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  1. #1 hello, and questions 
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    Hello, im new here and would like to join to question many things i would like to know.

    well, first of all, should numbers be considered natural, or imaginary, from the mind of man?

    2. tell me the basic struture of a black hole, and is it even possible to prove without a shadow of a doubt that they really exist since nothing can escape it.

    3.if the big crunch theory of the universe accurate in your minds, or do you think it will always expand for internity.

    4. is it not true that if you could some how able to enter a black hole without turning into spegetti, time hypothetically would slow down?


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    1.dunno

    2. alot of mass(so much that it is concentrated to a point) pulled together by gravety. Gravety grows though mass mass grows though the pull of gravety... and voila you have you're self a black hole.
    It is said that every galaxie holds a black hole in the center of the stars, holding the stars in place... basic isnt that hard.

    well ur wrong at 1 point, the back hole radiates heat (or some thing else but Im pretty shure that it was heat...) about a 1mio/10 over the complete frozen state that matter can reach. There is a formula to this (the bigger the black hole the more heat radiation)
    you would have to get very close to the back hole to mesure its heat.

    3. This is what i think the universe will crunch, if there is enough mass to pull together to form a huge black hole which will then crunch the universe.

    And if not, we might just rip appart

    4. If you know how to turn off gravety pm me, the e.vent-horizon so sayed freezes time to an almost alternaty.


    now all these questions made me wonder, if a black hole would be created that is smaller than the moon, it would theoretically dissapear, becacuse of its size. What happens with it? Does the black holes mass blow up? help


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    I read that if you were in a ship and managed to orbit just outside the black holes event horizon, time would slow way down for you because of the intense warping of spacetime at the black hole.

    Then, after an extended time, you could leave orbit, go back to your planet and find it much more advanced than when you left which could be by thousands of years.

    So, in a sense, your going forward in time. All you have to do is survive the trip.

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    thats what i thought :-D

    I also thought that their was a black hole in the center of our galaxie, that is true, right?
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  6. #5  
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    oh, if we sent a shuttle going 10 miles per sec., how long would it take to reach the nearest galaxie?

    And when will the andromada galaxie collide with our own?

    sorry if i am asking so many questions, but im curious
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  7. #6 Re: hello, and questions 
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    Quote Originally Posted by Darthskywalker699
    Hello, im new here and would like to join to question many things i would like to know.
    Hi Darth, and welcome.

    well, first of all, should numbers be considered natural, or imaginary, from the mind of man?
    You'll probably have to try to rephrase this question so we can better understand what it is that you are asking. But I interpret numbers as simply ideas that represent quantities and aid us in manipulating them.

    2. tell me the basic struture of a black hole, and is it even possible to prove without a shadow of a doubt that they really exist since nothing can escape it.
    Basically, a black hole is formed when a massive star runs out of its fuel. When this happens, there is no outward force to balance the force of gravity and the star collapses. Right after collapse, the star explodes as a supernova. If the core of the dying star is greater than roughly 3 times the mass of our sun, no force can stop the collapse (not electron degeneracy nor neutron degeneracy...). It will collapse indefinitely. So... the "basic structure" that you asked for is... picture a star much larger than our sun that collapses down to a very, very small point.

    Beyond a shadow of a doubt is pretty strong. I'm not sure if we can prove that black holes exist with absolute certainty, but there is evidence that they exist. A black hole alone would be pretty dang hard to spot, but if matter is flowing into it, the matter gets heated and emits x-rays. We can detect these x-rays from the matter flowing into the black hole as long as they are not inside the event horizon. Once we have a good candidate for a black hole based on x-ray observations, we try to find out the mass of the object. If the mass is greater than 3 solar masses, then it is almost certainly a black hole. One way to find the mass is if the black hole is in a binary system with another star. Using Kepler's third law (or maybe general relativity...) and some spectral analysis of the other star, we can get a pretty good fix on the mass of the black hole. X-ray observations of x-ray binaries has provided about a couple dozen candidates for black holes last I knew. With a little searching on the internet, you may be able to find more info on this.

    3.if the big crunch theory of the universe accurate in your minds, or do you think it will always expand for internity.
    The evidence indicates that the universe will expand forever. No big crunch. The evidence I'm referring to is that of the distant type 1a supernovae. You may want to read more on "dark energy" and the evidence for it.

