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Author Topic:   Coffee House Musing
AZPaul3
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Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


(2)
Message 1 of 112 (885570)
04-18-2021 8:57 PM


Astronomy
No debate topic, really, just an observation I think is significant.

In the last 20 years there has been a major shift in the conduct of astronomy. Not just the larger more powerful scopes on both land and in space that have become operational, which provide much deeper clearer views of the cosmos across most all of the EM spectrum, but, more significant is the way they have come operational.

Modern viewing on telescopes is digital, not optical. CCDs (charge-coupled devices) and other gizmos convert what the astronomer would have seen in optical to digital data stored in computer databases. The beauty is that these gizmos don’t just blip a signal when they are hit by a photon but, these days, they record the frequency, energy, amplitude, polarity, birth date and social security number of every photon they see. Ok, maybe not those last two.

Every major telescope on the planet has gone digital. Gone are the days when you had to request physical time on the scope then travel to the scope to sit in a freezing dome all night taking pretty pictures on emulsion.

You can still request time for specific views but, better yet, if an adequate view is already in the database you don’t have to wait. The astronomer then writes code, or more usual they have their grad students write most of it, to extract the data from the database and they code more programs to analyze and display the data and still more code to build simulations using the data. Collaborations are now going on to catalogue all the world’s scope’s databases into a database of databases available on-line. Download the few hundred gigabytes you want and start programming.

By scientific requirement specs and by international agreement, with a few exceptions, all the new scopes being built and planned will be required to dump their data eventually into databases available on-line without charge to the world. Astronomer/programmers, amateur/astronomer/programmers, home nutjob/astronomer/programmers, all have access. Vera Rubin, a monster scope being built in Chile, is expected to dump into their database, don’t hold me to this precise number, more than few terabytes of data each day. Even the new Chinese super huge FAST telescope (an Arecibo replacement) will participate in a limited way.

Astronomy has become computer programming and data mining. After the math, programming is the most required skill to be an astronomer. If you can program, astronomy is now a stay-at-home cottage industry open to anyone with internet access.

Imagine what we are going to find.

Edited by AZPaul3, : No reason given.

Edited by AZPaul3, : title


Eschew obfuscation. Habituate elucidation.

Replies to this message:
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


Message 11 of 112 (885612)
04-20-2021 2:36 PM
Reply to: Message 5 by Phat
04-20-2021 11:53 AM


Re: Astronomy
This whole math thing is no replacement for woo.

Good one, Phat.

But, someone's going to think you're serious. Prepare for the rumble.

Yes, people, Phat does have a sense of humor.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


Message 13 of 112 (885615)
04-20-2021 2:57 PM
Reply to: Message 9 by dwise1
04-20-2021 2:09 PM


Re: Astronomy
All I could think of was that accidental pun and so chose "DWise1" as my screen name.

I like my theory of your name better. You were trying to warn people of both the intellect and humor headed their way.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


(2)
Message 22 of 112 (886103)
05-06-2021 5:39 AM
Reply to: Message 21 by Tanypteryx
05-05-2021 10:58 PM


Re: Clever Studies in Astrophysics
Do gravity waves have an effect like the electromagnetic red-shift from cosmic expansion?

Apparently, yes. Not to be confused with "gravitational redshift" where a photon expends energy to leave the gravity well.

https://arxiv.org/pdf/1312.1862v2.pdf

Is it coincidence or is there an obvious link between gravity and light that I am overlooking?

The tie in to Maxwell from Special Relativity shows the "speed of causality" in the equations. GR gives the same constraints on gravity wave propagation as does Maxwell show for EM.

Edited by AZPaul3, : No reason given.

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 21 by Tanypteryx, posted 05-05-2021 10:58 PM Tanypteryx has responded

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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


Message 24 of 112 (886106)
05-06-2021 6:43 AM
Reply to: Message 23 by jar
05-06-2021 6:06 AM


Re: SN15
That's one in a row.

Eschew obfuscation. Habituate elucidation.

This message is a reply to:
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


(1)
Message 28 of 112 (887684)
08-19-2021 10:51 PM
Reply to: Message 27 by Tanypteryx
08-19-2021 9:15 PM


Re: Mapping the Universe’s Earliest Structures
A question occurs to me that maybe Son Goku can answer or give us the leading hypothesis.

Before the big brains get here let me tackle these just to see if I’m generally right.

Why doesn't dark matter clump together like regular matter does, in denser and denser clumps?

The major issue with dark matter is it appears to not respond to any electromagnetic force. EM is the force that causes matter to clump. No EM no clump.

Since dark matter does not, as far as we can tell, respond to EM that means it cannot be seen, at any wavelength. Matter with no heat signature. No absorption or emission. Photons, apparently, just pass by or thru without any notice responding only to dark matter's gravitational field.

