Internet & Space

Is the Internet like Space? Like it will keep expanding and will never end?

What do you mean by exapnd?

It is a fact that the Universe is expanding (getting bigger). New Galaxy's are forming and Space is unlimited. Is space on the internet unlimited?

[Sam Finch]

not really, the internet is a load of 1s and 0s, space is different.

there's no limit as such to the internet, it expands as more information goes on it and more computers are attatced to web servers. but is isn't space, it's information, the 2 things are too different to compare.

I think the internet is quite like space.
when you are in space, and you are not on a planet(website) where are you, just floating, doing nothing.
then your air supply runs out(inactivity) then you die(get booted off)


;)

and it does seem like the internet goes on forever.
there are litarlly millions of webpages out there....

oh, since where kind of talking about space...
how does the universe go on forever?
I mean what contains the universe?
is there anything that can contain the universe?
and the #1 question I want answered is.... <drum roll, brbrbrbrbbr>

how do we know so much stuff about space, like how do we know about black holes, how do we know that stars are made of plasma?
how do we know about phantom matter??

[RealisticGraphics]

The universe is a borderless sphere that is wrapped around the outside of another sphere. Which means it is never ending. You can never visualize what the universe actually looks like because humans are incapable in thinking in 4 dimensions, we are limited to 3. To put it in programming terms:

Do
sphere1.width = infinite
sphere2.width = sphere1.width * infinite
sphere3.width = sphere2.width * infinite
'Do this for an infinite number of spheres.
loop

For more information please see "Hyperspace" by Michio Kaku or "A Brief History of Time" by Stephen Hawking (pronounced Stefen).

[Sam Finch]

Do
sphere1.width = infinite
sphere2.width = sphere1.width * infinite
sphere3.width = sphere2.width * infinite
'Do this for an infinite number of spheres.
loop


what do you mean by this, there are loads of different types of infinities, if you start with the only type of infinity that makes sense for a width then you get the same type of infinity at the end.

[RealisticGraphics]

It simply means that there is no end to the universe. It simply goes on forever into infinity. The universe is a three-dimensional sphere which is wrapped around the outside of a four-dimesional sphere and so on.

[Sam Finch]

hmm, doesn't make too much sense.

[RealisticGraphics]

It's all very complicated, and impossible to even visualize. The human mind is not powerful enough to think in the way needed to visualize what it actually looks like. The books I named before can explain in more detail.

Do
sphere1.width = infinite
sphere2.width = sphere1.width * infinite
sphere3.width = sphere2.width * infinite
'Do this for an infinite number of spheres.
loop


You cannot have this because infinity is infinity. There is no such thing as 2(infinity). or infinity / 2.

Refer to the topic Infinitly Interesting for a debate about it.

They know a lot about Space because...Voyager I, which was set off course after Saturn went into the "outer space" and Voyager II which past Pluto in 1999 will explore the space far beyond.
I've heard that Voyager II has discovered two new planets that look like Saturn (http://www.discovery.com).
Both Voyager take pictures all over.
They do not come back exact pictures.
They come back in binary form (1010100101).
And the way they can tell how the Universe is expanding is through radio waves.
A short radio wave would look like this "M".
But when they hold their equipment up to space, it looks like "/\/\/". Spread out more.
And it keeps getting further and further apart.
We have yet to explore :). It is so big, alien life must exist. We cannot be the only ones in a never ending universe.
The Milky Way Galaxy, for example is huge.
It is a spiral galaxy. We are located on an end.
It consists of billions, maybe even trillions of stars and there is even beyond that..more galaxys.
Galaxys that are forming new areas.
And new galaxys being created. And what you may have heard, a black hole, if you go through it, you don't end up anywhere. It is so dense, the pressure will crush you.
Go here, you will see how much you weigh on other planets, our sun, a nebula (new galaxy formation), a white dwarf (after a Super Giant star explodes): http://www.exploratorium.edu/ronh/weight/

Black hole is not on there, but it is probably as dense as a Neutron Star.

Space/Astonomy is my favorite subject :).

I am sooo intelegant I am able to think in 4d :D
see, I am so intelegant that I can think in 4d, but all that thinking made me forgor how to spell intelegant.. :D

any one care to take an educated guess on what your IQ would have to be to think in 4d?
what 1k, 2k, 3k?
or maybe 174?
I hope its 174 :D

In the 1st, 2nd, and 3rd dimensions, we have up and down, left and right, and three-dimensional. What is the 4th dimension?

[Penar]

Originally posted by Matthew Gates
Is the Internet like Space? Like it will keep expanding and will never end?

As long as we don't ran out of Ip's...

[Gen-X]

RG

You forgot one thing to mention on space.

Your "wrapped around a sphere" is trying to describe time/space bending so much it folds in on itself until it looks like a sphere in all 3 dimensions simultaneously.

That doesn't mean its "infinate". It means if you travel in the same direction you would eventually end up at the point you started from.

