Apr 7, 2017 11:30 PM
The Quest for Unity Is Not Something Physics Is Cut Out to Do
http://m.nautil.us/blog/the-quest-for-un...-out-to-do
EXCERPT: [...] Any theory that attempts to determine unambiguously the initial conditions of the universe and, with them, the values of the fundamental constants, is doing something physics is not cut out to do. Are we stuck then, having to accept the values of these constants for what they are? Within the current framework, yes. Attempts around this issue, even if inspiring, will amount to not much more than epicycles.
But all is not lost. The search for a simple all-encompassing theory has eclipsed a more enduring insight about the nature of physics. Physics is the building of an ever-changing, self-correcting description of natural phenomena. In its practice, it sets aside metaphysical expectations about the nature of reality, which have more to do with how we search for meaning as humans than with how nature actually works. In other words, physics is an expression of intellectual humility. We learn to live with ignorance and, in return, gain the ability to make progress incrementally....
Can Many-Worlds Theory Rescue Us From Boltzmann Brains?
http://m.nautil.us/blog/can-many_worlds-...ann-brains
EXCERPT: [...] But it turns out that, since the universe is expanding, these apparent fluctuations might not be coming from the vacuum. Instead, as the universe expands, the edge of the observable universe causes thermal fluctuations to appear, much like the event horizon of a black hole gives rise to Hawking radiation. This gives the appearance of vacuum fluctuations, from our point of view. The true vacuum of space and time isn’t fluctuating, so it cannot create a Boltzmann brain. The idea, from Caltech physicist Kimberly Boddy, and colleagues, is somewhat speculative, and it has an interesting catch. The argument that the true vacuum of the universe is stationary relies on a version of quantum theory known as the many-worlds formulation....
http://m.nautil.us/blog/the-quest-for-un...-out-to-do
EXCERPT: [...] Any theory that attempts to determine unambiguously the initial conditions of the universe and, with them, the values of the fundamental constants, is doing something physics is not cut out to do. Are we stuck then, having to accept the values of these constants for what they are? Within the current framework, yes. Attempts around this issue, even if inspiring, will amount to not much more than epicycles.
But all is not lost. The search for a simple all-encompassing theory has eclipsed a more enduring insight about the nature of physics. Physics is the building of an ever-changing, self-correcting description of natural phenomena. In its practice, it sets aside metaphysical expectations about the nature of reality, which have more to do with how we search for meaning as humans than with how nature actually works. In other words, physics is an expression of intellectual humility. We learn to live with ignorance and, in return, gain the ability to make progress incrementally....
Can Many-Worlds Theory Rescue Us From Boltzmann Brains?
http://m.nautil.us/blog/can-many_worlds-...ann-brains
EXCERPT: [...] But it turns out that, since the universe is expanding, these apparent fluctuations might not be coming from the vacuum. Instead, as the universe expands, the edge of the observable universe causes thermal fluctuations to appear, much like the event horizon of a black hole gives rise to Hawking radiation. This gives the appearance of vacuum fluctuations, from our point of view. The true vacuum of space and time isn’t fluctuating, so it cannot create a Boltzmann brain. The idea, from Caltech physicist Kimberly Boddy, and colleagues, is somewhat speculative, and it has an interesting catch. The argument that the true vacuum of the universe is stationary relies on a version of quantum theory known as the many-worlds formulation....