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Evidence that the key assumption made in discovery of dark energy is in error

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Re: Evidence that the key assumption made in discovery of dark energy is in error

#251

Earlier quoted context omitted.

One thing I've never understood is this. How do we tell the difference between the expansion of space and the dilation of time? Given that space and time are crudely specking intertwined (spacetime) how do we know that the effect we see -- redshifting -- is due to the spatial expansion at every known "point" and not the temporal expansion (contraction?) at every known moment? Could not the spatial size of the univers…

If this temporal expansion or contraction produces redshift in the exact same way, and you can fit it into Relativity with the appropriate math, well, six of one, half a dozen of the other — until such point as we understand some discrete mechanism underlying the operation of the universe that would be affected by the expansion of one rather than the other: minimum time steps, minimum distances, proceeding from indiv…

If this is an accurate conceptual model: https://www.esa.int/Science_Exploration/Space_Science/What_i...

I have this odd notion that the universe has stayed the same "size" (since inception) and that the parameters of the universe and the amount of matter/information has changed over time.

The impression we get (from our perspective) is that of an initial singularity, a period of hyper inflation, and then the expansion we have now.

Probably bollocks but I'd like to know why it's bollocks.

Re: Evidence that the key assumption made in discovery of dark energy is in error

#252

Good. Science is meant to be a honest search for facts: data, knowledge and wisdom. Being wrong is a feature. "I don't know" is an acceptable starting point with no shame attached. Being certain means a mountain of data to back it up. Being allowed to be wrong is a requirement. Anyone saying a scientist can't ever be wrong is likely placing oddball limits on progress that will only damage and limit the future[1]. How…

Dark matter is definitely not a rounding error [0]. There are multiple evidence for strong gravity effects where we just don't see the required matter the explain the observed phenomenons [1][2] [0] https://www.forbes.com/sites/briankoberlein/2016/09/23/rotat... [1] https://en.wikipedia.org/wiki/Bullet_Cluster#Significance_to... [2] http://cosmology.berkeley.edu/Education/CosmologyEssays/Grav... Briefly, dark matter…

I'm feeling verbose. So here we go.

Dark matter: Maybe something that we'll one day make lunch boxes out of. Maybe also a rounding error. Of some sort. In some way. You haven't got the mountain-of-data yet. A lot-of-data is a good start. This doesn't mean the missing matter isn't some super-energy infused version of something we already know about. For all we know, its simply "ordinary" matter we'd otherwise already have accounted for but seen/detected in distorted ways due to some new phenomena altering our perception. So, its real as opposed to unicorn droppings[0]. But thats only a small part of the story.

Neither dark energy or matter exist as permanent fixtures, or even as just two singulars. They are placeholders while the search for the underlying phenomena continues. The moment the unaccounted matter/energy is discovered due to phenomena A, B, C, D, E, F then those two broad individual placeholders will be replaced with more detailed names, likely in honor of someone famous or otherwise noteworthy feature of the discovery, eg shape, some quantify etc. We'll go from "dark matter" to phenomena A,B,C to something1, something2, somestate3 or whatever.

People like saying dark[1] because it sounds cool, mysterious and edgy. Its the flair for the dramatic. This is fine for awhile as long as it helps. It is a mystery. But today its a big mystery and tomorrow its on someones balance sheet. There's a lot of tomorrows to allow that to happen.

Very important note: Our knowledge is not dark. Knowledge shines light over the unknown so we can see it for what it is. That is the whole point.

[0] I'm asserting for sake of argument that unicorns aren't real. Some could say that horses with a horn were hunted to extinction and we just haven't found a sample. Thats valid as well. I'd still prefer to see some evidence like a skeleton. But for now, I'll just assume for the sake of argument they don't exist and leave the real answer as homework for the interested[2].

[1] Dark. Or transparent. Maybe we are seeing through it instead. Plastic bags in water become "unaccounted for" and can visually disappear due to transparency. Some ocean creature could easily call that bag the equivalent of what we would call dark matter. Its got water in it and around it. Ordinary matter surrounded by something they don't understand. Hydrocarbons. In explaining it we'd mention the multiple processes and atoms responsible for the formation because we know how hydrocarbons are formed. And probably not just one thing. (No I'm not suggesting dark matter is hydrocarbons but I retain the option to ironically laugh if they are a form thereof).