Imagine walking on the earth. Walking can be considered 2D because we can only go left/right and forward/backward. If we picked a direction and travelled we would eventually return to the point we started. The world is therefor described in 3D.

This would be the same of the universal model based on the bending of time and space however our "walking" is now in any of the 3 directions but we would still end up at our starting point but the "sphere" is now in 4D not 3.

Matthew

No the Internet is NOTHING like space.

Space continues to expand without any need nor requirement to communicate with the parts it is expanding away from.

The Internet on the other hand much ALWAYS remain connected with (although through intermediate points) every other point on that network.

Thus the difference is seen in the fact that the longer the distance the slower the connection on the internet meaning the "biggest" the internet can be is directly dependant on how fast we can transmit information between computers.

Don't forget... although we may "transmit" at the speed of light via electricity or optic fibre, the fact it is carried in a medium other than vaccum means it is degredated and requires boosting via "repeaters". We also must store not only the information in webpages but each computer connected to the internet needs to either HAVE or HAVE ACCESS TO a DSN (Domain Name Server). If we increase the number of sites out there by a factor of 100 it means we need 100 times the storage space in order to keep track of the different IP addresses (or ways of getting to computers that have them).

So there are limits :)

This would be the same of the universal model based on the bending of time and space however our "walking" is now
in any of the 3 directions but we would still end up at our starting point but the "sphere" is now in 4D not 3.

Space does not bend as a sphere. If it is infinit, than it cannot have a definet shape.

[Gen-X]

Megatron

You really don't understand gravity and Einstein do you :(

Let me give you a picture in 3D.


Gravity
Ball-->* |
--------\ /-------- |
Hole--> \_/ V


Imagine someone "rolling" a ball along the ground and that ball reaches a hole. The ball will "fall" into the hole because gravity is pushing down on it. Now if this hole is on the surface of the world at one end, a hole on the other end is going to do exactly the same thing...

"Gravity causes ALL things to FALL towards the centre"

Now what actually causes gravity to happen is "MASS". The MASS of the earth is what gives us 9.8 m/s2 or what we consider gravity. You know that it acts in ALL directions regardless of where I stand on the earth.

What Einstein theorized and what others have deduced is that gravity is a "hole in 3 dimensions". Imagine the flat ground in the above example being the fabric of space. A body of mass causes this fabric to BUCKLE, just like placing a large bowling ball on the ground would cause a dent. But it isn't flat... the BUCKLE is in ALL 3 dimensions at once.

So its like imagining a hole that no matter WHERE you look at it you always see the hole and you ALWAYS fall towards it

THIS is how time/space is "bent"... Of course you don't SEE the bending because it bends the light (photons) that hits your eyeballs, so everything looks straight.

Trust me Megatron... that IS the way it works.

[noone]

I belive we already have run out of IP addresses or we will run out soon. MAC addresses will probably run out soon too. IP address are 32 bit so we can have 2 ^ 32 different IP addresses. I know that sounds like a lot but their are a lot of addresses being used and a lot wasted. Cisco has devoloped IP Version 6 I belive to be used on Internet 2. OF course that will be propietry to Cisco. Arent you all glad you have Cisco shares???

9.8 m/s2

Is this the rate at which gravity falls?

[SteveCRM]

My class just went to the museum of natural history in New York City. They have the most powerful space simulating projector in the world. They said the universe is made up of 5 parts, well from our perspective, starting at earth...

1. Earth
2. The Solar System
3. Milkey Way Galaxy
4. Virgo Supercluster
5. Observable Universe

The observable universe is the whole universe viewed from far away, (it looks like a cloud almost) Is this very acurate?

As for the museum, I really recommend seeing that planetarium! It appears 3D, and boy! That was amazing, really made me feel really little. And I thought the CN Tower in Toronto was big!

Yes, i saw that 5 part universe on TV before. the show was about evolution of the Universe.

Here's something interesting. Picture the Sun as a dot with a diameter of 0.1mm. Now using that scale, the estimated size of the universe is the distance from Montreal to Winnipeg!!

[SteveCRM]

Wow, that just made me feel really insignificant

Yes, it's a lot when you think about it. It boggles the mind to think in such vast measures.

They say 1000 Earth's can fit inside Jupiter. And I believe about 10 Jupiter's can fit inside the sun. The sun is huge. But our sun is only at it's mid-ages. If you compare it to a supergiant..now that's huge!

Did you all know, when you look up into the sky, your actually looking into the past. Stars could be billions of years old. Light travels at 300 000 KM/S. The time light travels in one year is 9.6 trillion km. It takes years for light to reach Earth. Our sun's light takes 8 minutes to reach Earth, so when we look up at our sun, its 8 minutes into the past we are looking at. Only if we could travel in space using light speed. But, this technology won't be around for this human generation. :(

Hopefully, we'll get to do something in space our life time. I'm sure you've all dreamed of going into space..even if it meant for a short time, just to see how it is. I know I want too. Floating, not weighing anything, that'd be cool :). Unless you become an astronaut. I think I'm going to either be a programmer or an astronomer. But let's not get into my life.

