posted 07-06-99 10:32 AM ET        

Anyway, around 12 o'clock somehow we got sidetracked and started talking about what god actually was, were he was, and how he got there. NOTE THAT I'M NO AThEIST. These are the following theorys we developed:
My THeory on GOd Himself:
God is not a "being". He is actually a theory of everything, or the guiding theory that governs the other theories.
The actual creation of god was probably by some ancient king (or queen) who's people lost faith in him so he gave himself powers and things of that sort and said he was a "god". THen from then on people made stories up surrounding this god that made him the creator of everything.

I punched a whole the size of Michigan in the idea that god is a being by bringing up a simple law of physics--"Matter can neither be created nor destroyed in the universe" (this theory can not be correct anyway becuase things do not last forever and they do not stay for infinity, because our simple minds can not process infinity)

SUMMARY: god is the law of everything and nothing. All other laws are subdivisions of the god law.
--------------------------------
Also on the topic of time travel:

1. We know it wasn't done before because someone would have remembered seeing someone else pop into existance. That and how would we remember the past when it changed because of us seeing that figure pop into existance?
2. When we do develop timetravel there will be no way to reach foward to the time you traveled from because you have two bodies, one in that time and one in the future (during timetravel) when you went to go back to the future your transmitted form would be destroyed, it wouldn't be able to link through from time to time. (If you did make the link you would go catatonic and therefor go insane.)

posted 07-06-99 11:14 AM ET         

Matter can neither be created nor destroyed in the universe
I think this is meant to be understood as matter and energy being essentially the same thing. Sure the matter may seem to be created or destroyed, but in fact it has merely changed from one form to another.

You time travel argument is supported by Steven Hawkings. But I'm uncertain it holds water. It assumes you can interact with the time you have moved to. It also assumes that there would be a sufficient number of folk visiting this time that failed to keep themselves out of the public eye.

Didn't understand why you thought your transmitted form would be destroyed. It implies you think that the 'same' atoms can not exist in two places at once. Which is quite an act of faith.

posted 07-06-99 04:33 PM ET            

Oh, and when i say being i mean something that exists that is wholly or partially tangible.
And my freind veiws god as living in the fourth demension (time).

Wait, i made a mistake. You wouldn't be able to go into the future because your body would not exist. Non existance mean you would be destroyed.
Time Travel is pointless anyway because if you traveled back in time to chang one thing it would change everything in the future and you wouldn't remeber traveling in time because you didn't in the past but did in the future and the future hasn't been lived yet at that time in the future you came from. Therefor if you didn't timetravel when you lived your life from the past your changes would be "offset" therefor you would be stuck in a "loop" of time.

posted 07-06-99 04:41 PM ET            

If matter is eternal, why can't God be?

This is an non-christian taking turns at being devil's advocate. I'm interested in how the theories turn out.

posted 07-06-99 09:05 PM ET            

Physicsts (I cant's spell for ****) already belive that they can travel backwards in time. It would involve travelling to a black hole and causing it to spin. The two main problems are, it would take an enormous amount of energy, both to get there and to set it spinning and you would only be able to go back to when you first set the black hole spinning.

Einstein also theorised that if you travel faster than light in "normal" space you will go backwards in time. But Einstein is a jackass anyway. If time was the rigid thing they say it is, how come some people can see the future?

I'm saying this because sometimes I can see the future. I once saw a lottery ticket in a dream. I took note of the numbers and played them and they won. The week after I played them! I should have taken note of the date on the ticket as well!

The faster than light/back in time theroy is an expansion of the "twins" theroy. You know take one twin, put him on a space ship and fly him around the earth at the speed of light for a year, bring him back and his twin will have aged 100 years, or something like that.
Total bull****. The first twin would be very dizzy and have travelled a long long way but his twin would still have aged only one year. Why would time suddenly slow down at the speed of light? It doesn't slow down at Mach 1, Mach 2, Mach 3. Why would it slow down at the speed of light?

posted 07-06-99 09:14 PM ET            

If matter is eternal, why can't God be?
No reason at all. It doesn't matter what the laws of the universe are when you argue the existence of God because God is not part of the system. There will always be people who believe in God(s).

By the way, I think the concept of infinity certainly is comprehendable. Sure, we can't witness infinity because our lives are finite but what is so hard about understanding infinity??

