How is the Universe Expanding?

[Alonzo.nieves]

Hello all. I'm quite new to this forum. I was wondering about the expanding or stretching universe. Can someone please tell me if my thoughts are correct and if not please correct me.

The expanding universe. A common definition of the universe is everything. But if the universe is expanding it has to be expanding into something. Expanding into a larger universe maybe? But I believe that a more accurate description of the universe is stretching. You can see the universe as a collection of galaxies a certain amount away from each other. A theory I have developed is that maybe the universe is just stationery. But as time passes the space between each galaxy and celestial bodies slowly move away, this shows the stretching of the galaxy. According to Einstein's theory of general relativity we have to think of space as a much more complex entity not just a vast amount of nothingness. Incorporating his theories of general relativity space should be capable of "bending" and "stretching".


If the space between celestial bodies are moving then what about the atoms, the building blocks of all matter. Maybe the spaces between them too are moving apart from each other. Or maybe its just the larger objects. Is the universe really powerful enough to rip the very fabric of everything we know into nothing? Does anyone know any recent research on this?

 

[Bandersnatch]

Hi Alonzo, welcome to PF.

The expanding universe. A common definition of the universe is everything. But if the universe is expanding it has to be expanding into something. Expanding into a larger universe maybe? But I believe that a more accurate description of the universe is stretching. You can see the universe as a collection of galaxies a certain amount away from each other. A theory I have developed is that maybe the universe is just stationery. But as time passes the space between each galaxy and celestial bodies slowly move away, this shows the stretching of the galaxy. According to Einstein's theory of general relativity we have to think of space as a much more complex entity not just a vast amount of nothingness. Incorporating his theories of general relativity space should be capable of "bending" and "stretching".

No, it doesn't have to expand into something else. What you describe as "stretching" is actually what the expansion is. You might not like the name, but that's how it's used in cosmology. The actual theories are expressed mathematically, and what anybody calls the results is just a matter of semantics.

If the space between celestial bodies are moving then what about the atoms, the building blocks of all matter. Maybe the spaces between them too are moving apart from each other. Or maybe its just the larger objects. Is the universe really powerful enough to rip the very fabric of everything we know into nothing? Does anyone know any recent research on this?

Expansion of space does not affect small scale structures(up to and including galaxies). They're held together too strongly by their gravity.

This type of questions would fit better in the cosmology section of the forum. There's a bunch of sticky threads in there that you might find interesting, inluding the FAQ. A forum search might net you a few interesting threads tackling the very same questions you asked.

 

[Alonzo.nieves]

Thank you for that. Next time I will post in the Cosomology section. By the way I'm quite new to this here, I just started High School.

 

[Naty1]

You can see the universe as a collection of galaxies a certain amount away from each other.

This sounds like the observable universe...the tiny part we can observe.

http://en.wikipedia.org/wiki/Observable_universe

A theory I have developed is that maybe the universe is just stationery. But as time passes the space between each galaxy and celestial bodies slowly move away, this shows the stretching of the galaxy.

How do you define 'stationary'.

Be careful about posting personal theories here. Not allowed. Much better to study generally accepted models first and then ask questions about those if there are parts you don't understand.

In the most popular cosmological model, the 'FRW lambda cdm cosmological model', distances over intergalactic distances expand over time...but the movement at increasingly large distances is not 'slow'.

overview here: http://en.wikipedia.org/wiki/Lambda-CDM_model

and as already noted, lots of prior discussions available in these forums...

 

[sardar]

I can tell you that your thoughts are on the right track, but there are still some misunderstandings that need to be corrected. First, it is important to understand that the universe is expanding in all directions, not just into a larger universe. This means that the space between all objects, including galaxies and atoms, is increasing. It is not just the larger objects that are moving apart, but everything is moving apart from everything else.

Secondly, the universe is not stretching like a rubber band, as your theory suggests. Instead, it is the space itself that is expanding. This means that the distance between objects is increasing, but the objects themselves are not physically stretching.

You are correct in incorporating Einstein's theory of general relativity, as it plays a crucial role in understanding the expansion of the universe. According to this theory, space can indeed bend and stretch, and this is what is happening as the universe expands.

As for the question about the universe being powerful enough to rip everything apart, the answer is no. The expansion of the universe is a slow and gradual process, and it is not tearing apart the fabric of everything we know. In fact, it is a natural and necessary part of the evolution of the universe.

There is ongoing research and study into the expansion of the universe, and there are still many unanswered questions. But we have a solid understanding of the basics of how the universe is expanding, thanks to scientific observations and theories like general relativity.

I hope this helps clarify some of your thoughts and questions about the expanding universe. Keep exploring and learning about this fascinating topic!