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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

#161

Post by tsimionescu »

mathiasrw wrote: post #57

If you find things like this interesting I suggest you look on youtube for videos on the electric universe. The main take is that our current models having gravity as the main driving force shaping our universe is a misunderstanding - hence rejecting the idea of dark matter / dark energy that was "invented" to make for math for gravity work with the observations of expansion.

Unfortunately, electric universe can't explain anything, as it is not a mathematical model, and it doesn't account for the vast majority of observations successfully predicted by relativity - especially gravitational le sing and time dilation.

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

#162

Post by mikorym »

mr_mitm wrote: post #153
mikorym wrote: post #133

As a mathematician, I will inherently be biased against dark matter and dark energy (if you're calculations don't fit, then your mathematics is not suitable, so change the math before you change the physical description). What is the relationship between dark matter and dark energy, and does this have any effect on the r^2 law assumptions and the introduction of dark matter? For example, does this mean that when we t…

> if you're calculations don't fit, then your mathematics is not suitable, so change the math before you change the physical description We tried, but it doesn't fit the data nearly as well (e.g. MOND). Related xkcd: https://xkcd.com/1758/

I understand that r^2 is in many ways already the best thing to do. What I mean is that I would always scratch myself in doubt (sometimes literally) with something as simple as the area of a flat surface. I just mean that physics and mathematics are sometimes in spirit different.

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

#163

Post by mcv »

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…

This makes me wonder whether we would be able to tell the difference between the universe getting larger and matter in the universe getting smaller.

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

#164

Post by galaxyLogic »

roywiggins wrote: post #103
dieppe wrote: 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…

Well so in other words "space" is NOT expanding. It's particles of matter that are moving away from each other. Right?

So fine, but then why would we say that space is expanding, that would seem to imply we know there is some edge of space which is moving away from us, but what evidence do we have that space has such an edge?

Saying that "space is expanding" seems to hold the assumption that space has a (limited) width and height.

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

#166

Post by galaxyLogic »

Hendrikto wrote: post #97
dieppe wrote: 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…

Your interpretation of the expansion is incorrect. Basically, it looks like all points are moving away from each other over large distances. It is easier to understand in 2D: Imagine a deflated balloon with two dots drawn on it. When you inflate the balloon, its 2D surface increases, which results in the two points "moving away" from each other, without either of them actually moving. It‘s just that the surface on wh…

> looks like all points are moving away from each other ...

Do you mean all particles are moving away from each other? I think the question here was what would it mean for "points" to move? What are points anyway?

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

#167

Post by cygx »

galaxyLogic wrote: post #164
roywiggins wrote: post #103

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…

Well so in other words "space" is NOT expanding. It's particles of matter that are moving away from each other. Right? So fine, but then why would we say that space is expanding, that would seem to imply we know there is some edge of space which is moving away from us, but what evidence do we have that space has such an edge? Saying that "space is expanding" seems to hold the assumption that space has a (limited) wid…

Specific volume is increasing. If space was finite (but still without boundary - think eg surface of a sphere), so would total volume.

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

#168

Post by _Microft »

vectorEQ wrote: post #143

if you look at the magnetic soup we call matter, or maybe electromagnetism is a better term, is dark matter / dark energy / anti-matter (&anti energy??) just the same thing of a higher frequency say if matter / observables go from 0hz - 30+ Zhz.. is dark energy from 30+Zhz to ???Zhz and perhaps anti matter / energy from ???Zhz to ???????Zhz? (more question marks being higher ? :D ) or is this completely invalid and a…

Electromagnetism is only one of a number of fundamental forces [1]. See [0] if you are curious about EM radiation at different frequencies. Radio and microwaves, infrared and visible light, ultraviolet light up to x-rays and gammarays are all part of the EM spectrum.

[0] https://en.wikipedia.org/wiki/Electromagnetic_spectrum [1] https://en.wikipedia.org/wiki/Standard_Model

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

#169

Post by Certhas »

galaxyLogic wrote: post #164
roywiggins wrote: post #103

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…

Well so in other words "space" is NOT expanding. It's particles of matter that are moving away from each other. Right? So fine, but then why would we say that space is expanding, that would seem to imply we know there is some edge of space which is moving away from us, but what evidence do we have that space has such an edge? Saying that "space is expanding" seems to hold the assumption that space has a (limited) wid…

No space really is expanding. Think of it this way: You have a rubber band and you pull it apart, if you place two beads on the rubber band the distance between the beads will increase (even though they don't move relative to the rubber). But if you connect the two beads by a strong spring, then their distance will stay the same, despite space expanding. The force of the spring makes them move (relative to the rubber), counteracting the expansion of space between them.

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

#170

Post by gus_massa »

mcv wrote: post #163
dieppe wrote: 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…

This makes me wonder whether we would be able to tell the difference between the universe getting larger and matter in the universe getting smaller.

Someone has published that idea a few year ago https://news.ycombinator.com/item?id=19588996

I think it's more a mathematical trick than something deep about the universe. If you tweak the change of the universal "constants" correctly in a universe that doesn't expand, it is equivalent to a universe that expands where the "constants" don't change.

Note that there is some research about the change of the universal constant, but in most models they don't have just the rights values to make the universe look like expanding. https://en.wikipedia.org/wiki/Time-variation_of_fundamental_...

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