    4. is it not true that if you could some how able to enter a black hole without turning into spegetti, time hypothetically would slow down?
    Yes. This is a result of Einstein's general theory of relativity. Time slows in the presence of strong gravitational fields.

    Good questions.
    Keep 'em coming.
    Cheers,
    william
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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  8. #7  
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    Quote Originally Posted by Darthskywalker699
    oh, if we sent a shuttle going 10 miles per sec., how long would it take to reach the nearest galaxie?

    And when will the andromada galaxie collide with our own?

    sorry if i am asking so many questions, but im curious
    Well... are you willing to do a little math?

    Andromeda is the nearest galaxy and is about 780 kpc (kiloparsecs) away. A kiloparsec is 1000 parsecs. A parsec is about 3.26 ly (light years). A light year is the distance light travels in a year. The speed of light is about 300,000,000 meters/second. There are about 31,536,000 seconds in a year. Velocity * time = distance. A mile is about 1.6 kilometers or 1,609 meters.

    That should be enough for you to answer your first question yourself.

    Off hand, I don't know the blueshift of Andromeda (the speed at which it is approaching the Milky Way), so I can't help with your second question at the moment....

    ~Edit:
    Just looked up this number although I won't stand behind its accuracy.
    The redshift of Andromeda is z = -0.00042 = v/c, where v is velocity and c is the speed of light. Notice the negative sign, a negative redshift is actually a blueshift (it's moving toward us). If you solve z = v/c for v, you should get v = 126 km/s. With this and the distance to Andromeda, you can answer your second question about the time until collision.
    ~end edit

    Edit #2:
    Thinking about colliding galaxies induced me to change my avatar. This is output from a smoothed particle hydrodynamics computer simulation of colliding galaxies. I created this very output myself from a SPH code called Gadget written by a physicist named Volker Springel.
    End edit

    Cheers,
    william
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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  9. #8 Re: hello, and questions 
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    Quote Originally Posted by Darthskywalker699
    Hello, im new here and would like to join to question many things i would like to know.

    well, first of all, should numbers be considered natural, or imaginary, from the mind of man?

    2. tell me the basic struture of a black hole, and is it even possible to prove without a shadow of a doubt that they really exist since nothing can escape it.

    3.if the big crunch theory of the universe accurate in your minds, or do you think it will always expand for internity.

    4. is it not true that if you could some how able to enter a black hole without turning into spegetti, time hypothetically would slow down?
    1)Numbers are man's invention to tally quantities only.
    2) a singilarity of infinite density is the current guess.
    3) Expand for eternity, it is I believe an anomaly that will exist forever.
    4) if you could take a watch into a black hole it's hands would appear to you to rotate normally time would not slow down, BUT events will.

    I could be wrong on these and would easily give way to others who may have a better [more thoroughly read] understanding.
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    Time is relative to space and velocity. It has been supported by experiment. Traveling close to the speed of light will slow a clock, even an atomic clock. Likewise, a clock outside our atmosphere, far away from any gravitational pull, will run faster than a clock on earth. Therefore, if an artificial gravitational force were created, time travel would, in theory, be possible. Am i right so far?

    By trapping light inside a photonic crystal, you can cause it to circulate. The energy of the circulating light will cause the space inside the circle to twist, causing a gravitational force.

    As the space twists, it will coil the normally linear passage of time with it, spiraling the past, present, and future together into one continuous loop.
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  11. #10  
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    Quote Originally Posted by Darthskywalker699
    Time is relative to space and velocity. It has been supported by experiment. Traveling close to the speed of light will slow a clock, even an atomic clock. Likewise, a clock outside our atmosphere, far away from any gravitational pull, will run faster than a clock on earth. Therefore, if an artificial gravitational force were created, time travel would, in theory, be possible. Am i right so far?
    Seems correct.

    By trapping light inside a photonic crystal, you can cause it to circulate. The energy of the circulating light will cause the space inside the circle to twist, causing a gravitational force.
    You lost me here. I believe mass is required to cause a gravitational force. I may have to think about this more....

    As the space twists, it will coil the normally linear passage of time with it, spiraling the past, present, and future together into one continuous loop.
    I have no idea. It might make for a good sci-fi plot line though.

