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wmray
2009-Nov-04, 06:25 PM
Everything in nature seems to be made of many parts. Our bodies consist of organs and systems of organs. Earth has many parts. Our Solar system, the Milky Way, and so on. Could the universe also be part of a larger system?

EricFD
2009-Nov-04, 06:27 PM
Yes it can. Whether or not it is, remains to be seen.

Amber Robot
2009-Nov-04, 06:44 PM
Everything in nature seems to be made of many parts. Our bodies consist of organs and systems of organs. Earth has many parts. Our Solar system, the Milky Way, and so on. Could the universe also be part of a larger system?

That depends on how you define the word "universe". The word literally means 'everything', so if you found some larger complex system that we can't currently see, it would still be part of 'everything'.

cosmocrazy
2009-Nov-04, 07:00 PM
Exactly what Amber Robot stated, the term "universe" is used in different ways to different people. If you consider the observable part of the universe "our" universe then it just might be a small part in an extremely large maybe even infinite universe. If anything exists beyond the universe and not contained within this universe thus not bound by the laws of known physics then we may never know such things. Let your imagination loose cause what ever you can imagine, reality is no doubt far more amazing!

EricFD
2009-Nov-04, 07:18 PM
One of the ways that we might begin to answer that question is if the LHC is able to momentarily create a micro black hole. Let me explain.

A question that has persisted in theoretical physics is why of all the forces in nature, gravity appears to be so weak by comparison. Well, there's a theory that states that gravity isn't really weaker than say electro-magnetism or the strong and weak nuclear force--the weak nuclear force having been unified with the electromagnetic force into the electro-weak force--but only appears to be weak because it is dissipated by having to go through so many other dimensions before we experience it in our universe.

If the LHC is able to create a micro black hole, that will entail that some of the extra dimensions, of which we're unaware in our 3-dimensional universe, have been pulled in momentarily allowing gravity to be as strong as it actually is, thus creating a micro black hole. If and only if there are other dimensions as predicted by M-theory--either too small or too large to be perceive by us in our 3-dimensional universe and that are either contained within our 3-dimensional universe or in which our universe is contained, can a micro black hole be created in the LHC. If not, then the LHC and for that matter, no machine that we can create would have enough energy to create a black hole.

Creating a micro black hole in the LHC would also answer a lot of questions regarding the big bang. It would do so by replicating the conditions of the big bang by creating a singularity, which Stephen Hawking first proposed back in the 70's, I think, as the conditions under which our universe first formed. It is his contention that the big bang is the product of an infinitely dense, infinitely small (i.e. a mathematical point, so it really didn't exist, just like the singularities of black holes don't really exist as we understand existence in our universe) with an unimaginable amount of energy ready to blow up or expand. He also realized that by taking on a small part of the problem of unifying general relativity with quantum mechanics, that black holes weren't smooth at all, but where in fact fuzzy. What do I mean by fuzzy? I mean that he did this by employing the cocnept that in empty space virtual particles are continuously being created and annihilated in nanoseconds with a net energy gain of zero. He realized that if a positive mass particle and a negative mass particle (i.e. virtual particles) we're created at or near the event horizon of a black hole, that the positive mass particle would escape the gravitational power of the black hole while the negative mass particle would fall into the black hole, thus diminishing the black hole's mass, while at the same time the positive mass particle would be a net gain of energy in our universe. This net gain of energy would be measured as thermal energy and would come to be known as Hawking radiation. In the mean time, the ongoing flux of negative mass particles into the black hole would continually diminish the black hole's mass until its mass became so low that the black hole would explode or should I say, evaporate.

This is how Stephen Hawking came up with the idea that our universe at one time must have been a singularity. But his attempt to unify gravity (i.e. general relativity, the very large) with quantum mechanics (i.e the very small) needed some help from the outside. And that's where Ed Witten and M-theory comes in.

In a word or as Sallust used to put it: Verbum....if the LHC manages to produce a micro black hole, then Stephen Hawking will win the Nobel prize!

