APOD: Time Spiral (2024 Jul 01)

[APOD Robot]

Time Spiral

Explanation: What's happened since the universe started? The time spiral shown here features a few notable highlights. At the spiral's center is the Big Bang, the place where time, as we know it, began about 13.8 billion years ago. Within a few billion years atoms formed, then stars formed from atoms, galaxies formed from stars and gas, our Sun formed, soon followed by our Earth, about 4.6 billion years ago. Life on Earth begins about 3.8 billion years ago, followed by cells, then photosynthesis within a billion years. About 1.7 billion years ago, multicellular life on Earth began to flourish. Fish began to swim about 500 million years ago, and mammals because walking on land about 200 million years ago. Humans first appeared only about 6 million years ago, and made the first cities only about 10,000 years ago. The time spiral illustrated stops there, but human spaceflight might be added, which started only 75 years ago, and useful artificial intelligence began to take hold within only the past few years.

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[Eclectic Man]

“The story so far:
In the beginning the Universe was created.
This has made a lot of people very angry and been widely regarded as a bad move.”

― Douglas Adams, The Restaurant at the End of the Universe, Hitch-Hiker's Guide to the Galaxy

(Sorry, couldn't resist. Have a nice day everyone)

[Roy]

The Ammonoid of conjecture, paleontology, and history. Hard to put everything on the same time scale.

[Brookemyersinstl@gmail.com]

Is the time spiral illustration available for purchase?

[Locutus76]

Is the time spiral illustration available for purchase?

You can freely use the image as it has a Creative Commons BY-SA 4.0 license:
https://creativecommons.org/licenses/by-sa/4.0/

[Cousin Ricky]

Humans first appeared only about 6 million years ago, ...

That’s a rather broad definition of “human.” 6 million years ago is when our lineage split from the chimpanzee/bonobo lineage, so this definition would include Australopithecus and Ardipithecus. I’ll take it, though.

[Chris Peterson]

Humans first appeared only about 6 million years ago, ...

That’s a rather broad definition of “human.” 6 million years ago is when our lineage split from the chimpanzee/bonobo lineage, so this definition would include Australopithecus and Ardipithecus. I’ll take it, though.

Probably would be better to frame it as the appearance of the genus Homo, about 2 million years ago. Makes more sense in considering the origin of humans.

[zendae]

“The story so far:
In the beginning the Universe was created.
This has made a lot of people very angry and been widely regarded as a bad move.”

― Douglas Adams, The Restaurant at the End of the Universe, Hitch-Hiker's Guide to the Galaxy

(Sorry, couldn't resist. Have a nice day everyone)

Thank you! I just love to start the day with a true laugh!

[ww1y]

"Within a few billion years, atoms formed," while technically correct, is somewhat misleading. Unless JADES-GS-z14-0 is made up of something other than atoms?

[Chris Peterson]

"Within a few billion years, atoms formed," while technically correct, is somewhat misleading. Unless JADES-GS-z14-0 is made up of something other than atoms?

The failure is the lack of a comma after "Within a few billion years" in the caption. A problem you have corrected here, and which makes the entire sentence much better.

[Syringa vulgaris]

The honest answer is, we don't know. We have some conjectures, but most of these are just that.

[Chris Peterson]

The honest answer is, we don't know. We have some conjectures, but most of these are just that.

We don't know what? The vast majority of stuff on the spiral we know with a high degree of confidence due to robust evidence.

[johnnydeep]

Is the time spiral illustration available for purchase?

You can freely use the image as it has a Creative Commons BY-SA 4.0 license:
https://creativecommons.org/licenses/by-sa/4.0/

And you can also buy a much higher resolution image for $15 from the author here: https://payhip.com/pablocarlosbudassi/c ... fographics

He's got many other very cool images for sale as well!

[Syringa vulgaris]

Really, now?

We don't know if there was a big bang, it is a hypothesis without any evidence to support it.

We have no idea what is this "inflation", except we know it must have violated all assumptions that are the foundation of modern physics.

We have no idea how things were in the part that says "SMB" and "dark ages".

Our current beliefs about the timeline of the appearance of stars and galaxies, the very first thing we can actually measure, appear to be very wrong.

Most of the remaining "spiral" (the outer 3 rings or so) is concerned with very local phenomena compared to what we believe is the size of the visible Universe.

And even there we can't see 80% of the phenomenon that acts on the visible stuff through gravity.

But yeah, let's pretend we can answer a question like "What's happened since the universe started?".

We can hypothesize, and make some claims about a small part of the Universe, but that's about all.

We know a few things, but let's not pretend a whole lot is set in stone.