I usually see dark matter described as more amorphous halos around galaxies.

Have you seen the Bullet Cluster - Wikipedia?

We see two big lobes of gravity separated from their colliding galaxies. We know it’s there because of the gravitational lensing of objects in the background. Milky Way is hypothesized to be wrapped in a dark matter fog out to twice+ our visible stellar population.

Is the repulsive force of dark energy acting more strongly on dark matter than normal matter?

Doesn’t appear so. Dark energy affects all of space equally. It’s progressive that way. Definitely not republican.

Dark matter adds to the gravitational field overcoming the minor dark energy expansion in local space like galaxies and galaxy clusters but I haven’t heard of dark matter being affected by, or exhibiting, any properties or forces other than gravity.

That's the rub. We can see "Dark Matter: The Gravity" but that's it. What it is? Right now we got nothing.

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 27 by Tanypteryx, posted 08-19-2021 9:15 PM Tanypteryx has responded

Replies to this message:
 Message 29 by LamarkNewAge, posted 08-20-2021 10:56 PM AZPaul3 has responded
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


(1)
Message 30 of 112 (887710)
08-20-2021 11:55 PM
Reply to: Message 29 by LamarkNewAge
08-20-2021 10:56 PM


Re: Dark Energy does not add any extra "space" to Space in a galaxy.
It does not add any (or very much) space between near galaxies. An example is the space between Andromeda and our own Milky Way.

Of course it does and locally, like I said, the expansion is minor on galactic scales.

You mentioned Andromedea. 2.5 Million LY of space between us. If I have my sums right the space between us and Andromedea is expanding at about 58 km/sec. Yet even with this increased distance the radial velocity of Andromeda's approach due to gravity is over 110 km/sec.

Dark Energy is expanding all of space everywhere even within and between galaxies. But the local gravity field is enough to counter those tensions.

It adds a massive amount of space when there is just about nothing but matterless space.

You want a mind blower? Even the space within an atom is expanding due to dark energy.

The old textbooks are fascinating to read but I am in awe of the true darkness that existed in science before the discovery of Dark Energy.

What are you talking about? What darkness in science?

That darkness started lifting 300 years ago and these last 100 years of science has been the brightest intellectual period of our species' history.

Are you complaining that cosmologists didn't discover dark matter and dark energy before there was any evidence for them?

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 29 by LamarkNewAge, posted 08-20-2021 10:56 PM LamarkNewAge has responded

Replies to this message:
 Message 31 by LamarkNewAge, posted 08-21-2021 12:04 AM AZPaul3 has responded
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


(1)
Message 33 of 112 (887713)
08-21-2021 12:28 AM
Reply to: Message 31 by LamarkNewAge
08-21-2021 12:04 AM


Re: Dark Energy does not add any extra "space" to Space in a galaxy.
And the scientific community was universally wrong to say that the expansion of space was slowing down, when in fact it was speeding up by leaps and bounds

And once the consensus was that the Milky Way was the full extent of the universe.

It wasn't. We learned more and changed our view. Science does that every day of the week and twice on Tuesdays.

So you are upset that science did not see the unknown coming.

Explain yourself.

About what?

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 31 by LamarkNewAge, posted 08-21-2021 12:04 AM LamarkNewAge has responded

Replies to this message:
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


(1)
Message 35 of 112 (887715)
08-21-2021 1:59 AM
Reply to: Message 34 by LamarkNewAge
08-21-2021 12:40 AM


Re: Dark Energy does not add any extra "space" to Space in a galaxy.
You combined my two separate issues, in a single response, which I told you not to do.

Just to start out on the right foot, I really don't give a flyin' fuck what you "told" me to do.

The "explain yourself" was about your statement that Dark Energy is beginning to rip atoms apart.

Reading comprehension problem. Re-read what I wrote. I never said Dark Energy is beginning to rip atoms apart.

Though the Big Rip - Wikipedia is an interesting hypothesis that posits exactly that.

Dark energy is hypothesised to be a property of the vacuum energy of space. Every cubic planck length of space everywhere in the universe, so the story goes, is expanding.

The other four forces are, presently anyway, strong enough to counter that expansion so that, yes in your example, the space within the atoms, between the electrons, between the quarks, everywhere, all of it, is expanding but the nuclear forces and the EM force keep the atom intact right where she stands. Space expands in and around the atom without the atom altered to any extent.

Since atoms already have much space within themselves, then what is Dark Energy doing to that space? What known force is competing with the Dark Energy "force" (if that is what it is, as opposed to a field)?

Learn your physics. Force (energy) is the length of a spacetime 4-vector in the time direction. Which means in quantum mechanics energy is a vibration in the various quantum fields mediated by specific elementary force carriers (bosons).