[SteveCRM]

Looking into the past, it is an odd concept to grasp. But it is really interresting. My friends think Im nuts because I can stare at the stars or go a computer for hours.

[Gen-X]

Megatron

9.8 m/s^2 is the acceleration of gravity for EARTH only. Each body of mass has its own rate of gravity which is based on the actual MASS of the object.

All

Talking of looking into the passed... hasn't anyone ever wondered why if the universe is infinate (or even if it is finite but connected) that we don't see a WHITE sky filled with the light from every sun rather than a BLACK sky with a few stars?

The answer is simple. Photons

While they say 100 billion billion photons strike the surface of a pinhead in a single second on a sunny day... the whole reason we don't see a white sky is because at extremely large distances the photons from particular suns are going either side of us.

I will have to increase the scale in order to make it understandable but picture this :

Imagine 2 photons coming off the surface of the sun. They are going at 0.01 degrees difference between each other. This means that if you were only 500 m away from the sun BOTH photons would strike your eye allowing you to "see" it. Now imagine you are 5,000,000km away, possibly only ONE photon would strike your eye because the second one which is SLIGHTLY off from the first hits your cheek.

Now expand that again so that you are 5,000,000 light years away. BOTH photons miss you now because one went to one side of the earth and the other to the OTHER side of the earth. Effectively no matter WHERE we are we will never see the light from that star because at extreme distances the photons never reach us.

Take this a step further... and it brings an AMAZING feature.

Sailors navigate by the stars, they have "maps" which show what the skies look like and determine where they are in relation to those (ie some constellations can only be seen from the southern hemisphere and others from the northern)

But if we were in another Galaxy... lets say Proxima Centauri our closest neighbour, there could be photons which MISSED the Milky way that STRIKE Proxima and vice versa... This would mean that there would NOT be a common set of stars from both the Milky Way and Proxima... they would possibly be very different as a result of this effect.

So navigating through space by patterns in the stars wouldn't really be possible in distances between different galaxies.

In my science book, it says that in our solar system, the sun contains 99% matter and the other 1% is just everything around it that's contained in the solar system.

And in order to travel far distances in space, we cannot do that now because there simply isn't enough gas. Therefore, humans have to learn to capture and use fusion from the sun. With fusion, you could travel at light speeds. They are using energy from the sun...steam and certain other things. :)

But, referring back to the first paragraph, that's a lot of matter for one object! :p

[Gen-X]

In my science book, it says that in our solar system, the sun contains 99% matter and the other 1% is just everything around it that's contained in the solar system.


The gravity of the sun is a few order of magnitudes greater than that of Earth. This means it can "squash" matter into very small spaces, hence it contains 99% of our solar systems total number of particles.

But think about a black hole.. it contains the equivalent of --4-- of our Suns in a space no larget than a cubic centimetre. The Gravity is So high that even light cannot escape.


And in order to travel far distances in space, we cannot do that now because there simply isn't enough gas. Therefore, humans have to learn to capture and use fusion from the sun. With fusion, you could travel at light speeds.


I don't think so. Even if we harness fusion there is always the problem of being able to contain the reaction. You are after all causing 2 particles to "FUSE" into a single particle. The amount of pressure and temperature required to do that is so high that you need some serious science to stop the WALLS of what you are fusing inside from doing the same thing...

The higher the MASS of an object the more energy required to make it go faster (ie You can push your car but you cannot PUSH a truck). Something that had a fusion reactor inside it would probably weigh several thousand tonnes... to get that amount of MASS moving would be more than the amount of energy inside the fusion reactor in the first place


They are using energy from the sun...steam and certain other things.


*sigh* I think its about time we stopped using the BRUTE FORCE approach. You only succeed when you find ways "around" the problem... not the problem itself.


But, referring back to the first paragraph, that's a lot of matter for one object!


Enough to hold 9 planets and 20+ moons... and yet the Milky Way Galaxy holds onto it and pulls it around easily.

Even if we harness fusion there is always the problem of being able to contain the reaction. You are after all causing 2 particles to "FUSE" into a single particle. The amount of pressure and temperature required to do that is so high that you need some serious science to stop the WALLS of what you are fusing inside from doing the same thing...

I am referring to two things here. My teacher said if we were able to, we could use fusion for a lot of things.
And, haven't you ever seen Back to the Future? At the end, the Doc went 30 years into the future and came back with a flying car that ran on fusion :).

Now that'd be nice if we could get some technology like that.

[SteveCRM]

You couldn't go back in time because you aren't really just leaping to another time. You are making your time slow down, to make the time around you go faster. So you don't just appear in a time. Time goes by so you can get there. So therefor you can't go back. Because time is always advancing. So unless we find a way to actually stop time going into the past is still science fiction.

[Sam Finch]

Matthew, I think the car in question ran on fission, In fact it must have because at the begining Doc was staeling plutonium from terrorists to make his car go, and plutonium is used for fission, not fusion, if you fused 2 plutonium atoms you would get less energy than you started with.

