Question When we look back in time using Hubble or JWST?

[J@i]

When we look back in time using Hubble or JWST? Is it possible that we are seeing the same current galaxies in making including our galaxy Milkyway?

Is it possible that many galaxies that we see far away in time are nothing but random images of current galaxies at different stages of its birth and at points in space due to expansion.

Are we by any chance recounting the same galaxies (a same entity but different poses in its lifecycle) when we try to measure the visible mass of the Universe?

 

[SIDexplorer]

No, those are real galaxies whose existence is questionable but the light very much tells us that they did exist.

Our own galaxy is right here, it can't leave a hologram of itself for 4+ billion logjt years.

There's no chance that we're recounting or counting our own galaxy, that which is right here.

All those galaxies captured by Hubble amd Webb are but holograms of those galaxies, the way they once used to be.

Birth of those galaxies was way back than when it developed into a full galaxy, we've already missed their birth time the light of those times has crossed us long ago, only civilizations way more distant than 4+ billion ly, in a specific direction could witness their birth, if at all.

Light of their birth times has surpassed us, and any other civilization, and galaxies currently being formed elsewhere may one day be captured by our future generations.

 

[Catastrophe]

When we look back in time using Hubble or JWST?

Does anyone understand the question (post #1)?
If so, please explain it to me.

Cat

 

[J@i]

When we look back in time using Hubble or JWST?

Does anyone understand the question (post #1)?
If so, please explain it to me.

Cat

My post#1 question is:- All those ancient galaxies that we see today when we look back into time, is it possible that we are seeing the early holograms at different stages of birth of present day galaxies?

 

[Catastrophe]

I understand that better. Thanks

is it possible that we are seeing the early holograms at different stages of birth of present day galaxies?

No. I would say definitely not. To see yourself, you need some kind of mirror.
I just think the observable universe is limited only by our powers to observe. It has already been stretched enormously from naked eye to JWST.

Cat

 

[Willi]

When we look back in time, we can see some of the most distant and oldest galaxies that have ever been observed. These galaxies are so far away that their light has taken billions of years to reach us. By looking at these galaxies, we can learn about the early Universe and how it has evolved over time.

The Hubble Space Telescope and the James Webb Space Telescope are two of the most powerful telescopes that have ever been built. These telescopes can see further into the Universe than any other telescope, and they have been used to discover some of the most distant and oldest galaxies.

The Hubble Space Telescope was launched in 1990 and it has been used to observe the Universe for over 25 years. The James Webb Space Telescope is scheduled to launch in 2021 and it will be even more powerful than Hubble.

These two telescopes have been used to study the most distant galaxies in the Universe. In 2016, astronomers used Hubble to study a galaxy that is 13.4 billion lightyears away from Earth. This galaxy is so far away that its light has taken over 13 billion years to reach us. This means that we are seeing this galaxy as it was over 13 billion years ago.

In 2018, astronomers used the James Webb Space Telescope to study a galaxy that is even more distant than the one observed by Hubble. This galaxy is so far away that its light has taken over 13.5 billion years to reach us.

This means that we are seeing this galaxy as it was over 13.5 billion years ago. These observations are important because they allow us to study the early Universe. By looking at these distant galaxies, we can learn about how the Universe has evolved over time.

 

[Catastrophe]

Willi, welcome to the forum, and thank you for summarising what is known on this subject.

Cat

 

[JBUMAerospace]

Hi all! I joined and would like to follow this thread with a Q that has been with me since I heard we can look back towards the time of the Big Bang (one theory of the birth of everything as we know it).
Question: How can we see the early birth of the Universe that occurred 13.5+ Billion years ago IF we are that far away when observing? Did Earth, our solar system, our galaxy all originate from the Big Bang so long ago? Are we not observing the remnants of the Big Bang 13.5 Billion years later?

 

[Catastrophe]

Hi JBUMA,Welcome to the forum. Just forget about the BB for a moment.

We see by light. No problem for us during the daytime, as there is plenty of light. At night, away from city lights, we can see the stars. Forget the Moon also, for a moment. We do not get much light from the stars, because they are far away. So, to see them better, we use telescopes. The important thing about a telescope, is the diameter of the front lens, or rather, its area. The bigger this area, the more light it collects compared to our eyes. The more light, the better we see, and the more detail we see. Just think of looking through a telescope or binocular during the days.

Now back to the stars, or, rather, the nearest star, the Sun. We can measure its distance away using familiar units, like miles - 92.96 million. Just as a matter of interest, it takes light (at 186,000 miles per second) 8.317 minutes to reach us. Instead of saying that the Sun is 92,960,000 miles away, we can say that it is 8.317 light minutes away. A light minute is the distance travelled by light in one minute. A light minute is a distance, not a time.