[2] I know an 8 year old who is highly motivated to believe they're real and with enough skills at genetic manipulation she might make it happen. And apparently they eat meat. The small-hill-of-data implies we should be careful out there.

Re: Evidence that the key assumption made in discovery of dark energy is in error

#253
post #90

Earlier quoted context omitted.

> The Universe is expanding at > every known point at the same > time at the same rate This part I don't get (I am in no way versed in astrophysics). If I am in a box, and that the box grows 10%, but that at the same time I grow 10%, what has changed? I mean, if every point in the universe expands at the same rate at the same time, what does it change? Relatively speaking, everything is the same size before and after…

So, imagine the box is filled with hydrogen gas. The space inside the box gets bigger. But protons don't, they're little packets of quarks that hold each other very powerfully. You'd have to expand space very, very, very fast to rip those quarks apart from each other, and once you did, you would have a bunch of bare quarks, not hydrogen. The quarks aren't getting bigger, since they appear to be indivisible and essent…

Thanks for this reply. I guess I now understand what people mean by "space is expanding".

If I understand correctly, space is what supports matter? Like a table supports dishes for instance (well, except that space is also "inside" particules) — and so if the table grows, the dishes don't.

I never actually even thought of what "space" means before. I thought that when we talked about space, matter was included in that (in the sense that quarks or whatever is the smallest — known? — particle take some "space" ; they're not points that can't be measured — or are they? ^^').

Anyway, it sparkled back an old interest of mine for astrophysics (well, I read one book from Hubert Reeves when I was a kid — and loved it).

Thanks again :)

(oh, as an added bonus: I guess we have no idea _why_ space is expanding, right? Because, I mean, it's a bit mind boggling...)

Edit: to be a bit clearer; I thought space was just void that "always" existed and extended indefinitely. Like, there was nothing except a small point with all the energy in the universe ; "everywhere" else a bit nothingness. Then, bim, the big bang, and matter was just booming away and making stars and planets and then galaxies and all that was just floating in this void/nothingness that was always there, never changing, still extending indefinitely. And that was why we were saying the universe was expanding — because galaxies were still speeding away from each others due to the big bang ; like an explosion with no friction perpetuing indefinitely. Now I guess I'm really confused about what "space" is...

Re: Evidence that the key assumption made in discovery of dark energy is in error

#254
post #253

Earlier quoted context omitted.

So, imagine the box is filled with hydrogen gas. The space inside the box gets bigger. But protons don't, they're little packets of quarks that hold each other very powerfully. You'd have to expand space very, very, very fast to rip those quarks apart from each other, and once you did, you would have a bunch of bare quarks, not hydrogen. The quarks aren't getting bigger, since they appear to be indivisible and essent…

Thanks for this reply. I guess I now understand what people mean by "space is expanding". If I understand correctly, space is what supports matter? Like a table supports dishes for instance (well, except that space is also "inside" particules) — and so if the table grows, the dishes don't. I never actually even thought of what "space" means before. I thought that when we talked about space, matter was included in tha…

Quarks and electrons act like they're actually points. Nobody can be totally sure, but the standard math says they are, and nobody has managed to smash them apart into something smaller or measure them as anything other than "smaller than anything we can measure." They might be small loops of energy instead (this is part of string theory), but if they are, they'd be so small it would be beyond known science to prove it. It's easier to prove something has a size (by measuring it) than to prove the opposite. Every instrument has some margin of error, so you'd never be able to exclude there being some size.

The weird thing about the Big Bang is that it's really all of space that banged, and to a first approximation, space and time as we know it didn't exist before a singularity at the beginning of the expansion. It's very possible that's wrong (there may have been a "parent universe" or a "big bounce") but to a first approximation it seems to be that there may not have been a "before" the Big Bang.

https://en.m.wikipedia.org/wiki/Expansion_of_the_universe

Re: Evidence that the key assumption made in discovery of dark energy is in error

#255
post #176

Earlier quoted context omitted.