In any case he got it running on steam in part III, the only reason they used the nuclear fission was to get the car up to the inconcievable speed of 88 miles per hour.

The Idea of Cold Fusion (allowing Fusion to take place at temperatures less than those of the Sun. Is Theoreticly possible, and could lead to some great things, but not time travel.

Steve

The Idea of Going back in time is again theoreticly possible through something called a worm hole, this would involve somehow bending spacetime back on itself untill there's a little tunnel back to a different Time, But as Stephen Hawkin Points out If time travel is possible why has nobody come back to visit?

[Hani2000]

If internet was like Space, then there will be a second when everything shrinks and keeps shrinking until it is gone, and all that happes in a millisecond!!!

[Zaphod64831]

Originally posted by Matthew Gates
In the 1st, 2nd, and 3rd dimensions, we have up and down, left and right, and three-dimensional. What is the 4th dimension?

Ah, one of these few questions that I can answer. The fourth dimension is time. One of the things that is different about this dimension is that it is constant at it's rate and it is what all the other dimensions are based upon. I have a whole crapload of stuff thought up in my head to explain this but I don't want to run the risk of overdoing it or flood someone's browser, so if you want to know more just say so.

[Sam Finch]

I'd quite like to hear it, by the sound of it you may not have taken Special Relitivity into account, but it could still be interesting.

[Zaphod64831]

Ok, so it isn't quite as large, but I had to shorten it a bit as I'm writing this from work and I'm a little given to hyperbole. Otherwise I'd also include some of the deranged theories that I've come up with after a long day of getting a high off caffeine and being up at 6 in the morning.:)

The first three dimensions are partially based on the fourth, but only in movement not in existence. If time were to freeze at this very second all of the first three would still exist, yet there would be no movement through them. From this simple fact (or something closely related) we were able to come up with rate.

Rate is determined by the speed at which an object's place in the first three dimensions changes between two points in time. These distances can be measured in several different ways, using systems such as the metric and standard. The times may also be different, but usually they are hours (unless you are an astronomer, where the main distance is a light year and the time is a second).

The reason I say that time's rate is constant is because according to Einstein's Theory of Relativity time is relative to the observer, and the observer observes time at a constant rate. Thus making time constant. I have no doubt that we will soon be able to more accurately study time and its properties later on, possibly even leading to travel between two points on this fourth dimension.

[Gen-X]

You cannot say that time is "constant" and then say that it is "relative to the observer". Thats a contradiction.

Now you can say that time is "constant to the person measuring it" because that agrees with the second statement.

If we take time as being "relative to the observer" then doesn't that mean as an absolute truth "time is NOT constant"???


As for Steven Hawkins asking why people haven't already come back from the future how do we know they haven't? Its our "present" and as such anything that happens is to us the first time it happened. If someone came back and told us then we would change the future and the person wouldn't have come back (possibly) so we end up in a paradox.

Either that or they have a temporal prime directive that says they aren't allowed to go back to "primative" timeperiods ;)

[zmerlinz]

hi,

the way that space expands (are we sure that it is expanding ?) is similar to Fractals (the chaos theory) they are patterens that continue infinitley in infinite directions, (are you still with me ?), then this should really account for the fourth dimension, or in this case the I Dimension where I is Infinite, (hence the label, chaos theory)

Merlin ?

[Zaphod64831]

Yes, we are sure it's expanding, sort of.

Science believes that because the stars are becoming a bit more red-shifted (or was it blue?) they are moving farther apart. This coincides with the Big Bang theory. But I don't quite see how an already infinite expanse can expand. I can see the suns and galaxies moving farther apart, but to say that that means the entire UNIVERSE is expanding just doesn't make sense to me.

[HarryW]

9.8m/s² is the acceleration due to gravity, g.

This value is, as stated, dependant on the mass of the planet, due to the formulae

F = G(m1)(m2)/r²

where G is the gravitational constant, m1 and m2 are the masses (you and the planet) and r is the distance between the two centres of mass.

Since F = ma (Newton's Second Law),

a = F/m
(g = F/m)

So, a = Gm2/r² (since m = m1, they cancel)
or g = GM/r² (where M is the mass of the planet)

That's where the value of g comes from, although in actual fact it differs slightly depending on where you measure it - The earth is an oblaque spheroid, so r is greater at the equator than at the poles for instance.

A body will not accelerate at exactly the same rate as the value suggested by the formula, even if it's in a vacuum, because unless it is exactly on the axis of the earth's rotation then it will have a centripetal acceleration also.


I think I read somewhere once that if 14% of Jupiter's hydrogen was mined and made into fusion bombs, then, if a series of such bombs was dropped behind a spacecraft in such a way that the spacecraft was not damaged but was accelerated, then said craft could achieve a velocity of approximately 1/3 c. That's a lot of Jupiter though ;)


It is, according to relativity, not possible for any massive body to reach the speed of light, since that would require infinite kinetic energy. I should think that a fusion reactor would produce enough energy to achieve a significantly high velocity, the weight of the reactor could be easily counteracted. It would require much more energy to achieve higher velocities though.


