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chaloobi
SFN Regular
1620 Posts |
 Posted - 10/03/2008 : 07:31:27 [Permalink]
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Originally posted by bngbuck
BPS and great dane 80 (if you're "lurking").....
Wiki defines space thus...| Space is the extent within which matter is physically extended and objects and events have positions relative to one another[1]. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of the boundless four-dimensional continuum known as spacetime. The concept of space is considered to be of fundamental importance to an understanding of the universe although disagreement continues between philosophers over whether it is itself an entity, a relationship between entities, or part of a conceptual framework. |
What is your understanding of the meaning of the word "space", as used in the context of particle physics, and/or astrophysics?
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SciAm's got an interesting article about current theories of quantum gravity which talks about space and time itself being divided into a mesh of densely packed individual, descreet pieces analagous to how matter is divided into atoms. Those pieces would represent the smallest division of distance possible in the universe, so that old paradox of if you travel halfway to a particular destination with every step you will never get there is physically false. You can only get down to traveling the minimum quantum distance and never smaller. If true then space is looking more and more like a material than an empty repository for matter. Not sure what's between those pieces of space and time.... |
-Chaloobi
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Simon
SFN Regular
USA
1992 Posts |
Posted - 10/03/2008 : 08:27:48 [Permalink]
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| Not sure what's between those pieces of space and time.... |
Turtles... |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 10/03/2008 : 09:56:44 [Permalink]
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I define space as a yet to be fully understood volume/area containing energy. By all observations it does appear that space is growing from the inside out (EDIT:though not from a central point). We will likely never be able to tell if it is also growing from the outside.
These are not my ideas but the ones most current to the community, as I have understood them. I try to keep up with the latest as best I can. If I am mistaken please do correct me. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
| Edited by - BigPapaSmurf on 10/03/2008 09:58:05 |
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bngbuck
SFN Addict
USA
2437 Posts |
Posted - 10/03/2008 : 10:03:14 [Permalink]
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Dave.....
What is your understanding of the entity labelled by the word "space" - again, in the contexts of particle physics and astrophysics? |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 10/03/2008 : 10:16:34 [Permalink]
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In my mind I imagine space as the more standard rubber sheet concept which exists on all planes simultaneously, dark matter as a liquid dispersed on the sheet and matter as particles suspended in the liquid.
As the suspended matter begins collecting into objects large enough to make big dents in the rubber sheet the liquid begins filling the holes and losing its even distribution, the added mass of the liquid makes the dents even larger and brings the particles closer together. At this point in time nearly all of the liquid and particles have collected into a 3d matrix of streams, where the streams meet, you get superclusters and huge collections of darkmatter liquid.
In my mind, what I added to the rubber sheet was a positive pressure on its 'underside', while the DM liquid is evenly distributed it negates the positive pressure from below. When the liquid has collected into lakes however this leaves 'dry' areas which no longer can counter the positive pressure, which leads to the stretching effect of void space/Dark Energy.
The Dark Flow is very interesting I can't wait to get more data. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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chaloobi
SFN Regular
1620 Posts |
Posted - 10/03/2008 : 10:30:08 [Permalink]
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Originally posted by Simon
| Not sure what's between those pieces of space and time.... |
Turtles...
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Hey, SciAm's got the article on line for free. Here's the link:
http://www.sciam.com/article.cfm?id=big-bang-or-big-bounce
Big Bang or Big Bounce?: New Theory on the Universe's Birth
Our universe may have started not with a big bang but with a big bounce—an implosion that triggered an explosion, all driven by exotic quantum-gravitational effects
Key Concepts
Einstein's general theory of relativity says that the universe began with the big bang singularity, a moment when all the matter we see was concentrated at a single point of infinite density. But the theory does not capture the fine, quantum structure of spacetime, which limits how tightly matter can be concentrated and how strong gravity can become. To figure out what really happened, physicists need a quantum theory of gravity.
According to one candidate for such a theory, loop quantum gravity, space is subdivided into “atoms” of volume and has a finite capacity to store matter and energy, thereby preventing true singularities from existing.
If so, time may have extended before the bang. The prebang universe may have undergone a catastrophic implosion that reached a point of maximum density and then reversed. In short, a big crunch may have led to a big bounce and then to the big bang. |
Interesting, it's suggesting time did not start with the Big Bang but that it never stopped between now and the prior expansion period. And the atoms of volume with finite storage capacity ... sweet. Intersting read.
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-Chaloobi
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| Edited by - chaloobi on 10/03/2008 10:30:41 |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 10/03/2008 : 10:39:54 [Permalink]
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| It makes more sense than a universe just starting and existing by itself, however unless we borrowed m/e from a previous verse, that must have been one hell of a big collapsing object. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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Simon
SFN Regular
USA
1992 Posts |
Posted - 10/03/2008 : 10:46:47 [Permalink]
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| Interesting stuff; thanks. |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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chaloobi
SFN Regular
1620 Posts |
Posted - 10/03/2008 : 10:48:35 [Permalink]
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Originally posted by BigPapaSmurf
It makes more sense than a universe just starting and existing by itself, however unless we borrowed m/e from a previous verse, that must have been one hell of a big collapsing object.
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It doesn't solve that fundamental conundrum. The universe still had to start at some point. Right? I can't wrap my mind around it if it didn't. 
Anyway, this just feeds into my own cosmological theory, that the universe is a mechanism, perhaps a calculating machine, operated by the Titans for some arcane purpose. They run it over and over again, trial after trial, tweeking the starting conditions and examining the results, then smooshing it up and running it again. This has all happened before, more times than imaginable, a little bit different each time. Boing boing boing.  |
-Chaloobi
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Ricky
SFN Die Hard
USA
4907 Posts |
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bngbuck
SFN Addict
USA
2437 Posts |
Posted - 10/03/2008 : 14:55:33 [Permalink]
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Ricky......
| That has been described as one of the great open questions in physics. What exactly is "space" and what is it made of? |
.....yeah, that's kind of why I asked it! I do get a different perspective from each answer that brave souls offer, tho'!
Do you have a visualization, conceptualization, or ideation Ricky? I'm doing my damndest to form one, but it's not easy! I don't think in mathematics, and maybe my question is not answerable in English. May very well be true, but it is damn frustrating!
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Dark Flow - Out there Beyond the Horizon