So let's see what the LHC is able to produce in the next few years. ;)

Eric

EricFD
2009-Nov-04, 07:49 PM
I apologize if I gave you more information than you wanted, wmray. Sometimes I get a little carried away when discussing these matters. And, welcome to the forum! :)

Eric

EricFD
2009-Nov-04, 07:50 PM
I apologize if I gave you more information than you wanted, wmray. Sometimes I get a little carried away when discussing these matters. And, welcome to the forum! :)

Eric

P.S. Maybe I should write a book instead! LOL ;)

Eric

George
2009-Nov-04, 10:16 PM
That depends on how you define the word "universe". The word literally means 'everything', so if you found some larger complex system that we can't currently see, it would still be part of 'everything'.It's interesting that it did not originally have such a meaning back when the Milky Way was favored as the only galaxy. The distant spiral nebulae were often called "island universes". Shapley prefered "galaxy" for each of these objects, once he gave up his battle for his view that claimed they were within or adjacent to our galaxy, and not separate galaxies. [Hubble didn't like the galaxy term, though he's the one that finally ended the debate.]

George
2009-Nov-04, 10:17 PM
Yes it can. Whether or not it is, remains to be seen.Of course, it is tough to see further than one can look. :)

EricFD
2009-Nov-04, 11:30 PM
It's interesting that it did not originally have such a meaning back when the Milky Way was favored as the only galaxy. The distant spiral nebulae were often called "island universes". Shapley prefered "galaxy" for each of these objects, once he gave up his battle for his view that claimed they were within or adjacent to our galaxy, and not separate galaxies. [Hubble didn't like the galaxy term, though he's the one that finally ended the debate.]

It was actually Immanuel Kant who first came up with the idea that not only was our galaxy, the Milky Way, an "island universe" but that some of the nebulae observed were also "island universes". William Herschel, who had read Kant's treatise on the subject was at first convinced of this idea. He even roughly got the shape of the Milky Way sort of right--his mistake being that what he perceived as vacancies or holes in the galaxy were actually clouds of cold and dense gas and dust, which was later realized by Edward Emerson Barnard (1857 - 1923) after seeing a plate processed by Williamina Paton Stevens Fleming of the Horsehead nebula. His other mistake was jumping to conclusions. When he looked at one of the nebulae and saw a planetary nebula with a white dwarf at its center, he mistakenly concluded that Kant was wrong about there being other "island universes" or galaxies, as we now call them beyond our own.

When Einstein had come out with his general theory of relativity, he was unaware that his field equations entailed that the universe had to be either expanding or contracting. At this time, Shapley's views dominated the astronomical community and it became a debate between Heber Doust Curtis (1872-1942 ) at the Lick Observatory and Shapley at Mt. Wilson observatory. In the mean time, Shapley's, then night assistant, Milton Lasalle Humason showed Shapley a plate of M31 with a Cepheid variable, the redshift of which clearly proved that the Andromeda nebula was much further than Shapley was willing to accept. Later, Humason, who was also night assistant to Edwin Hubble, showed him the same evidence and Hubble, unlike Shapley, realized the significance of what Humason had found. And, with this data that Hubble was able to prove that the Andromeda nebula was a galaxy in its own right and was much further and much larger than what Shapley believed. And what was then called the "Great Debate" was finally over.

But before then, as far as Einstein was concerned, the Milky Way was the entire universe, because the astronomers were telling him that the Milky Way was the entire universe. And from that perspective, with the Milky Way being more or less static, Einstein had to reconcile what he believed to be a static universe with his own field equations which told him that the universe was dynamic. So he introduced an extraneous term to his field equations to make the universe stand still (i.e. a kind of repulsive or anti-gravity force) which we know as the cosmological constant. As fate would have it, Hubble's later revelation, based on the redshift work of Humason and Vesto Slipher of distant galaxies, proved that the universe was expanding. As a result, Einstein realized that his original field equations were correct and the cosmological constant turned out to be what Einstein referred to at the time as the "greatest blunder of my career". The terrible irony of it all is that Einstein was right about the cosmological constant but for the wrong reasons and based on the wrong premise. Today it is generally excepted that dark energy is Einstein's cosmological constant.