The most viable fusion reactor I have seen is a torus, which contains the fuel gasses as plasma circulating around the torus, contained by strong electromagnets around the torus to keep the plasma away from the sides of the reactor. There are still problems at the moment. So far we even need fission bombs to get enough energy to start a fusion reaction in a hydrogen bomb, I'm not sure how they propose to inject enough energy in the first place to get the fusion reaction started.






[Edited by HarryW on 07-12-2000 at 01:13 PM]

[Sam Finch]

Merlin

So you try to confuse me with fiction he, Watch and wonder as the Confusee confuses the confuser using merely the facts.(and maybe some brackets.)

Let's Start at the Start, (for as I say (and say Well) I am using nought but Facts and Brackets, (Starting at the end would be unnecessery(and unfair))) Think of 2 boxes, each with lots of apples in them, your job is to check that both boxes have the same number of apples in them, you have 2 empty boxes to aid you. What's the best way of checking. Easy, you take one apple from each box and put it into one of the other boxes, making sure all the apples from one box go into one empty box and all the apples in the other go into the other. You keep doing this one pair of apples at a time until one box runs out of apples, if there are the same number of apples in each box then both boxes will be empty, if there are not the same number in each box then one of the boxes will have some left over. and vice versa.

What did we actually do here, we proved that if we have2 sets of objects and we can match each object in set A with a unique object in set B with none left over Then Set A and Set B have the Same number of Things in them, or more usefully.

2 Sets A and B have the same order(number of elements) iff each member of Set A can be mached with a unique element of set B and each element in set B an be matched with a unique element in set A Hope you're with me so far, this is the easy bit.

Now Let's imagine 2 Sets with an infinite number of elements, let's say the Set of Natrual Numbers(1,2,3,4,....) (call this N) And The Set Of Even Numbers,(2,4,6,8,....) (Call This E) Which has More elements? E you Cry E, But Let's Put this to Our Test,

Every Element In N Can Be Matched With A Unique Element in E, and Every Element in E can be Matched with a unique Element in N. (1,2) (2,4) (3,6), .... (N,2N).



What About Fractions, Surely There Are More Fractions than Whole Numbers,

Every whole Number Definatly Matches With a Fraction, a whole number N Matches With N/1.

But What about Matching the Fractions With whole Numbers

Let's write Some Code

Public Sub ListFractions()

Dim i As Integer
Dim j As Integer
Dim n As Integer

i = 2
n = 2

MsgBox "1/1 Matches With 1"

Do While True

For j = 1 To i - 1

MsgBox j & "/" & i & " Matches With " & n

n = n + 1

MsgBox i & "/" & j & " Matches With " & n

n = n + 1

Next j

MsgBox i & "/" & i & " Matches With " & n

n = n + 1
i = i + 1

Loop

End Sub If We Pretend There's not Going to be an Overflow Error when VB runs out of integers, then Ther is No Fraction We Won't Get Eventually Matched up to a unique whole Number.

So there are the Same Amount of Whole Numbers as there are Fractions.


There aren't very many numbers left, How about Irrational Numbers, These are numbers that Can't be expressed as Fractions, They are infinite Strings of Decimals that go on forever without Repeating, like pi or sqr(2). Are there more of These than there are Whole Numbers?

[you - No, I'm Sensing a pattern here, you're going to find a clever way of listing them all]
[Me - Wrong , Ha Ha Ha Fooled You, There's no way of listing them all]
[you - Proove it]
[me - I'm glad you asked]

Imagine I found a way of listing all the irrational numbers between 0 and 1.


1 - 0.45789274894209347207937394720......
2 - 0.89024652934520349572034572394......
3 - 0.03462945239475620873456023456......
4 - 0.34987234785203456238452346529......
5 - 0.34753745629834562934759232373......
etc


OK, now I'm going to think of one that's not on the list, take the first digit of the first number(4) and add 1(5) now take the second digit of the Second number (9) and add 1, in this case it's 10 so we'll make it 0, then the 3rd digit of the 3rd number and keep going for all the numbers on the list (you won't reach the end of the list but there's an infinite number of digits so we can match each digit with a number on our list.

so we get the number 0.50594........

it's not the first number because the first digit is different, it's not the second number because the second digit is different, it's not the 3rd number because the third digit is different, and so on all down the list.

So whatever way you find of listing the irrational numbers I can show you a number you've missed out. So there are more irrational numbers than whole numbers.


So What about the Numbers between 0 and 1 and all Numbers(Rational and Irrational (including -ve ones) Are there more irrational Numbers in total than there are between 0 and 1


Of Course, take any number between 0 and 1, subtract 0.5
take the inverse and then if it's +ve subtract one, if it's -ve add one, there we go, every real number has a unique partner between 0 and 1. and Vice Versa.

Now, Any Point on a line Can be Identified by a Number the Distance From it's end, Or the Distace Form a particular point if it's infintely long. So the number of points on a line Is always the Same, No matter How Long it is.

