of emotion and decision making is the tendency for fear and anxiety to decrease risk taking. The current meta-analysis summarises the strength and variability of this...

Are there illusions of duration? Certainly, many experiences of an event’s duration differ from its measure in clock duration, the measure of that event in seconds, minutes, hours, and so forth. However, I argue that an illusory duration requires more than difference from a real duration; it requires difference from a duration that is relevant to experience. It is plausible to hold that there are many kinds of real duration and reason to question the relevance of all of them. In (...) particular, the interpretation of experienced duration as illusory is typical because it is compared to clock time; the experience of duration goes wrong by being different from a clock measurement of duration. However, I argue that clock duration is not obviously relevant to evaluating the experience of duration.In response, one might hold that it is plausible to evaluate experience by clock duration because clocks more closely match reality than experiences do; on the scale of experience, clock time is no different to real duration. It is not that experienced duration is an illusion because it is merely different from clock duration; it is an illusion because it is different from real duration and we know this because of its difference from clock duration. It is like illusions of size: some object seems to be a size it is not and we know this by comparing it to an object we can otherwise accurately measure by meters.However, unlike size illusions, it is not clear what the ‘real duration’ is against which we should evaluate apparent duration. What is meant by ‘real duration’ involves either an appeal to the duration of substantial absolute time or some kind of duration in things, for example, duration which is the measure of change in some kind of process. is an irrelevant duration; few positions hold that we experience absolute time. As for, if real duration is a measure of change, then, for experienced duration to match clock duration, they must both agree on the relevant change. If there is a difference in what is treated as the real duration, then neither experience nor clocks can be treated as evaluable in terms of the other.Finally, we may have an illusory duration because there are cases of variation between experiences of the same duration. Yet, even here, we may be misled; we may not be directly comparing experiences. We compare the experienced durations through first measuring each in terms of clock duration. If there is a variability in the relationship between clock standard and some relevant standard for experience, then one expects anything accurately meeting one standard to differ from anything accurately meeting the other. The error is holding there is a stable relationship between the standards. This error is not a matter of our experience of duration, and so is not an illusion of duration. (shrink)

What makes something a part of my body, for moral purposes? Is the body defined naturalistically: by biological relations, or psychological relations, or some combination of the two? This paper approaches this question by considering a borderline case: the status of prostheses. I argue that extant accounts of the body fail to capture prostheses as genuine body parts. Nor, however, do they provide plausible grounds for excluding prostheses, without excluding some paradigm organic parts in the process. I conclude by suggesting (...) that embodiment is moralized all the way down: to be a body part is to be the sort of thing that ought to be protected, in a certain way, by social practices. (shrink)

Companies offer ethics codes and training to increase employees' ethical conduct. These programs can also enhance individual work attitudes because ethical organizations are typically valued. Socially responsible companies are likely viewed as ethical organizations and should therefore prompt similar employee job responses. Using survey information collected from 313 business professionals, this exploratory study proposed that perceived corporate social responsibility would mediate the positive relationships between ethics codes/training and job satisfaction. Results indicated that corporate social responsibility fully or partially mediated the (...) positive associations between four ethics program variables and individual job satisfaction, suggesting that companies might better manage employees' ethical perceptions and work attitudes with multiple policies, an approach endorsed in the ethics literature. (shrink)

I argue here that our rights in our bodies are not well explained by self-ownership – and thus, also, that we cannot infer any further distributive implications of self-ownership from intuitions about body rights via inference to the best explanation. And I sketch an alternative view, on which we do indeed own our bodies, but not because we own ourselves. Self-ownership, I argue, provides a satisfying explanation only if we take it seriously: not as a mere metaphor, but as an (...) expression of a literal, reflexive ownership relation between me and myself, whatever I myself am. I go on to canvas the most prominent theories of what human beings like me literally are, arguing that each of these theories makes it hard to see how our self-ownership can ground our rights in our bodies. In the second half I consider and refine alternative, interest-based, explanations of our rights in our bodies, drawing on suggestions in this direction from Kasper Lippert-Rasmussen and Alan Wertheimer. I show how it is possible in principle to affirm that body ownership rights remain (in a sense) natural rights, even on the sort of interest-based view of ownership that many (including myself) take to preclude all or most fully natural property rights. I argue that many body rights can be grounded prefiguratively, in facts about the possible emergence of sufficiently just authority-assigning practices, rather than (as with most property rights) in their actual existence. Finally, I return to the distributive issues that motivated much interest in self-ownership in the first place – particularly, the question of whether and in what way our rights in our bodies generate rights in other things, by labor or otherwise. Without actually answering this question, I show how the account developed here would proceed in doing so: not by positing body rights as a methodologically prior constraint on rights of other kinds, but rather by considering the implications entire systems of rights and duties have for the interests of those who possess and are bound by them. (shrink)

