# Ultimate gravity

#### Deicider

"ultimate" gravity

Am not a scientist or physicist or even good at those,i have limited knowledge.
I've been wondering about gravity and with my humble knowledge am trying to making sense of it.

"Singularity" was the ultimate massive black hole,it exploded/expanded giving space and time.
It seems that unlike other forces gravity is the most fundamental,since it moves around stars and galaxies.
The most basic property of matter: attraction.Without it i dont think anything would form.

What i wanna say is that it seems to me that gravity is the force that "creates" time and space.

If universe was crushed into a singularity that only means gravity "Pulled" space and time Inside the singularity,why? because it might be space and time itself.

We're assuming bang and crunch are caused by gravity(as far as i know).
If something like that can suppress time and space into a tiny bit and then expand space then its pretty obvious that they are directly associated.

Not taking account dark energy and matter which takes up 90%+ of the universe,other dimensions etc.
So am making a huge amateur assumptions.
Does this makes any sense?

Edit: just noticed it went to the wrong subforum,i think this goes somewhere in cosmology or smth.

#### marcus

Gold Member
Dearly Missed
Re: "ultimate" gravity

"Singularity" is a model-dependent idea. A singularity is a failure of some particular manmade theory.

So whether or not you have a singularity depends on which manmade theory you are using---it is a mathematical breakdown where the formulas start to give infinities or meaningless unreliable numbers.

A singularity is generally taken by scientists as a sign that the theory doesn't cover that case and has been pushed beyond its limits, so they start working on how to FIX IT. How to modify the theory so that the singularity breakdown will not occur.

This has happened repeatedly in different branches of physics.

In the case of cosmology the theory that fails is the 1915 version of General Relativity. When you use it to describe the early universe it breaks at the start of expansion. But it's a fine old classic theory and could do with some improvement.

So people have been hard at work developing cosmological models that don't develop a singularity, or glitch. Classic Einstein GR is almost 100 years old and it is widely recognized that it needs to be modified so as not to break down in extreme conditions (extreme density especially).

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#### marcus

Gold Member
Dearly Missed
Re: "ultimate" gravity

Here's a discussion thread we had in Cosmology subforum called "Before Big Bang"

It discussed various models physicists are working on that deal with what process or conditions could have led to the big bang and taken part at the onset of expansion.

Somewhere in that discussion thread somebody gave links to a one-hour BBC program on that topic. The BBC program was titled "What happened before the big bang"

The program covered a range of half dozen ideas some of which I think are too vague and fancy. My taste favors the simplest model that gets the job done so to speak. But people's assessments differ widely, so I will copy all 6 links. Each link is to a 10 minute segment.
So you get 60 minutes in all.

YouTube - BBC Horizon 2010: 1/6 What Happened Before the Big Bang
YouTube - BBC Horizon 2010: 2/6 What Happened Before the Big Bang
YouTube - BBC Horizon 2010: 3/6 What Happened Before the Big Bang
YouTube - BBC Horizon 2010: 4/6 What Happened Before the Big Bang
YouTube - BBC Horizon 2010: 5/6 What Happened Before the Big Bang
YouTube - BBC Horizon 2010: 6/6 What Happened Before the Big Bang

#### Kevin_Axion

Re: "ultimate" gravity

Quantum Electrodynamics experiences singularities since the force of electromagnetism is dependent on distance therefore when your distance approaches zero your force diverges. Also Gravitational Singularities/Black Holes are an example of a singularity but can be solved in the context of Superstring Theory by using Fuzzballs: http://en.wikipedia.org/wiki/Fuzzball_(string_theory [Broken]). By the way I watched the documentary marcus posted and it's very informative, I loved the fact that was situated at the Perimeter Institute.

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