    Cheers,
    william
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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  12. #11  
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    Quote Originally Posted by Darthskywalker699
    Time is relative to space and velocity. It has been supported by experiment. Traveling close to the speed of light will slow a clock, even an atomic clock. Likewise, a clock outside our atmosphere, far away from any gravitational pull, will run faster than a clock on earth. Therefore, if an artificial gravitational force were created, time travel would, in theory, be possible. Am i right so far?

    By trapping light inside a photonic crystal, you can cause it to circulate. The energy of the circulating light will cause the space inside the circle to twist, causing a gravitational force.

    As the space twists, it will coil the normally linear passage of time with it, spiraling the past, present, and future together into one continuous loop.
    Er no it does not slow the clock, if you are travelling with it you will NOT perceive a slowing down. YOu might want to go back and read it again...

    The thing you call time is nothing more than an illusion, a useful one, but an illusion, what you are suggesting is that time can run at all different speeds in all different circumstances, which is nonsense if time exists, it would be constant, I know it's a hell of a leap and harder to grasp than relativity but you will see it become standard thinking over the cpoming years, remember a clock is nothing more than a device showing a repeating sequence of numbers.
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    Quote Originally Posted by Megabrain
    Quote Originally Posted by Darthskywalker699
    Time is relative to space and velocity. It has been supported by experiment. Traveling close to the speed of light will slow a clock, even an atomic clock. Likewise, a clock outside our atmosphere, far away from any gravitational pull, will run faster than a clock on earth. Therefore, if an artificial gravitational force were created, time travel would, in theory, be possible. Am i right so far?

    By trapping light inside a photonic crystal, you can cause it to circulate. The energy of the circulating light will cause the space inside the circle to twist, causing a gravitational force.

    As the space twists, it will coil the normally linear passage of time with it, spiraling the past, present, and future together into one continuous loop.
    Er no it does not slow the clock, if you are travelling with it you will NOT perceive a slowing down. YOu might want to go back and read it again...

    The thing you call time is nothing more than an illusion, a useful one, but an illusion, what you are suggesting is that time can run at all different speeds in all different circumstances, which is nonsense if time exists, it would be constant, I know it's a hell of a leap and harder to grasp than relativity but you will see it become standard thinking over the cpoming years, remember a clock is nothing more than a device showing a repeating sequence of numbers.
    An outside observer would record the time on the moving spacecraft as moving slower than the time measured on a clock at rest relative to the outside observer. But for the chap on the spacecraft, time would appear to be moving at the regular pace. However, when the chap on the spacecraft comes back home, he might notice that everyone he once knew is now older or dead depending on how fast he was moving.

    Say Mega, I sent you a couple PMs a while ago but they are still sitting in my outbox. This indicates that you haven't received them. Check your inbox and they should appear in blue. Perhaps your inbox is full? If so, you may have to 'clean house.'

    Cheers,
    william
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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  14. #13  
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    In a way they are both natural and imaginary, they are a useful mental construct that help us represent thing that exist in nature.

    2) You may find this show interesting (if your connection is adequate):

    http://www.pbs.org/wgbh/nova/blackhole/program.html

    3) Big Crunch: so far the way some astronomist see it, it appears the universe is not only expanding but the expansion looks like its accelerating as if a force we do not understand is pushing galaxies apart like a long range anti-gravity or some giantantic vacuum effect or something. So right now the Big Crunch seams unlikely until we discover other phenomenon or understand things we dont yet understand that wount make us change our minds(or rather their minds).
    To me such a force makes sense from a philosophical perspective of forces.

    4) I think its correct in a sense, but only from your perspective.
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    1.what are god particals exactly?

    2.Ok, first, the universe is alwas expanding right? so what is the areas that the universe has not expanded to yet called? nothing?

    3.If the universe was made from the big bang theory, what was the area that the universe originated from made of? energy? can we track the radiation of the universe to find the original spot?
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  16. #15  
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    Quote Originally Posted by Darthskywalker699
    1.what are god particals exactly?
    "God particle" is the name given to the Higgs boson by Leon Lederman, a Noble Prize winning physicist at Fermilab. The Higgs boson is thought to be the source of mass and without it every particle would be massless... so theory says.

    2.Ok, first, the universe is alwas expanding right? so what is the areas that the universe has not expanded to yet called? nothing?
    I'm not sure we can ever know what it is expanding into. And I'm not sure it has a name... at least I've never heard it called anything (this may be an opportunity for you to name it... ). But the universe is space-time... it's hard to imagine what's beyond it.

