Relativistic Effects on our Observations of the Universe

[Ralph Spencer]

While observing the Sun, which is 8 light-minutes 12 light-seconds away from us. We (by visible and invisible spectrum of the electromagnetic radiation) observe its state 8.20 minutes ago. Special relativity forbids any information to travel at speeds greater than that of light. This should apply to the information that a mass exists at a particular distance, which is mediated by gravitons. Thus, by all means, the information about Sun that we have is 8.2 minutes old.

If we apply this to Deneb, a star 1.4k light-years away from Earth, its state at a time 1.4k years will we see. Then to the M87 galaxy - 55 ± 1 Mly - its state at a time 55 ± 1M years ago.

How do we model the universe at present (for computations) when we have information that is older further the body away from us? More importantly, how can we compare two objects at different times?

 

[Chronos]

Correct! EM radiation emitted by all objects in the universe are time delayed due to the finite speed of light. The computation process is, as you surmised, complicated - and further complicated by redshift.

 

[Ralph Spencer]

The computation process is, as you surmised, complicated - and further complicated by redshift.

I would like to have a basic idea of the concept. What would be the error graph when approximate data is extrapolated to such large values?

Maybe I'm thinking far ahead of my current knowledge (which I would rate as beginner), however, if the newly created matter is not accounted in this model, by any chance could our mysterious dark matter be what is created but cannot be observed because of the time delay, which, I could expect to get answer to even in my thread about https://www.physicsforums.com/showthread.php?p=2854997" , which I could relate to motion of the spin-2 and massless gravitons in "certain" conditions.

 

[Janus]

I would like to have a basic idea of the concept. What would be the error graph when approximate data is extrapolated to such large values?

Maybe I'm thinking far ahead of my current knowledge (which I would rate as beginner), however, if the newly created matter is not accounted in this model, by any chance could our mysterious dark matter be what is created but cannot be observed because of the time delay, which, I could expect to get answer to even in my thread about https://www.physicsforums.com/showthread.php?p=2854997" , which I could relate to motion of the spin-2 and massless gravitons in "certain" conditions.

Exactly what "newly created matter" are you referring to?.

Even if we accepted the idea of such matter springing from nothing, we wouldn't see the effect it has on other objects any sooner than we would see it.

 

[sardar]

As a scientist, it is important to understand the concept of relativistic effects on our observations of the universe. The theory of special relativity, proposed by Albert Einstein, states that the speed of light is the maximum speed at which any information can travel. This means that any information we receive from distant objects in the universe is already outdated by the time it reaches us.

In the example given, we observe the Sun as it was 8.20 minutes ago, because that is how long it takes for light to travel from the Sun to Earth. Similarly, when we observe Deneb, a star 1.4k light-years away, we are seeing it as it was 1.4k years ago. This also applies to the M87 galaxy, which is 55 ± 1 million light-years away, meaning we are seeing it as it was 55 ± 1 million years ago.

This raises the question of how we can model the universe at present, when the information we have is already outdated. The answer lies in our understanding of the laws of physics and our ability to make predictions based on those laws. We can use mathematical equations and computational models to predict the current state of objects in the universe, even if the information we have is from the past.

In terms of comparing two objects at different times, we must take into account the speed at which information travels and the distance between the objects. This allows us to make accurate comparisons and understand the changes that have occurred over time.

In conclusion, while relativistic effects may complicate our observations of the universe, as scientists, we have the tools and knowledge to account for these effects and make accurate predictions and comparisons. It is through our understanding of the laws of physics and our ability to use mathematical models that we can continue to expand our knowledge and understanding of the universe.