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blueasian0682 t1_jb7ve9a wrote

For those curious but don't want to read,

First picture: day 0 (3.2 billion light years from earth)

Second picture: 320 days from the first pic.

Third picture: 1000 days from the first pic.

How do they know this? A supernovae clearly seen from the first pic can be seen in the other two images with the same positions but fading away in brightness.

Why are they different timelines? Gravitational lensing that not only bends light but also space time.

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moonsoundsonsnow t1_jb8glzi wrote

what I find amazing is that it's been 3.2 billion years since the supernova event, yet we just happen to be paying attention to a particular 3 yr period. quite the co-inkydink.

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Bladestorm04 t1_jb8scnx wrote

But if we didn't see this one, we'd see the next one. This has happened so many times it's almost impossible for it to not be happening when we're looking

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Phenotyx t1_jba5094 wrote

super novae are only decreasing in frequency also, so the further back you look (until you get to periods before super novae were possible) the more likely it is you see one.

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tropicsun t1_jb8hlln wrote

Does gravitational lensing of light and time occur at a 1:1 ratio?

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Hopefound t1_jb8snne wrote

I would imagine that the answer is yes since light is just a phenomena that traverses space and time. Light can’t be impacted separate from the space time it travels through as I understand it.

Also, I could be super wrong and have no idea what I’m talking about, math is hard and I am dumb.

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ImJKP t1_jb9ebvm wrote

Light travels at a constant velocity in a straight line through space. Gravitational lensing is an artifact of the kinks in spacetime created by massive objects; those kinks change what a "straight line" is for the light passing through that area of spacetime.

Time isn't affected by gravitational lensing per se. Gravity warps spacetime, and light is distorted (lensed) by the warped spacetime.

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entotheenth t1_jba58mu wrote

I was thinking it’s been bent so much it added 3 light years which sounds like a lot till you take into account that’s over a 3.2 billion light year trip.

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longleaf4 t1_jbabn7a wrote

I'm confused. Wasn't Webbs' first picture taken last year? How are they 1000 days from the first pic?

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RevengencerAlf t1_jbak72r wrote

It's all one picture. Due to gravitational lensing light emitted 1000 days apart in time reached the telescope at the same time. Basically the light from the first picture took 1000 days longer to reach us because the fabric of spacetime was curved forcing it to take a longer path while light emitted 1000 days later missed that gravity source so it was able to take the short route and get here at basically the same time.

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Bob_Sconce t1_jbb313v wrote

So, here's the question: In the big-bang, everything ejected from this one point and spread throughout the cosmos. We are, at this moment, some distance from where that occurred at a location I'll call "X." This photo claims to show light emitted not long after the big bang. It's not possible to travel faster than light.

Q:. How did we get to X faster than the light?

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bimundial t1_jbbqoiz wrote

There is no X. Things didn't get ejected, everything was extremely close to everything else, and of a sudden they started to get far away from everything else. It's like the surface of a baloon, if you inflate it, everything is further apart, there is no "point of ejection" on the surface.

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Bob_Sconce t1_jbbs5br wrote

That doesn't really help -- if everything was extremely close to everything else, then just pick 'X' to be the geographic center of all of that -- the exact center of the uninflated balloon if you like. At the beginning, we may not have been precisely at X, but we were very very close to it.

(Also, I intended X to be where we are now, not where the mass that is currently the earth was at the point of the big bang. But, that was not at all clear, so I'm just going with 'X= point of the big bang.')

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bimundial t1_jbbwvbm wrote

A ballon's surface doesn't have a center. If you inflate it, its area will grow at the same rate everywhere. You can put a point in any place of a sphere's surface and none of them will be the center, that's how it goes with the universe too, as far as I know.

So the big bang is basically that, it was a smaller area, maybe infinitesimaly smaller area, that just got bigger everywhere. Everything was just farther apart. There was no center before, there isn't one now, just like a inflated sphere surface.

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Bob_Sconce t1_jbcds33 wrote

? The surface doesn't have a center, but the balloon does. If all the mass was on the balloon surface, then there is a point inside the balloon that is, effectively, the center of mass of all that mass. That's X. And, presumably, not ALL of the mass expanded outward, otherwise there would be a massive empty space in the middle of the universe. (As far as I know, that hasn't been discovered.)

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bimundial t1_jbchal1 wrote

But the universe IS the surface. In this example, there is no inside. For an object placed upon the baloon, all that he sees is everything getting further apart, and that's how the universe behaves.

The universe was smaller, than it got bigger. It got bigger everywhere, in all directions, at the same rate. There is no 'X' direction where things got pushed out of, everything just got more distant from everything else.

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Bob_Sconce t1_jbd1wp7 wrote

So, things got more distant from each other at a rate that was faster than the speed of light?

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twistier t1_jbd3w5k wrote

The expansion of space does not have the speed limit that traveling through space has.

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bimundial t1_jbdvkmc wrote

Yep. That's because the things weren't getting distant inside space-time, but space-time itself was expanding between things. Relativity only puts a cap on the speed things move inside time-space, not the rate that time-space itself grows

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gyrofx t1_jbbev9q wrote

The way I understand it, there is no X, or put another way everything in the universe is point X.

Also, I'm dumb and maths is hard..

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Bensemus t1_jbfif90 wrote

> everything ejected from this one point and spread throughout the cosmos.

No. There is no centre everything exploded from. Infinite now, infinite then.

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