A Line is a one Dimension al Space. I Can't remember the proof but there are more points on a plane than there are in a line, In Fact.

There are more points in an x dimensional Space than there are in a y dimensional space iff x>y

It can also be shown that

any 2 x Dimensional Spaces Contain the same number of points and for any 2 spaces containing the same number of points if one is x dimensional so is the other


Now we've got that sorted (there'll be proofs somewhere on the web if you're desperate) we can Go on to what a Dimension is.

Take an X Dimensional Object, transform it so that you can split it up into n Equal sized pieces all the same shape as the original (for example a square can be split up into four smaller squares.

Now, Measure the length of one of the Sides of these objects (If it's a square take one of the sides, a cube one of the edges etc) find the ratio of the same length on the original shape / the new length

Eg if you split a square into 4 small squares the original sides will be twice the length

so for the squares the ratio of the sides is 2 and the shape was divided into 4 pieces

. take natrual logs of both sides and divide the 2 to get the number of Dimensions

NumberOfDimensions = Log(NumberOfPieces) / Log(RatioOfLengths)


This Is How We Define Dimensions
OK, That's Enough BackGround, Let's Look at Fractals and Why They're nothing like the universe.


Let's look at a very simple fractal, A Spvenski Gasket (I don't know If I spelt it right)

Start a new project, Add a little Command button to your form, and a Text Box, set the AutoRedraw Property to true and text1.Text to 5

now add thisOption Explicit



Private Sub DrawGasket(x1 As Single, y1 As Single, theta As Single, Length As Single, depth As Single)
Dim x2 As Single
Dim y2 As Single

x2 = x1 + (Length * Cos(theta))
y2 = y1 - (Length * Sin(theta))
Form1.Refresh
DoEvents
If depth = 0 Then

Form1.Line (x1, y1)-(x2, y2)

Else

Call DrawGasket(x1, y1, theta, Length / 3, depth - 1)
Call DrawGasket(x1, y1, theta + 1.0471975511966, Length / 3, depth - 1)
Call DrawGasket(x1, y1, theta - 1.0471975511966, Length / 3, depth - 1)
Call DrawGasket(x1, y1, theta, Length / 3, depth - 1)

End If

x1 = x2
y1 = y2
End Sub

Private Sub Command1_Click()
Form1.Cls
Form1.ForeColor = vbBlack
Call DrawGasket(0, Form1.Height / 2, 0, Form1.Width, Text1.Text)
'Form1.ForeColor = vbRed
'Call DrawGasket(0, Form1.Height / 2, 0, Form1.Width, 1)
End Sub

Hit the CommandButton, and You Get a Gasket, If you wanna make the form big you can increce the number in the Text box for more detail.

Now Imagine it in infinite detail, the Closer you zoom in on the Line the More detail you get, following that set pattern.

Now You Can Divide this shape into Four Seperate Bits of the Same Shape (UnComment the Commented lines and you'll get some red lines to help.)

So, If We Divide the Shape up into 4 pieces each one 1/3 of the Length of the Original from end to end.

this gives us Log(4)/Log(3) = 1.2618595 Dimensions?

As you can See, There's not as many points as in a plane, But More than in a line If you tried to map all the Points in it onto a line, you couldn't. In Order to beable to get all these points into the 2D Space you Have to Leave a lot of Space but it must be to Complex to be a line, to accomidate this exta part we need it to be infinitly Complex, The Universe isn't infinitley Complex, It's Very Complex But not infinatley, which makes it Exactly 3 Dimensions (Or 4, 5 or 10 depending on what book you read I use 3 because it's easier to visualize)
This is why the Universe is nothing like a fractal And You know what A Dimension Is And What A fractal is. (if you Look at the About Creation and AI and Evolution For those who Care threads between me and Gen-x you'll se why I think it's neccesery to get the big guns out first on the Dimension issue)


Zaphod, When We Say the Universe is expanding it means that all the Stuff in it Is Flying appart, The Space itself isn't expanding, and the Universe Isn't infinate as such, but it is flying appart at the Speed of light at the edges so we can never get to nor see the end, so for all intents and purposes it is infinite, but there's only a finite amount of stuff in it.

[Sam Finch]

I am the master of clarity, your head is too full of fog to know when you are confused or not. I have told the wind to blow through your ears to dispell the mists of mistery

[HarryW]

I just had a thought:

If the edges of the universe are travelling away from the origin of the big bang at the speed of light, and photons are massless, then how would the energy contained within them ever return for another big bang (as per the closed universe theory/theorem (whichever it is))? Although they can be affected by the EM force, the guage bosons of the EM force are photons, so they would not catch up with them. If I'm wrong and there is a restrictive force acting upon them, then what about neutrinos, whose rest mass is believed to be zero, and are only affected by the weak force which has limited range? (some GUTs suggest the neutrino may have non-zero mass)

If this was the case, then wouldn't that mean that the universe could not have been in existence for infinite time, since all the energy would have been dispersed?

