first of all, what i'm about to discuss is pseudo science, but i'm interesting in listening to the opinion of people regarding the philosophical implication.

anyhow, the horizon, or the edge, or the boundary of the universe is unreachable.

there are two simple obstacles reaching the horizon.

one, the expansion of the universe is accelerating faster than speed of light, even in a vacuum. since we will never be able to reach the finite speed's light, it's impossible to reach the horizon.

two, in a thought experiment, Einstein demonstrated in his general of relativity, that if you were headed straight in any one direction infinitely, you will end up back to the same location due to the curvature of spacetime.

so it's pointless to think beyond the horizon of our spatial universe. however as any science fiction enthusiasts, you want to overcome the human limitation; therefore, to exceed the universal boundary.

the question is what do you think is beyond the horizon? will they be multiverse? will there be two types of universal structure? a stack up universe or bubble universe or both?

a stack up universe is a small universe inside a bigger of a larger universe, and a bubble universe is a universe that float parallel to hundred of other universes?

in order to demonstrate what i meant, here is a picture i envision.

stack up universe

note: the blue spherical shape can said to be the pathway to the next dimension of a higher, larger universe, colored in blue. (ie, a black hole at the singularity)


bubble universe


note: in this universe, any one of the black bubble is our universe, and each bubble floating in the emptiness of space, perhaps regulate by different laws of physics or the same. we don't know.


which one fit your imagination?

I'll not attempt to refute your points, since I can see why pointless imaginative unscientific philosophical musing can be fun.

But one thing I need to correct what you've said is that the universe is not ACCELERATING faster than the speed of light.
The speed of light in vacuum is a constant no matter the frame of reference and can never be accelerating or decelerating. The universe on the other hand is expanding at an accelerating rate, where each point in space is expanding outwards in all dimensions as time evolves.

There is an "event-horizon" similar to that of a black hole where the region of our universe beyond a certain spherical radius around our point of reference is expanding away from us at a speed at the speed of light, and by extrapolation of the theory, the space beyond that imaginary spherical surface is thus travelling away at faster than the speed of light, and time dilation effects wrt to our POV becomes significant approaching that point. Hawkings have also shown that that that region, from our POV it would appear that it is radiating Hawking radiation similar to the surface of a black hole. Very strange indeed.

talking about this does seem like something a science fiction author would try to ask lol. Maybe beyond this Universal boundary, there is nothing.. just Space. No multiverses or no parallel universes, just this one. As we expand we take up the empty space that is beyond our universal boundary. maybe i have a lack of imagination and i am talking out my @$$, but thinking outside the box with the little information we know about the universe limits us to our imagination. Maybe if i smoked so much THC, then i could come up with a fictional answer that will stress the mind :P

i would like to thank you for the straightforward and intelligent reply.

anyhow, i'll like to correct myself and reinstated what i meant by the expansion of the universe is accelerating faster than the speed of light.

you're absolutely correct that the speed of light is a constant and finite by nature, which is about 2.999 x 10^8 (or approximately 300,000,000 m/s or 300,000 km/s).

now first, we must agree on these fundamental conditions about the nature of light's speed:

1. any material matter with a rest mass will not transmit faster than light's speed.

2. in a inertia reference frame (or simply "rest frame"), no objects can be accelerating faster than the speed of light in a vacuum.

3. because photon is massless (no rest mass) and is an electromagnetic energy, information can be transferred and communicated at the speed of light. for example, electric pulse and satellite signal communicated at light speed.

but here's why those fundamental conditions don't work with the universal law of spacetime.

1. space property is not material matter. it is just emptiness or void substance, which means space with rest mass absolutely make no sense.

2. in space, all objects are moving away from each other. this means no objects are at rest frame or frame of reference, so space does not exactly try to "race" with the speed of light begins at its rest frame. instead, everything is moving away caused by space expanding in all directions, like you mentioned.

