# Hotel Infinity paradox (your brain will hurt, promise)



## qubit (Dec 20, 2011)

> Imagine a hotel with an infinite number of rooms holding a limitless number of guests. What happens if an additional person arrives looking for a place to stay? Or if an infinite busload of people shows up?
> 
> In this animation produced by The Open University and narrated by actor David Mitchell, we follow a famous paradox proposed by mathematician David Hilbert that demonstrates the strange properties of infinity.
> 
> If you enjoyed this post, check out other episodes in our animated series such as how to comb a hairy ball or a video about machine intelligence.



Watch the video.

New Scientist


----------



## twilyth (Dec 20, 2011)

There are different flavors of infinity - countable and uncountable for example

http://www.sciencenews.org/view/generic/id/9269/title/Math_Trek__Small_Infinity,_Big_Infinity


----------



## trickson (Dec 20, 2011)

qubit said:


> Watch the video.
> 
> New Scientist



Dumb . Infinite is infinite . So no matter how you look at it every one will have a room . No matter how many show up ! Because you can not fill infinity up . It is the ultimate number !


----------



## pantherx12 (Dec 20, 2011)

trickson said:


> Dumb . Infinite is infinite . So no matter how you look at it every one will have a room . No matter how many show up !



+ one.

If an "infinite" hotel existed it would create new rooms as people turned up.

Or one room would exist how ever the key used would determine what point in time/space you ended up at.

Ultimately I think what is important here is that an infinite hotel would not exist. 


( I mean people moving rooms is no different to people who arrive going to those rooms that the people would of moved too.)


----------



## trickson (Dec 20, 2011)

pantherx12 said:


> + one.
> 
> If an "infinite" hotel existed it would create new rooms as people turned up.
> 
> ...



So no matter how many MORE people show up you would not need to have any one change rooms at all as there would still be more than enough room for them all . Man FUCK this ! My head hurts .


----------



## pantherx12 (Dec 20, 2011)

trickson said:


> So no matter how many MORE people show up you would not need to have any one change rooms at all as there would still be more than enough room for them all . Man FUCK this ! My head hurts .





Yup, if it were possible the "easiest" way to do this would be the key to one door that opened up to a different room way.

Multiple points in space time through the one door : ]

( When I say key, I mean some sort of key card as you could room 1 the code would be 1 and so on since counting is something that can go on infinitely this would work nicely)


----------



## theJesus (Dec 20, 2011)

trickson said:


> Dumb . Infinite is infinite . So no matter how you look at it every one will have a room . No matter how many show up ! Because you can not fill infinity up . It is the ultimate number !


I didn't watch the video, but that's exactly what comes to my mind as well.  Maybe I just have a very limited understanding of infinity.


----------



## Yukikaze (Dec 20, 2011)

trickson said:


> Dumb . Infinite is infinite . So no matter how you look at it every one will have a room . No matter how many show up ! Because you can not fill infinity up . It is the ultimate number !



To be nitpicky: Infinity is not a number.


----------



## Damn_Smooth (Dec 20, 2011)

theJesus said:


> I didn't watch the video, but that's exactly what comes to my mind as well.  Maybe I just have a very limited understanding of infinity.



To be fair, it's painfully obvious that the person you quoted and most others in this thread didn't watch the video either, because it has nothing to do with the hotel filling up.


----------



## pantherx12 (Dec 20, 2011)

Damn_Smooth said:


> To be fair, it's painfully obvious that the person you quoted and most others in this thread didn't watch the video either, because it has nothing to do with the hotel filling up.



I did watch the video, the very concept of the guys theoretical hotel is stupid.

It magically gets extra rooms when people move rooms, and yet people can't just walk in and head directly to those rooms.

You know maybe rather than making assumptions you should make a counter point to what people have already said, get a discussion going.


----------



## AphexDreamer (Dec 20, 2011)

What has been stated is obvious to me as well.

However... Unless they mean to say that each room is percicely filled up with 1 guest.

So a hotel with infinite rooms filled up with infinite people should have no room for a bus load of another infinite  load of people let alone 1 more person cause the otherwise infinite hotel has been filled with the infinite amount of people in it. 

I think I understand the paradox now. Never heard of it till now as well.


----------



## pantherx12 (Dec 20, 2011)

AphexDreamer said:


> What has been stated is obvious to me as well.
> 
> However... Unless they mean to say that each room is percicely filled up with 1 guest.
> 
> ...