By saying that it takes 8.317 minutes for the light to travel from the Sun, it means that we are seeing what happened on the Sun, maybe a flare, about minutes ago. We cannot magic ourselves to the Sun and change anything. The light left the Sun about 8.3 minutes ago, and we see the Sun as it was then - in the past. Or, rather, in the Sun's past. We see the Sun's past, in our present.

Now, come back to the stars. The nearest stars are about 23,500,000.000.000 miles but, instead of using these and much larger numbers, we find it convenient to measure these distances in light years (the distance light travels in a year). 4 is an easier number to handle than 2.351 x 10^13 or 2.351 x 10,000,000,000,000.

But there is another consequence of using light years as a measurement of distance. In one sense, we are looking into the past - the star's past as seen in our time. If an alien flashed a very bright light at us from 4 light years away, we would see his 4 year old signal arriving in our "now". We cannot, in any way, stop the alien flashing the light. That happened 4 years ago, but we only see it now, because it took light that long to travel.

I will come back on the BB shortly.

Cat

 

[Catastrophe]

Now let's get to the BB. The big bang (or BB) is a difficult term to understand, because the nearer we get to this big start (call it t = 0, or the beginning of it all) the less able is science to see what is going on. But keeping things simple (but not exactly as they were) we will just call the BB the time when things got going.

Your question is

Question: How can we see the early birth of the Universe that occurred 13.5+ Billion years ago IF we are that far away when observing? Did Earth, our solar system, our galaxy all originate from the Big Bang so long ago? Are we not observing the remnants of the Big Bang 13.5 Billion years later?

1. How can we see the early birth of the Universe that occurred 13.5+ Billion years ago IF we are that far away when observing?

There are things that stop us seeing right back to t = 0, because the state of the universe very early on did not allow light to pass through it. But that is not really what you want to know, is it? If I can rephrase you question (may I please?):

How can we see back to earliest times IF we are that far away when observing?

If we have large enough telescopes, especially if we mount them in space, we can see dimmer and dimmer stars from further and further away. As we saw above, larger telescopes allow us to collect more light, so we can see dimmer stars. Of course, if there are brighter objects back there, we will see them sooner.

We are that far away when observing, and we can see way back, but only if we have the right equipment. Primitive man could only see so far back because, like us, he had small diameter eyes. Maybe he could have seen the Andromeda Galaxy at 2.537 million light years, but that is only a tiny start compared to 13.5+ billion light years.

Of course, we cannot interact with anything long ago. If we see an alien 1 light year away, about to fire a weapon at Earth, there is no way we could stop him. He will already have fired it a year ago.

2. Did Earth, our solar system, our galaxy all originate from the Big Bang so long ago?
No, our Solar System came along much later - 4.571 billion years ago. Of course, we cannot see that now. We are too close. Theoretical aliens, say, around 4.571 billion light years away, could be watching it "now" in our present time. They cannot interfere with it because, for us, it already happened long, long ago.

3. Are we not observing the remnants of the Big Bang 13.5 Billion years later? Yes and no. We now are getting telescopes which can enable us to see nearly that far back. So, yes, we can see the remnants in the Cosmic microwave background - Wikipedia
https://en.wikipedia.org › wiki › Cosmic_microwave_b...

In Big Bang cosmology the cosmic microwave background (CMB, CMBR) is electromagnetic radiation that is a remnant from an early stage of the universe, also known ...

I hope that has helped. If you have any questions, please ask away.

Cat

 

[JBUMAerospace]

Thank you Cat for your cogent reply. Perhaps I did not state my conundrum clearly. I know that distance measured by the JWST and Hubble and any other telescope is based on the cosmological red shift meaning the further an image is in the infra-red part of the light spectrum the further away it is due to the expanding universe. To quote from the Hindu Newspaper (https://www.thehindu.com/sci-tech/s...-galaxies-in-the-universe/article65653281.ece):
"Our galaxy, the Milky Way, spans 100,000+ light-years. And the beautiful newborn stars seen in JWST’s Carina Nebula image are 7,500 light-years away. In other words, this nebula as pictured is from a time roughly 2,000 years earlier than when the first ever writing is thought to have been invented in ancient Mesopotamia. So we will be able to see light from 13.7 billion years ago. What’s about to hurt your brain, however, is that those galaxies are not 13.7 billion light-years away. The actual distance to those galaxies today would be ~46 billion light-years."
So I posit that we are not looking at the state of the Universe as it existed 200 million years after the Big Bang but perhaps how it looked 32.5 Billion light years AFTER the Big Bang, assuming of course that we did originate from a BB.

 

[Catastrophe]

If one poses as a beginner, then one might expect some helpful person to spend their time trying to help. I give my time freely to try to help those who come here in that genuine capacity.

