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Rustifer
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06 Feb 2019, 2:01 am

Someone please make this analogy work: Dark matter being essentially "space fat". I need this concept in my life.



naturalplastic
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06 Feb 2019, 7:21 am

So....you heard someone say the phrase "dark matter is like 'space fat'", and you liked the phrase, despite the fact that you don't understand it?

I guess that the person meant that dark matter is like "excess baggage" of the cosmos. Where as regular matter is the bare bones essential part. Or something.



Kurgan
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24 Feb 2019, 10:41 am

Dark matter is called such because it's not visible to any electromagnetic radiation, unlike regular matter. The only similarity to fat is that (almost) all the observable effect on regular matter is through gravity. The theories are still WIP, so we don't know much about it yet.


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24 Feb 2019, 11:22 pm

My theory on dark matter (and dark energy) is that it exists as part of a higher dimension than the one we currently reside in. If that theory is true, it would explain why we cannot interact directly with dark matter. When a higher dimensional object passes through a lower dimensional state, it can sometimes give indications of this event to the lower dimensional state as parts of a “ghost image”. This image is never complete enough to measure.

In a nutshell: We can sense that something is there, much like a shadow, but not the object itself.



naturalplastic
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25 Feb 2019, 8:16 pm

Einstein said that space is a "thing". Empty space is not just a void. its an actual thing. Gravity in an illusion. Gravity is actually matter warping space.

Back when the Big Bang happened both matter and space expanded outward from a single point. Beyond the outer crest of the shockwave of the big bang there was no matter. But there was also no empty space. I realize that that's hard to envision- But think of the expanding universe as being like a bubble. An expanding bubble. Outside of the bubble is non space. Just go with me on this.

Inside the bubble is space- which is expanding, and all matter.

And empty space is actually expanding faster than lightspeed carrying matter with it.

Billions of years pass. The universe gets bigger. Galaxies form, and stars and planets etc.

But the whole time matter is warping all of space, and acting as break on its expansion. Just like the earth warps the space around it causing the moon to revolve inside the circular depression earth makes in local space (the Einstein envisioned it): all matter is pulling the whole of space of the entire universe and warping it back to the singularity- even as space expands outward- kinda like a big long train with one box car with its brakes mistakenly left- doesn't stop train but adds drag to the trains forward motion).

But as space expands the ratio between space and matter gets more and more lopsided towards space and against matter. The universe get less dense with matter as it expands. So the warping of effect of matter, and there for the breaking effect of matter on space diminishes over time.

The effect of t his constant progressive loss of the breaking effect by matter on the ever increasing amount of space is that space speeds up its expansion.

So this new thing that astronomers observe (the acceleration of the rate of expansion- ie the big bang getting more bang instead of losing steam) is NOT due to added energy input to the universe from some unknown source(ie "Dark Energy"), but due to the gradual loss in the decelerating effect of matter on the expansion of space.

So there really is no actual "dark energy". What is thought of as dark energy is really the differential between the progressive loss of breaking power (gravity density of the universe exerted by matter) and the regular old manifest energy we already observe.

So there aint no actual "dark energy"

About 'dark matter"? I get back to you about that later. Lol!



AstroPi
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27 Feb 2019, 10:10 am

QuantumChemist wrote:
If that theory is true, it would explain why we cannot interact directly with dark matter. When a higher dimensional object passes through a lower dimensional state, it can sometimes give indications of this event to the lower dimensional state as parts of a “ghost image”. This image is never complete enough to measure.

That's not true. If a higher dimensional object (like 3 dimensional pin) passes through a lower dimensional object (like 2 dimensional sheet of paper), it doesn't give ghost image, it's just like a sequence of 2 dimensional objects, as real as other 2 dimensional objects and can be measured well enough.
If we talk about ghosts, here's another example. To escape from 3d room "through a wall", we would need to travel to a time when there's no wall, move to a point outside the wall, and go back to a current time. We don't need to have ghost attributes, we just need to move in a higher dimension.

naturalplastic wrote:
Einstein said that space is a "thing". Empty space is not just a void. its an actual thing.

I thought it's quite the contrary. There's no such thing as empty space. In Einstein theory, If we remove all objects, there will be no space left, space depends on objects that are in it. Space is a thing in Newton's theory.

Quote:
Gravity in an illusion.

Are you sure? I just jumped, and I returned to Earth's surface. Are you saying it didn't really happened?

Quote:
Gravity is actually matter warping space.

Nope. Gravity is [which means it is not an illusion] matter warping *spacetime*, that's the huge difference.
We have no idea what's beyond our universe, there are some hypothesis, but we have no means to falsify them, so talking about it is just fantasing.
Once again, there's no empty space, and it cannot be, not only in GTOR, but also in quantum physics.
There's no singularity, to which Universe can be warped back.
If your picture was true, the breaking effect of singularity on space at the beginning of the Universe (spacetime) would be infinite, and Big Bang would be impossible.
Dark matter and dark energy are just hypothesis that are meant to explain discrepancies between our current theories and observations. Just like aether once was. There's still no proof they exist.


