The Big Bangy Field Equation

[sethoflagos]

Three questions have recently been bothering me.

 

If the universe originated (as I read on a lavatory wall somewhere) as a field of superimposed probabilities of all possible futures:

 

1) Would that field be necessarily bounded in any dimension before any 'actual' future began to unfold?

 

2) Is there any damning reason why the fundamental constants of our universe could not be quantum variables, initially indeterminate?

 

3) Would combinations of fundamental constants that led to eternally expanding, species diverse universes have more 'quantum votes' (ie a higher probability of manifesting themselves) due to their greater number of permutations than those combinations that led to finite universes supporting a low diversity of elemental species?

 

Many thanks in advance for your considered points of view.

[Daecon]

What does "field of superimposed probabilities" actually mean? To the untrained ear, it sounds like word salad.

[MigL]

The Big Bang says nothing about T=0.

It only describes what happens once expansion begins.

 

I don't know what your first statement means, maybe you could re-frame it ?

 

1 I would think dimensions emerged with expansion, the three spatial dimensions and the time dimension may have become 'macro' but there may yet be compacted dimensions at Planck scales. In all cases we can say nothing about 'external' or embedding dimensions, so the simplest assumption is there aren't any.

 

2 You could have different choices, like a pencil balanced on its tip, to fall over in any direction. Once you break that rotational symmetry by pushing the pencil over on its side, it now has a fixed direction, symmetry has been broken and you only have a single choice. So yes, a symmetry break could 'fix' what was previously variable.

 

3 I have no idea why an outcome favoring complexity would be more preferable than one with limited complexity.

( and preferable to whom ? )

Edited March 10, 2017 by MigL

[Itoero]

If the universe originated (as I read on a lavatory wall somewhere) as a field of superimposed probabilities of all possible futures

How can the universe originate as a field of probabilities? Then what determined are current 'future'?

[sethoflagos]

The Big Bang says nothing about T=0.

It only describes what happens once expansion begins.

 

I don't know what your first statement means, maybe you could re-frame it ?

 

 

Difficult to rephrase it without presupposing part of the answer. As I picture it, it's a Schrödinger equation describing the time evolution of the universe (or all possible universes courtesy of the superposition principle of quantum mechanics) in some kind of primordial Hilbert space.

 

 

 

3 I have no idea why an outcome favoring complexity would be more preferable than one with limited complexity.

( and preferable to whom ? )

 

Don't know where 'preferable' came from, Your invention not mine. The 2nd Law of Thermodynamics favours such outcomes. I guess I'm looking for some parallel between the 2nd Law and the time evolution of superimposed quantum states. They are both essentially statistical in behaviour after all,

[mantraphilter]

I equate your field of super imposed probabilities to my field of infinite possibilities, and my infinite invariable to the singularity that set everything in motion. I represent the infinite invariable as a Y with all the possibilities extending away from the Y. The Y is the single event in time that was caused by all the other events. as to what those events were, I guess you would have had to been close to middle of the Y to have witnessed them.

[StringJunky]

 

The Big Bang says nothing about T=0.

It only describes what happens once expansion begins.

 

I don't know what your first statement means, maybe you could re-frame it ?

 

GR falls apart as you approach zero because, IIRC, infinities starting popping up, so a new theory is needed that involves QT, which doesn't exist yet.

Edited March 10, 2017 by StringJunky

[sethoflagos]

GR falls apart as you approach zero, so a new theory is needed that involves QT, which doesn't exist yet.

 

We're getting too hung up on t=0 here.

 

Question 1) is really a general question about whether the quantum fields for a finite system at any particular instant extend throughout spacetime (even if the precise future geometry of spacetime were somewhat indeterminate).

[Country Boy]

Are we now considering a "lavatory wall" as a primary source of physics knowledge?

 

Will there be a thread on that fellow from Nantucket?