New Data Suggests We Don’t Live in a Void, and Supports Dark Energy

physorg.com ^ | January 28th, 2009 | Lisa Zyga

[Ernest_at_the_Beach]

Temperature fluctuations in the cosmic microwave background, among other data, are helping researchers better understand the accelerating expansion of the universe. Image credit: NASA.

(PhysOrg.com) -- An alternative proposal to dark energy in which the Earth sits near the center of a large void is undergoing scrutiny, and the results show that void models fit poorly with observed data. Nevertheless, scientists say that more research will be needed to determine if void models, dark energy, or something else can accurately explain how the universe is expanding at an accelerating rate.

Almost a decade ago, theorists proposed a void model as an alternative to the repulsive force of dark energy, an unknown force that is not well understood. According to the void model, much of the visible universe lies in a giant void that contains very little matter compared to the matter density outside the void, which is difficult to observe. The void’s low density means the gravitational “braking” force is weak in the void. This creates the illusion that the visible universe is expanding faster than it used to; however, the actual change is not a change over time, but over space.

Scientific data aside, void models have an important philosophical implication: that the Earth occupies a special place at the center of the visible universe. This contradicts the Copernican principle, which says that we should not be at a special place, and has been extended to state that the universe is homogenous. The Copernican principle has served as a pillar for modern astronomy, and if it weren’t true, then astronomers could not rely on local measurements to learn about universal properties.

[Ernest_at_the_Beach]

fyi

[Danae]

Hum, glad I had my coffee before reading this. Looks like the case for Dark Energy is so far being held up..... makes the Hadron Collider even more important.

[cripplecreek]

Further equals faster?

[Lazamataz]

Scientific data aside, void models have an important philosophical implication: that the Earth occupies a special place at the center of the visible universe.

And some people are foolish enough not to believe in God.

[FroggyTheGremlim]

I have had this conjecture for a number of years:

Suppose the Universe is not expanding at an accelerating rate. Suppose it it in reality, a giant black hole and everything is collapsing to its center.

Consider the usual model of a black hole as a rubber sheet pulled down into a space-time “cone.”

Any object at any point on this cone, eg, the earth, when looking at any other object, sees an object that is

a. Further “down” the cone,
b. “Higher up” the cone,
c. At a same axial “circle of latitude.”

Therefore, if the object is further “down” the cone, it will be travelling faster than us and appear to be moving away at an accelerating rate.

Any object “higher up” the cone will be travelling slower than us and therefore it will also appear to be moving away at an accelerating rate.

An object on the same “circle of latitude” will probably appear to be approaching us, assuming that a geodesic from us to that object would be the “circle.” But such objects would be rare cosmologically.

Perhaps “dark matter” or “the great attractor” could be attributed somehow to the gravitational attraction towards the “center” of the black hole itself.

I don’t have the math or the physics knowledge to try to prove or disprove this conjecture. But it has haunted me for a long time.

[cripplecreek]

Scientific data aside, void models have an important philosophical implication: that the Earth occupies a special place at the center of the visible universe.

Think about that for a second. No matter where you are, you're at the center of all you can see.

[js1138]

Is there an equivalent of Godwin’s Law, dealing with first mention of God on an unrelated thread?

[martin_fierro]

Darth Kitteh approves.

[cripplecreek]

I don’t have the math or the physics knowledge to try to prove or disprove this conjecture.

Not having the math is an advantage in my opinion. Physicists are too rigid anyway.

[js1138]

Not having the math is an advantage in my opinion. Physicists are too rigid anyway.

Absolutely.

There are advantages in any discussion to being able to argue that 2+2=5, for large values of 2.

[Hot Tabasco]

Just curious, does a black hole have infinite volume or is there a limit to how many planets it can suck in?

[Neoliberalnot]

Humans cause accelerated expansion of universe. Expansion credits soon to be for sale to all contributors.

[Ernest_at_the_Beach]

for large values of 2.

ROFL!

[Ernest_at_the_Beach]

Do you have a large collection of kitty pictures?

How do you keep all of your stuff organized.?

[cripplecreek]

Seems like there is a wierd theory floating around that we destroy the universe by looking at it.

[Larry Lucido]

Seems like there is a wierd theory floating around that we destroy the universe by looking at it.

Wife says I can look but don't touch.

[Ernest_at_the_Beach]

Just curious, does a black hole have infinite volume or is there a limit to how many planets it can suck in?

Well according to this:

FR Thread I posted

....Two Black holes in a tango...eject stars from the center of elliptical galaxies....I guess so that one of the black holes can't get bigger than the other one...

But there is no evidence for a Central Authority seen by the Hubble that tells a Black Hole ...You Must stop eating Now.!!!

[NormsRevenge]

Dark energy is an intriguing thing.

as to a black hole and size it can get, the sky is the limit. ;-)

[SunkenCiv]

Hubble telescope makes new discovery
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http://www.freerepublic.com/focus/f-news/1740084/posts

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http://www.freerepublic.com/focus/f-news/1347416/posts