Is the Universe Infinite or Finite?

[Calimero]

I agree, simpler the better. Now it is just matter of coming up with theory that is in good agreement with the real world. If you could do that I am sure that you wouldn't be ridiculed, but praised.

 

[dgtech]

Such theory will only be granted recognition if it has practical implications, that would be something theoretical mainstream cosmology would not be able to match. For example, if a theory results in something the mainstream considers impossible to achieve, like FTL travel or singularity generator or something. The mainstream is overprotective when it comes to its integrity, and more logical theories will not be accepted for being more logical. At least my experience has taught me so.

 

[cristo]

How exactly do you know those effects are due to dark energy? You should learn the difference between hypothetical and real life science, instead of trying to convince me ;)

When most people use the term "dark energy", what they really mean is "the thing that explains why the universe is accelerating at the present time". Dark energy is just easier to say, but the jury is still out on whether this is some matter/energy content of the universe, or whether it's some modification of gravity on large scales.

I don't really agree with the idea the whole universe was once a singularity, but it is plausible if the observable universe was once the size of a theoretical singularity, or a Planck length.

Good, because that's not what the standard model says. The singularity is just an artefact of turning the clock back on the cosmological model too far, and is simply regarded as an indication that the model breaks down at some point.

The mainstream is overprotective when it comes to its integrity, and more logical theories will not be accepted for being more logical. At least my experience has taught me so.

Of course a theory is not accepted for being "more logical". The grounds for a theory being accepted into the mainstream are observations: if you have a theory which makes a prediction which is then confirmed by observations to fit closer than the current mainstream theory, then people will listen. Otherwise, the talk about

 

[dgtech]

Of course, crating a more logical theory includes adequately addressing all observations and questions, including those that the current mainstream refuses to even go into. Otherwise it won't be more logical, at least in my concepts.

 

[StandardsGuy]

Good, because that's not what the standard model says. The singularity is just an artefact of turning the clock back on the cosmological model too far, and is simply regarded as an indication that the model breaks down at some point.

I've never heard the term standard model used for the BBT. How does it start then, in your opinion? What do you base the "standard model " on?

 

[bapowell]

Of course, crating a more logical theory includes adequately addressing all observations and questions, including those that the current mainstream refuses to even go into. Otherwise it won't be more logical, at least in my concepts.

Which observations and questions do you feel the current mainstream refuses to go into?

 

[dgtech]

Like pre big bang conditions and factors that "caused" it, like attributing every illogical observation to some phantom force or energy instead of looking for plausible and simple enough to work solutions.. etc...

Just look at your answer in the "What force caused the Big Bang? The force that acted upon the singularity to expand" thread you just posted

 

[cristo]

I've never heard the term standard model used for the BBT.

It's quite a common term. See, e.g., http://cosmology.berkeley.edu/Education/CosmologyEssays/The_Standard_Cosmology.html

How does it start then, in your opinion?

In my opinion, a theory of quantum gravity is needed to tell us that.

What do you base the "standard model " on?

It's based on agreement with observation.

 

[bapowell]

Like pre big bang conditions and factors that "caused" it, like attributing every illogical observation to some phantom force or energy instead of looking for plausible and simple enough to work solutions.. etc...

Well, cosmology is unequipped to address what "caused" it. We need a UV complete theory of gravity in order to do that. Of course we'd love to have such a thing, but until that day comes, we have to be content to push our current theories to the limits of their applicability. Cosmology has been very successful in describing the earliest moments of the universe, in the regime in which general relativity can be meaningfully applied.

As for 'illogical observations', I'm not sure I follow you. How can you ascribe logic to an observation? Do you not consider the proposal of particulate dark matter (weakly interacting particles that are well accommodated as thermal relics in standard cosmology and arise naturally in modest extensions of the standard model of particle physics) to be plausible and simple?

As for dark energy, I can't scarcely think of something more simple than sticking a cosmological constant into Einstein's Equations. If you accept that the universe is undergoing accelerated expansion (ie you accept the observations to be true), then you are faced with really two options: change the gravitational theory or change the energy content of the universe. Both programs have been vigorously explored and continue to be stringently tested. I'm interested in hearing how you think these programs could be improved, or, if you think a different explanation is called for, what that might be.