It's not really a paradox though, it's just the basics of infinity.

I.E it's something with no limit.


Something that can never cease expanding is infinite.

Unless they are trying to highlight that the idea of infinity is a paradox it's self.

Then they are right 


There was dude who literally went insane from spending to much time thinking about infinity.

The same could happen to us if we're not careful


----------



## AphexDreamer (Dec 20, 2011)

pantherx12 said:


> It's not really a paradox though, it's just the basics of infinity.
> 
> I.E it's something with no limit.
> 
> ...



I think the paradox is how can you fill infinity when it is infinity? Which is what is happening in the paradox. 

I think that is what it is trying to accomplish?
They are trying to fill infinite rooms with infinite people so how can you add another infinite load of people let alone just one if they rooms are all already taken.


----------



## pantherx12 (Dec 20, 2011)

AphexDreamer said:


> I think the paradox is how can you fill infinity when it is infinity? Which is what is happening in the paradox.
> 
> I think that is what it is trying to accomplish?



But that isn't what it's saying though ( if it is that the video does not explain it very well at all)

It simply asks " what if an infinite amount of people turn up to an infinite hotel"

And simply you'll see a never ending ine of people going inside

Although as it's a hotel you would see a never ending line of people leaving the hotel as well.



Again it's not so much a paradox as simply what people understand to be infinity these days.


----------



## AphexDreamer (Dec 20, 2011)

pantherx12 said:


> But that isn't what it's saying though ( if it is that the video does not explain it very well at all)
> 
> It simply asks " what if an infinite amount of people turn up to an infinite hotel"
> 
> And simply you'll see people going inside for ever.



I swear I didn't cheat before! But I finally looked up the wiki version lol.


Consider a hypothetical hotel with countably infinitely many rooms, all of which are occupied – that is to say every room contains a guest. One might be tempted to think that the hotel would not be able to accommodate any newly arriving guests, as would be the case with a finite number of rooms.
http://en.wikipedia.org/wiki/Hilbert's_paradox_of_the_Grand_Hotel

The video was terrible at explaining it and I drew the same conclusions as everyone else till I thought about it a bit more. The wiki confirms my final way of thinking.


----------



## qubit (Dec 20, 2011)

I said your head will hurt people... lol  Infinity does that to you.

The more you think about infinity, the weirder it becomes and no-one on this planet understands it fully at its deepest level and likely never will.


----------



## AphexDreamer (Dec 20, 2011)

qubit said:


> I said your head will hurt people... lol  Infinity does that to you.
> 
> The more you think about infinity, the weirder it becomes and no-one on this planet understands it fully at its deepest level and likely never will.



Well the underlying problem here is people aren't even recognizing the paradox. I'm trying to shed some light on that first, then they can get lost in it.


----------



## pantherx12 (Dec 20, 2011)

qubit said:


> I said your head will hurt people... lol  Infinity does that to you.
> 
> The more you think about infinity, the weirder it becomes and no-one on this planet understands it fully at its deepest level and likely never will.



It shouldn't make peoples head hurt is the thing.


Something that doesn't have a limit is infinity.

It always baffled me how people over complicate it.

Infinite money = ceaseless amount.

Infinite universe = A universe that constantly expands.


----------



## pantherx12 (Dec 20, 2011)

AphexDreamer said:


> Well the underlying problem here is people aren't even recognizing the paradox. I'm trying to shed some light on that first, then they can get lost in it.



Because their is no paradox, infinity it's self is the only paradox.

Literally any reference to infinity is a reference to a paradox.


----------



## AphexDreamer (Dec 20, 2011)

pantherx12 said:


> It shouldn't make peoples head hurt is the thing.
> 
> 
> Something that doesn't have a limit is infinity.
> ...



I WON' STOP TILL YOU GET IT !!!

Yes that is all true, everyone who understands the paradox understands that. 

So now take a Hotel with infinite amount of rooms and now occupy every single one of those rooms with infinite amount of people.

Did you do that?

Now your hotel of infinite room has been filled to the brim (Complete booked, Totally Occupied) with an exact same amount of infinite people. 

Now can there possible be any more room to add any one else? Perhaps fit another bus full of infinite  people? 

Yes? No?