These forces and the particles they interact with exist in the fabric of a spacetime under a mathematical model we call a Minkowski space. All that means is it's a 3-D spacetime with the math of relativity laid in.

This describes our universe. The ΛCDM model.

In this description dark energy is not mediated by an actual particle, we don't think, and cannot be separated from any volume of space. It is an intrinsic property of space. There are a number of hypotheses on how the mechanism is supposed to work but none of them involve disturbing anything made with particles from our Standard Model.

If the force of dark energy, the cosmological constant, H0, increases over time the Big Rip posits it could expand so fast and explosively that even the fundamental forces could not hold the expansion pressure at bay and everything including the nucleus of atoms would disintegrate.

Most see this proposal as highly unlikely but it is possible, so says the math in our model.

Are you answers snd/or statements universally considered certain?

You don't understand science very well, do you. Nothing is ever certain. Always pending further data.

What I've been posting is my best recollection and (lazy) research on the present state of our knowledge. Some details may be fuzzy but this is, in general, the way I understand we see it today.

I expect to be corrected, but certainly not by you.

Edited by AZPaul3, : No reason given.

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 34 by LamarkNewAge, posted 08-21-2021 12:40 AM LamarkNewAge has responded

Replies to this message:
 Message 36 by LamarkNewAge, posted 08-21-2021 2:42 AM AZPaul3 has responded
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


(2)
Message 38 of 112 (887721)
08-21-2021 3:55 AM
Reply to: Message 36 by LamarkNewAge
08-21-2021 2:42 AM


Re: Dark Energy does not add any extra "space" to Space in a galaxy.
Earlier, you were asked whether Dark Energy affected Dark Matter and Baryonic Matter in a different way. You then went on to talk about how it pulled space the same everywhere.

Wow, your reading comprehension is bad.

Dark energy has no effect on matter, any matter as far as I can tell, other than to separate it further in space if that matter is already separated to the extent that the gravitational field is too weak to negate the expansion.

And, no, dark energy doesn’t pull anything. It pushes. It pushes on every spot in space to expand that space in every direction.

You then said, just now, that it was probably an unchanging force, right?

No. Never said anything about any unchanging force. I talked about one proposal that posits catastrophic change (Big Rip). There are others where the hypothesized H0 changes not all that much. But, Lamark, I never mentioned any unchanging force.

But earlier, I made mention of the pre-Dark Energy discovery period, which considered the entirely of matter and space to be potentially able to close back to a singularity. So the expansion of space was tied to a theory that matter could be pushed together as the whole of space in the universe shrunk.

That is still a very plausible scenario. If H0 peaks then subsides over time then a Big Crunch - Wikipedia may be in the cards.

You say you were just talking about space being created everywhere.

And so it is.

But the initial question, from another, was about the knowledge that Dark Matter( probably full of it's own particles) contributes to gravity ( do you feel gravity has a field particle?) and whether Dark Energy has a different repulsive force on that type of combo.

Tanypteryx’s questions in his Message 27 had to do with both dark matter and dark energy. So, I answered both.

Is there a problem in that?

You now want to say that you never intended to imply that Dark Energy did anything but create/expand space. It is all about Gravity and Dark Energy? Just 2 forces?

What are you going on about? Gravity and dark energy are the topic of the discussion.

So “It is all about Gravity and Dark Energy? Just 2 forces?”

Yeah, that is what this discussion centered on.

Of course dark energy expands space. Well, something is, we just call it dark energy because we don’t know squat about what’s happening ‘cept that space is expanding.

Look. Let me make this clear for your reading comprehension problem.

Dark energy makes space expand. All of it. Everywhere. All the time. It has no effect on matter as long as that matter is under a strong enough gravitational field. That’s it. That’s all we know about it.

Dark matter makes gravity. Don’t ask how. Take your pick. Either warps in spacetime or the interaction of gravitons in a quantum field. It doesn’t seem to react to EM so we can’t see it. We only see the gravity field. That’s it. That’s all we know about it.

I guess I will just say, in the form of a question, "Just what Do particles have to do with it?"

Uhh, everything. We can’t talk energy, matter, dark, baryonic or anything else without particles.

What do you think we’re talking about?

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 36 by LamarkNewAge, posted 08-21-2021 2:42 AM LamarkNewAge has responded

Replies to this message:
 Message 40 by LamarkNewAge, posted 08-22-2021 1:49 PM AZPaul3 has responded

  
AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


Message 39 of 112 (887722)
08-21-2021 4:03 AM
Reply to: Message 37 by LamarkNewAge
08-21-2021 3:06 AM


Re: Dark Energy does not add any extra "space" to Space in a galaxy.
I still have a problem with the idea that concentrated matter ( like our Earth and atmosphere) does not counter the creation of space. I feel that space expansion can hypothetically be static. I just don't see why (local) matter does not stop it completely (in its neck of the woods)

Why am I wrong?