(Where is Octopus!?)

posted 07-07-99 01:10 AM ET            

5 Time Travel possibilities:

1)If you traval backwards into time, you might create a parallel universe.

2)A rift in the Space-Time continuim might simply destroy the universe as we know it.

3)Your existance will travel backwards, but your body might stay in the same palce. Your spirit will hover out the past surrounding totally oblivious to other human eye. It has to be this way in order the keep from changing the past slightly. Even a slight change can lead to a drastic one.

4)You can see what happens when traveling back in time by traveling back 5 minutes to see yourself traveling back into time. Once these 5 minutes are up, there will be one true you and the other ceases to exist. Plus, if you are planning to travel in time and you suddenly see a horribly mutated self appearing in front of you, you'll change your mind. At the 5 minute mark, the mutant you will cease to exist becuase you never left this time.

posted 07-07-99 01:49 AM ET            

Who made God, anyway? Does He have a conscience? If so, I'd hate to be Him.

Einstein was wrong about the theory of relativity. It totally clashes with quantum mechanics, which is a correct theory. And E=mc^2 means energy=mass times the speed of light squared. BUT, Einstein himself said that nothing can exceed the speed of light, right? So the speed of light can't be squared, because nothing can go faster than light, sez Einstein.

posted 07-07-99 05:17 AM ET            

quote:

---

"Einstein was wrong about the theory of relativity. It totally clashes with quantum mechanics, which is a correct theory. And E=mc^2 means energy=mass times the speed of light squared. BUT, Einstein himself said that nothing can exceed the speed of light, right? So the speed of light can't be squared, because nothing can go faster than light, sez Einstein."
FauxCujo

---

That must be a joke right?

posted 07-07-99 07:01 AM ET            

"What would happen if you were traveling in a spaceship going at almost the speed of light, say, the speed of light minus 10 mph, and shot a bullet forward? Wouldn't the bullet exceed the light barrier? What if you ran forward and are healthy enough to do 11 mph?"

HA ok a quick physics lesson
1) the galaxy is not stationary
2) the universe is not stationary
3) speed is relative
this means that a concorde travles at 700 km/h is this the speed of the plane...
BULL**** it is. the earth rotates at 64,000
in addition the galaxy rotates and the universe keeps moving in summary a concord may only seem to be moving at 700 km/h but is is traveling at >64,700 km/h you could be travelind at 10 mph slower than C according to your view point but you wont be
it is impossible to travel than the absolute C but that doesent mean you cant appear to
My Example 2
2 space ships travling in opposite directions at exactly 1 mph over 1/2 C from the two cockpits they are moving away from each other at C + 2 mph are they breaking the laws of physics

any way FTL travel is possible just use wormholes

c u all later

posted 07-07-99 07:58 AM ET            

i'm sorry if i have done a bad job of explaining this but i am only 19 yrs old and it was explained to me a few years ago

posted 07-07-99 11:15 AM ET            

However, Quantum Mechanics did not replace Eintsteinian Relativity.

Quantum Mechanics is wood, classifying everything by breaking it into tinier and tinier bits...eventually, such subatomic particles will be so small and require so much energy to isolate, it will prove impossible to fully "define" the fundamental building blocks of the universe.

Special Relativity is marble, simplifying everything into a simple and beautiful equation. However, it cannot unify all of the principle forces of the universe in the four dimensions in which it exists. It cannot factor in gravity, while it is able to factor in the other three (strong and weak nuclear force and electromagnetism).
Then, there is the Grand Unification Theory, which seeks to unify the four primary forces in higher dimensions. This has yet to be sucessfully proven mathematically.

posted 07-07-99 12:02 PM ET            

Question: Why bad things happen to good people?
Answer: "Well, my son, it's god's will"

Question: Why bad things happen at all?
Answer #1: "God is testing you"
Answer #2: "It's Devil's work, my son"

Question: Why do people kill other people over religion/god?
Answer: anybody?

Question: Why doesn't god show himself?
Answer: "You can't ask for proof, you must believe in him son."

So...
Time Travel: nope
God: probably not/maybe/hope so

"Since you die from the moment you are born, don't take life too seriously, because nobody ever get out alive."

posted 07-07-99 12:24 PM ET         

Question: Why bad things happen to good people?
Answer: So that they may learn and advance from the experience.

Question: Why bad things happen at all?
Answer: See previous answer.

