Plotting 180 Degrees Apart Galaxies in Spacetime Diagram

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In summary, The speaker is seeking help to draw a spacetime diagram of their galaxy and two other young galaxies at a 180 degree angle from the published HUDF. They are questioning how to approximate the angle on the diagram and where the observed galaxies should be placed in relation to each other and the speaker's own galaxy. They also mention difficulty in including concepts such as accelerated expansion and the inflationary era in the diagram.
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thorium
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I think this will help me understand things better, please help.
I would like to draw a spacetime diagram of our galaxy. But I would also like to plot on the diagram two young galaxies, say 400 million years old ABB (such as those seen in the HUDF), only that they must be 180 degrees apart as seen from our galaxy. As if Hubble were now pointed 180 degrees away from the published HUDF and took another picture.

Now its easy enough to draw our past light cone. And both galaxies should lie within it, close to the null asymptotes. But how do I approximate the 180 degrees in the diagram?

Also, if I now draw the light cones (future and past)of the observed galaxies themselves, should they include one another? in their future? In their past?

I tried to do it myself, but got a headacke.
Moreover, how sould such things as the accelerated expansion and possibly the inflationary era look in the diagram?
 
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Can't be done, can it?
 

1. How do you plot galaxies that are 180 degrees apart in a spacetime diagram?

In order to plot galaxies that are 180 degrees apart in a spacetime diagram, you will need to use a coordinate system that accounts for both space and time. This can be done using a 3+1 dimensional spacetime diagram, where three dimensions represent space and one dimension represents time. This allows for the accurate plotting of galaxies that are 180 degrees apart in both space and time.

2. What is the significance of plotting galaxies that are 180 degrees apart in a spacetime diagram?

Plotting galaxies that are 180 degrees apart in a spacetime diagram allows us to understand the relationship between these galaxies in both space and time. It can also provide insights into the evolution of these galaxies and how they interact with each other over vast distances.

3. Can galaxies that are 180 degrees apart in a spacetime diagram ever interact with each other?

Yes, galaxies that are 180 degrees apart in a spacetime diagram can interact with each other. This is because while they may be located at opposite ends in space, they can still experience gravitational pull from each other. Additionally, their trajectories may intersect in the future, allowing for potential interactions.

4. How is time represented in a spacetime diagram?

In a spacetime diagram, time is represented as the fourth dimension. This is typically denoted by the vertical axis, while the three spatial dimensions are represented by the horizontal axes. This allows for a visual representation of how time and space are interconnected and how objects move through both dimensions.

5. What other types of objects can be plotted on a spacetime diagram?

Spacetime diagrams can be used to plot a variety of objects, including particles, stars, galaxies, and even entire universes. The key is to use a coordinate system that accounts for both space and time, allowing for the accurate representation of the object's position and movement in both dimensions.

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