    3.If the universe was made from the big bang theory, what was the area that the universe originated from made of? energy?
    I don't know. But I think energy would be a good guess.

    can we track the radiation of the universe to find the original spot?
    In short, no. The entire universe is the spot.

    Good questions,
    william
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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    What is it expanding into? why itself of course! hard to grasp?

    Suppose you travel out into space in a direct line, you will eventually end up back at the point you started, it's just that every year you delay this journey it's length gets longer! so every point on the edge of the universe is a point somewhere within in!
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  18. #17  
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    Quote Originally Posted by Megabrain
    What is it expanding into? why itself of course! hard to grasp?

    Suppose you travel out into space in a direct line, you will eventually end up back at the point you started, it's just that every year you delay this journey it's length gets longer! so every point on the edge of the universe is a point somewhere within in!
    Yes. This may be exactly what's going on.

    http://astro.uchicago.edu/home/web/o...200/nbower.htm

    Cheers,
    william
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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  19. #18  
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    I'm curious...

    Right now do we see an edge to the universe? Either a distance at which we should see galaxies if there were any but do not see them, or the edge of a close universe where one galaxy in the farthest distance of one direction is the same as a galaxy in the fartherest corner of the opposite direction?

    If not how do we know the universe is not a gazillion-gazillion-billions times larger than what the best telescopes can reach?
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  20. #19  
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    Quote Originally Posted by icewendigo
    I'm curious...

    Right now do we see an edge to the universe? Either a distance at which we should see galaxies if there were any but do not see them, or the edge of a close universe where one galaxy in the farthest distance of one direction is the same as a galaxy in the fartherest corner of the opposite direction?

    If not how do we know the universe is not a gazillion-gazillion-billions times larger than what the best telescopes can reach?
    Hi Ice,
    Here;
    http://hubblesite.org/newscenter/arc...leases/1997/25

    The problem with observing further distances is the lack of emitters of radiation. As we look at distant objects, we are looking back in time due to the finite speed of light. Before stars and galaxies could form, there wasn't much that gave off radiation... except for the cosmic background radiation left over from the big bang and the creation of the universe itself - and we see the background radiation everywhere....

    As far as seeing the same object in opposite directions (if that was what you were asking...), that is an ongoing search in astronomy. Some astronomers are searching for just such things. If they find them, this would be evidence for a certain topology of the universe and would support the concept that Megabrain suggested.

    In short, it is very difficult to see anything farther than roughly 13 billion light years because before 13 billion years ago, the universe was very young and stars and galaxies were just beginning to form - there wasn't much of anything that emitted light.

    Cheers,
    william
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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  21. #20  
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    Quote Originally Posted by icewendigo
    I'm curious...

    Right now do we see an edge to the universe? Either a distance at which we should see galaxies if there were any but do not see them, or the edge of a close universe where one galaxy in the farthest distance of one direction is the same as a galaxy in the fartherest corner of the opposite direction?

    If not how do we know the universe is not a gazillion-gazillion-billions times larger than what the best telescopes can reach?
    You can consider any point in space as an edge or a centre of the universe, back to my journey post, suppose you do fly off into the distance and we watch you through a telescope, eventually you are so far away we can no longer see you, then we turn the telescope around 180 degrees and start looking for you to 'come back' In practice you will never get back because you will always be travelling at a rate that is less than the expansion rate of the universe and never get to the 'edge' ( which is the halfway point).

    Now let's say you could have a telescope with an infinite zoom and the time it took photons to traverse the universe were zero, look into any direction far enough and you will see the earth and behind it another one and another one... like standing between two mirrors.
    BUT when you come back to reality, and add in photon transit times, the age of the earth etc then you dont see the earth in all directions, or anything else, you see what we have today.