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27 Feb 2019, 9:54 pm

naturalplastic wrote:
Einstein said that space is a "thing". Empty space is not just a void. its an actual thing. Gravity in an illusion. Gravity is actually matter warping space.

Back when the Big Bang happened both matter and space expanded outward from a single point. Beyond the outer crest of the shockwave of the big bang there was no matter. But there was also no empty space. I realize that that's hard to envision- But think of the expanding universe as being like a bubble. An expanding bubble. Outside of the bubble is non space. Just go with me on this.


What do you call the void that the bubble is allowed to expand within? I understand that's the theory, I don't think it sounds quite right though. Envision traveling outside the bubble when it was in its smallest state, the singularity. The singularity seems like it would have had to exist within something, a void.

naturalplastic wrote:
And empty space is actually expanding faster than lightspeed carrying matter with it.

Is that right? I thought space was expanding near the speed of light, not faster than...

How would dark matter be explained? If gravity is only the result of matter within space, then why can't the matter called dark matter be observed when in abundance, isn't it supposed to account for the majority of matter that holds our galaxies together? How could they matter, dark matter, be concentrated enough to produce noticeable gravity fields yet not have any wavelength of light emitting from it?

I had heard that some were suggesting the big bang may have never actually occurred, are they still suggesting that or has that theory 'gone with the wind'?

Also I heard something recently about singularities possibly not being real either, it never really sounded right, 'infinity small'. People say you can't use logic, but honestly, when something is fully understood, logic fits quite well. I see, you can't use logic as, 'we don't know, we're just guessing'.



naturalplastic
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28 Feb 2019, 9:17 am

AstroPi wrote:
QuantumChemist wrote:
If that theory is true, it would explain why we cannot interact directly with dark matter. When a higher dimensional object passes through a lower dimensional state, it can sometimes give indications of this event to the lower dimensional state as parts of a “ghost image”. This image is never complete enough to measure.

That's not true. If a higher dimensional object (like 3 dimensional pin) passes through a lower dimensional object (like 2 dimensional sheet of paper), it doesn't give ghost image, it's just like a sequence of 2 dimensional objects, as real as other 2 dimensional objects and can be measured well enough.
If we talk about ghosts, here's another example. To escape from 3d room "through a wall", we would need to travel to a time when there's no wall, move to a point outside the wall, and go back to a current time. We don't need to have ghost attributes, we just need to move in a higher dimension.

naturalplastic wrote:
Einstein said that space is a "thing". Empty space is not just a void. its an actual thing.

I thought it's quite the contrary. There's no such thing as empty space. In Einstein theory, If we remove all objects, there will be no space left, space depends on objects that are in it. Space is a thing in Newton's theory.

Quote:
Gravity in an illusion.

Are you sure? I just jumped, and I returned to Earth's surface. Are you saying it didn't really happened?

Quote:
Gravity is actually matter warping space.

Nope. Gravity is [which means it is not an illusion] matter warping *spacetime*, that's the huge difference.
We have no idea what's beyond our universe, there are some hypothesis, but we have no means to falsify them, so talking about it is just fantasing.
Once again, there's no empty space, and it cannot be, not only in GTOR, but also in quantum physics.
There's no singularity, to which Universe can be warped back.
If your picture was true, the breaking effect of singularity on space at the beginning of the Universe (spacetime) would be infinite, and Big Bang would be impossible.
Dark matter and dark energy are just hypothesis that are meant to explain discrepancies between our current theories and observations. Just like aether once was. There's still no proof they exist.


you have Einstein and Newton reversed.

In Newton space is what it is to us laymen. Just empty space. What objects move through. Gravity acts upon those objects.

In Einstein space is a thing. A substance. Like a trampoline. And objects made of matter are like bowling balls set upon the trampoline that warp the surface of the trampoline. And its that warping of space that causes the phenomena that we and Newton attribute to "gravity".

I didn't invent the idea that ACCORDING TO EINSTEIN "gravity is an illusion".

A human standing upon the earths surface cannot move as fast as a satellite. And you are so deep down into the "gravity well"- so deep down into well in the warped space created by the earth- and so feeble in the amount of "thrust" generated by your legs - that you can only move straight up and down a couple of feet when you jump. What we think of as gravity- and what Newton conceptualized as gravity- is really matter moving in warped space.

If instead of your leg muscles you had a Saturn V rock to propel you at 17 thousand MPH then you would go into orbit (according to Newton), or ...you would move in a straight line - but a straight line following the circle in the warp of space time made by the mass of the earth.

And if you accelerated further to 25 thousand MPH you would reach "escape velocity" (per Newton),or...you would leave the space time well created by earth altogether (per Einstein).

The moon is farther out from the earth so it only has to move about one thousand MPH to stay in orbit (or to keep moving in the well created by the mass of earth in space time at that distance).

Or that's what Einstein said. Complained to him about it. Not me. :lol: