What shape would the Univers be if we could see all of it

  • Context: Graduate 
  • Thread starter Thread starter Worzel
  • Start date Start date
  • Tags Tags
    Shape
Click For Summary
SUMMARY

The discussion explores the potential shapes of the universe, comparing it to two-dimensional and three-dimensional models. It highlights the toroidal shape, akin to a doughnut, and suggests that the universe could also be spherical or even infinite. The analogy of a rubber ring and a balloon illustrates how a spaceship might navigate through different dimensions of the universe. Additionally, a detailed drawing exercise is provided to visualize the universe's structure, emphasizing the concept of voids and galaxy clusters.

PREREQUISITES
  • Understanding of basic geometric shapes, specifically toroidal and spherical forms.
  • Familiarity with dimensional concepts in physics, particularly in relation to space travel.
  • Knowledge of visual representation techniques, such as drawing and using a compass.
  • Basic comprehension of cosmology and the structure of the universe.
NEXT STEPS
  • Research the implications of a toroidal universe in cosmology.
  • Explore the concept of higher-dimensional spaces in theoretical physics.
  • Learn about the dodecahedral model of the universe and its significance.
  • Investigate the role of voids in the cosmic structure and galaxy formation.
USEFUL FOR

Astronomers, physicists, educators, and anyone interested in the theoretical shapes and structures of the universe.

Worzel
Messages
7
Reaction score
0
I was watching a program some months ago about the Universe and what shape it could be. In the program they used the Atari Asteroids game as an example.

As the spaceship starts to go off the right hand side of the screen it starts to appear on the left hand side. As the spaceship starts to go off the top of the screen it starts to appear at the bottom of the screen.

For the spaceship to do this, the left and right side of the screen must touch each other. like a map of the Earth on a sheet of paper. The same goes for the top and bottom of the screen.

This made the games Universe two dimensional. If you travel left, right, up or down you would return to the point you started from. This universe would be toroidal (doughnut shaped). However, I cannot see why it could not be spherical (globe shaped). If you fly north, south, east or west in a plane you will return to the point you started from. Both of these shapes could be elliptical (squashed) in one or both plains.

The programme then posed a question. What would the universe look like if it was three dimensional? Ie. Not only would you return to the same point if you traveled left, right, up or down but you would also return to the same point if you traveled backwards or forwards.

When you look at a banana under a microscope you would have difficulty in telling what shape it is. However, as we can look at the whole of a Banana we know what shape it is.

When it comes to the Universe, we can only see a very, very tiny amount of it and because of this we cannot say that it is shaped like an apple, a pair a doughnut or for that matter a bunch of grapes. It could even be infinite in size and have no shape to it at all.

Anyhow, the programme got me thinking and a thought crossed my mind. What shape would I get if I pulled up the edges of a doughnut and did the same thing pulling the edges down.

In my minds eye, I had turned the outside of the doughnut into a sphere but the middle of the sphere would still have a whole in it (shaped like an apple core).

The simplest way to explain what it looks like is to use a rubber ring, like the ones you can buy for a dog to play with www.valupets.com/pets/rubber-toys/large-rubber-ring-dog-toy/22362.html and a round balloon.

Blow up the balloon so that it has the same circumference as the rubber ring (7 inches) and then put the balloon into the middle of the ring so that the balloon has the ring running round the middle of it.

I do not think the universe is as uniform as this and the shape may very a lot but this shape simplifies what will happen when a spaceship travels through this universe.

A spaceship is sitting in space above and forward of the Earth, turns right and fires up the engines. It will be traveling in the first dimension. That means the spaceship is traveling round the circumferences of the rubber ring.

If the spaceship points itself upwards and fires up the engines, it will be traveling in the second dimension. That means the spaceship is traveling round the balloon.

If the spaceship just fires up the engines and moves forward, it will travel in the third dimension but this time it will be going round the thickness of the rubber ring.

Compared to the other two, this would be a much, much shorter journey and could be the reason why the universe is thought to be on the flat side.

Comments would be gratefully appreciated but can you please keep them simple enough for me to understand.

To see a cross section of the universe, like cutting an orange in half, follow the instructions below.

Using a pencil, draw a horizontal and vertical line across the middle of an A4 sheet of paper. Put a compass in the middle of the paper and draw a circle with a 50mm radius. For the top right and bottom left quadrants go over the pencil lines with a black pen and the other two with a red pen.

Draw a pencil line from the left edge of the top right quadrant to the left edge of the bottom left quadrant. Find the middle of the line and draw a circle that will touch the end of the top and bottom quadrant. Mark the line of this circle in back ink, where it is inside the first circle and red ink where it is outside the first circle. Now do the same for the other side.

You should now have a black shape that looks like an apple core and two red areas that are crescent shaped. Draw a circle, in black ink, round the whole lot, that just touches the outside edge of the two crescent shapes and then remove all the pencil lines.

The edge of the circle is the outer edge of the universe, beyond which there is nothing and the apple core shape is the inner edge of the universe, again beyond this there is nothing. The red area is the only area where galaxies exist.
 
Last edited:
Space news on Phys.org
It looks like a bubble bath, all the bubbles being empty voids, and only where the bubbles connect you find galaxy clusters, etc.
 
And some argue that the universe is shaped dodecahedral
 

Similar threads

  • · Replies 16 ·
Replies
16
Views
3K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 8 ·
Replies
8
Views
9K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 52 ·
2
Replies
52
Views
8K
  • · Replies 96 ·
4
Replies
96
Views
12K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 10 ·
Replies
10
Views
5K
  • · Replies 10 ·
Replies
10
Views
4K
  • · Replies 1 ·
Replies
1
Views
1K