    Has it done your head in yet?
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  22. #21  
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    "In short, it is very difficult to see anything farther than roughly 13 billion light years because before 13 billion years ago, the universe was very young and stars and galaxies were just beginning to form - there wasn't much of anything that emitted light. "
    So what you are saying is that the 13ish limit is not an optical limitation but a function of the universe's development, interesting.

    a) If the speed of light cannot be exceeded and the big bang occured around 14 billion years ago, then is the size of the universe around 14 billion lightyears radius? Which would mean that 13 billion years ago it could not have been more than about 1 billion year radius, so then if we see non-duplicate galaxies 13 billion years away in one direction and 13billion years in another then there's something wrong with this picture, right?

    b) If Gravity can curve light and slow down time, did the early gravity of a newly created and comparatively more concentrated mass of energy/matter have an effect on the speed at which the light of the big bang expand?

    c) If all the farthest(13 billionish) galaxies observed come from one side of the universe while the other side only had galaxies no further than half this distance that would tell us something about the universe(and our location), on the otherhand if the farthest galaxies could be seen in all directions and they are duplicated (ala Megabrain) that would tell us something else, and if galaxies can be seen in all directions as far back as 13 billionish without duplication this could mean something different as well.


    "Has it done your head in yet?"
    I understand the concept, I'm wondering if it has been backedup by actual observation, from what I'm reading the answer as of yet is... no.


    interesting...
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  23. #22  
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    Quote Originally Posted by icewendigo
    "In short, it is very difficult to see anything farther than roughly 13 billion light years because before 13 billion years ago, the universe was very young and stars and galaxies were just beginning to form - there wasn't much of anything that emitted light. "
    So what you are saying is that the 13ish limit is not an optical limitation but a function of the universe's development, interesting.

    a) If the speed of light cannot be exceeded and the big bang occured around 14 billion years ago, then is the size of the universe around 14 billion lightyears radius?

    b) If Gravity can curve light and slow down time, did the early gravity of a newly created and comparatively more concentrated mass of energy/matter have an effect on the speed at which the light of the big bang expand?

    c) If all the farthest(13 billionish) galaxies observed come from one side of the universe while the other side only had galaxies no further than half this distance that would tell us something about the universe(and out location), on the otherhand if the farthest galaxies could be seen in all directions and they are duplicated (ala Megabrain) that would tell us something else, and if galaxies can be seen in all directions as far back as 13 billionish without duplication this could mean something different as well.


    "Has it done your head in yet?"
    I understand the concept, I'm wondering if it has been backup by actual observation, from what I'm reading the answer is... no.


    interesting...
    As you are begining to see now it's all speculation, the observations genreally but not completely support our interpretation so the rest is up for grabs, that's a cheap way of saying, I wouldn't like to go any further cos my own understanding is not that brilliant and is receding faster than the galaxies. This aged retired brain can still grasp the odd new development but is mostly occupied elsewhere. Let me know if you find a descent explanation of the next chapter....


    Keep an open mind though, as I reckon it is all bound to change over the coming years, but by how much or little is anyone's guess.
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  24. #23  
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    Quote Originally Posted by icewendigo
    "In short, it is very difficult to see anything farther than roughly 13 billion light years because before 13 billion years ago, the universe was very young and stars and galaxies were just beginning to form - there wasn't much of anything that emitted light. "
    So what you are saying is that the 13ish limit is not an optical limitation but a function of the universe's development, interesting.

    a) If the speed of light cannot be exceeded and the big bang occured around 14 billion years ago, then is the size of the universe around 14 billion lightyears radius?
    Pretty much... yeah. The observable universe that is.... Plus there is the issue of the topology of the universe and whether it's open, closed, or flat.

    Which would mean that 13 billion years ago it could not have been more than about 1 billion year radius, so then if we see non-duplicate galaxies 13 billion years away in one direction and 13billion years in another then there's something wrong with this picture, right?
    I'm not sure I understand your question... what would be wrong with this picture?

    b) If Gravity can curve light and slow down time, did the early gravity of a newly created and comparatively more concentrated mass of energy/matter have an effect on the speed at which the light of the big bang expand?
    Are you asking if the speed of light has changed over time? I personally don't know, however I believe there are physicists seriously studying this. But... for the 'comoving' or 'inside' observer, time ticks away as normal. It's only for the outside observer that time appears to slow for the moving/gravitationally-affected object. And the inside observer wouldn't realize it until he 'went back home' to see all his friends much older. Special and general relativity stuff....

    c) If all the farthest(13 billionish) galaxies observed come from one side of the universe while the other side only had galaxies no further than half this distance that would tell us something about the universe(and our location), on the otherhand if the farthest galaxies could be seen in all directions and they are duplicated (ala Megabrain) that would tell us something else, and if galaxies can be seen in all directions as far back as 13 billionish without duplication this could mean something different as well.
    Uhhh.... well-uhhh... (clearing my throat, smacking my lips...) hmmmmm....
    Tell you what, I'll have to get back to you on this. How does this sound; I'll make a new thread in a couple o' days and summarize the universe as we know it. Sound good to you?