----------



## dorsetknob (Dec 20, 2011)

Theology predicts that there is one such place already and the management do not turn away anyone who arrives (with or without a reservation)


----------



## pantherx12 (Dec 20, 2011)

AphexDreamer said:


> I WON' STOP TILL YOU GET IT !!!
> 
> Yes that is all true, everyone who understands the paradox understands that.
> 
> ...



Yes and no.

Yes because there will always be more room as the infinite hotel would expand to meet demand.

No because people would always be entering the hotel because It's it's an infinite amount of people going in.


Again that is the very nature of infinity, infinity is ALWAYS a paradox.


----------



## AphexDreamer (Dec 20, 2011)

pantherx12 said:


> Yes and no.
> 
> Yes because there will always be more room as the infinite hotel would expand to meet demand.
> 
> ...



Right. And the wiki mentions this 

These cases demonstrate the 'paradox', by which we mean not that it is *contradictory*, but rather that a *counter-intuitive result is provably true*:


----------



## theJesus (Dec 20, 2011)

What I don't understand is the concept of adding an infinite amount of people to an already infinite amount of people.  It's like multiplying infinity by two, you get infinity regardless.


----------



## Damn_Smooth (Dec 20, 2011)

pantherx12 said:


> I did watch the video, the very concept of the guys theoretical hotel is stupid.
> 
> It magically gets extra rooms when people move rooms, and yet people can't just walk in and head directly to those rooms.
> 
> You know maybe rather than making assumptions you should make a counter point to what people have already said, get a discussion going.



Maybe before you go making assumptions you should read what I wrote. I said most, not all. Rooms take up space, I don't know how you think there can be an unoccupied room every time someone walks in. I don't know where you're getting this magically gets extra rooms from either, the rooms were already there.


----------



## pantherx12 (Dec 20, 2011)

AphexDreamer said:


> Right. And the wiki mentions this
> 
> These cases demonstrate the 'paradox', by which we mean not that it is *contradictory*, but rather that a *counter-intuitive result is provably true*:



The only head fucky thing about this hotel is that the person even thought about it in the first instance.


I thought it's common knowledge that infinity functions in this way, a demonstration like this is pointless.


Is this not the kind of thing people had discussions/arguments about as children when people used to say things like " I double dare you times infinite" and some other kid says " infinity + 1"




Damn_Smooth said:


> Maybe before you go making assumptions you should read what I wrote. I said most, not all. Rooms take up space, I don't know how you think there can be an unoccupied room every time someone walks in. I don't know where you're getting this magically gets extra rooms from either, the rooms were already there.



Your shitting me right?

By it's very definition a place with infinite amount of rooms would take up an infinite amount of space.

The only way to achieve that would be with a hotel that expanded as necessary, it doesn't even need to be magical the infinite amount of people could be building the hotel as more people come in.

If an infinite amount of rooms were already pre-existing then the place would have to be magical in order to exist, I.E not actually taking up any space at all.


----------



## Benetanegia (Dec 20, 2011)

Damn_Smooth said:


> I don't know how you think there can be an unoccupied room every time someone walks in. I don't know where you're getting this magically gets extra rooms from either, *the rooms were already there*.



Yes and no. That's the paradox of infinity itself.

Now regarding the OP:

The paradox of the hotel is silly. If there's any problem at all when the bus arrives, there's absolutely no way the infinite hotel would have been filled. So since the paradox establishes that the hotel is already filled with an infinte amount of people, we can safely assume that the infinte amount of people from the bus will get to their room *in the exact same way the other amount of infinte people did before.*

Of course another way to look at it is that the infinite hotel can never be full, because you can not fill infinite with any finite number, and that's what the paradox in the video is proposing.

This is where panther is 100% right.


----------



## Damn_Smooth (Dec 20, 2011)

pantherx12 said:


> The only head fucky thing about this hotel is that the person even thought about it in the first instance.
> 
> 
> I thought it's common knowledge that infinity functions in this way, a demonstration like this is pointless.
> ...



So you're actually treating this as if it existed? I thought it was rather self explanatory that it could never actually exist and that it was just something to think about.


----------



## pantherx12 (Dec 20, 2011)

Damn_Smooth said:


> So you're actually treating this as if it existed? I thought it was rather self explanatory that it could never actually exist and that it was just something to think about.



The Universe = The Hotel.