Question: Why do people kill other people over religion/god?
Answer: Because they have a lot to learn before they act correctly.

Question: Why doesn't god show himself?
Answer: Because it would ruin your opportunity to advance via experience in this life.

posted 07-07-99 12:45 PM ET         

I've changed my opinion of such things at various times in my life, so when I say I'm fairly certain now, maybe in ten or fifteen years time I will have changed my mind again. But I hope not.

They arise from trying to make sense of everything. The big weakness in that is there is no guarantee that everything is supposed to make sense.

posted 07-07-99 05:13 PM ET            

The answer to most of this for those not inclined to take things on faith is "not enough evidence," although a good alternative is, "it depends upon how you look at it."

posted 07-08-99 01:22 AM ET            

Wait... What you're saying, M_ashwell, seems to be that speed can't really be measured because it's all relative depending on the observer. Now, I know that, but how can light break this rule? Does this mean that if you travel at C minus 1, the speed of light is still six trillion mph or whatever faster than what you're doing, or what you appear to be doing... Crap.

And by the way, I hear light travels around six trillion miles in a year, so about how fast is that in mph? School's out for summer, and my brain is still today, so I'd rather not do the math.

If, as you say, the universe isn't stationary, what is it moving through? How can there be absolutely nothing, or LESS than nothing, around the universe? By "not stationary," do you just mean it's expanding?

posted 07-08-99 04:28 AM ET            

If you would fall into a hole (we're talking Einstein) the time would become so 'streched' fo you that you would falling into it forever.

posted 07-08-99 08:32 AM ET            

(186000mi/sec)*(60sec/min)*(60min/hr) = 669,600,000 mph

posted 07-08-99 12:25 PM ET            

Neither General Relativity nor Quantum Mechanics can. Special Relativity doesn't even take gravity(or accelerating frames of reference in general) into account at all.

posted 07-08-99 03:54 PM ET            

My theories:
GOD:
It isn't a being, it is a theory of everything, or a governing theory of the universe. Some Psycho king made the being up. It is just the theory the says the other theorys exists. IT GUIDES THEM. therefor they're is no "tangible god" just a theory amplified to a human. Think a little that humanity always wants things to relate back to itself--therefor for some reason, we think "god" is human. This is really stupid because humanity IS NOT THE FIRST FORM OF LIFE IN THE UNIVERS(S). Even saying they're is a tangible "being" god is sorta crazy. It is probably just the energy.

TImE TRAVEL:
To amplify what some of you are getting so close too:
Lets say one human (1) goes back in time and kills one flower (1). Know we all know that one flower (1) probably has around a few hundred thousands seeds (100,000) that it sends out. Now lets say that about five thousand (5,000) of these seeds actually become flowers. So: when you return (if you do) to the present (or in the future) there will be 5,000 less flowers, there for thousands less bees, therefor thousands less of the things as you go up in the food chain.
SO:
You would pretty much ruin (sort of) time.

posted 07-08-99 04:09 PM ET            

Somewhere, I did come across the answer to this conundrum, but I've forgotten it. Can someone refresh me?

posted 07-09-99 02:37 AM ET            

Again blackholes... How can you travel through the time by spinning the star (with souch incredible mass and gravity that have collapsed into it self, but stil a star) on the other side?

By the way, how can we create a wormhole?

posted 07-09-99 05:59 AM ET         

Noisy: I don't believe that the universe is infinite. I think this is the most popular view amongst scientists at present. But even if it were there would be two reasons I can think of, off the top of my head, why the sky wouldn't be full of light. (Well one actually, but bear with me.) If there is dust etc. in the universe then it could block the light reaching you. "Ah" you say, "but given sufficient time the dust would gain enough energy to glow and so no longer stop the light", which would be true if the universe was infinitely (or very) old : which brings me on to the second reason. There may not have been sufficient time to allow all the light to reach Earth, making it infinitely bright, and infinitely hot. So this tells us something. Either the universe is not infinite, or it is not infinitely old, or both.

Spider: Yes that is another possibility.

Darksider: Ah in the 'new' timeline they may find that they decided to go back on a whim, and by some lucky chance (although we know luck had little to do with it) found there was something they needed to do, and did it.