Why should concentrated matter be a stop to spatial expansion? Your concentrated matter is composed mostly of empty space already. What's to stop that space from expanding?


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


Message 42 of 112 (887807)
08-22-2021 3:00 PM
Reply to: Message 40 by LamarkNewAge
08-22-2021 1:49 PM


Re: Dark Energy does not add any extra "space" to Space in a galaxy.
What is the observational evidence that Dark Energy is constantly creating space between you and me?

First, the expansion is only significant at large scales. If I have my sums right the spatial expansion in each cubic kilometer of our local space, in theory in all of space, is on the order of 0.00007 mm per year. I don't think we have the technology to measure this. At 3,250,000 LY distance that (should) equal about 70 km/s.

Second, it's a logical extension of the cosmological principle. We here in this space is nowhere special and thus the vacuum pressure seen in space 3,250,000 LY away, which we can measure, is the same and contains the same properties as the space over here.

Not to conflict with Percy, above, but the cosmological principle is an assumption. There is no logical reason nor evidence that this principle is violated by dark energy. To posit otherwise without evidence is like saying there is a different god to control the properties of each individual atom. I wouldn't put it past you to believe this.

We have evidence that reasonably extends dark energy vacuum pressure being an intrinsic property of space, all space, with no exceptions. Which reasonably makes the space between you and me also expand just like all of space everywhere.

How would you challenge this, other than personal incredulity?

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 40 by LamarkNewAge, posted 08-22-2021 1:49 PM LamarkNewAge has responded

Replies to this message:
 Message 46 by LamarkNewAge, posted 08-22-2021 7:03 PM AZPaul3 has responded
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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


Message 44 of 112 (887811)
08-22-2021 3:55 PM
Reply to: Message 43 by Tanypteryx
08-22-2021 3:14 PM


Re: Mapping the Universe’s Earliest Structures
Excellent questions. I hope I can do them justice.

Do you remember a demo done on the ISS with a bag of salt? Without any prompting the small grains would bump and stick together.

That is the electrostatic force that is causing the grains to adhere.

If dark matter is some kind of strange particle then it should react the same way and clump into larger structures like the salt in those baggies. But, apparently, dark matter does not react to EM forces so there is no electrostatic cling. That would mean the dark matter particles would be billiard balls banging into, not clinging, then bouncing off each other. Equal and opposite reaction stuff.

The gravitational attraction is too weak at that scale to keep the particles together.

Think a balloon of gas. The gravity may weakly draw some molecules together but being electrically neutral they do not adhere but only bounce off each other. Vibrational motion is an intrinsic property of all matter above 0oK. Dark matter is, we think, not just EM neutral but EM immune and will jitterbug all over the place without anything to slow them down. Can't keep a dust bunny together.

Also think this. Dark matter may be immune to gravity as well as EM. Dark matter may not be matter-like at all. May not be matter at all.

Does this help?

Edited by AZPaul3, : No reason given.

Edited by AZPaul3, : No reason given.

Edited by AZPaul3, : No reason given.

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 43 by Tanypteryx, posted 08-22-2021 3:14 PM Tanypteryx has responded

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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


Message 48 of 112 (887821)
08-22-2021 7:34 PM
Reply to: Message 46 by LamarkNewAge
08-22-2021 7:03 PM


Re: Dark Energy does not add any extra "space" to Space in a galaxy.
Answered in Message 42. Pay attention.

Edited by AZPaul3, : No reason given.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 46 by LamarkNewAge, posted 08-22-2021 7:03 PM LamarkNewAge has responded

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AZPaul3
Member
Posts: 6034
From: Phoenix
Joined: 11-06-2006
Member Rating: 3.7


(2)
Message 51 of 112 (887825)
08-22-2021 8:19 PM
Reply to: Message 50 by LamarkNewAge
08-22-2021 8:06 PM


Re: Dark Energy does not add any extra "space" to Space in a galaxy.
actually uttered "god" ...

Yes I did ... in an analogy. Talk of religion bothers you?

... and then had the audacity to attribute it to me.

Did no such thing.

quote:
To posit otherwise without evidence is like saying there is a different god to control the properties of each individual atom. I wouldn't put it past you to believe this.

That attributes nothing to you. It questions your intellect.

Nuance doesn't occur to you, does it.


Eschew obfuscation. Habituate elucidation.

This message is a reply to:
 Message 50 by LamarkNewAge, posted 08-22-2021 8:06 PM LamarkNewAge has responded

Replies to this message:
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