Do We Live In a Giant Cosmic Bubble? 344
Khemisty writes "Earth may be trapped in an abnormal bubble of space-time that is particularly void of matter. Scientists say this condition could account for the apparent acceleration of the universe's expansion, for which dark energy currently is the leading explanation.
Until now, there has been no good way to choose between dark energy or the void explanation, but a new study outlines a potential test of the bubble scenario.
If we were in an unusually sparse area of the universe, then things could look farther away than they really are and there would be no need to rely on dark energy as an explanation for certain astronomical observations.
'If we lived in a very large under-density, then the space-time itself wouldn't be accelerating,' said researcher Timothy Clifton of Oxford University in England. 'It would just be that the observations, if interpreted in the usual way, would look like they were.'"
I always wondered... (Score:5, Interesting)
If this was why the galaxies appear to rotate to quickly at the edges.
Would the greater density at the galactic cores cause time to go slower and effect the apparent speed as observed from the exterier of the system?
Re:Being special (Score:5, Interesting)
Except if such specialties make our sentient life possible (or much more probable).
You mean like... (Score:3, Interesting)
a 3 million sun heavy black hole...like the one in the center of many galaxies including our own?
Re:Being special (Score:5, Interesting)
If you get far enough away from this universe, and I'm talking 'Douglas Adams' far, this universe would appear to be perfectly uniform. However, the closer your observation point becomes, the easier it is to distinguish the clumps, bumps, peaks, valleys, troughs, etc. in the density. At a very close, human-type scale, the density changes are very easy to spot. How dense is the space between the Earth and the Moon as compared to the Earth itself?
Re:Occam's Razor? (Score:5, Interesting)
My favorite alternative is that we need someone to do to Einstein what Einstein did to Newton; that just like Newton's laws are near-perfect and beautiful at reasonable speeds, maybe there's something that happens at cosmically grand distances, masses, or propagation delays for Gravity that we're going to have to be awfully clever to ever hope to reliably detect.
Dark Matter and Dark Energy both felt like big hacks to me.
But, I am by no means a scientist, just an interest layman who hasn't done enough reading.
I concur and have the following questions. (Score:4, Interesting)
I like this theory. My questions are, if our known universe is a bubble/globule of matter floating in a larger void...
Re:Being special (Score:5, Interesting)
I think we really need to restructure our underlying philosophy of what existence is. I've been chewing on this concept for years:
This "universe" isn't infinite. It's a 4 dimensional object, with a large but quantifiable amount of mass/energy, and this mass/energy has permutations across x, y, z and t. You see a 3 dimensional object with dimensions x, y, z moving through t, but observed from outside the t dimension, it's a 4 dimensional object.
The big bang, the singularity, is significant because at the moment that the mass/energy of the universe is in the singular state, it is identical to all the other universes. It is at this point that it "connects" to all the other universes, like petals connecting together to make a flower.
Questions of religion, spirituality and what it means to be human start getting in your way once you start looking at things this way. Am I an aspect of this object that is my universe, or am I some sort of traveler within this object that is a universe?
I think there's a good possibility that the missing matter and forces we hypothesize to be acting upon our universe are actually other universes influencing our own, like petals on a flower bumping into each other. And, assuming that we are "souls traveling within the universe" as opposed to "4 dimensional objects that are aspects of the universe", it isn't outside the bounds of reason to imagine that we might one day be able to map the shape of these universes and achieve "time travel" by moving to other universes.
I expect that we will eventually find the concept of the "infinite universe" to be a false path, and that we will achieve great breakthroughs when we find a framework that doesn't rely upon its existence.
Re:Occam's Razor? (Score:2, Interesting)
"My favorite alternative is that we need someone to do to Einstein what Einstein did to Newton; that just like Newton's laws are near-perfect and beautiful at reasonable speeds, maybe there's something that happens at cosmically grand distances, masses, or propagation delays for Gravity that we're going to have to be awfully clever to ever hope to reliably detect."
Screw that - the reason Einstein needs to go down can be summed up in one word:
Starships.