People erroneously think that the progression and history of physics is this systematic progression of ideas. They don't realize just how haphazard and chancy it really is.

Eric

George
2009-Nov-05, 04:34 AM
It was actually Immanuel Kant who first came up with the idea that not only was our galaxy, the Milky Way, an "island universe" but that some of the nebulae observed were also "island universes". William Herschel, who had read Kant's treatise on the subject was at first convinced of this idea. There was swinging back and forth about these things. It fell out of favor in the early 1900's in spite of Slipher's amazing redshift results from the small 24 incher at Lowell.


When Einstein had come out with his general theory of relativity, he was unaware that his field equations entailed that the universe had to be either expanding or contracting. Yep, he ridiculed Lemaitre after receiving his letter. [He later applauded him once he realized his error.]


At this time, Shapley's views dominated the astronomical community and it became a debate between Heber Doust Curtis (1872-1942 ) at the Lick Observatory and Shapley at Mt. Wilson observatory. Yes. The "Great Debate" was overstated. Shapley simply argued for his new, enlarged Milky Way (~ 300,000 lyrs. in diameter, I think), which was supposed to have the effect that the little spirals could not be comparable. Curtis, however, was specific about them, but no slam dunk was seen.


In the mean time, Shapley's, then night assistant, Milton Lasalle Humason showed Shapley a plate of M31 with a Cepheid variable, the redshift of which clearly proved that the Andromeda nebula was much further than Shapley was willing to accept. Humason was amazing. Besides starting as a janitor at Mt. Wilson, and driving the mules to get a telescope up the mountain, shooting a mountain lion with a 22 calibre, and educated by observatory staff, he spent night after night in the cold on a platform constantly monitoring the crosshairs to collect the faint light of those distant galaxies for his old spectrograph.


Later, Humason, who was also night assistant to Edwin Hubble, showed him the same evidence and Hubble, unlike Shapley, realized the significance of what Humason had found. And, with this data that Hubble was able to prove that the Andromeda nebula was a galaxy in its own right and was much further and much larger than what Shapley believed. And what was then called the "Great Debate" was finally over. Yes, it was a double data blow. Hubble gave solid evidence for a distance-speed relation using Cepheids, and Humason quickly followed with a paper on his redshift data, which went out to 3700 km per sec. (NGC 7619).


People erroneously think that the progression and history of physics is this systematic progression of ideas. They don't realize just how haphazard and chancy it really is. Yes, there's a lot of dynamics in astronomy, and more in astronomers. :)

astromark
2009-Nov-05, 06:50 AM
We seem to have moved on from the OP and, thats fair... We have been to this question many times.
Humanities ability to perceive the whole of the universe is limited only by our imagination and, technical ability. We can not ever see it all. A very long time ago when it was a great deal smaller we might have had a chance to see it all but, as we had an issue regarding being evolved or not we are stuck with what we now have. Now we have telescopes and technology that have let us map the whole of the visible universe. We know thats not all of it. We know it is expanding at an ever accelerating rate. That some of it is receding away as we will never see it.
If there is a 'Other' universe than we can not ever do more than imagine it.
Personally I except the notion that 'This is it...' We call it 'The Universe.' Its everything. Including that what we have no knowledge of.

.

mugaliens
2009-Nov-05, 07:20 AM
Is the observable universe, the one with a current 46.5 billion light-year radius, all there is, or is there more?

According to Alan Guth, the founder of the theory of cosmic inflation, the entire universe could be between 1023 and 1026 times as large as the observable universe.

That would put the edge at 4.65e+33, or 4,650,000,000,000,000,000,000,000 billion light years distance.

Put in perspective, this theory says the observable universe is but a grain of sand on the beach of the universe.

TESLACOIL
2009-Nov-05, 09:47 AM
considering how tiny the universe is and how young it is (though its many times larger than it is old from a human perspective)

I find it very hard to believe our universe is it...all there ever was or could be

Im sure there is some kind of semi infinite sea of bubbles out there from which our universe was born...so large and old it makes our universe so utterly insignificant

It is unclear to me whether our universe will expand and fade to nothingness before it rejoins the froth....or perhaps one day i will look up at the sky to find half of it ablaze and heading my way as we just have collided with another inhabitant of the bubble verse

Interestingly statistics tell us that for every real universe we see there will be countless virtual universes created by sentient beings like us

you cant argue with that math !