Oh you don't need to be able to explain everything about everything for a theory to be considered credible. Inevitably it is done by making a best guess, testing it, changing your guess, until you get nearer and nearer what appears to be the truth. Anyway we're all weirdos here

ZyXEL: Run that by me again ? Is this a variant on the usual "killing your own forebear" paradox ? You can retreat to the multi-universe theory to avoid that one, but otherwise, if you do something to screw yourself up who is to say that your birth, and the birth of all others who are screwed by your change, are not just removed from the timeline ? I stated in an earlier thread of this nature that it is only us more cautious folk who are left !

Tolls: Yeah, it is worth searching the net for info on COBE. I read a book called Wrinkles In Time a few months ago. It was similar to a biography of the author during the course of that project. (Biographies are not something I normally go for so I wouldn't have bought it if I had known, but it turned out to be a good read.) Recommend it to anyone.

posted 07-10-99 02:36 PM ET            

Conservation of angular momentum. Just dump a bunch of matter into it with a large net angular momentum and the black hole will spin.

Getting an electrically charged black hole is a similar process: dump of bunch of charged particles into a black hole.

posted 07-11-99 06:48 PM ET            

I read a column called the Straight Dope, in which people write the newspaper and ask the strangest, stupidest questions imaginable about practically anything. (One person asked what would happen if everybody in China jumped off chairs at once.) Somebody said that 20 years earlier, he had killed 57 flies in a mad frenzy. He wanted to know how many flies he prevented from being born. Using raw math to calculate, it turned out that the population from those 57 flies would have covered the earth in bug bodies- but of course, they point out that the vast majority of the eggs aren't going to make it to maturity. Same goes for your flower seeds.

posted 07-12-99 01:51 AM ET            

Sorry, next time I will NOT

posted 07-12-99 01:06 PM ET            

People say the "space" is a "void" of "nothing". but a law of physics (or some science) says that if something has to be everywhere because the absence of something means nothing exists in that space, therefor whatever things are around that nothingness would be compressed together(or something like that).
The mass of nothing is 0, therefor it takes up NO SPACE AT ALL so saying it does is one big contradiction.

ALso--
By my definition of a "void" (an area in which NOTHING exists) space is not one becuase in order for things to be distances apart there has to be something inbetween them. That and that "nothing" exists in a void, yet stars, galexies, etc. exist in this one? It makes no sense.

ANd one more thing--
WE CANNOT COMPREHEND INFINITY because our brains (of yet) quantify everything in numbers of some sort yet infinity is no number it is a state of being infinite (forever).

posted 07-12-99 05:10 PM ET            

Almost, but not quite.
You'd just need to sqeeze it down to its Schwarzchild radius, where escape velocity becomes c.

EchoKnight:
"People say the 'space' is a 'void' of 'nothing'."

posted 07-13-99 06:56 AM ET         

"The mass of nothing is 0, therefore it takes up NO SPACE AT ALL so saying it does is one big contradiction." Sorry, why is this a contradiction ?

Space doesn't need to be filled as I understand it, although in practice it is thought that it will be seething with virtual particles, coming in to, and out of existence. But if we stay with the thought experiment, I believe that these particles can then be ignored.

posted 07-13-99 07:14 AM ET            

I'll try to clarify:
As people see space, they thinks it is a vast nothingness. But there hasto be something there in order for their to be a distance between the stars, galexys, universes. If nothing is there to hold that space (since nothing has no mass therefor takes up NO space) the things on either side would fill the gap of nothingness util there was something to hold them apart.

posted 07-19-99 04:48 AM ET         

"As people see space, they think it is a vast nothingness."

Not convinced that is true. Space can be seen as filled with matter, or empty of matter.
If considering space as a thing/concept/whatever then it is natural to ignore any matter that it may contain.
So if it is thought of as a vast nothingness 'at this time', this shouldn't be extended to draw unwarranted conclusions elsewhere.

"But there has to be something there in order for their to be a distance between the stars, galaxies, universes."

Why ? It is sufficient that space is there. You seem to need matter to hold everything apart. This is not a requirement. Things can stay apart with nothing but gap between them. After all if you surmise that you need some form of matter for some reason, where do you draw the line ? Does it have to be solid ? Liquid ? Gaseous ? Plasma ? Naw... Space can hold nothing, rejoice in the nothingness.

"If nothing is there to hold that space (since nothing has no mass therefore takes up NO space)..."