[Chris Peterson]

Really, now?

We don't know if there was a big bang, it is a hypothesis without any evidence to support it.

We have no idea what is this "inflation", except we know it must have violated all assumptions that are the foundation of modern physics.

We have no idea how things were in the part that says "SMB" and "dark ages".

Our current beliefs about the timeline of the appearance of stars and galaxies, the very first thing we can actually measure, appear to be very wrong.

Most of the remaining "spiral" (the outer 3 rings or so) is concerned with very local phenomena compared to what we believe is the size of the visible Universe.

And even there we can't see 80% of the phenomenon that acts on the visible stuff through gravity.

But yeah, let's pretend we can answer a question like "What's happened since the universe started?".

We can hypothesize, and make some claims about a small part of the Universe, but that's about all.

We know a few things, but let's not pretend a whole lot is set in stone.

The Big Bang is not a hypothesis, it is a theory, and one which is well supported by multiple independent lines of objective evidence. The existence of inflation is similarly well supported, and doesn't violate any physical principles. We observe the CMB (which I assume is what you mean), and while we can't observe the "dark ages" in the electromagnetic spectrum, it is in principle observable. Our understanding of the formation of stars and galaxies is unlikely to be "wrong", simply incomplete.

I don't think you understand science very well.

[johnnydeep]

Really, now?

We don't know if there was a big bang, it is a hypothesis without any evidence to support it.

We have no idea what is this "inflation", except we know it must have violated all assumptions that are the foundation of modern physics.

We have no idea how things were in the part that says "SMB" and "dark ages".

Our current beliefs about the timeline of the appearance of stars and galaxies, the very first thing we can actually measure, appear to be very wrong.

Most of the remaining "spiral" (the outer 3 rings or so) is concerned with very local phenomena compared to what we believe is the size of the visible Universe.

And even there we can't see 80% of the phenomenon that acts on the visible stuff through gravity.

But yeah, let's pretend we can answer a question like "What's happened since the universe started?".

We can hypothesize, and make some claims about a small part of the Universe, but that's about all.

We know a few things, but let's not pretend a whole lot is set in stone.

The Big Bang is not a hypothesis, it is a theory, and one which is well supported by multiple independent lines of objective evidence. The existence of inflation is similarly well supported, and doesn't violate any physical principles. We observe the CMB (which I assume is what you mean), and while we can't observe the "dark ages" in the electromagnetic spectrum, it is in principle observable. Our understanding of the formation of stars and galaxies is unlikely to be "wrong", simply incomplete.

...

What do you mean by being "in principle observable"? (assuming the "dark ages" was the period of time from the BB to about 380,000 years when photons were freed to travel)

[Chris Peterson]

Really, now?

We don't know if there was a big bang, it is a hypothesis without any evidence to support it.

We have no idea what is this "inflation", except we know it must have violated all assumptions that are the foundation of modern physics.

We have no idea how things were in the part that says "SMB" and "dark ages".

Our current beliefs about the timeline of the appearance of stars and galaxies, the very first thing we can actually measure, appear to be very wrong.

Most of the remaining "spiral" (the outer 3 rings or so) is concerned with very local phenomena compared to what we believe is the size of the visible Universe.

And even there we can't see 80% of the phenomenon that acts on the visible stuff through gravity.

But yeah, let's pretend we can answer a question like "What's happened since the universe started?".

We can hypothesize, and make some claims about a small part of the Universe, but that's about all.

We know a few things, but let's not pretend a whole lot is set in stone.

The Big Bang is not a hypothesis, it is a theory, and one which is well supported by multiple independent lines of objective evidence. The existence of inflation is similarly well supported, and doesn't violate any physical principles. We observe the CMB (which I assume is what you mean), and while we can't observe the "dark ages" in the electromagnetic spectrum, it is in principle observable. Our understanding of the formation of stars and galaxies is unlikely to be "wrong", simply incomplete.

...

What do you mean by being "in principle observable"? (assuming the "dark ages" was the period of time from the BB to about 380,000 years when photons were freed to travel)

Electromagnetic radiation isn't the only medium we have for observation. Gravity waves (which we are increasingly able to detect) might provide a way of looking at the Universe during a time when it was optically opaque.

[johnnydeep]

The Big Bang is not a hypothesis, it is a theory, and one which is well supported by multiple independent lines of objective evidence. The existence of inflation is similarly well supported, and doesn't violate any physical principles. We observe the CMB (which I assume is what you mean), and while we can't observe the "dark ages" in the electromagnetic spectrum, it is in principle observable. Our understanding of the formation of stars and galaxies is unlikely to be "wrong", simply incomplete.

...

