Energy Vs Dark Energy

[hazelm]

Question:  I know we do not really know what Dark Energy is but is it in any way related to what we normally call energy in physics?  Or do we suspect it might be related?  Thanks.

[GAHD]

AFAIK Dark Energy is just the energy of Space itself. The Quantum Foam.
 
Good Talk on it.
That what you were getting at, or did I misread?

Edit: THIS might be more what you're looking for. Around 22 mins in if you want to skip preamble.

[hazelm]

AFAIK Dark Energy is just the energy of Space itself. The Quantum Foam.

 

Good Talk on it.

That what you were getting at, or did I misread?

 

Edit: THIS might be more what you're looking for.

Thank you.  I'll have to listen to him more than once.  He loses me.  But, yes, I think that is it.  I think he is saying it is two different

forms of energy and not related.  I'll do it again.  it will be easier to understand second time around.  The Quantum Foam.  Seems I've read about that recently.  I'll find that, too.

 

The place and actions of energy in our universe keeps me fascinated.  That and the vibrations that result.  Somewhere, somehow, it all ties together.

[A-wal]

For the expansion model to work it requires that it expanded slower in the past. Dark energy is just the name given to the unknown (quantum foam (pressure I presume) might be one idea but there is no excepted explanation for dark energy) energy that's causing the supposed expansion to speed up.

 

Although the fact that the further away a galaxy is (the further back in time we're seeing it), the faster it's supposed to be moving away from us means that the expansion would be slowing down over time, not speeding up. What a complete mess!

[GAHD]

For the expansion model to work it requires that it expanded slower in the past. Dark energy is just the name given to the unknown (quantum foam (pressure I presume) might be one idea but there is no excepted explanation for dark energy) energy that's causing the supposed expansion to speed up.

 

Although the fact that the further away a galaxy is (the further back in time we're seeing it), the faster it's supposed to be moving away from us means that the expansion would be slowing down over time, not speeding up. What a complete mess!

Complete mess or not, it's what's observed. You CAN flip it on it's head with the observed data too: The universe isn't really expanding so much as 'everything' in it is shrinking(including light). That doesn't really HELP with the mess, but it's a thing you can ponder.

 

That second origins talk I linked goes a little more in depth on it, and it's great fodder for the brain to look at it abstractly though the lense of jargon that tried to convey meaning. To really get what's being talked about though, it could be useful to look into raw datasets and how that data was generated. Doing that myself I've come across the language barriers inherent in english (and to some degree math), particularly with "negatinve/anti/opposed" "-" and "nothing/void/absence" "0" as terminologies. It's very much a "learn by doing" arena, and one that can need some very specific material to play with. EG Magnetic Monopole metamaterials, or other metamaterials exploiting casimir effect.  Both of wich offer insight into dark energy, and "space/nothing/void/ether" in their own ways.

 

Not quite sure if I was very lucid in conveying the intended point there, I'm going to blame it on that danged jargon issue.

[hazelm]

For the expansion model to work it requires that it expanded slower in the past. Dark energy is just the name given to the unknown (quantum foam (pressure I presume) might be one idea but there is no excepted explanation for dark energy) energy that's causing the supposed expansion to speed up.

 

Although the fact that the further away a galaxy is (the further back in time we're seeing it), the faster it's supposed to be moving away from us means that the expansion would be slowing down over time, not speeding up. What a complete mess!

Maybe we will move to one of Andrei Linde's baby universes. :-) 

[hazelm]

Complete mess or not, it's what's observed. You CAN flip it on it's head with the observed data too: The universe isn't really expanding so much as 'everything' in it is shrinking(including light). That doesn't really HELP with the mess, but it's a thing you can ponder.

 

That second origins talk I linked goes a little more in depth on it, and it's great fodder for the brain to look at it abstractly though the lense of jargon that tried to convey meaning. To really get what's being talked about though, it could be useful to look into raw datasets and how that data was generated. Doing that myself I've come across the language barriers inherent in english (and to some degree math), particularly with "negatinve/anti/opposed" "-" and "nothing/void/absence" "0" as terminologies. It's very much a "learn by doing" arena, and one that can need some very specific material to play with. EG Magnetic Monopole metamaterials, or other metamaterials exploiting casimir effect.  Both of wich offer insight into dark energy, and "space/nothing/void/ether" in their own ways.