Infinite amount of space =/= Infinite amount of rooms


Hell even humans are technically infinite ( until we all die out anyway)

Our numbers are ever increasing without limit ( if we expand to areas outside of this planet)


It seems you've not thought about infinity all to much*, where as I've wasted many a sleepless night already ha ha

Like I said, I spent my childhood going through this sort of thing : ]


* This is not designed to be an insult in anyway, infinity is a pretty pointless albeit very interesting subject.

People not wasting their time on it is probably a good thing.


----------



## Damn_Smooth (Dec 20, 2011)

pantherx12 said:


> The Universe = The Hotel.
> 
> Infinite amount of space =/= Infinite amount of rooms
> 
> ...



I would die before I walked to the other end of the universe. I'm not even sure if a human could walk around the earth in a lifetime. Assuming that there was no water in the way.

Yes, you could spend forever thinking about infinity.


----------



## Benetanegia (Dec 20, 2011)

Damn_Smooth said:


> I would die before I walked to the other end of the universe.



Unless you were travelling as close as posible to the speed of light. To be precise at v = c - 1/infinity.


----------



## Damn_Smooth (Dec 20, 2011)

Benetanegia said:


> Unless you were travelling as close as posible to the speed of light. To be precise at v = c - 1/infinity.



Even at light speed. I have about 50-60 years left if I'm lucky. I wouldn't make it across the universe in that short of time.


----------



## qubit (Dec 20, 2011)

theJesus said:


> What I don't understand is the concept of adding an infinite amount of people to an already infinite amount of people.  It's like multiplying infinity by two, you get infinity regardless.



Yes you do, that's why it's weird. I've a slight headache...


----------



## Drone (Dec 20, 2011)

Yukikaze said:


> To be nitpicky: Infinity is not a number.



Yes in maths infinity is a set. And one set can be wider than other. Actually maths doesn't have a single conception for infinity.


----------



## pantherx12 (Dec 20, 2011)

Benetanegia said:


> Unless you were travelling as close as posible to the speed of light. To be precise at v = c - 1/infinity.



He still wouldn't even get close though XD

From here the end of the observable universe is about 45 billion light-years away or something crazy.


And there's still more beyond that !


----------



## Benetanegia (Dec 20, 2011)

Damn_Smooth said:


> Even at light speed. I have about 50-60 years left if I'm lucky. I wouldn't make it across the universe in that short of time.



Time dilation. Yes universe is (almost) infinite, so even at speed of light it would take you an (almost) infinite amount of time, based on any frame of reference other than yourself. For you it would only be 50 years, or only 1, who knows, depends on how close to c you could travel and how much your time was dilated.


----------



## Damn_Smooth (Dec 20, 2011)

Benetanegia said:


> Time dilation. Yes universe is (almost) infinite, so even at speed of light it would take you an (almost) infinite amount of time, based on any frame of reference other than yourself. For you it would only be 50 years, or only 1, who knows, depends on how close to c you could travel and how much your time was dilated.



I'll let you know when I get there.


----------



## Fourstaff (Dec 20, 2011)

Read up on Cantor's work on cardinal numbers.


----------



## Drone (Dec 20, 2011)

pantherx12 said:


> From here the end of the observable universe is about 45 billion light-years away or something crazy.



It's 13.7 billion ly


----------



## dorsetknob (Dec 20, 2011)

here is another headfu*K for ya

whats the square root of infinity


----------



## pantherx12 (Dec 20, 2011)

Benetanegia said:


> Time dilation. Yes universe is (almost) infinite, so even at speed of light it would take you an (almost) infinite amount of time, based on any frame of reference other than yourself. For you it would only be 50 years, or only 1, who knows, depends on how close to c you could travel and how much your time was dilated.



Isn't the general consensus that if a person were to travel at light speed their time would be experienced as per normal how ever an observer not travelling at light speed would be experiencing time 7* times faster than the person at light speed?


* May of got number wrong 

I tell you what I really wish I didn't have difficulties with words, I'm not sure if what I wrote just then will make any sense to anyone else lol.

So to put it simply.

If I travelled at light speed for one year I'd of aged 1 year but all my friends back on earth would of aged 7 years.