A number of authors have argued recently that the content of perceptual experience can, and even must, be characterized in conceptual terms. Their claim, more precisely, is that every perceptual experience is such that, of necessity, its content is constituted entirely by concepts possessed by the subject having the experience. This is a surprising result. For it seems reasonable to think that a subject’s experiences could be richer and more fine-grained than his conceptual repertoire; that a subject might be able, (...) for example, to discriminate in experience more shades of colors than he has color concepts. The key move in their argument, therefore, is to articulate the conceptual content of experience using demonstrative, instead of general, concepts. For instance, these authors argue that the content of my perceptual experience of a particular shade of green is properly characterized in terms of the concept expressed by the linguistic utterance “that shade”. Even if I don’t possess a general concept for the shade I’m seeing—a concept of the kind typically expressed using color names like ‘chartreuse’ or ‘lime’—nevertheless, these authors argue, the content of the experience can still be characterized conceptually using a demonstrative concept that I do possess. (shrink)

In this paper I develop an account of member obligation: the obligations that fall on the members of an obligated collective in virtue of that collective obligation. I use this account to argue that unorganized collections of individuals can constitute obligated agents. I argue first that, to know when a collective obligation entails obligations on that collective’s members, we have to know not just what it would take for each member to do their part in satisfying the collective obligation, but (...) also what they should do if they cannot do their part because others will not do theirs. I go on to argue (contra recent proposals) that it is not good enough for members in this situation to reasonably believe that others will not do their part. Rather, for a member of an obligated collective to permissibly escape doing her part in a collective obligation, she must both reasonably doubt that others will do their part and stand ready to act in case others do as well. -/- This necessary condition for collective obligation points the way to plausible sufficient conditions – conditions that, I argue, allow unstructured collectives to bear obligations. For (a) if a collective’s members are individually obligated to be ready to do their part, in a given collective action, and (b) if that individual readiness makes it sufficiently likely that the collective will in fact act, then it is hard to see what could block an attribution of collective obligation. In particular, in that case there ought to be no additional objection that there is no existing, organized “agent” on which the obligation might fall. For agents are, simply, things that can act. To be able to act is just to be able to succeed by trying. Unstructured collectives try to do something, I argue, when each member acts on their willingness to do their part in that thing if others do theirs; sometimes they succeed, producing a collective action. Some unstructured collectives, therefore, can succeed by trying; therefore, they can act; therefore they are agents. (shrink)

A number of authors have argued recently that the content of perceptual experience can, and even must, be characterized in conceptual terms. Their claim, more precisely, is that every perceptual experience is such that, of necessity, its content is constituted entirely by concepts possessed by the subject having the experience. This is a surprising result. For it seems reasonable to think that a subject’s experiences could be richer and more fine-grained than his conceptual repertoire; that a subject might be able, (...) for example, to discriminate in experience more shades of colors than he has color concepts. The key move in their argument, therefore, is to articulate the conceptual content of experience using demonstrative, instead of general, concepts. For instance, these authors argue that the content of my perceptual experience of a particular shade of green is properly characterized in terms of the concept expressed by the linguistic utterance “that shade”. Even if I don’t possess a general concept for the shade I’m seeing—a concept of the kind typically expressed using color names like ‘chartreuse’ or ‘lime’—nevertheless, these authors argue, the content of the experience can still be characterized conceptually using a demonstrative concept that I do possess. (shrink)

Ethics training is commonly cited as a primary method for increasing employees' ethical decision making and conduct. However, little is known about how the presence of ethics training can enhance other components of an organization's ethical environment such as employees' perception of company ethical values. Using a national sample of 313 business professionals employed in the United States, the relationship between ethics training and perceived organizational ethics was explored. The results of the analysis provide significant statistical support for the notion (...) that businesspersons employed in organizations that have formalized ethics training programs have more positive perceptions of their companies' ethical context than do individuals employed in organizations that do not. The analysis also indicated that job satisfaction was related to employees' attitudes about their ethical context. The managerial implications of the results are outlined, along with the limitations of the study and recommendations for future research. (shrink)