Dark Energy and Gravity are one, and neither are actual forces.

Rolling on from post 2, we can use modern instruments to observe gravitational lensing effects. When we look at clusters and observe lensing effects in background objects, a lens map can be obtained. You can deconvolve this map and determine a matter distribution required to give you the distortions observed. What you observe is that galaxies are observed as sharp spikes in the lens with large outer extensive tails that go way beyond the optical galaxy.

This measurement gives the total mass of the foreground object, you can then go ahead and apply the same matter luminosity comparisons and you get the same issue as Zwiky observed... large amounts of mass, not enough light.

This gives evidence that backs up both observations discussed.

I was interviewing an Ivy League physicists and asked him why the sun, due to its immense gravitational force, does not eventually pull all the planets closer to it and devour them. His explanation was that planetary orbits are all in a perfect equilibirum, and he equated it to a golf ball (a planet) twirling around the lip of the cup (the sun) ad infinitum.

This fact is mind-boggling, how such a meticulous solar equilibrium has been established to the point where nothing strays from its defined orbit. There is certainly something more to be discovered. Keep looking for answers and learn how to elaborate your ideas with already established physical laws.

And hopefully the last post

There are observations of extremes, the Bullet cluster has been observed in Optical, Ir, Xray and this allows the mapping of visible material. As it is a foreground cluster, its lensing effect has also been measured.

The bullet cluster is a colliding cluster of galaxies, and what is observed is that the observed material is significantly offset from the centre of mass of the system in that it is trailing behind. What this shows is that the observed material was affected by drag in terms of physical contact and interaction of magnetic and electric fields as the two main distributions of galaxies passed through or by each other. The total centre of mass however passed through each other and didn't slow down due to the extra fields.

We thus get a concentration of mass where there are no observed galaxies... how can this be? A model that works perfectly here is that of Dark Matter. This state naturally falls straight out of the model without any fiddling around with numbers etc. It is just what would naturally occur.

Dark matter IF it exists as Weakly Interacting Massive Particles, can match all of these observations without requiring any extra forces other than gravity.

Are we forgetting the cosmological Constant of Einstein?

Something he rejected and now many think that is the explanation for Dark Energy.

This Cosmological constant, vacuum energy, and Zero point I’m trying to understand, of course, Dark Energy also which may have something to do with all of the above.

Its interesting really that the Cosmological constant basically comes around because of integration. All that has done any mathematics knows that in pure form when you integrate you always end up with the possibility of the addition of a constant. Einstein placed it there for completeness... and he saw it as a failure. BUT yeah, turns out... well could indeed be Dark Energy

originally posted by: ErosA433
Its interesting really that the Cosmological constant basically comes around because of integration. All that has done any mathematics knows that in pure form when you integrate you always end up with the possibility of the addition of a constant. Einstein placed it there for completeness... and he saw it as a failure. BUT yeah, turns out... well could indeed be Dark Energy

Isn’t that something, Einstein rejected his own theory in his time and was mocked, I believe.

He wanted or he saw beauty, synchrony, and order and as you say—completeness and he, in the end, may have been right.

He didn’t think God played dice but didn’t realize God is the dice, too!


Btw, thanks for your informative posts. I'm learning.

Actually according to a new paper, dark matter and dark energy are unified into a "negative mass" or negative gravity. According to the report, if you were able to push a negative mass it would accelerate back toward you.

phys.org...

Interesting item, published today.

a reply to: ErosA433
Wow that was an impressive reply. I asked for it.
I have to admit that I am ignorant of a lot of work Zwicky has done on galactic cluster movements. I will have to read up on it more when I get time and until then I don't feel I can adequately reply, you got me. Perhaps I can find the answers I am looking for if I look a bit harder.
Thank you for your time an effort.

a reply to: ausername

Negative mass? Interesting. It would not have property of forming atoms or other structure. Would disperse to a point of being of no use. If you could collect and launch into black hole would be interesting.

originally posted by: JohanikaDeVries
I don't have the connection for the physics knowledge I need now, so I can not write the equations.