----------



## theJesus (Dec 20, 2011)

Everybody, all your answers are right here, in this guy's head:


----------



## pantherx12 (Dec 20, 2011)

Drone said:


> It's 13.7 billion ly



Only because the light we get is ancient so it would seem closer where as it is actually around 45 billion light years away : ]

( since the universe is expanding)

http://www.astro.ucla.edu/~wright/cosmology_faq.html#DN


----------



## Benetanegia (Dec 20, 2011)

pantherx12 said:


> Isn't the general consensus that if a person were to travel at light speed their time would be experienced as per normal how ever an observer not travelling at light speed would be experiencing time 7* times faster than the person at light speed?
> 
> 
> * May of got number wrong
> ...



No, time dilation approaches infinity as v gets close to c.

Where did you hear that anyway?


----------



## W1zzard (Dec 20, 2011)

infinity is an abstract concept and does not exist in the physical universe, so linking infinity and physical things leads to paradoxes because the underlying assumption is wrong (that something physical an be infinite)

it doesn't stop you from doing math with it of course


----------



## pantherx12 (Dec 20, 2011)

Benetanegia said:


> No, time dilation approaches infinity as v gets close to c.
> 
> Where did you hear that anyway?



TBH man I'm not entirely certain, it was quite some time ago when I was still at school and expecting to get a career in the field of science.

Then I got kicked out of school 


Since then a lot of stuff has kind of dissolved away in my mind, it's not that I'm no longer interested it's just a whole lot easier to study when amongst peers, and all to easy to procrastinate when your by yourself.


Sorry for off topic post  But I felt a simple " I don't know" didn't really suffice because I thought I knew.


I think being up for 24 hours isn't helping me remember though so I'll sleep on it, perhaps ask my dad if he has ever heard of the same figures he might be able to point me in the right direction or tell me I'm thinking of something entirely different


----------



## Drone (Dec 20, 2011)

pantherx12 said:


> Only because the light we get is ancient so it would seem closer where as it is actually around 45 billion light years away : ]
> 
> ( since the universe is expanding)
> 
> http://www.astro.ucla.edu/~wright/cosmology_faq.html#DN



Yes right. The 13.7 b ly is a _static_ radius, beyond that it can get up to 47 billion light years and more. Due to accelerated expansion of space-time and the finiteness of speed of light what we see isn't actually the present events. That's why there are terms _comoving_ distance and _proper_ distance.

http://universe-review.ca/F02-cosmicbg.htm

In that article they say that radius of the universe is 10^28 cm, and that universe has 10^11 galaxies, 10^21 stars, 10^78 atoms, 10^88 photons.


p.s. Many scientists wonder why speed of light is 3e8 m/s and not infinity. If particle can have zero mass why it can't have infinite velocity. Or 3e8 is some kind of "infinity" for speed.


----------



## Benetanegia (Dec 20, 2011)

Drone said:


> p.s. Many scientists wonder why speed of light is 3e8 km/s and not infinity. If particle can have zero mass why it can't have infinite velocity. Or 3e8 is some kind of "infinity" for speed.



That's true for every universal constant I think.

Personally I've always considered that our universe is "moving" or "falling" along 1 or various temporal dimensions. Something like a 2 dimension plane falling flat in the 3rd dimension if you get what I mean.

So since "time" is accelerating at a very fast rate, nothing can reach infinite speed and instead can only travel at a set speed. Mathematically it's like an infinity minus infinity, or infinity divided by infinity situation.

EDIT: Another explanation. Our universe (the one that is apparent to us) is the n-th dimensional equivalent of an "sphere". Just like gravity is (almost) constant throughout the surface of Earth, speed of light is constant within the surface of our "spherical" universe. 

What I mean when I say spherical universe is not literally a sphere, but that such as a sphere in a 3d cartesian coordinate system is defined as:

x^2+y^2+z^2= r^2, where r is the radius

for our universe it would be:

x1^2+x2^2+...+xn^2 = r^2, where n is the number of dimensions that the universe really has and r is a constant yet to be discovered.

Now to complicate things even more, I don't think the universe would be an sphere (remember what I really mean by sphere), but some kind of elipsoid. Same concept, various constants.


----------



## Damn_Smooth (Dec 20, 2011)

pantherx12 said:


> TBH man I'm not entirely certain, it was quite some time ago when I was still at school and expecting to get a career in the field of science.
> 
> Then I got kicked out of school
> 
> ...