3. space is not an electromagnetic energy, thus no information is being communicated and exclude from any energy substances. in fact, space is being created.

therefore, the fundamental law of light's speed does not applied to the acceleration of the universe.


but okay, i'll explain and address in detail.

initially the inflationary period of the big bang caused the universe to expand rapidly, and the wavelength of light must be sketching by this expansion, thus by the time, light od distant objects reached us, all we see is the long electromagnetic spectrum or visible light in a set of color shifted.

this was discovered by the Hubble telescope that we now know the universe is expanding by observing the color shifted of distant celestial objects.

Hubble, who is a telescope astronomer, introduced this discovery with his calculated variable, called the Hubble constant to measure the expanding universe speed.

consequently, when astronomers measured the distance of faraway galaxies, quasars, and supernovas, they used Hubble's law with technical method from the Doppler effect.

this Doppler effect allowed astronomers to observe the electromagnetic wavelength shifting toward a particular color region of the optical spectrum.



when considering this effect, the color shifted to red corresponding to a lower frequency range, and color shifted to purple corresponding to a higher frequency range.

in other words, objects that are farther away will be shifting toward red and closer objects toward purple on the optical spectrum.

realistically speaking, most objects are shifting toward blue, yellow, and red since they are extremely far away measured in thousand to million to billion of light year (fyi, 1 light year = 5.8 x 10^12 or about 6 trillion miles), so we're talking about astronomical number of measurement.

the Hubble constant varies also, meaning as the universe expanding, the Hubble constant is decreasing depending on observation.

but for now, the WMAP data provided picture of illuminating objects such as celestial objects near the center of galaxy, and gave us information about the color shifted, and we can then, used it to calculate the Hubble constant to be approximately 71 km/s/mpc.

this constant value is debatable but lets accept the data since there is no method to prove unless technology improve dramatically in the future.

now, the equation for the cosmological velocity of the expanding galaxy defined by the change in color shifted distance is:

v = c * ln(1+z)

where, c = speed of light, z = redshift.

now, to show that the speed of universal expansion is greater than light speed itself, we must showed that v (cosmological velocity) is greater than c (speed of light).

but to get v > c, we need the value of z (redshift) to be greater than 1.8 (z > 1.8 for v > c).

and the value of z (redshift can be calculated by Hubble's law:

z = (H*D)/c

with H = Hubble constant, D= distance of celestial object, c = speed of light.

i will not explain how we get z since we already know that for z > 1.8, the color of distant galaxy must be shifting toward red on the optical spectrum scale, because only redshift object can reach this value.

and surprisingly, the observable telescope data found most distant object with redshift is actually well over 1.8, even reaching over 5, like quasar emitting light about 5 billions year ago. that means distant galaxy with redshift with z greater than 1.8 is quite common.

and plug the value of z (either use z = 1.8 or 5) for the cosmological velocity equation:

v = c * ln(1+z)
v = 300,000 km/s * ln(1+1.8)
v = 308,886 km/s

or if z = 5 (like quasar moving away from each other), then v = 537,528 km/s.

which is higher than the speed of light c = 300,000 km/s. (ie, v > c).

so technically speaking, any distant galaxy with redshift greater than 1.8 is moving away from us faster than the light speed, and we have found that redshift objects in the universe.

that's why the expansion of space itself is accelerating faster than the speed ofl light by observing the light shift of celestial object in the universe.





are the "event-horizon" you mentioned is the blackhole's horizon right?

the initial thought of everyone, including Hawking himself and confused myself during a research study, predicted nothing escape the blackhole, but this is actually not true.

Hawking predicted that when mass/matter get absorbed by the black hole, it actually should evaporates out thermal or heat energy.

initially he was thought everything went into the singularity, nothing came out, and everything destroyed (which clearly violating conservation of mass/energy, 2nd law of thermodynamics).

however, his Hawking radiation theory, which he incorporated quantum mechanics and general of relativity, to save his theory.

in this theory, at the black hole's horizon, a set of two particles, one with positive mass and one with negative mass, appeared and annihilated each other out, forcing some radiation to escape in the process.