    A quick and dirty answer to your part 'c' is that the universe appears to be homogeneous and isotropic. And it appears there is no 'preferred' location in the universe - that is, no place is any more special than another.

    Edit;
    'Preferred' meaning, on the cosmological level everything would look the same. Of course it is preferred to be located on Earth next to a beautiful scantily-clad lady than it is to be located in the center of the sun....
    end edit

    Cheers,
    william
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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    Ah looks like you've reached the end of the universe, as I have just done a quick read up, is seems the amount of speculation past where we are at is mostly pure conjecture, ideas, and theories Damn the speed of light!
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  26. #25  
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    Quote Originally Posted by Megabrain
    Ah looks like you've reached the end of the universe, as I have just done a quick read up, is seems the amount of speculation past where we are at is mostly pure conjecture, ideas, and theories Damn the speed of light!
    Yeah... pretty much. The puzzle is still being assembled....
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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  27. #26  
    Forum Cosmic Wizard icewendigo's Avatar
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    Quote:
    Which would mean that 13 billion years ago it could not have been more than about 1 billion year radius, so then if we see non-duplicate galaxies 13 billion years away in one direction and 13billion years in another then there's something wrong with this picture, right?


    I'm not sure I understand your question... what would be wrong with this picture?
    Well if two different galaxies are placed 24 billion light years apart back 13 billion years ago, how can the universe have been 1 billion year radius then, either that or one of the galaxies has folded space or something to travel 24 billion lights years in the spand of 13 billion light years...


    summarize the universe as we know it. Sound good to you?
    THat would be great! :-D (I know about various theories but have lost track of the actual universe as we can really observe it so far)
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    On your part C question it seems that from microwave radiation which comes from every area of the sky, it appears we are at the centre of the universe, however we know our galaxy is moving away from all the others so we can't be, and this is what [I believe] essentially leads to the open flat closed models so hotly debated, I understand that wherever you are in the universe you might be deceived into thinking you are at the centre....

    If I can put it another way, think of the pattern of dots as painted on a balloon, as the ballon expands all the dots move apart so any dot can believe all the others are moving away from it, and therefore be deceived into thinking IT is at the centre. These dots are only printed on the surface of the balloon, and are therefore 2- dimensional

    Our balloon is 3 dimensional (but this does not mean you are merely filling the balloon's volume with another dimension of galaxies as this would give the balloon's universe an outer surface) we can represent the idea but we cannot imagine the 'missing' dimension that allows the universe to be infinite yet bounded. You either accept,reject, or try to come up with something that fits the data more convincingly.


    EDIT:

    How come they are 24 billion light years apart, moving away at the speed of light, then 13By agao the universe could not have been 1 Bly across - good point - I wonder that myself, I reckon it may be because light has travelled across the universe many times, maybe every 12000th galaxay we see is our own from a different perspective at a different time, so we don't recognise it but this is pure conjecture on my part and not an Idea I'd try and sell without putting a lot more work into it... Mind you it might explain why the galaxies appear to be accelerating, think of placing yourself between two almost parallel mirrors the moving them apart slowly, each successive image you see will move faster than the previous!

    What do you think William?
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  29. #28  
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    The Last tv show I saw appeared to indicate that the universe was not as uniform as the initially limited instruments had shown but that more precise instruments measured variations that showed a non-homogenous universe, not evenly distributed energy.

    The last representation of the pattern of galaxy I saw appeared to show some mishaped pattern that was not radial* and a bit counter-intuitive for a big bang result. (* no apparent center and nothing special about the edge indicating that that was the edge, nor any symetry as you might expect from a close universe where you go in one direction and end up where you start)

    I'll look into it and get back with a link if possible
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  30. #29  
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    Quote Originally Posted by icewendigo
    Quote:
    Which would mean that 13 billion years ago it could not have been more than about 1 billion year radius, so then if we see non-duplicate galaxies 13 billion years away in one direction and 13billion years in another then there's something wrong with this picture, right?