Since there's no math, and the analogy is so rough, there's very little to evaluate with your idea.

originally posted by: ErosA433
Is a vast misquoting of what the article says, or maybe the content is wrong. Scientists have never expected to know what the universe is doing... the cosmological models always gave 3 options, open, flat, closed. They were always the options and expectation would be, if all is going to play nice and not cause any issues would be flat or closed.

Open is where the universe expands and continues to expand and begin accelerating
Flat is where the universe expands and eventually stops in a stable configuration
Closed is where the universe expands and eventually stops and contracts.

There was no preference, though most people would say, as i said above, that flat or closed appear more 'natural' but, the universe doesn't care what we think to be normal or not.

I'm sure you know I think you're a valuable contributor on ATS giving accurate insights on science issues like these, and I generally agree with 99.99% of what you say, including all the excellent posts you've made to this thread. The above post is generally accurate too, but I find somewhat of a contradiction here: "Scientists have never expected to know what the universe is doing"...seems to be in contradiction with "They were always the options and expectation would be, if all is going to play nice and not cause any issues would be flat or closed."

So to me it reads like, they didn't have expectations, but they had expectations. Contradiction, right? Or am I mis-reading? Yes there was a third option of open, but nobody expected it. I don't think the article is misquoted or wrong, so your statement that flat or closed was expected is closer to the truth than "Scientists have never expected to know what the universe is doing" in this particular case.They probably shouldn't have had such strong expectations, but I have little doubt that they did even though they were aware of the open model possibility. This expectation is worded even more strongly in a part of the article not quoted in the prior post:

science.nasa.gov...

In the early 1990s, one thing was fairly certain about the expansion of the universe. It might have enough energy density to stop its expansion and recollapse, it might have so little energy density that it would never stop expanding, but gravity was certain to slow the expansion as time went on. Granted, the slowing had not been observed, but, theoretically, the universe had to slow. The universe is full of matter and the attractive force of gravity pulls all matter together.

I think that pretty much nails down which of your two apparently contradicting statements is right. So yes the open model was considered a possibility, but such a remote possibility that as far as I know, the article is right that nobody expected it. And perhaps literally nobody which would be unusual in science because there are always dissenters it seems, but I never found the lone dissenter(s) who said "I told you so" when the open model was found to be what was observed. Also, I read articles by the scientists making the 1998 discovery about how distressed they were by the accelerating expansion data which had to be wrong because nobody expected it, so they had to check, re-check, and re-check the data again because they knew nobody was expecting what the actual data showed.

oh you are totally right, there is indeed a contradiction there

its what id say is often an issue with science is a want to find 'naturalness' or order to all things.

Like in the universe in this case, the universe exists, we exist to interpret it, and that should be a random selection in it's existence. We would naturally want to then build a model that has some structure we can understand or relate to. So with life comes death and so, the way it might be easier to imagine is that the universe expands, and then collapses. or expands and eventually stops... so those get a bit of a bias, conscious or unconscious



so absolutely bang on and a great point.

originally posted by: cooperton
I was interviewing an Ivy League physicists and asked him why the sun, due to its immense gravitational force, does not eventually pull all the planets closer to it and devour them. His explanation was that planetary orbits are all in a perfect equilibirum, and he equated it to a golf ball (a planet) twirling around the lip of the cup (the sun) ad infinitum.

This fact is mind-boggling, how such a meticulous solar equilibrium has been established to the point where nothing strays from its defined orbit. There is certainly something more to be discovered. Keep looking for answers and learn how to elaborate your ideas with already established physical laws.

When did you conduct this interview? There's a lot more to the story. Nobody was there to see what happened, but we have pretty good computers now that can run more complex models than ever before, and what those simulations seem to suggest is that what we see in our solar system are the "leftovers" that didn't either get pulled into the sun, nor flung out of the solar system. If those simulations are anywhere near correct, our solar system probably started out with many more planetesimals, then "proto-planets" than we have now, and the gravitational interactions were somewhat chaotic at times and not all orbits were stable. Some of the proto-planets likely collided, like Theia colliding with the earth which is thought to have formed the moon.