at quantum level, this process is called quantum fluctuation, where particles interact with virtual/opposite particles and destroyed each other, and it happened everywhere in space. this also implied nothing is actually empty at all because there is always ongoing activity of particle interaction.

anyway, back to the black hole's horizon, Hawking worked out the radiation equation which showed when stars' mass and matter get absorbed into the singularity of the black hole by its immense gravitational force, the negative/positive mass particles get sucked in, BUT some positive mass particles can escaped due to Heisenberg's uncertainty principle (ie, the unpredictability of the momentum and position of particles allowed this to happen), but it is still trapped inside the horizon.

that's how black hole radiates out heat trapping at its horizon.

though there is consequences for the black hole after absorbing negative charge particles. the black hole gets smaller and smaller to the point it can't held on and exploded, evaporating out "something" - Hawking claimed it's thermal radiation.

personally, i suspect it can be thermal radiation AND dark energy, which we still haven't discovered yet quite frankly.

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anyhow i can certainly be wrong since i'm still just at infancy stage of my astronomy study. lol

feel free to correct my mistake, i appreciate great discussion about nature.

lol, it is great possibility that there is nothing.

i used to think there nothing beyond that, but the thought of a finite universe is scary.

I don't want to think about it because it will just hurt my brain.

Again InitialDJay, your explainations are terrible ...
there is no doubt in your mind that you understand the theories
and that your explainations are adequate ...
unfortunately, they aren't ... lets not get into what is wrong ... there is just too much to go into

However, you do bring a situation with many possible imaginary scenarios.
Good for you. I do hope you find what you're looking for ...

I will not contribute to your quest for more answers ...
Cuz, I know that you do not believe me and
I'm afraid that you might steal my ideas for a book you may write in the future.
Good luck to you anyways.

^lol it's funny you criticize my explanation but never offer what's wrong in it, but instead keeping an ambiguous answer to yourself.. what a nice way to start a discussion, friend.

but you're right, i actually don't really trust what you said since you didn't demonstrate anything remotely intelligence.

however thank you for the straightforward reply.


though, one thing i LOVE is people to prove me wrong, so i can learn.

that's what i do when arguing with my classmates, even sometime the professor.

therefore anyone want to offer their scientific imagination over anything is greatly appreciated.

afterall, it is just an educated free-thinking topic.

Listen, it isn't what's scientific that is wrong but the way you try to explain it.

speed of light is constant in the same medium.
Light traveling in glass has a different speed/ slower.
Light traveling in air has speed which is close to a vacuum but is still ever so slightly slower.
I know this is picky but this is just one example
Therefore the speed of light is only constant in the same medium (vacuum).


Number one is the fundamental of matter ... that it can not travel faster than the speed of light.

It is not a fundamental condition of the nature of light's speed.
Time slowing down or stopping is a fundamental condition of light speed.

Do you see the difference?

See, I have no doubt that you believe you know and understand the theories
But, your explainations simply lack the ability to convey the ideas clearly.

Don't tell me that you want more ... I'm tired of trying to make sense of your posts.
Usually I go past your explainations and straight to the insulting part.

Okay, if you must ...


Fundamental conditions are the basics
But they don't work with the universal law of spacetime?
Really?????? Did you even try to make sense of that????


This sentence has one noun and a verb in the beginning and
then uses the object of the first part as a noun and then a second verb.
Meaning that this sentence doesn't make sense.
Read it again and try to make sense of what its saying.



This statement just came out of the blue with nothing to substantiate it.


Okay, that should be enough to let you know what I'm talking about.
It isn't empty criticism ... it isn't insults ... it is observation.
Are you happy now?
This is what you wanted from me ... to explain to you what you're doing wrong.
Hey, and that was from only one of your many posts

i already stated speed of light is constant in a vacuum in earlier post.

and for every physicists, when they refer to the constant speed of light, they assume it's in a vacuum, whether mentioned them or not.



we're talking about the fundamental condition of light speed, NOT time dilation of special relativity, which in fact doesn't violated when talking accelerating space too.

do you understand what i meant by the 1st condition? in a simpler sentence, it means anything with mass cannot be transmit or travel faster than light.