    I'm not sure I understand your question... what would be wrong with this picture?
    Well if two different galaxies are placed 24 billion light years apart back 13 billion years ago, how can the universe have been 1 billion year radius then, either that or one of the galaxies has folded space or something to travel 24 billion lights years in the spand of 13 billion light years...
    Ahah! I see now.
    This is similar to the 'horizon problem.' Er... no... that's not what you're asking....

    Oh! OK... yes.
    All matter in the universe expands with the universe in what is called the Hubble flow. So the matter created ~13 billion years ago that those galaxies are made from has been moving along with the Hubble flow for more than 13 billion years. So it would not be unheard of to see two distinct galaxies separated by up to 26 billion light years if we were to look in opposite directions. (Picture the popular 2-dimensional analogy of the inflating balloon with dots painted on it.)

    Cheers,
    william
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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    And remember, the williams, icewendigos, and megabrains in that galaxy 13 billion light years from us are viewing the Milky Way as it was 13 billion years ago (whatever it may have looked like...). We too have been moving along with the Hubble flow.

    cheers
    "... the polhode rolls without slipping on the herpolhode lying in the invariable plane."
    ~Footnote in Goldstein's Mechanics, 3rd ed. p. 202
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  32. #31  
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    will it be possible to create planets in the near future? by using gravity, or magnets of some sort? tell me more if you know
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    Quote Originally Posted by Darthskywalker699
    will it be possible to create planets in the near future? by using gravity, or magnets of some sort? tell me more if you know
    well first you need mass, lot's of mass, as to how much to build a planet, well they keep changing the definition, so to be on the safe side, 10^26 KGs shouuld be enough to get you started, so the best thing to do is buy all New York's waste for six months and you are there... No instead of dumping it in the ocean, bung it in space, I think there was an episode of Futurama which had this mass return to earth as a meteorite so watch out which orbit you give it.

    Seriously though, you can consider satellites as 'microplanets', the space station is a little larger, probably any artificial planet will start out like the station, and just be built on and on etc...
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    ok

    1. As someone said in this thread a while back, hypothetically if you were next/in a black hole(which cant be done of course), and you came back out, civilization might be thousands of years in the future right? so... if you COULD do it (which you cant), what would it look like to us back on Earth if we were to view that person in the black hole? would they move very slow or something like that?

    2. since nothing can go faster then light, does that mean that it is a 100% chance we will never view the end of the expanding universe?
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  35. #34  
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    o, and i guess i never got a chance to fully introduce myself:

    i am 15, and currently in high school
    i live in california and i wish to be an archeologist some day( and if that doesnt work out, mabye something in the field of space exploration)
    im sorry if i can not answer many questions,
    but I sure have a list of them

    please still read post before this
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  36. #35  
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    Darth; your getting quite a bit of one sided thoughts on a good many subjects. many of your questions have more than one possible explanation and some really have none.

    the speed of light is "thought", not to be achievable by any object with mass? i have a long list of things that were thought and since then have been suggested wrong.

    if nothing can exceed C, what is all this about expanding universe at faster speeds. many disagree the universe is expanding at all, much less at rates suggested.

    they say time slows down with speed. that is if you travel at 186k per second, time would stand still. i don't know but, my favorite way to explain this though; if you did travel for 10 years at this speed it may be what you left was behind is only a few hours from when you left, but you will have aged 10 years. since getting into a black hole is not logical, try some form of hibernation. say your in this state 10 years and recover or come out, you and society are both 10 years older. i have contradicted two things to simplify both ideas.

    rather than thinking of creating a planet, understand the process to how planets form. we have eight or so in our little solar system in some form of existence.

    i do hope your taking interest in Math, Science and Biology is high school and taking courses that could help you in both some Science field and a back up field. Debate and English would be helpfull as well.
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    i guess i was getting a little ahead myself, thanks for clearing things up. and yes, those subjects are interesting to me, i hope to take Ap biology next year, and adv. chemestry.

    i will try to stay in the region of scientific accuracy next time i ask a question
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  38. #37  
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    Quote Originally Posted by Darthskywalker699
    i guess i was getting a little ahead myself, thanks for clearing things up. and yes, those subjects are interesting to me, i hope to take Ap biology next year, and adv. chemestry.

    i will try to stay in the region of scientific accuracy next time i ask a question
    your questions are fine, even common. the answers as well, but they may not represent all available for consideration. my only point.

    your on the right track in school....
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