> Physics is littered with mathematical formulations predicting new phenomenon (forces and particles). Sorry, I should have clarified: I mean I would spend all my days doubting the mathematics, rather than doubting the physical universe. If that makes sense? Of course all of mathematics can be argued to have a physical sort of root.

You cannot choose your allegiance and stick with it. The reality is that there is always various types of evidence to contend with. Chances are if you were a physicist/cosmologist you would be of the same opinion as the majority because you would be exposed to just about the same evidence.

> You cannot choose your allegiance and stick with it.

Exactly, yes. In mathematics we are also discoverers rather than inventors. I am just making the point that personality does play a role. Think of Newton's calculus vs. Leibniz's calculus.

Re: Evidence that the key assumption made in discovery of dark energy is in error

#256
post #90

Earlier quoted context omitted.

> The Universe is expanding at > every known point at the same > time at the same rate This part I don't get (I am in no way versed in astrophysics). If I am in a box, and that the box grows 10%, but that at the same time I grow 10%, what has changed? I mean, if every point in the universe expands at the same rate at the same time, what does it change? Relatively speaking, everything is the same size before and after…

So, imagine the box is filled with hydrogen gas. The space inside the box gets bigger. But protons don't, they're little packets of quarks that hold each other very powerfully. You'd have to expand space very, very, very fast to rip those quarks apart from each other, and once you did, you would have a bunch of bare quarks, not hydrogen. The quarks aren't getting bigger, since they appear to be indivisible and essent…

Space is filled with virtual particles that are constantly popping into and out of existence. As space expands, do these particles keep appearing in a given volume at the same rate? Or is the density of virtual particles declining as the volume of space increases?

Re: Evidence that the key assumption made in discovery of dark energy is in error

#257
post #191

Earlier quoted context omitted.

Relativistic frequency shifts can be understood as kinematic effects, namely orientation of photon 4-momentum relative to emitter and absorber 4-velocities. Now, spacetime geometry might be such that there exists space/time decompositions that allow us to attribute the shift to specific physical effects (relative velocity of emitter and absorber in case of special-relativistic Doppler shift, time dilation in case of…

Don't take this the wrong way. If you can't explain what's in your head in plain English in answer to a question that was asked in plain English then there's not much point in answering. I'm not getting the impression that you've answered my question, I'm getting the impression that you don't know how to answer my question.

I'll try again:

General relativity comes with a generic mechanism to compute frequency shifts. We don't need to try to figure out whether or not the effect is due to time dilation or spatial expansion, we can just do the math. But if we're lucky, we can find a way to split up space and time that allow for such intuitive interpretations. However, that's window dressing, so to speak.

All this assumes that the spacetime in question is already known, but that's how it actually happened historically: Friedmann and Lemaitre derived their solutions by imposing certain symmetries on the problem. From that, you can derive observations like redshift (Lemaitre had already done so by 1927, ie two years before Hubble published his paper), which you then compare to observation in order to fix the parameters of your model, or scrap it if it cannot accomodate observation.

As far as I'm aware, at no point in time did a physicist sit down and think "I wonder, what's the best way to incorporate redshift into my model, time dilation or spatial expansion?".

Re: Evidence that the key assumption made in discovery of dark energy is in error

#258

Earlier quoted context omitted.

They may feel that way, but the difference is that standard cosmology is a highly-successful predictive model consistent with all popular physical theories, while plasma cosmology is proposing physically unlikely phenomena that have never been observed, interpreting prehistoric art for 'observations', and fails to account for many modern observations. It's perhaps not as bad as the so-called electric universe, but it…

Good luck finding physical evidence of "dark matter" & "dark energy" then. How many more billions will need to be spent chasing windmills? We already have the equations from Oliver Heaviside & James Maxwell, btw. But have fun playing math games with no physically reproducible experiments.

Maxwell's equations won't help you understand how time works, so you can't run a successful GPS, for example. They also don't explain why stars introduce le sing effects.

Perhaps dark matter and dark energy are indeed a wrong conclusion - Sabine Hofstadter, to take a mainstream scientist, thinks so as well, and proposes some explanations that don't throw the baby out with the bath water.