yes, read over or ask any astronomer or physicists.

the nature of space and nature of light are unrelated when you talking about comparable velocity.

this means space can be expanded faster than speed of light since space required no infinite energy because it is simply not energy substance.


it's my mistake that i write inappropriate sentence structure, but don't try to be semantic when you do it too sometime.

just a thought, i write as fast as my mind allows me at the time. consider my explanation like a draft paper, so to speak.

that's why i can clarify things afterward.. which is why we have a discussion forum to begin with.



absolutely you're right on that. i should've elaborate on that. but like i said, i wrote as fast as my mind was thinking.


wow for the first time, you're actually write something that i consider well-worth consideration.

your criticism is being accepted.



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anyway, if people think it's easy to explain a scientific concept, then feel free to demonstrate to me so i can learn and improve.

not that i need to, since most scientists are not good at writing and explaining too. it's the job of linguistic writer, editor, and teacher.

Not that You need to???
Really??? This has so much or your arrogance in this statement ...

It's the job of linguists, writers, editors and teachers???
Are you serious????
Who explains it to them so that everyone else can understand?
Teacher??? You want to put non-sense on paper and have a teacher grade it????

You may think you know your stuff ...
But your explainations lack clarity.

And, yes this is a forum for discussion ...
but if your presentation sucks then your argument can not hold up to scrutiny.

Think about it ....
If you find the answer to the equation of life's question
but you can't explain it so your contemporaries can understand it
it means you have accomplished nothing and will not be recognized.



Example of clarity in explaination:
Statement:
Traveling in space to get to the end of the universe, you will end up back where you started.

Explaination
It is like traveling on the oceans. You race for the horizon.
And in your travel, you will eventually end up back where you started.
This effect is due to your change of position or point of view.
The horizon that you knew of five minutes ago is not the same one you are viewing now.
And so, the horizon moves and you travel along the suface of this ocean which sits on a sphere.
Eventually you travel a cirlce and end up back where you started.
This is the analogy for traveling in space and racing for the horizon or edge of the universe.


Was that easy enough to understand?
Are your explainations any where near as clear???

Okay, never mind what I said ... go, you won this argument.
I forfeit ... you win

lol, o please tell me... you are not serious!! you don't get it do you?

why do you think the school hire science teacher? aren't their job is to explain while scientists' job is to research?

if textbook explanation is so clear, why do they need teachers?

also, here is a fact: people spend 25% organizing their research, 25% writing, 50% editing.

and when scientists publish a scientific explanation, they edit it majority of times and have their colleagues review their work before publishing.




i said it many times already... if you have question, you ask. in class, you have questions, raise your hand. doesn't your teacher taught you that in elementary school?

and i'm getting really irritate with you nitpicking every single details when my explanation was supposed to demonstrate a few contradicting points that guy made to my statement, so i immediately showed why space & light are unrelated and further proved it...

as for clarity, i can't read people mind.

also, it is much easier to explain something base on opinions than it is on facts.

same thing as, a persuasive paper is much harder to write than an informative paper.




i can't read people mind okay??

i can try, but no matter what.. if people don't say anything, i assume they "know" it already.




your analogy is unrelated to curvature of spacetime and very irrevalent.

furthermore, the lack of scientific fact or credibility in this statement makes it ambiguous.

first of all, you have to present how you know this? so people can be persuade by what you say is true. one way to do that, is cite a source OR theory or quote.

secondly, this explanation should be explain to a middle-school person.


anyway, whenever i present a discussion relating to science, it's usually you and me are discussing. aren't people not interesting in science or something?

i really don't know how advance is your scientific knowledge, but if you are, i would like to discuss a more advance subject if you're interest.

like the nature of gravity, since i'm still questioning this as a force...

Some battles are just not worth fighting <,< >,> lol

You will never understand because you simply don't want to ...
Your arrogance that you know much more than anyone else is beyond measure ...
Anyway, have fun playing with yourself, ...

for ONE, you are right, i am ARROGANT!






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does that look like a bird to you? lol