[zmerlinz]

hi, Sam

i shall conteract your wind with littening to strike confusion to the very depths of your heart and soul


Merlin ?

[Sam Finch]

Harry

It's A Good Point, I Don't Fully Undersand The Physics Behind Must of these Theories, but I Think it's something to Do With The Idea That When A Gravitational Field Changes You Don't Get Instant Effect Everywhere, so You Can Imagine The Change Spreading out Along the Universe, This Is a Little Bit like a Wave, and as we all know waves and particles are the Same thing so they manifest themselves as Gravitons. This would just mean that the Photons at the Edge of the Universe are acting under the Gravitational field of the Big Bang itself, eg the whole universe as a point mass, so they would be pulled in.

Merlin

Ha I've got My anti Lightnig Boots On, I've magiced up some books on "Life Made Less Confusing" and a Man with a big stick to force you to read them.

[HarryW]

If photons are massless, though, then I don't see how they could be affected by the gravitational force, especially since photons are the guage bosons of the electromagnetic force.

Another thing I was thinking, though, is that the speed of light is said (by Einstein I believe) to be constant relative to the observer. Could a photon be considered to be an observer?

I don't fully understand the way something this complex works, for instance is it actually possible to decelerate a photon? The speed of light is constant after all. But then light cannot escape a black hole, so it must be either decelerated or bent by the gravitational field. But that means that the gravitational force is acting on a massless particle (or wave, whichever way you want to think about it). I think this must be something to do with bent space, something Gen-X mentioned earlier, in which light always travels in a straight line, but the way space is bent means that that straight line is itself bent and therefore perceived to be curved.

Clearly, this is difficult to explain, but do you see what I mean? Is it possible that this bent space could alter the path of photons at the very edge of the universe?

[zmerlinz]

HI, sam

does this man have a long grey beard, and a little crystal on top of his stick (no rudeness intended)

Merlin ?

[Sam Finch]

Harry

The Trouble With Questions like thyese is the more that get answered the more you can think of, I'll give these ones a go.


If photons are massless, though, then I don't see how they could be affected by the gravitational force, especially since photons are the guage bosons of the electromagnetic force.


Under Classical(normal) Physics Light isn't affected by Gravity, It was never observed to do anything else until Einstein predicted that it should and he set Up his Faous Experiment. (I can't remember what it was called but he pointed out that a certain star would be hidden by the sun at one point and 2 images of the star were observed because the light bent round it) Essentially in Relitivity the Concept of mass is meaningless, as you say later photons go in a straight line and space itself is bent, I don't claim to be able to undersand it fully, If you just imagine rolling a snooker ball round a rubber sheet with large objects on and seeing what path it takes.

Another thing I was thinking, though, is that the speed of light is said (by Einstein I believe) to be constant relative to the observer. Could a photon be considered to be an observer?

Yes, Is the short answer, If you do all the maths taking a photon as an observer then you see the photon at rest and everything else going at light speed in the opposite direction. (everything, including other photons, unless they are going parallel to the observer.

The Maths isn't that hard for this, there's 2 speeds for every object, a speed u which is the speed you would expect something to be doing if it weren't for reletivity, and an observed speed v which is the speed you observe it to be going. there is a formula u = F(v) which get's the observed speed from the expected speedu = Sqr(((c * c) * (v * v)) / ((c * c) + (v * v))) and to get the other way round usev = u / Sqr(1 - ((v * v) / (c * c))) if you plug an observed speed of c into the equation you find u to be infinite, this means that because the expected speed is infinite you can never reach it, and if you have something going at that speed and you try to decellarate it you get infinity - x = Infinity, plug that back in you still get the speed of light.

Trying to imagine relitivity getting out of a black hole you have to imagine it as a wave, a wave has a certain amount of energy, calculated from it's wavelength, the less energy it has the longer its wavelength, so as it get' sout of a black hole it's wavelength gets longer and longer until eventually it becomes infinate then it flips round and befomes -ve, this means it is travelling in the opposite direction(imagine the graph y = 1/x, going form 1 to -1 the number gets bigger and bigger then becomes infinite and goes -ve, every point has a value except 0, this is what's happening to the light)

That's the very very basics, I'm sure this will spring more questions and I probably won't be able to answer them, If you get a book about special Relitivity you should be able to understand the maths (If you can sole a set of 4 Simultanious equations you can do Special Relitivity, it's just gravity that makes it hard)


Merlin No, He's very big and very hard and has "I hit people with sticks unless they read the books I give them" Tattooed on his forehead.

[HarryW]

So under relativity, photons are affected by gravity. I see. I've done some particle physics so I know a bit about basic relativity, but I'm not sure if I can solve that kind of equation you mentioned. Could you give an example please?


Btw Sam, do you understand general relativity?

[zmerlinz]

hi Sam

Oh i am scared now, i bet that he has a tatoo saying "i love Mum" in a heart shape on his arm, i have a Dragon that eat men like yours for breakfast, and also if you annoy him he will blow red fire at you and eat you as toast.

Merlin ?