 

Not quite sure if I was very lucid in conveying the intended point there, I'm going to blame it on that danged jargon issue.

I have trouble understanding a lot of those videos. People talk too fast nowadays.  That adds to the problem.  Just another reason to like books.  Don't have to listen.

 

Following up on my original post this morning - the model of the universe and dark energy - I found that Upsala University lets you read their research articles and listen to university articles.  Sounds good until you are reminded that these are in Swedish.  :-(   

[GAHD]

I have trouble understanding a lot of those videos. People talk too fast nowadays.  That adds to the problem.  Just another reason to like books.  Don't have to listen.

 

Following up on my original post this morning - the model of the universe and dark energy - I found that Upsala University lets you read their research articles and listen to university articles.  Sounds good until you are reminded that these are in Swedish.  :-(   

Cornell does that too, in English, to a degree(pun intended). MIT as well though OpenCourseware, though OCW lags behind "cutting edge" quite a bit.

 

 

You CAN also slow down or speed up youtube videos to match your own processing speeds if you don't mind some odd register changes in voices. I personally find 1.25 or 1.5 times normal speeds to be easier to process, but there are options for lower ones if you prefer to ponder in between the lines rather than after them. I agree text is generally easier for personal pacing.

[hazelm]

Cornell does that too, in English, to a degree(pun intended). MIT as well though OpenCourseware, though OCW lags behind "cutting edge" quite a bit.

 

 

You CAN also slow down or speed up youtube videos to match your own processing speeds if you don't mind some odd register changes in voices. I personally find 1.25 or 1.5 times normal speeds to be easier to process, but there are options for lower ones if you prefer to ponder in between the lines rather than after them. I agree text is generally easier for personal pacing.

My trouble is my own.  I do not hear well.  So, unless a speaker is very clear and at a slow enough speed,  I struggle with it.  The younger people like to see how fast they can rattle.  If it is important I slow them down.  If not, I pretend and move on.  :-)

[A-wal]

Complete mess or not, it's what's observed.

No. It's what's inferred.

 

The fact that the more distant (and therefore the further back in time we're seeing it) a galaxy is, the more redshifted it is surely shows that the supposed expansion is speeding up rather than slowing down?

 

The fact that redshift is proportional to distance surely shows that the light is being redshifted on route because otherwise there wouldn't be this direct correlation between space covered/time in transit and the light's redshift?

 

Any alternate explanation is more complicated and requires further explanation.

 

You CAN flip it on it's head with the observed data too: The universe isn't really expanding so much as 'everything' in it is shrinking(including light). That doesn't really HELP with the mess, but it's a thing you can ponder.

That's exactly the same thing though. It's equivalent so there's no distinction. Like object A at rest with object B in motion and object A in motion with object B at rest.

 

Doing that myself I've come across the language barriers inherent in english (and to some degree math), particularly with "negatinve/anti/opposed"...

I've always thought that antimatter should be called negative mater (same thing with opposite charge) and negative matter should be called antimatter (complete opposite that pushes rather than pulls other massive objects).

 

Not quite sure if I was very lucid in conveying the intended point there, I'm going to blame it on that danged jargon issue.

You were.

[GAHD]

No. It's what's inferred.

Inferred might be a better word for it, you're right. Inferred from the observations. Hopefully the meaning isn't really lost from that word choice.

 

 

The fact that the more distant (and therefore the further back in time we're seeing it) a galaxy is, the more redshifted it is surely shows that the supposed expansion is speeding up rather than slowing down?

 

The fact that redshift is proportional to distance surely shows that the light is being redshifted on route because otherwise there wouldn't be this direct correlation between space covered/time in transit and the light's redshift?