Hi all! I joined and would like to follow this thread with a Q that has been with me since I heard we can look back towards the time of the Big Bang (one theory of the birth of everything as we know it).
Question: How can we see the early birth of the Universe that occurred 13.5+ Billion years ago IF we are that far away when observing? Did Earth, our solar system, our galaxy all originate from the Big Bang so long ago? Are we not observing the remnants of the Big Bang 13.5 Billion years later?

Person having ordinary skill in the art - Wikipedia

I do not believe that anyone in need of my help is able to quote this excellent link:

(https://www.thehindu.com/sci-tech/s...-galaxies-in-the-universe/article65653281.ece):

 

[Unclear Engineer]

Going back to reply #6, there is a problem with the statement:

In 2018, astronomers used the James Webb Space Telescope to study a galaxy that is even more distant than the one observed by Hubble.

The Webb telescope was not available for use until the summer of 2022.

 

[Unclear Engineer]

Going back to the OP, the question was really more about might we be somehow seeing the same galaxies more than once when we look out into space.

For that to happen, there would need to be some sort of reflecting surfaces that, like a "fun house" full of mirrors, made multiple images by reflecting reflections. Or, space would need to curve back on itself such that we were looking around it multiple times.

There is no evidence for either scenario. Attempts to find curvature in space seem to show that it is not curved. And we have no indication of reflecting surfaces.

 

[J@i]

Going back to the OP, the question was really more about might we be somehow seeing the same galaxies more than once when we look out into space.

For that to happen, there would need to be some sort of reflecting surfaces that, like a "fun house" full of mirrors, made multiple images by reflecting reflections. Or, space would need to curve back on itself such that we were looking around it multiple times.

There is no evidence for either scenario. Attempts to find curvature in space seem to show that it is not curved. And we have no indication of reflecting surfaces.

While asking this question I was as well considering the movement of the galaxies while expansion is happening. Our visible universe has moved along with us (maybe the most of it) while others who were formed along with our Milkyway may have moved in other directions and today we are not able to see those.

But here since we have all (our visible universe) moved in the same direction due to expansion, wont it be possible that we are seeing our same stars and galaxies at different stages of it's evolution while we look back in time. While I do understand the ideas of losing the lights from infant stages of our galaxies if we consider only time as a factor but here both time as well as galaxies along with our visible universe are also moving in the same directions chased by our own lights (provided we have moved faster than our lights due to the faster expansion of space).

Any thoughts??

 

[IG2007]

There is no evidence for either scenario. Attempts to find curvature in space seem to show that it is not curved. And we have no indication of reflecting surfaces.

Just wanted to make a small point here - General Relativity posits that gravity is a result of the curvature of spacetime, and therefore spacetime is curved. But, you are correct that space is not that much curved to make us able to see ourselves.

But here since we have all (our visible universe) moved in the same direction due to expansion, wont it be possible that we are seeing our same stars and galaxies at different stages of it's evolution while we look back in time. While I do understand the ideas of losing the lights from infant stages of our galaxies if we consider only time as a factor but here both time as well as galaxies along with our visible universe are also moving in the same directions chased by our own lights (provided we have moved faster than our lights due to the faster expansion of space).

Any thoughts??

Although I am not sure if I completely understand the question, I will try to answer to my interpretation of the question.

If I remember correctly, (I would like someone to correct me if my memory has been corroded), the expansion of the Universe is intrinsic in nature. It's not like explosions of bombs or shock waves of earthquakes that spread from a single point - in this case, spacetime itself is stretching itself apart.

I know that sounds weird (because it is), but think of it in the following way: Suppose there are five particles that are equidistant from each other. Due to the expansion of the Universe, the five particles will move away from each at a constant rate (which we know as the Hubble Constant, which is not really a constant, as it changes with time). So well, the ratio of the distances between the particles will remain the same (this is the part that I am a little unsure about, I would like someone else to verify this), but they will get farther and farther away from each other, and the speed of their moving apart will accelerate.

I hope this satisfies your question, you can google up the stuff that I am a bit unsure about and correct me if I'm wrong.

 

[Catastrophe]

When we look back in time using Hubble or JWST? Is it possible that we are seeing the same current galaxies in making including our galaxy Milkyway?

When we "look back in time", we do so only in the sense that we are receiving light from "long ago and far away". We cannot receive light from ourselves - at least we know of no "distant mirrors" which might have this effect. If we want to indulge in metaphysical fantasies, and postulate light running around the universe and back to us, remember that we have only about 5 billion years before the Sun goes giant. Nowhere near long enough.

Is it possible that many galaxies that we see far away in time are nothing but random images of current galaxies at different stages of its birth and at points in space due to expansion.

No. We only see light that has travelled directly to us. See above. We do not "see back in time" - only distant light from far away.

Are we by any chance recounting the same galaxies (a same entity but different poses in its lifecycle) when we try to measure the visible mass of the Universe?