Either way, physics thrives when we have observations which don't match our theories, and the only thing we can do to bring them closer is to experiment.

If a paradigm shift turns out to be necessary, then it should happen once the new paradigm is actually capable of explaining at least most (if not all) of the currently understood phenomena. For example, special relativity was perfectly in line with Newtonian mechanics, and could be used to derive the same conclusions for planet motion that Newton had painstakingly measured 400 years ago. If it hadn't been consistent with those (and with Maxwell's equations) than it would have never been accepted. And in fact, it wasn't entirely accepted until one of its more outlandish predictions - gravitational lensing - was observed experimentally, not just in general lines, but down to the actual measurement predicted by the maths.

Re: Evidence that the key assumption made in discovery of dark energy is in error

#259
post #239

Earlier quoted context omitted.

So yeah, your agenda is not to learn or discuss but to push falsified fringe theories, that were exhaustively discussed until the eighties, when better data ruled them out...

Yep. I was too young in eighties to participate in these discussions, so I can read about them only, and watch some lectures, which is not satisfying enough for my curiosity. Can we discuss something easier? Why you think that photon is immortal? Why we have rule of right hand in EM? Why we see star formations older than BB? WTF is "physical vacuum"? What is waved by gravitational waves? What is happen in linear Sagn…

Have you tried reading the papers from the period? for the rest, enroll in a physics course and try to not fall into the conceptual traps that even many that have studied and taught physics have fallen into.

Nothing is hidden, but it does take time and persistence.

Photons are not "immortal" they can decay if they have enough energy. Rule of right hand is a convention, could be left hand if you define the sign of charge differently. We don't see star formation older than BB but early universe physics is not easy to understand and there are lots of model uncertainties. Physical vacuum is what remains when no excitations are present. Gravitational waves are ripples in space itself. I don't understand what you mean by photons being formed.

You can not expect the concepts and intuitions that you formed by interacting with the macroscopic world to serve you well when thinking about the microscopic and fundamental. People used to think that you need some type of material aether that carries the waves of light. But that turned out not to be concepts that map well to reality. It took decades to learn to unthink these concepts, there is no shortcut to doing so yourself.

Re: Evidence that the key assumption made in discovery of dark energy is in error

#260

Earlier quoted context omitted.

Good luck finding physical evidence of "dark matter" & "dark energy" then. How many more billions will need to be spent chasing windmills? We already have the equations from Oliver Heaviside & James Maxwell, btw. But have fun playing math games with no physically reproducible experiments.

Maxwell's equations won't help you understand how time works, so you can't run a successful GPS, for example. They also don't explain why stars introduce le sing effects. Perhaps dark matter and dark energy are indeed a wrong conclusion - Sabine Hofstadter, to take a mainstream scientist, thinks so as well, and proposes some explanations that don't throw the baby out with the bath water. Either way, physics thrives w…

Or the lensing is explainable using standard optics...

https://arxiv.org/ftp/physics/papers/0409/0409124.pdf

Here's the EU critique:

https://www.thunderbolts.info/wp/2015/11/26/lensing-by-refra...

The thing is there were mulitiple ways of interpreting phenomona & through certain cultural choices, a certain orthodoxy was created. The problem we are seeing with modern astrophysics is that in order to explain the working of the universe using only Gravity, theories require esoteric mathematics that are by nature not observable.

Instead of putting all of our eggs in one basket, we should look at each of the foundational assertions of modern cosmology with skeptism & reevaluate our positions, particularly when there are non-observable mathematical artifacts. We have better technology & instruments now. We don't need to double down on the same religious beliefs using ever more esoteric math that is increasingly not falsifiable...

From the definition of "pathological science". Looks more like it applies to the Standard Model from these points...

* The maximum effect that is observed is produced by a causative agent of barely detectable intensity, and the magnitude of the effect is substantially independent of the intensity of the cause.

* The effect is of a magnitude that remains close to the limit of detectability, or many measurements are necessary because of the very low statistical significance of the results.

* There are claims of great accuracy.

* Fantastic theories contrary to experience are suggested.

* Criticisms are met by ad hoc excuses.

* The ratio of supporters to critics rises and then falls gradually to oblivion.

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