Some proto-planets probably did end up going into the sun, and some almost certainly went the opposite way and got flung out of the solar system. The planets that didn't get flung out or spiral into the sun are what's left, so that's why I called them "leftovers". When you look at it that way it doesn't seem to magical that the remaining planets ended up this way, compared to the way you put it where you don't mention all the other proto-planets that didn't end up in such stable orbits. Just because you can't see them, doesn't mean they aren't there flying away from our solar system, or with others ending up in the sun. The sample you're looking at is biased to only show the stable remainder, it's not the full data set, and I doubt any cosmology boffin today thinks all the planets that formed ended up in stable orbits. Maybe if you did that interview 30 years ago some didn't know any better.

Here's one such simulation showing how proto-planets interact gravitationally where one can give angular momentum to another, flinging one out while the other falls into the sun. You can also see a proto-planet collision.



This simulation was posted 6 years later and shows much more detail, and shows many, many objects being flung out of the solar system so to the extent your post implies solar system formation is not a chaotic mess and that all orbits are stable, the science and the simulations show otherwise, that we only ended up with some stable orbits after a big mess of unstable orbits was cleared out. All following the laws of physics, of course.

originally posted by: Devino
a reply to: ErosA433
Wow that was an impressive reply. I asked for it.
I have to admit that I am ignorant of a lot of work Zwicky has done on galactic cluster movements. I will have to read up on it more when I get time and until then I don't feel I can adequately reply, you got me. Perhaps I can find the answers I am looking for if I look a bit harder.
Thank you for your time an effort.

No problem at all, apologies if i came across a little snarky. Iv often just found it to be a little bit annoying when people post up the old trope of "Its just a fudge factor" while that wasn't directly your accusation, it came close enough haha. As you see, actually the evidence for it is quite compelling and covers a wide range of observations. It has also undergone a long long period of study.

Actually to answer another question in regard to costs. It is hard to estimate as the studies in an astronomical sense might appear expensive but the instruments are not built simply for one measurement or study. SO if we ignore those, and focus on only the ramp up of attempted direct detection of Weakly Interacting Massive Particles, the cost is actually lower than you might think on the grand scheme of things. Example, for astronomy is hubble, cumulative costs being around 10billion US, for about 20 years of its operation... thats 500million a year... its actually not though, since the instrument and launch cost 4.7billion... so really thats 5.3 billion for 20 years use, or 250ish million US per year... not all of those hours went into dark matter though, hence the issue knowing the cost of the data for the specific research.

SO if you look at the experiment I worked on building, I think the grant for it was about 10 million CAD, which included everything, equipment, RnD, Post-doc and engineers salaries, travel budget, computing resources etc. This built the one of the largest dark matter experiments to date using Liquid Argon. It took about 7 years to complete, and has a 3 year run plan, initially.

10 million CAD sounds expensive, but when you look at things governments spend money on, you find that, its actually not a crazy amount. In truth that figure is also a little bit of an estimate since the grant wasn't for a single experiment, it was a larger amount for a group of experiments before being divvied up. The other part that people always appear to forget when it comes to science funding is that the money goes mostly back into the economy, and not to the scientists. People think that scientists are wealthy beyond their wildest dreams and all drive fast cars and buy several expensive houses. Truth is, If i wanted to make money... id leave physics. I can easily pull about double my current salary if i tried, by going into another sector.

SO money from those grants, at least in the case of our experiment went to lots of local machine shops etc in order to fabricate equipment, not into our pockets. Which is largely unlike other sectors where grants largely go into things like... corporate benefits which ultimately end up being used to stock up a CEO or executives salary at the expense of the worker.

Short version is that, blue skies research is typically quite cheap on the grand scheme of things, and its about time governments funded it well, rather than only thinking of lining the pockets of big business.

a reply to: Arbitrageur

Even though one day in the very distant future the sun will gobble up the planets when it expands

a reply to: JohanikaDeVries

I don't understand gravity. I don't need to.

I just daily pray it doesn't fail..........I'm afraid of heights!

a reply to: TonyS

If the universe stopped spinning (four dimensional equivalent to rotation) gravity would fail and expansion would be replaced by contraction.