No. We only see light that has travelled directly to us. See above. We do not "see back in time" - only distant light from far away. This light comes from fixed distances from us (light years) and light from one location comes to us as photons in a sequence. Light from one location arrives in strict order of departure. It does leap around and arrive in a muddled order.

There is one special case to consider. gravitationallensing.pdf (fnal.gov)
This does not alter any of my answers in the way you mean the questions.

Cat

 

[Helio]

I know that sounds weird (because it is), but think of it in the following way: Suppose there are five particles that are equidistant from each other. Due to the expansion of the Universe, the five particles will move away from each at a constant rate (which we know as the Hubble Constant, which is not really a constant, as it changes with time). So well, the ratio of the distances between the particles will remain the same (this is the part that I am a little unsure about, I would like someone else to verify this), but they will get farther and farther away from each other, and the speed of their moving apart will accelerate.

I would add that their relative motion would also depend on all influences upon them, not just expansion. This has been a matter of debate, admittedly.

If the rate of acceleration does apply locally, which is likely, and it continues to increase, which is the assumption, then it will overcome all else producing the Big Rip. [DE is considered to , somehow, have a constant density even with expansion, thus its net effect is getting stronger while the other things (eg mass) diminishes in density.]

iPhone

 

[Unclear Engineer]

The idea that DE keeps the same density as the universe expands is the same as saying that energy is constantly being created throughout space as space itself expands.

That is the type of postulating [I won't respect it as "theorizing"] that makes me doubt much of the Big Bang Theory, because it is a direct violation of the main underpinnings of the rest of the theory, as well as all of modern physics.

Except for Dark Energy, to total of energy + matter in the universe is conserved?! I think not. Serious theorists need to come up with a better idea. Otherwise, they will have opened the floodgates to all sorts of ideas that the known laws of physics were not just violated before the universe had expanded enough to hide behind the Heisenberg Uncertainty Principle, but that those laws are being violated continuously any time, anywhere in our visible universe. That would leave the whole science of cosmology in shambles.

 

[Helio]

DE is simply a label to help us to later explain the acceleration component of the expansion. It was never part of BBT until acc. was announced.

But it’s also associated with Einstein’s cosmological term he quickly added to his GR equation, which gives it a little more acceptability,

 

[Unclear Engineer]

Helio, I did not say that Dark Energy does not exist (although I am not convinced that it does).

What I objected to was the postulate that it somehow is increasing as space expands, so that there is more total energy in the universe every second, and that is the reason that the rate of the universe's expansion is increasing.

The idea that there is more dark energy in the universe because there is more space in the universe is directly in conflict with the principle of conservation of energy + mass in the universe.

Do you actually believe that principle is wrong?

If so, what other principles of physics are you willing to agree are being violated by what we observe? How about the speed of light being constant everywhere for all time? How about gravity being constant with time?

People seem to be unwilling to consider violations of even unprovable "laws" such as entropy could not decrease or that "information" cannot be lost or even hidden, no matter what happens inside a black hole. So then why are they willing to accept the hypothesis that energy is being created everywhere in space at an increasing rate all the time?

 

[billslugg]

I read up on Dark Energy and it says that it is a property of space, so if you create more space then you create more DE. Perhaps they are referring to the virtual particles that pop into and out of existance. This is "the energy of the vacuum" which is at the lowest level. Nothing is lower thus it cannot flow downward thus cannot do any work. Although it seems to be pushing the galaxies apart, so I don't know about that. I suppose this concept does not violate the law of conservation of energy since by adding space to our existing system the system is not closed. Conservation laws only apply to closed systems.

The proof that entropy always increases is based on the fact that heat and time only flow in one direction.

As for the preservation of information. I don't have a clue on that one. The only thing I have read that might help is that the define "information" differently than we do. I'll try to bone up on it some more.

 

[Unclear Engineer]

Bill,

So now you are saying the universe is not a closed system?

Since the universe includes "everything" by definition, it seems hard to understand how it cannot be closed and that there is energy pouring into it from somewhere else. But, it is either that or energy is being created within the universe from nothing?

It sounds like theorists are willing to throw out the fundamentals in order to describe the details.

And the result is chaos instead of insight.

 

[billslugg]

Yes, I suppose the universe is not a closed system as per the definitions used in the conservation laws.
For example, when we look at the farthest galaxies, at some point their rate of recession exceeds the speed of light so they disappear from our universe. Neither their light nor their gravity can be detected. They are no longer in the universe as far as we are concerned.
Remember, the universe was created from nothing and currently averages out to nothing. The positive energy of the mass in the universe is exactly balanced by the negative potential energy of gravitation.
Yes, it is very confusing but I will continue to strive to understand it.

 

[Unclear Engineer]

Bill, you are conflating the theoretical definition of the universe with the practical definition of the observable universe.