Persistence And Spacetime

How do material objects persist through time and survive change? Are they three-dimensional entities extended in space, or are they four-dimensional spacetime 'worms'? Balashov shows how the theory of relativity supports four-dimensionalism and in so doing illuminates a wide range of metaphysical issues.

Material objects persist through time and survive change. How do they manage to do so? What are the underlying facts of persistence? Do objects persist by being "wholly present" at all moments of time at which they exist? Or do they persist by having distinct "temporal segments" confined to the corresponding times? Are objects three-dimensional entities extended in space, but not in time? Or are they four-dimensional spacetime "worms"? These are matters of intense debate, which is now driven by concerns about two major issues in fundamental ontology: parthood and location. It is in this context that broadly empirical considerations are increasingly brought to bear on the debate about persistence. Persistence and Spacetime pursues this empirically based approach to the questions. Yuri Balashov begins by setting out major rival views of persistence -- endurance, perdurance, and exdurance -- in a spacetime framework and proceeds to investigate the implications of Einstein's theory of relativity for the debate about persistence. His overall conclusion -- that relativistic considerations favour four-dimensionalism over three-dimensionalism -- is hardly surprising. It is, however, anything but trivial. Contrary to a common misconception, there is no straightforward argument from relativity to four-dimensionalism. The issues involved are complex, and the debate is closely entangled with a number of other philosophical disputes, including those about the nature and ontology of time, parts and wholes, material constitution, causation and properties, and vagueness.

Material objects persist through time and survive change. How do they manage to do so? What are the underlying facts of persistence? Do objects persist by being "wholly present" at all moments of time at which they exist? Or do they persist by having distinct "temporal segments" confined to the corresponding times? Are objects three-dimensional entities extended in space, but not in time? Or are they four-dimensional spacetime "worms"? These are matters of intense debate, which is now driven by concerns about two major issues in fundamental ontology: parthood and location. It is in this context that broadly empirical considerations are increasingly brought to bear on the debate about persistence. Persistence and Spacetime pursues this empirically based approach to the questions. Yuri Balashov begins by setting out major rival views of persistence — endurance, perdurance, and exdurance — in a spacetime framework and proceeds to investigate the implications of Einstein's theory of relativity for the debate about persistence. His overall conclusion — that relativistic considerations favour four-dimensionalism over three-dimensionalism — is hardly surprising. It is, however, anything but trivial. Contrary to a common misconception, there is no straightforward argument from relativity to four-dimensionalism. The issues involved are complex, and the debate is closely entangled with a number of other philosophical disputes, including those about the nature and ontology of time, parts and wholes, material constitution, causation and properties, and vagueness.

Relativity still challenges the philosophy of time: Although several sophisticated theories of temporal existence and persistence have been developed in the last decades, there is still an ongoing debate about how to apply the various concepts to spacetime theories and about whether those distinctions are even relevant at all for the ontology of spacetime. As it turns out to be the case, the ontologists of spacetime physics could broadly be arranged into two different camps: The first group is concerned with the apparently central question in the philosophy of (space-)time, i.e., whether the present is ontologically distinguished. The second deals with the problem of temporal change: Material objects persist through (space-)time and survive change - how do they manage to do so? Both debates have reached a high level of specialized, even "overspecialized", discourse and need to be interrelated. Accordingly, the main purpose of this volume is to bring together "temporal existence" and "persistence" in spacetime.

Four-Dimensionalism defends the thesis that the material world is composed of temporal as well as spatial parts. This defense includes a novel account of persistence over time, new arguments in favour of the four-dimensional ontology, and responses to the challenges four-dimensionalism faces.Theodore Sider pays particular attention to the philosophy of time, including a strong series of arguments against presentism, the thesis that only the present is real. Arguments offered in favour of four-dimensionalism include novel arguments based on time travel, the debate beween spacetime substantivalists and relationalists, and vagueness. Also included is a comprehensive discussion of the paradoxes of coinciding material objects, and a novel resolution of those paradoxes based on temporalcounterpart theory. In conclusion Sider replies to prominent objections to four-dimensionalism, including discussion of the problem of the rotating homogenous disk.Four Dimensionalism is an original and highly readable study of the metaphysics of time and identity.

The sixteen papers collected in this volume are expanded and revised versions of talks delivered at the Second International Conference on the Ontology of Spacetime, organized by the International Society for the Advanced Study of Spacetime (John Earman, President) at Concordia University (Montreal) from 9 to 11 June 2006. Most chapters are devoted to subjects directly relating to the ontology of spacetime. The book starts with four papers that discuss the ontological status of spacetime and the processes occurring in it from a point of view that is first of all conceptual and philosophical. The focus then slightly shifts in the five papers that follow, to considerations more directly involving technical considerations from relativity theory. After this, Time, Becoming and Change take centre stage in the next five papers. The book ends with two excursions into relatively uncharted territory: a consideration of the status of Kaluza-Klein theory, and an investigation of possible relations between the nature of spacetime and condensed matter physics, respectively. Space and time in present-day physics and philosophy Relatively low level of technicality, easily accessible Introduction from scratch of the debates surrounding time Broad spectrum of approaches, coherently represented

This book contains selected papers from the First International Conference on the Ontology of Spacetime. Its fourteen chapters address two main questions: first, what is the current status of the substantivalism/relationalism debate, and second, what about the prospects of presentism and becoming within present-day physics and its philosophy? The overall tenor of the four chapters of the book’s first part is that the prospects of spacetime substantivalism are bleak, although different possible positions remain with respect to the ontological status of spacetime. Part II and Part III of the book are devoted to presentism, eternalism, and becoming, from two different perspectives. In the six chapters of Part II it is argued, in different ways, that relativity theory does not have essential consequences for these issues. It certainly is true that the structure of time is different, according to relativity theory, from the one in classical theory. But that does not mean that a decision is forced between presentism and eternalism, or that becoming has proved to be an impossible concept. It may even be asked whether presentism and eternalism really offer different ontological perspectives at all. The writers of the last four chapters, in Part III, disagree. They argue that relativity theory is incompatible with becoming and presentism. Several of them come up with proposals to go beyond relativity, in order to restore the prospects of presentism. · Space and time in present-day physics and philosophy · Introduction from scratch of the debates surrounding time · Broad spectrum of approaches, coherently represented

The nature of space and time is one of the most fascinating and fundamental philosophical issues which presently engages at the deepest level with physics. During the last thirty years this notion has been object of an intense critical review in the light of new scientific theories which try to combine the principles of both general relativity and quantum theory—called theories of quantum gravity. This book considers the way string theory shapes its own account of spacetime disappearance from the fundamental level.