I think that you are talking about gravity's effect on time where people on earth age faster than people in space. I have heard that, but I am far from an expert on this shit.


----------



## Drone (Dec 20, 2011)

Benetanegia said:


> So since "time" is accelerating at a very fast rate, nothing can reach infinite speed and instead can only travel at a set speed. Mathematically it's like an infinity minus infinity, or infinity divided by infinity situation.



Yes and it's strange because all we see isn't just changing in time but also in space. Like Sagan said if we had a magic camera that could take "immediate" shots (with infinite velocity) then we could see the *real* events (ears on photo would appear later than nose).

Even tho the "*speed of gravity*" seems to be *infinite*/immediate otherwise if gravity propogated with slower speed every galaxy would fall part.

http://metaresearch.org/cosmology/speed_of_gravity.asp

But some say it's just too fast (maybe x10^10 or more faster than speed of light) but finite. Go figure ...


----------



## bostonbuddy (Dec 20, 2011)

x/0


----------



## qubit (Dec 20, 2011)

Drone said:


> Even tho the "speed of gravity" seems to be infinite/immediate otherwise if gravity propogated with slower speed every galaxy would fall part.



Gravity propagates at the speed of light.


----------



## entropy13 (Dec 20, 2011)

lol at the posts about infinity


----------



## Drone (Dec 20, 2011)

qubit said:


> Gravity propagates at the speed of light.



Yes general relativity says so. But it's confusing just like a spooky action at a distance.



> In Einstein's theory of general relativity gravitational interaction is mediated by deformation of space-time geometry. Matter warps the geometry of space-time and these effects are, as with electric and magnetic fields, propagated at the speed of light. In Einstein's theory of motion, matter acts upon space-time geometry, deforming it, and space-time geometry acts upon matter.



Actually gravity _cheats_. It acts immediately because of the curvature of space-time. And even tho its speed is finite (c) it acts _faster_ than light. In quantum mechanics word "faster" means using a shorter route, not having a faster velocity. Cosmic laziness, Geodesic Lines, Non-Euclidean Geometry and all that jazz .... you know. 



> The speed of gravitational waves in the general theory of relativity is equal to the speed of light in vacuum, c. Within the theory of special relativity, *the constant c is not exclusively about light*; instead it is the highest possible speed for any physical interaction in nature. Formally, *c is a conversion factor for changing the unit of time to the unit of space*. This makes it the only speed which does not depend either on the motion of an observer or a source of light and/or gravity. Thus, the speed of "light" is also the speed of gravitational waves and any massless particle. Such particles include the gluon (carrier of the strong force), the photons that light waves consist of, and the theoretical gravitons which make up the associated field particles of gravity (a theory of the graviton requires a theory of quantum gravity, however).



To get the answer we need to know all the theories: General Relativity, Special Relativity, Quantum Mechanics, Quantum Gravity Theory, Theory of Everything, M-Theory, Expanding Space-Time Theory, Supersymmetry, String theory (D-Branes), Unified field theory. Unfortunately the current status of all these theories is incomplete.



Benetanegia said:


> for our universe it would be:
> 
> x1^2+x2^2+...+xn^2 = r^2, where n is the number of dimensions that the universe really has and r is a constant yet to be discovered.
> 
> Now to complicate things even more, I don't think the universe would be an sphere (remember what I really mean by sphere), but some kind of elipsoid. Same concept, various constants.



Ellipsoid has _different_ r along each axis (for 3D it's a, b, c when a=b=c it's sphere), in that case for every dimension there has to be a separate r.

String theory and supersymmetry theory say that our universe is 10D. After the Big Bang 3 dimensions grew bigger but other extra 7 dimensions remained tiny, hence undetectable.

I digress but here's an interesting snip:



> Gravity can be properly localized to a sub-spacetime. Gravity acting in the hidden dimensions affects other non-gravitational forces such as electromagnetism. In fact, Kaluza's early work demonstrated that general relativity in five dimensions actually predicts the existence of electromagnetism. However, because of the nature of Calabi–Yau manifolds, no new forces appear from the small dimensions, but their shape has a profound effect on how the forces between the strings appear in our four-dimensional universe. In principle, therefore, it is possible to deduce the nature of those extra dimensions by requiring consistency with the standard model, but this is not yet a practical possibility. It is also possible to extract information regarding the hidden dimensions by precision tests of gravity, but so far these have only put upper limitations on the size of such hidden dimensions.