 

Any alternate explanation is more complicated and requires further explanation.

 

That's exactly the same thing though. It's equivalent so there's no distinction. Like object A at rest with object B in motion and object A in motion with object B at rest.

I'm not sure if Hubble's Constant not-quite being "constant" is an issue though? As for other explanations... there's quite a few possible ones that arn't quite so "crazy" as they seem on first look. But that's another topic entirely. Ironically one that dovetails into that "equivalence" bit and can probably be disregarded.

I've always thought that antimatter should be called negative mater (same thing with opposite charge) and negative matter should be called antimatter (complete opposite that pushes rather than pulls other massive objects).

I'm not sure about antimatter & negative matter naming convention as you put them. I honestly think there needs to be some brand new or exotic nomenclature invented and used if the confusion is ever going to be addressed properly. This re-purposing and mutating of words and meaning causes no end of confusion. Something like IUPAC will probably get it done once it's more industrialized.

Though with how Imaginative they are, they'll probably just call them something like "BM1, BM2, NMB" which would be fine if it gets the job done.

[A-wal]

Inferred might be a better word for it, you're right. Inferred from the observations. Hopefully the meaning isn't really lost from that word choice.

It's an important distinction. We can't observe the universe expanding, let alone the expansion rate increasing over time. The inference that this is in fact what's happening is very odd.

 

I'm not sure if Hubble's Constant not-quite being "constant" is an issue though?

You mean an issue to the interpretation that redshifted being proportional to distance is showing us that the light must be shifted on route? If it's because the light traveled along a curved path from our perspective then it would vary slightly depending on the strength of gravity in the regions of space that it passed through to reach us.

 

As for other explanations... there's quite a few possible ones that arn't quite so "crazy" as they seem on first look.

Do any of them give any reason to think that redshift being caused by distance traveled isn't a much simpler explanation for redshift being proportional to distance?

 

Or explain how an expansion of the space between two objects is somehow distinct from the objects moving away from each other, faster than the speed of light in this case?

 

Or explain how the expansion could possibly be speeding up despite the fact that the further back in time we look, the faster the supposed expansion?

[GAHD]

Eh, a lot of it comes down to log-log graphs being straight lines and how long it takes cosmologists to realize T(A+B )=0 is equivalent to TA=-TB and A+B=1÷T
That's a supreme oversimplification but I don't really feel like re-wording the distilled observations and rational of thousands of people over a couple hundred years at the moment.

There's logic to it. The issue you seem to be having with HC seems to stem from a misunderstanding of additive properties, unless I'm misreading what you're getting at with "explain how the expansion could possibly be speeding up despite the fact that the further back in time we look, the faster the supposed expansion." Maybe rethink that part a bit, and review compound interest as they're really two sides of the same math.
That, or we're working from different datasets. Both are totally possible, and I'm open to the one's I've looked at being wrong if more accurate ones turn up. Quite a few experiments get their data FUBAR because of a failure in dimensional analysis. Hubble did exactly that on first pass, unless the variance is WILDLY outside of what's currently understood (again, possible, if unlikely).

 

[A-wal]

Maybe I'm massively oversimplifying but to me the fact that according to the expansion model, more distant (further back in time) galaxies are moving away from us faster and progressively slower the closer (less far back in time) the galaxy is to us means that the rate of the supposed expansion must be slowing down, not speeding up.

 

If the further back in time we look, the faster the expansion, how is the expansion not slowing down?

Edited December 30, 2018 by A-wal

[GAHD]

This is both a digression and not a digression so....

Let's look at this rationally.
Assume you're in one of the parts of the world where gravity acceleration is 9.8m/s/s  (it varies but averages are useful), and you have a vacuume chamber big enough so air resistance is not a factor in the following.
-you drop one ball (A) from 19.6 m
-you drop another ball (B ) from 9.8 m 1 second after the first

-When do they hit the ground?


Next: You have one $5 mutual fund at locked in APR 5%. started in 1999. You have another identical $5 one at 5% started in 2012. What are their values in 2018?

