相关论文: Time machine (1988--2001)

A time machine that sends information back to the past may, in principle, be built using closed time-like curves. However, the realization of a time machine must be congruent with apparent paradoxes that arise from traveling back in time.…

There is a deep structural link between acausal spacetimes and quantum theory. As a consequence quantum theory may resolve some "paradoxes" of time travel. Conversely, non-time-orientable spacetimes naturally give rise to electric charges…

This paper examines the distinct lack of clear examples of time-travellers and proposes an explanation for their absence without assuming technical barriers to constructing time machines. Instead, it develops and then analyses a model of…

This note is the written version of conversations with young colleagues on unofficial history, general ideas, unexpected facts and open problems concerning tilting theory.

Time machines are predictions of Einstein's theory of general relativity and provide a myriad of unsolved paradoxes. Convincing and general arguments against time machines and their paradoxes are missing in physics and philosophy so far. In…

This is a structured compilation of some of my favourite open problems.

The article surveys a little of the history of the technology, sets out the main current theoretical approaches in brief, and discusses the on-going opposition between theoretical and empirical approaches. It illustrates the situation with…

Whenever one has witnessed some event and then sees it reported in the media, one's reaction is the same: "it was not quite like that". It is in this spirit of a frequent first-hand witness that I write this article. I discuss a few…

The intriguing suggestion of Tegmark (1996) that the universe--contrary to all our experiences and expectations--contains only a small amount of information due to an extremely high degree of internal symmetry is critically examined. It is…

This paper has been retracted, for obvious reasons.

Discussion of some aspects of the concept of time for a general audience: nature of time, A- and B-series, time in physics, the "now", measurement of time, definition of time units, time's arrow, relativity of time, relativity of…

Widespread and extensive use of computers and their interconnections in almost all sectors like communications, finance, transportation, military, governance, education, energy etc., have made them attractive targets for adversaries to spy,…

A brief history, the current state, and future directions of spin mechanics are presented.

Relativistic quantum information combines the informational approach to understanding and using quantum mechanics systems - quantum information - with the relativistic view of the universe. In this introductory review we examine key results…

An annotated bibliography of papers which deal with or use Abstract State Machines (ASMs), as of January 1998.

We provide an overview of theories of continuous time computation. These theories allow us to understand both the hardness of questions related to continuous time dynamical systems and the computational power of continuous time analog…

We respond to the criticism raised in the paper arXiv:1704.07831.

This paper reviews the Church-Turing Thesis (or rather, theses) with reference to their origin and application and considers some models of "hypercomputation", concentrating on perhaps the most straight-forward option: Zeno machines (Turing…

The Halting Problem is ill-conceived and ill-defined.

Despite the obvious utility of the concept, it has often been argued that time does not exist. I take the opposite perspective: let's imagine that time does exist, and the universe is described by a quantum state obeying ordinary…