In a nutshell: we are stuck in 3D space (there are other dimensions tho), but gravity can "leak" into other dimensions, and even from there it can affect our world. And our world with all its interactions also depends on the shape of those tiny dimensions. Some scientists think that extra dimensions got something to do with dark matter and energy. And maybe it's  even possible to create a "shortcut" (wormholes) through the extra dimensions to our world, in that case we could travel with infinite speed and immediatley appear in any desirable spatial and maybe even time destination.





Wow my post is huge


----------



## AlienIsGOD (Dec 20, 2011)

Damn_Smooth said:


> I'm not even sure if a human could walk around the earth in a lifetime.



It is very possible.  Google can be your friend


----------



## horik (Dec 20, 2011)

I think infinity is impossible so getting a right answer about question related with it is impossible.The question is stupid,if you try to answer you are accepting that there can be more infinities in the space of 1. This is like asking:if a ship flies at an infinite speed,another ship flying at double that speed would be faster?I go to sleep e_e


----------



## Benetanegia (Dec 20, 2011)

Drone said:


> Ellipsoid has _different_ r along each axis (for 3D it's a, b, c when a=b=c it's sphere), in that case for every dimension there has to be a separate r.



Yeah I know that. As I said, same concept but different constants. I went with an sphere to make explaining the concept easier and I guess I didn't explain myself properly anyway. Well, mentioning the sphere, I was just trying to explain the concept of "living in a surface", you know, to draw a parallelism between g (on Earth's surface) and c on our apparent universe. Speed of light could be any value, even infinite in the broader universe, and our apparent universe might just be that one (subset) in which c=300000 km/s.



> String theory and supersymmetry theory say that our universe is 10D. After the Big Bang 3 dimensions grew bigger but other extra 7 dimensions remained tiny, hence undetectable.



Yeah, and isn't there one that says there's 23? What I think is that we don't really know how many dimensions are there in the universe. And whenever we find out exactly how many are there in "our universe", if we happen to live in a "subset" of a broader universe we might never find out how many are there on top of the ones that define our universe.

For example a living being that belongs to a universe with only 2 spatial dimensions would be able to sense or explain a 3rd dimension? Since his universe is just as "defined" by the lack of a 3rd dimension as he is, would he even theoritize about it's existence?


----------



## trickson (Dec 20, 2011)

W1zzard said:


> infinity is an abstract concept and does not exist in the physical universe, so linking infinity and physical things leads to paradoxes because the underlying assumption is wrong (that something physical an be infinite)
> 
> it doesn't stop you from doing math with it of course



I disagree , There are an infinite number of assholes on this planet .


----------



## Yukikaze (Dec 20, 2011)

trickson said:


> I disagree , There are an infinite number of assholes on this planet .



That number is actually easily bounded, thus not infinite


----------



## trickson (Dec 20, 2011)

yukikaze said:


> that number is actually easily bounded, thus not infinite :d



 LOL that is funny .


----------



## Drone (Dec 20, 2011)

Benetanegia said:


> Yeah, and isn't there one that says there's 23? What I think is that we don't really know how many dimensions are there in the universe. And whenever we find out exactly how many are there in "our universe", if we happen to live in a "subset" of a broader universe we might never find out how many are there on top of the ones that define our universe.



26 to be exact but that's for bosonic string. And only 10 for the superstring (particles + interactions, aka our regular universe which modelled as vibrations of tiny supersymmetric strings).



> For example a living being that belongs to a universe with only 2 spatial dimensions would be able to sense or explain a 3rd dimension? Since his universe is just as "defined" by the lack of a 3rd dimension as he is, would he even theoritize about it's existence?



Theorizing is always possible because knowledge science intuition and imagination ain't limited. Let's take simplex. 4D simplex is a pentachoron. Even it's hard to imagine but it can easily be formulated through the geometry. Well mathematically everything is always easier than visually.


----------



## Benetanegia (Dec 20, 2011)

Drone said:


> Theorizing is always possible because knowledge science intuition and imagination ain't limited. Let's take simplex. 4D simplex is a pentachoron. Even it's hard to imagine but it can easily be formulated through the geometry. Well mathematically everything is always easier than visually.



