I Is there any mechanism possible for the Big Brake?

[Trollfaz]

https://arxiv.org/abs/0705.1688
https://ui.adsabs.harvard.edu/abs/2014IJMPD..2350054P/abstract
https://www.scientificamerican.com/article/time-s-end-will-be-the-end-of-endings/
According to these references they suggest that dark energy can suddenly change sign and causing the universe expansion to stop and turn static immediately, resulting in extreme(infinite) deceleration.
Is this just a speculation if how dark energy evolves in the future. As far as I know we have no idea how dark energy behaves in the far future that's why scientist come up with a lot of theories.

 

[PeterDonis]

According to these references they suggest that dark energy can suddenly change sign

I don't think this is a good description. I realize it appears in the Scientific American article, but that's a pop science article and should not be taken as an accurate description of the actual physics.

The first paper you reference describes the "big brake" equation of state as $p = A / \rho$, which is nothing at all like dark energy (dark energy is $p = - \rho$). It is also nothing like matter or radiation, and in fact is nothing like anything we have ever observed. The paper makes no claim whatever about what would bring about such an equation of state, or whether it is even physically reasonable (my answer to that would be "no").

Is this just a speculation if how dark energy evolves in the future.

It's certainly a speculation, and one without any foundation in what we currently know, as far as I can see; it's just an abstract investigation into the implications of a particular mathematical model. But, as above, it has nothing to do with dark energy.

As far as I know we have no idea how dark energy behaves in the far future

If you want to discard everything we currently know about physics and say that anything goes, then of course we have no idea about how anything behaves in the far future. But that does not strike me as a fruitful way to proceed.

that's why scientist come up with a lot of theories.

Scientists come up with a lot of speculations because (a) it's fun, and (b) it helps to generate more published papers. The vast majority of these speculations never result in anything relevant to our actual universe.

Note also that the point of the first paper is to show that quantum effects prevent the classical "big brake" scenario from actually happening.

 

[Trollfaz]

I don't think this is a good description. I realize it appears in the Scientific American article,

Yes the Scientific American article does in fact make a lot of unverifiable claims like the big lurch in the picture which has no supporting reference as well as the claim that phantom energy freezes everything in place.

 

[James William Hall]

An interesting aside to the question: what if space did stop expanding suddenly? What would be the effect on visible objects like galaxies and black holes?

 

[Ibix]

An interesting aside to the question: what if space did stop expanding suddenly? What would be the effect on visible objects like galaxies and black holes?

You'd have to provide a mechanism by which it could "suddenly stop". Since we aren't aware of one, we can't really answer the question.

Honestly, in this context "space expanding" is not the best description of what's going on, although there are good reasons why people use it. The simplest way to put it is that galaxies move apart for the same reason a pool ball keeps rolling: inertia. It's complicated by the curvature of spacetime, which is where the "expanding space" explanation comes in, but at the root of it if you want to stop "space expanding" you just need to stop all the galaxies. We don't know a mechanism that can do that - hence my first paragraph.