Next: You have one 450nm lightsource 20 ly away, another 450nm lightsource 10 ly away. Assuming HC acts like both the above examples combined, what nm will the wavelength of each lightsource be?

It's all in the compounds.

AFAICT you're confusing "father back = more compounded shift" for "farther back = more acceleration at that time" Do correct me if you think I'm misreading you so we're not talking past each other. :)

Edit: Something related...sorta.
 

[A-wal]

Assume you're in one of the parts of the world where gravity acceleration is 9.8m/s/s  (it varies but averages are useful), and you have a vacuume chamber big enough so air resistance is not a factor in the following.

-you drop one ball (A) from 19.6 m

-you drop another ball (B ) from 9.8 m 1 second after the first

-When do they hit the ground?

Er, Tuesday!

 

At the same time. I assume that's the answer because you said "When do they hit the ground?" rather than 'When does each hit the ground?'. Smug overload! :)

 

Next: You have one $5 mutual fund at locked in APR 5%. started in 1999. You have another identical $5 one at 5% started in 2012. What are their values in 2018?

Okay, your point being that the one started earlier has more time to constantly accelerate so will be vastly higher than the first one.

 

Next: You have one 450nm lightsource 20 ly away, another 450nm lightsource 10 ly away. Assuming HC acts like both the above examples combined, what nm will the wavelength of each lightsource be?

The further one will be vastly more redshifted than the closer one.

 

AFAICT you're confusing "father back = more compounded shift" for "farther back = more acceleration at that time"

So you're saying that the increased redshift over distance doesn't imply increased recessional velocity?

 

But here's the thing. In the accepted expansion model it's not just that the further away the galaxy, the higher redshift. The redshift is used to infer that the further away the galaxy, the faster it's moving away from us. That's the accepted interpretation of the observed redshifts.

 

So, given that the further back in time we look, the faster galaxies are supposedly moving away from us, we can state with absolute certainty that galaxies are moving away from us at a progressively slower rate the closer we look to our present moment in time. The supposed expansion is slowing down over time.

 

So how can they claim that it's speeding up?

[GAHD]

Er, Tuesday!

 

At the same time. I assume that's the answer because you said "When do they hit the ground?" rather than 'When does each hit the ground?'. Smug overload! :)

 

Okay, your point being that the one started earlier has more time to constantly accelerate so will be vastly higher than the first one.

You're catching a bit. The point was Ball (A) hits BEFORE ball (B ) because the forces affecting it have been affecting it for longer. A already has 9.8m/s of speed, because of that 1 second lead time, while (B ) is starting from rest. This is the inverse application of how HC is shown to be Growing rather than shrinking. Kinda. Close enough.

The further one will be vastly more redshifted than the closer one.

 

So you're saying that the increased redshift over distance doesn't imply increased recessional velocity?

 

But here's the thing. In the accepted expansion model it's not just that the further away the galaxy, the higher redshift. The redshift is used to infer that the further away the galaxy, the faster it's moving away from us. That's the accepted interpretation of the observed redshifts.

 

So, given that the further back in time we look, the faster galaxies are supposedly moving away from us, we can state with absolute certainty that galaxies are moving away from us at a progressively slower rate the closer we look to our present moment in time. The supposed expansion is slowing down over time.

 

So how can they claim that it's speeding up?

There is "more space" between the farther galaxies and us. Since space itself seems to be expanding uniformly, more of it means it expands faster. Maybe the Single bacteria petri dish versin of that same additive equation (total at future time)= (current amount)(1+rate)^time (same equation as the mutual fund one)

 

What that works out to is that if you have 20ly between us and 1 star, that number will expand by the same fixed ratio as the one 10ly away.

galaxies are moving away from us at a progressively slower rate the closer we look to our present moment in time

the one started earlier has more time to constantly accelerate so will be vastly higher than the first one.

Edit: and if you want to REALLY terrify yourself. Use some grade 10 algebra manipulation on that equation and find out at what future time(or total distance) the added extra amount of space become larger than the max speed of light.