Ok yes, it could be theorized to an extent, but it wouldn't form part of science, even if someone could come up with something crazy, because it wouldn't be able to be proven or falsified. That's what I meant. For example, if "speed of light" (in the broad sense, the maximum speed that a non massive particle can achieve) is actually a dimension, or something affected by one dimension, and that just happens to be constant through our universe (maybe because that's in fact the trait that sets appart our universe from others). How could we prove it? c would still be constant in our universe, and if we have no means to "trascend" our universe I don't see how could we theorize something like that. If only c is affected by that dimension (or is the dimension itself) and it's constant for us, that's the end of it.


----------



## Drone (Dec 20, 2011)

Benetanegia said:


> Ok yes, it could be theorized to an extent, but it wouldn't form part of science, even if someone could come up with something crazy, because it wouldn't be able to be proven or falsified. That's what I meant.



That's why scientists work on Grand Unified Theory. We can't even explain mass, we can't explain gravity. We can't find Higgs or graviton. We can't say will proton decay or not. Many things ain't proven it doesn't mean we have to chuck Standard Model or relativity. It all can be explained sooner or later. For that they just need to work in different directions such as supersymmetry, quantum mechanics, string theory and so on. And finally find something general which could be integrated into TOE (theory of everything). Extra dimensions, dark matter and dark energy shouldn't scare us off.


----------



## AphexDreamer (Dec 20, 2011)

Drone said:


> That's why scientists work on Grand Unified Theory. We can't even explain mass, we can't explain gravity. We can't find Higgs or graviton. We can't say will proton decay or not. Many things ain't proven it doesn't mean we have to chuck Standard Model or relativity. It all can be explained sooner or later. For that they just need to work in different directions such as supersymmetry, quantum mechanics, string theory and so on. And finally find something general which could be integrated into TOE (theory of everything). Extra dimensions, dark matter and dark energy shouldn't scare us off.



Btw we've just recently found evidence for the Higgs Boson

http://www.dailymail.co.uk/sciencet...on-First-hard-evidence-God-particle-CERN.html


----------



## NinkobEi (Dec 20, 2011)

inifnity / 0 = mind blown


----------



## MilkyWay (Dec 20, 2011)

Infinity goes on for ever so you can never fill up infinity. If new guests arrive then they would all have to move up rooms and those rooms would be filled up in an endless cycle because you could never fill them up. All those rooms all instantly exist at the same time.

At the same time every infinite room is already taken up so there can be no more room, which is why its a paradox.


----------



## qubit (Dec 20, 2011)

I see that people's brains are hurting nicely here. Don't worry my friends, the finest minds in science couldn't fully get it either and more than one went nuts trying...

Now, just try getting your heads around infinitesimals: teeny tiny non-zero values infinitely close to zero that you can never measure...


----------



## AphexDreamer (Dec 20, 2011)

Or trying warping your head around the fact that there is no such thing as the present, only the immediate past and imminent future.
http://en.wikipedia.org/wiki/Present

Although I must point out early the grammatical meaning of the word does exist.


----------



## Drone (Dec 20, 2011)

AphexDreamer said:


> Or trying warping your head around the fact that there is no such thing as the present, only the immediate past and imminent future.



Yes because space-time is descrete (Planck time 10^-44 s and Planck length 10^-35 m as building blocks). Quantum mechanics might suggest that space-time is a quantum and not continuum thing. We know that space-time can be affected by gravity so maybe space-time is made of quantums and has a mass.


----------



## pantherx12 (Dec 20, 2011)

AphexDreamer said:


> Btw we've just recently found evidence for the Higgs Boson
> 
> http://www.dailymail.co.uk/sciencet...on-First-hard-evidence-God-particle-CERN.html



Any other sources for that news?

Basically anything in the daily mail should be disregarded until proven otherwise


----------



## qubit (Dec 20, 2011)

Hey, trust a thread about infinity to go on and on.

Think about it.


----------



## Yukikaze (Dec 20, 2011)

pantherx12 said:


> Any other sources for that news?
> 
> Basically anything in the daily mail should be disregarded until proven otherwise



http://press.web.cern.ch/press/PressReleases/Releases2011/PR25.11E.html

Not quite confirmed yet.


----------



## Damn_Smooth (Dec 20, 2011)

AlienIsGOD said:


> It is very possible.  Google can be your friend



Google can be everyone's friend if they care enough to use it.


----------

