Tuesday, 2 July 2019

quantum field theory - Nothing vs. empty space


This question quotes Hawking saying:



[...] you enter a world where conjuring something out of nothing is possible (at least, for a short while). That's because at this scale particles, such as protons, behave according to the laws of nature we call "quantum mechanics", and they really can appear at random, stick around for a while, and then vanish again to reappear somewhere else.



Nowever, is empty space really nothing? is there a distinction between non-existence and the "nothingness" of space?


Perhaps space is something, we just cannot grasp exactly what it is. Anyone can shed light on whether space is something and what exactly that "something" is.



Answer




is empty space really nothing?

The physicist's 'nothing' is an example of something to the philosopher for which 'nothing' is well, let this philosopher explain in a review of "A Universe from Nothing" by Lawrence Krauss:



empty space governed by quantum mechanics (or any other laws of physics, or even just the laws of physics by themselves) is not nothing, and not even an “example” of nothing (whatever an “example of nothing” means), but something. And it remains something rather than nothing even if it is a “good first approximation” to nothing (which is what Krauss presumably meant by “good first example”). When people ask how something could arise from nothing, they don’t mean “How could something arise from almost nothing?” They mean “How could something arise from nothing?” That is to say, from the absence of anything whatsoever -- including the absence of space (empty or otherwise), laws of physics, or anything else.



No comments:

Post a Comment

Understanding Stagnation point in pitot fluid

What is stagnation point in fluid mechanics. At the open end of the pitot tube the velocity of the fluid becomes zero.But that should result...