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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

#241

Post by yllorepap »

dieppe wrote: post #90
bananabreakfast wrote: post #77

Earlier quoted context omitted.

Speaking from the pov as a former astrophysicist, that definition of redshift is not quite accurate. While we have observed the universe expanding since Edwin Hubble published his findings 90 years ago, it was in fact the Friedmann equations produced 10 years earlier that established how it would work within the context of general relativity. The Universe is expanding at every known point at the same time at the same…

> 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…

Imagine space is the surface of a balloon and you are blowing it up. Everything is in the middle of the surface, or at the centre. Everything is expanding. However we can’t appreciate this as at human scale electromagnetic and nuclear forces are dominant.

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

#242

Post by ncmncm »

ltbarcly3 wrote: post #147
ncmncm wrote: post #112

Earlier quoted context omitted.

That is the condition of cosmology. Not everyone envies it.

It's an assumption, and while you might make a reasonable argument to try to justify it, it's still an assumption. The real problem is when we cross from 'assuming these things, which we don't really have a strong reason to assume' to 'this is the way the universe is'. Without the qualifications it's extremely misleading and loses any basis it started with.

Conservation of energy can never be more than a collection of observations.

Elevate it to a principle, and you're not doing science anymore, you're doing religion. But not a fun one.

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

#243

Post by shuspect »

nighthawk648 wrote: post #182
scotty79 wrote: post #144

Earlier quoted context omitted.

I think that's exactly the idea. But if space expanded at the same rate everywhere and forever then the relationship would be linear. But it seems that further objects seem to be moving away slower than linear relationship would suggest which might mean that earlier space expanded slower.

But that doesn’t make sense. Here space expands n. Go a distance d away and now you have n d! So if we were to integrate the summation of n d!+V (velocity vector) Spaces, wouldn’t the relationship not be linear? You have an infinite amount of points between A and B. Each point expands at v. Each time point pk+1 is created you are introducing a new expansion that will then add as many expansions as are vector / dimens…

Look there: http://irfu.cea.fr/dipolerepeller

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

#244

Post by shuspect »

fennecfoxen wrote: post #102
peanutz454 wrote: post #95

Earlier quoted context omitted.

> However, if you were to change our relativistic reference frame to match a distance galaxy's As a causal science enthusiast I am lost, how does one change our relativistic reference frame?

Consider yourself. Consider a galaxy N million lightyears away that is moving away from you at high speed... Or is it really? What if it's staying perfectly still, and YOU'RE the one moving? ... How could you even tell? The principle of Relativity is that you cannot tell any difference, for the laws of physics are the same whether you are moving or the galaxy is moving. The theory of Special Relativity describes whic…

Calculate our speed against CMB. Calculate their speed agains CMB. Compare. It's easy.

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

#245

Post by roywiggins »

antman wrote: post #226
Certhas wrote: post #215

Earlier quoted context omitted.

The effect of the expansion of the universe on bound systems is far to small to be observed. Two objects 1 meter apart would move at a speed of 10^-17 m/s. Utterly unobservable. But we know space is expanding by looking at things that are super far away from us and that are not bound.

Any objects? So it's independent of mass?

It's independent of mass because it's just a little extra space being created everywhere all the time. It's not exactly a force. First, there was 1 meter between them. Now there's 1 meter and a tiny bit more. The amount of space being created is, in theory, the same everywhere. It's not a repulsive force- space is just being created.

It can actually end up making things very far away appear to move faster than light away from us, since there's a lot of space in between.

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

#246

Post by briantakita »

tsimionescu wrote: post #158
briantakita wrote: post #134

Earlier quoted context omitted.

And Plasma Physicists think that "dark matter", "dark energy", & the assertion of gravity (ignoring plasma) being the dominant force in the Univese is mathematics without physical evidence. Thus "pathological science". Irving Langmuir, discoverer of the double layer effect in plasmas & coined the term "plasma" physics, came up with the definition of "Pathological Science". He was also around during the birth of the "…

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.

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

#247

Post by nighthawk648 »

shuspect wrote: post #243
nighthawk648 wrote: post #182

Earlier quoted context omitted.

But that doesn’t make sense. Here space expands n. Go a distance d away and now you have n d! So if we were to integrate the summation of n d!+V (velocity vector) Spaces, wouldn’t the relationship not be linear? You have an infinite amount of points between A and B. Each point expands at v. Each time point pk+1 is created you are introducing a new expansion that will then add as many expansions as are vector / dimens…

Look there: http://irfu.cea.fr/dipolerepeller

I’m literally describing creating more flow lines which would cause an exponential growth in acceleration measured without really exceeding certain values.

Don’t understand the downvoted when I asked for more information and said my maths are probably wrong.

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

#248

Post by AnimalMuppet »

trhway wrote: post #139
ncmncm wrote: post #51

Earlier quoted context omitted.

Haha, it would be fun if we now have three Hubble constants.

my personal favorite value for the Hubble constant is the "c" divided by the age of Universe, it results in 70.8 km/s/Mpc, right in the middle of the other 2 established Hubble constant's values, a very nice coincidence that the objects at the Universe age distance are running away exactly with "c".

A coincidence? I think it might be an identity.

But that would mean that disputes about the value of the Hubble Constant are also disputes about the age of the universe, and vice versa.

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

#249

Post by igravious »

cygx wrote: post #191
igravious wrote: post #88

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…

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.

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

#250

Post by igravious »

BoiledCabbage wrote: post #179
igravious wrote: post #88

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…

That's the same thing that's always bothered me. That physicists never seem to discuss global time dilation - which also to my layman's eyes seems like a simpler explanation. Time everywhere is slowing down (speeding up?) Which it's why the expansion of space seems so perfect to neither accelerate nor decelerate.

Thank God there's someone else. I mean, to me, the idea is so moronically obvious (I had the idea about 15 years ago) that there must be some obvious answer why space-boffins insist that it's space that's doing the jiggling rather than time -- even though we've been told that since Einstein we ought to view the dimensions we inhabit as the spacetime (time is just another dimension) continuum.

My gut tells me that the layman's model I have of the universe precludes me from having a handle on why the idea is dumb. I console myself with the knowledge that at least I'm not so dumb that I think the idea is l33t and the whole scientific community are morons. Still, it'd be nice to have an answer.

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