What do you mean by being "in principle observable"? (assuming the "dark ages" was the period of time from the BB to about 380,000 years when photons were freed to travel)

Electromagnetic radiation isn't the only medium we have for observation. Gravity waves (which we are increasingly able to detect) might provide a way of looking at the Universe during a time when it was optically opaque.

Ok, thanks. I always seem to forget about gravitational waves (note: not gravity waves which are about fluid dynamics).

[Chris Peterson]

What do you mean by being "in principle observable"? (assuming the "dark ages" was the period of time from the BB to about 380,000 years when photons were freed to travel)

Electromagnetic radiation isn't the only medium we have for observation. Gravity waves (which we are increasingly able to detect) might provide a way of looking at the Universe during a time when it was optically opaque.

Ok, thanks. I always seem to forget about gravitational waves (note: not gravity waves which are about fluid dynamics).

Yes, gravitational waves. Who knows with what resolution and sensitivity we'll eventually be able to measure them, even to image with them. And I wonder about particles like neutrinos or dark matter, which might be unaffected by passing through neutral hydrogen. Lacking the technology, at the moment, to observe the dark ages doesn't mean they aren't observable.

[johnnydeep]

Electromagnetic radiation isn't the only medium we have for observation. Gravity waves (which we are increasingly able to detect) might provide a way of looking at the Universe during a time when it was optically opaque.

Ok, thanks. I always seem to forget about gravitational waves (note: not gravity waves which are about fluid dynamics).

Yes, gravitational waves. Who knows with what resolution and sensitivity we'll eventually be able to measure them, even to image with them. And I wonder about particles like neutrinos or dark matter, which might be unaffected by passing through neutral hydrogen. Lacking the technology, at the moment, to observe the dark ages doesn't mean they aren't observable.

[zendae]

"Dark energy overtakes gravity."

Is this because gravity was universally weak at this stage due to less matter? I am not sure what exactly this statement really implies. What would be the difference between the Universe with no dark energy and the Universe after dark energy "overtook" gravity? I know that gravity is far, far, far weaker than the strong force, yet virtually nothing - perhaps absolutely nothing - overtakes gravity at a certain point. Yet do we even know why gravity has any power at all? I can defeat gravity by picking up a feather off the ground. Seemingly nothing defeats gravity at or beyond an event horizon. But even those two examples are local ones. A universal "overtaking" means what?
The term "overtakes" in the quote has me.

[Chris Peterson]

"Dark energy overtakes gravity."

Is this because gravity was universally weak at this stage due to less matter? I am not sure what exactly this statement really implies. What would be the difference between the Universe with no dark energy and the Universe after dark energy "overtook" gravity? I know that gravity is far, far, far weaker than the strong force, yet virtually nothing - perhaps absolutely nothing - overtakes gravity at a certain point. The term "overtakes" in the quote has me.

This is the point where the expansion rate of the Universe transitioned from slowing to speeding up. Where the "force" of dark energy became greater than the "force" of gravity.

[zendae]

Thanks Chris. I expanded my question, but it wasn't necessary.

[johnnydeep]

"Dark energy overtakes gravity."

Is this because gravity was universally weak at this stage due to less matter? I am not sure what exactly this statement really implies. What would be the difference between the Universe with no dark energy and the Universe after dark energy "overtook" gravity? I know that gravity is far, far, far weaker than the strong force, yet virtually nothing - perhaps absolutely nothing - overtakes gravity at a certain point. The term "overtakes" in the quote has me.

This is the point where the expansion rate of the Universe transitioned from slowing to speeding up. Where the "force" of dark energy became greater than the "force" of gravity.

So this question just occurred to me: how much weaker (or stronger) is dark energy compared to gravity? Say, given two protons separated by a meter, how does their mutual attraction due to gravity compare to the dark energy expansion force due to the spatial separation between them?

[AVAO]

"Within a few billion years, atoms formed," while technically correct, is somewhat misleading. Unless JADES-GS-z14-0 is made up of something other than atoms?

Pablo Carlos Budassi created this image for Wikimedia.org in 2020, i.e. "long" before WEBB started its work.

Nevertheless, your criticism is justified and worth discussing. The poster shows very well what challenges WEBB's latest findings pose for the cosmological standard model that has been established for almost 100 years.


Let's look at the APOD from June 24, 2024 ( https://apod.nasa.gov/apod/ap240624.html ).
"Pictured in the inset box is JADES-GS-z14-0, a faint smudge of a galaxy that formed only 300 million years after the universe started."

Click to view full size image

Well, even if new scientific facts challenge older models, these older models should be retained until they can be replaced by improved or alternative explanatory models.