(think of running a more sophisticated version of the sims on a very large computer...if u lived inside that simulation that universe would seem very real to you)

I think due to the complexity of our observed universe if we are a simulation running on an aliens pc...that alien would reside in a universe with 1 more dimension than ours as this enables a significant increase in computing power....making it possible to run our universe on a desktop pc of some 4dimensional alien teenager.

One could build a believable holodeck with today's terrestial technology....a computer the size of a skyscraper would be complex to pull off a fudged (Alan Truman Show) type of simulation

The trick would only be revealed if we sent probes to every part of the universe at once and would cause the simulation to lag or crash in a detectable way (and thats assuming the programmers were lazy and dint insert countercode to stop us detecting the true reality

EricFD
2009-Nov-05, 10:47 AM
There was swinging back and forth about these things. It fell out of favor in the early 1900's in spite of Slipher's amazing redshift results from the small 24 incher at Lowell.

Yep, he ridiculed Lemaitre after receiving his letter. [He later applauded him once he realized his error.]

Yes. The "Great Debate" was overstated. Shapley simply argued for his new, enlarged Milky Way (~ 300,000 lyrs. in diameter, I think), which was supposed to have the effect that the little spirals could not be comparable. Curtis, however, was specific about them, but no slam dunk was seen.

Humason was amazing. Besides starting as a janitor at Mt. Wilson, and driving the mules to get a telescope up the mountain, shooting a mountain lion with a 22 calibre, and educated by observatory staff, he spent night after night in the cold on a platform constantly monitoring the crosshairs to collect the faint light of those distant galaxies for his old spectrograph.

Yes, it was a double data blow. Hubble gave solid evidence for a distance-speed relation using Cepheids, and Humason quickly followed with a paper on his redshift data, which went out to 3700 km per sec. (NGC 7619).

Yes, there's a lot of dynamics in astronomy, and more in astronomers. :)

It is good to finally meet someone who knows their history on these matters, George. :)

I think this is the paper by Humason to which you have referred: THE LARGE RADIAL VELOCITY OF N. G. C. 7619 By Milton L. Humason (http://antwrp.gsfc.nasa.gov/diamond_jubilee/d_1996/hum_1929.html)

Humason, as I'm sure you know, George, later became a respected astronomer in his own right, with his own night assistant. Not bad for a guy who was a high school drop-out, a gambler and a mule team driver! ;)

Eric

George
2009-Nov-05, 01:10 PM
Im sure there is some kind of semi infinite sea of bubbles out there from which our universe was born...so large and old it makes our universe so utterly insignificant. That may be true but it is speculation at this point.


Interestingly statistics tell us that for every real universe we see there will be countless virtual universes created by sentient beings like us Statistics usually involves data but there is zero for other universes. Worse, there seems no way to obtain any such data, even in principle.

George
2009-Nov-05, 01:20 PM
It is good to finally meet someone who knows their history on these matters, George. :) Yes, I'm enjoying your historical points.


I think this is the paper by Humason to which you have referred: THE LARGE RADIAL VELOCITY OF N. G. C. 7619 By Milton L. Humason (http://antwrp.gsfc.nasa.gov/diamond_jubilee/d_1996/hum_1929.html) Nice. I just can't imagine doing 45 hours of monitoring for one plate, especially after doing over 30 hours for the first one.


Humason, as I'm sure you know, George, later became a respected astronomer in his own right, with his own night assistant. Not bad for a guy who was a high school drop-out, a gambler and a mule team driver! ;) Yes. I happen to be reading "The Day We Discovered the Universe" (Bartusiak) It's a dandy and it covers much of the little but interesting details.

EricFD
2009-Nov-05, 01:32 PM
I can't imagine doing 45 hours of monitoring for one plate, especially after doing over 30 hours for the first one either, George. I think the guys back then were a lot tougher than they are now. But, that's just my opinion. ;)

Eric