[Sam Finch]

I do Special Relitivity, I've not studied General Relitivity though, I think I get the General Principal, The Idea is that you assume the laws of special Relitivity and then assume that there'a no difference between going in a straight line at a constant speed and falling freely under Gravity, Then You do some hideous maths and you find that every point in spacetime has a gradient, this Gradient has no units (ie it's a length divided by a length which is a ratio) and you have to introduce another Dimension along which space is curved.

Do you mean you want an example of a set of 4 simultanious equations? basicly imagine a set of equations like this



X + 2Y - 3Z + 7T = 6

3X + 4Y + 4Z - T = 18

7x + Y + Z + T = 12

X + Y + Z + T = 6

the solution being X=1,Y=2,Z=2,T=1
you should be ablt to write a program t solve any set of equations like that.

If you can do that you won't have any problems with Special Rel, If not, try a set of equations like this

X +2Y = 3

3X - 4Y = 4

the answer is X=2, Y=0.5

If you can do that, look up a Topic Called Linear Algbra, That'll get you to set's of 4 quite quickly.

[HarryW]

Oh right, that doesn't look too hard then, just do some substitution and stuff. I've done A-Level maths so I can do that I think.

[Active]

Originally posted by Sam Finch
Harry

Yes, Is the short answer, If you do all the maths taking a photon as an observer then you see the photon at rest and everything else going at light speed in the opposite direction. (everything, including other photons, unless they are going parallel to the observer......


So, Is that..

Einstein's Prediction that nothing having a mass can reach the velocity of light is not valid when you consider a Photon as an observer???

Active has been doing some archeology off late :D

[Sam Finch]

Mass is a bit of a funny concept in Relitivity and Quantum Mechanics, it doesn't mean the same thing as in classical physics.

There are actually 2 sorts of mass.

Gravatational Mass (or rest mass.)

This is the mass that dictates gravitational pull, it is constant no matter the velocity of the object.

Inertial Mass
This is the objects momentum divided by its speed, which dictates how much force is needed to accelarate the object. As momentum is a vector and speed is a scalar the objects inertial mass is also a vector.


A photon has a rest mass of 0 (but they can never be at rest, or any other speed other than c) so they can go at the speed of light. As they have no gravitatial mass and no inertial mass perpendicular to their velocity they can be affected by gravity, but only in one plane, using the laws of clasical physics to determine their accelaration under gravity we get the indeterminate form 0/0. And so we must use General Relitivity to predict their movements.

[HarryW]

This is one of those beard-strokey concepts.

[parksie]

This also way over my head :( But I'm almost catching up :)

[Active]

Well thanks for that.. but i have a real basic question
de-stabilizing the foundation of my understanding on relativity.

Is there any mathematical or a theoretical proof for
light should have a constant velocity relative to an
observer.

I don't think Michelson-Morley experiments and the practical experiments that followed are the
only supporting factors for this principle of relativity.
So where can i find a Mathematical treatment for the
same..any links you recommend ??

I read Stephen Hawking's Brief History of time...but
he just says in one line that...

"All observers in relativity must agree on the same
speed of light "

I could understand the Relative Space concept...
But to understand that time is relative...I have to
clear this doubt on the Constancy of Speed of light
relative to an observer independent of the velocity of
the source of the light.

Hope you could help me ! :)

[Kzin]

Originally posted by Active
Well thanks for that.. but i have a real basic question
de-stabilizing the foundation of my understanding on relativity.

I don't think Michelson-Morley experiments and the practical experiments that followed are the
only supporting factors for this principle of relativity.
So where can i find a Mathematical treatment for the
same..any links you recommend ??

Hope you could help me ! :)

I think what you are looking for are Maxwell' equations - try http://www.britannica.com/eb/article?eu=119361&tocid=69308 for an introduction.

As you say these theoretical constructs are backed up empirically and robustly up by the Michelson-Morley Experiment - if you can find a hypothesis that explains the absence of the Aether Wind better than the equivalence of all inertial frames I'd be keen to hear more -
http://galileoandeinstein.physics.virginia.edu/lectures/michelson.html [updated link I put in earlier was an old broken one]

Anyone who wants to catch up of why active asked this question start with
http://www.phys.virginia.edu/classes/109N/lectures/spedlite.html before reading the above

[Kzin]

Originally posted by Matthew Gates
In the 1st, 2nd, and 3rd dimensions, we have up and down, left and right, and three-dimensional. What is the 4th dimension?

About a hundred and twenty years ago a British math teacher Edwin A. Abbott wrote a book to help schoolkids (and anyone else really) to understand and manipulate concepts in higher dimensions. Its written as a sort of tongue-in cheek adventure story and is very easy to read and follow. The quaint little tales are designed to make the intelligent high-school age (and above) reader think through the issues involved in different dimensions

It is called Flatland and you can find a copy on http://sailor.gutenberg.org/by-title/xx548.html

[Active]

Wow..Kzin the Links are really Wonderful...

Just 5 pages more and I am Sure I 'll come back with
a better Understanding !