(and not the lameass rock band, either)
Re:Bubble? (Score:5, Interesting)
Re:Occam's Razor? (Score:3, Interesting)
Sparse bubble more special than "normal" matter? (Score:4, Interesting)
As mentioned in the article:
One problem with the void idea, though, is that it negates a principle that has reined in astronomy for more than 450 years: namely, that our place in the universe isn't special. ... "This idea that we live in a void would really be a statement that we live in a special place,"
Hold on a second...
Current thinking is that 74 percent of the universe could be made up of this exotic dark energy, with another 21 percent being dark matter, and normal matter comprising the remaining 5 percent.
So, being part of the 5 percent of "normal" matter isn't living in a "special place"?
Just admit you don't know. (Score:2, Interesting)
As for the content of this story, I mean, come on. I think it is silly that scientist continually feel the need to come up with a "reasons" which bridge the gaps between observable and more importantly, testable and reproducible conclusions. Dark Matter. UH-huh. Oh, no, wait.. wait.. space-time bubble! Yeah, that's it! How about we decide to leave the unknowns as unknowns and instead of spending time and resources coming up with viable possibilities to explain the unknowns, we spend that time discerning the actual, factual answers.
If we keep coming up with "viable possibilities" then all we are really doing is
The heart of my point.. the same thing happening to cosmology happened to the theory of electricity a long time ago.. and now we have generations of people who were taught to understand electricity in way that does not promote it's true nature. Same with light. How about instead of teaching our children something that is inherently wrong, we teach them what we do know, and admit that there are aspects we don't understand. At least then they (we) might have a chance to develop useful mindsets and contribute to respective solutions and explanations rather than taking away from them by filling people's head with misleading information.
Re:The anthropic cop-out (Score:2, Interesting)
Philosophy is just jealous of its little brother science that went on to bigger and better things while philosophy is still trying to shake off post-modernism.
Science = Planes, trains and automobiles, semiconductors and superconductors, quantum mechanics and nuclear fusion...
Philosophy = Thousands of years spinning its wheels and still no consensus of what truth is and still dealing with misleading concepts like "qualia".
I think many philosophers are bitter because they aren't really the center of attention anymore. Philosophers these days seem more interested in pooh-poohing everyone else's lack of subtlety. Unfortunately, after people become so entrenched in technology, questioning the philosophical basis behind such technology seems absurd and reeks of solipsism.
Btw, I'm still waiting for someone to explain the unreasonable effectiveness of mathematics in describing nature.
Connecting ideas (Score:2, Interesting)
It can sounds weird, but I've already thought about that. From relativity theories and connecting it to the third law of motion, action-reaction, and energy conservation laws.
Imagine the following: a huge amount of mass and/or energy increases the density of space-time, creating acceleration known to us as gravity. In fact a bend in space-time tissue attracting everything around, like a curved depression in a surface.
If we think in the conservation of energy in a system (and think the close universe as a closed system), this increase of density at some point should cause a deacrease somewhere, so we keep the total amount of space-time constant for this close system. Think of it as a compensation. Think on this as we strech a bubble gum, some areas get thiker, others thinner, but the total amount of gum is the same.
As increase of space-time density creates attraction (gravity), a decrease should create repulsion ("anti-gravity").
Thinking again into the curved depression, close to matter and energy, far from it we should find peaks in the surface, repelling matter.
In fact, I believe we can find these gravity bubbles surrounding some more gravitational systems, like galaxies, blackholes, and solar systems.
And more! Think about huge amounts of mass moving, like planets, stars and blackholes. The movement os these bodies would create a space-time wave effect surrounding them, which we could connect to the Doppler effect later, for even more weird effects. We already know about these interference from spinning planets, stars and blackholes.
Which make thinks even more diffcult, because relatvity should need to be adapted to include these interferences of anty-gravity if they become true, specially for interstelar long distances.
How old is the Universe? (Score:2, Interesting)
So if time moves faster, how long does it take to cross one? Is it bigger inside than outside?
The alleged cop-out that is Wikipedia (Score:3, Interesting)
To make even more of an impact, though, try linking to a reputable source.
By linking to a Wikipedia article, I linked to all the reliable sources that the Wikipedia article cited. Do you complain that they are not reliable sources, or do you claim that the Wikipedia article misrepresents the sources?