Jan 27, 2025 07:00 PM
(This post was last modified: Jan 27, 2025 07:21 PM by C C.)
https://iai.tv/articles/the-universe-is-..._auid=2020
INTRO: Humanity’s search for a theory of everything is one of the motivating forces behind the whole scientific endeavour. But is it possible for an observer within the universe to know everything about the universe? Philosopher of science JB Manchak here argues that we cannot know the structure of all of spacetime from any specific point within it – and this is the case even if we somehow collected all the possible perspectives, from every point in the universe. Due to arguments made available by Einstein’s general relativity, we cannot know the universe from within it.
EXCERPT: . . . Let's now consider a few common objections to the cosmic underdetermination result just presented. The argument presupposes the standard formulation of general relativity. But how can an observer within the universe be in position to know for sure that such a theory is true? She can't. But she also cannot rule out, with absolute certainty, any number of wild conspiracy theories concerning the universe. As noted by the philosopher Bertrand Russell: "There is no logical impossibility in the hypothesis that the world sprang into existence five minutes ago, exactly as it then was, with a population that 'remembered' a wholly unreal past''.
Russell goes on to emphasize that such skeptical 'theories' of spacetime are entirely uninteresting from a scientific point of view. In contrast, the argument for cosmic underdetermination sketched above is of some interest precisely because it proceeds within the context of our best large-scale physical theory: general relativity. It is curious that even within the strict confines of such a theory, no amount of empirical observation can determine the structure of the universe. Moreover, the result seems to hold within the context of any spacetime theory whose models do not have God points (e.g. any future theory of quantum gravity). The predicament is not unique to general relativity... (MORE - missing details)
INTRO: Humanity’s search for a theory of everything is one of the motivating forces behind the whole scientific endeavour. But is it possible for an observer within the universe to know everything about the universe? Philosopher of science JB Manchak here argues that we cannot know the structure of all of spacetime from any specific point within it – and this is the case even if we somehow collected all the possible perspectives, from every point in the universe. Due to arguments made available by Einstein’s general relativity, we cannot know the universe from within it.
EXCERPT: . . . Let's now consider a few common objections to the cosmic underdetermination result just presented. The argument presupposes the standard formulation of general relativity. But how can an observer within the universe be in position to know for sure that such a theory is true? She can't. But she also cannot rule out, with absolute certainty, any number of wild conspiracy theories concerning the universe. As noted by the philosopher Bertrand Russell: "There is no logical impossibility in the hypothesis that the world sprang into existence five minutes ago, exactly as it then was, with a population that 'remembered' a wholly unreal past''.
Russell goes on to emphasize that such skeptical 'theories' of spacetime are entirely uninteresting from a scientific point of view. In contrast, the argument for cosmic underdetermination sketched above is of some interest precisely because it proceeds within the context of our best large-scale physical theory: general relativity. It is curious that even within the strict confines of such a theory, no amount of empirical observation can determine the structure of the universe. Moreover, the result seems to hold within the context of any spacetime theory whose models do not have God points (e.g. any future theory of quantum gravity). The predicament is not unique to general relativity... (MORE - missing details)