Did you mean "If nothing is there to fill that space.." ? Space doesn't need holding does it ?

Nothing does take up no space, or all space, depending on your point of view. It has that unusual property, because it isn't matter and therefore can not be subjected to the same rules/limitations. But that is not the significant bit. The significant bit is that space does not have to be taken up. It can just be.

"... the things on either side would fill the gap of nothingness until there was something to hold them apart."

posted 07-22-99 12:48 AM ET            

Next - complete relative universes: God does/doesn't exist. In effect, you are god because you control what is real. But you share the same beliefs as the beings around you, and this brings you to a similar reality.

Next - The universe is big. It is full - there is no where in the whole universe that does not have anything in it. It's just spread very thin in the vacuum.

Next - Edge of the universe? Innaccessible. But if anyone makes it there, just the energy from the big bang slowly slowing, but expanding into true nothing (the space between atoms, except none of the 4 forces exist).

Next - Relativity: to accellerate any object with mass to the speed of light would require an infinite amount of energy (ie, all the energy in the universe). No matter how fit you are, that ain't in you. Kinda makes the whole concept a little less interesting and limited.

Next - preservation of mass/energy: The universe has a fixed amount of mass/energy. it's only the ratio that matters. Mass can be converted to energy, the important thing is converting energy to mass. The interesting thing is:

How will converting mass into energy affect the maximum size of the universe and whether it will expand forever or contract into a big crunch.

But that depends on whether light has mass.

posted 07-22-99 03:19 AM ET            

Me, "Dad, say you had a wish, and with that wish you wished that forks were never invented. But if forks were never invented, what would your wish be? They would be around for you to wish they were never there, so would you get an extra wish?"

Dad, "Um, er, um, ah, let me go get something from the kitchen, yeah, the kitchen" *Dashes out of room*

posted 07-22-99 05:14 PM ET            

To illustrate this, consider a problem that plagues Physicists; point singularities. These occur as distances tend to zero with such things as black holes, electric charge etc.

String Theory tries to avoid these infinities (point singularities) by assuming thet distance is quatised with each quanta being a plank length. With this interpretaion, there no meaning to distance of less than the plank length and thus point singularities nicely disappear.

Now this may seem obvious but what do you mean by time?

(Before you dismiss this question as splitting of hairs or the contemplation of ones navel remember from Special and General Relativity that our intuitive idea of what speed and velocity are not accurate under certain circumstances).

My personal view is that if a theory results in a paradox then that is a sure sign that the theory needs refining. Time travel paradoxes will disappear as soon as a better theory for time/space emerges.

NoMercy
- Who lives in 10, 26 (or possibly 0) dimensions depending on which current theory turns out to be correct

posted 07-29-99 03:33 AM ET         

The way I see it, time falls under the category of "perceived things". Other examples include color and gravity. We know that color is really just a perception of how we see light bent and fractured along the electromagnetic spectrum. Gravity is just there...it has no mass in and of itself and is not composed of anything physical, it is just a force perceived to exist just because it does. Another example is consciousness. These are things that we accept as existing even though there is no real substantial material existence for them.

Time is the same thing. The only reason why we perceive it is because we have created linear frames of reference (ie seconds, minutes, hours, etc). Otherwise, time would just "exist" and not given a second thought about. The act of existing relies on the references of time we have created...there is no measurement for a "moment" or even an "eon" for that matter.

So, what exactly is the "speed" of time. Well, since all "speeds" are referenced against time, could we not also reference time against speed? For example, I can travel 60 miles per hour. Do we not also say we travel 1 minute per mile. See, sometimes we reverse the stereotypical reference.

So, in terms of time travel, lets say t was a moment in time. That means t-x is x units in the past and t+x is x units into the future. That means that every moment in the present will become the past (eventually). So, in order to travel through time, we need to create the perception that we can stay at point t-x.

We know that we can alter the perception of color, as well as the perception of gravity. If the world decides that today is yesterday, is that not travelling through time? It is after all, just a perception.

Okay, enough incoherent ramblings. Time for bed.

CrayonX

posted 08-06-99 01:06 AM ET         

I wish I'd invented this one, but I didn't. Have you heard about antimatter being stuff that has opposite charge to matter and which annihilates (normal) matter when they meet?

Well the theory supposes that antimatter is normal matter but going "backwards in time", and then takes that supposition further.

So take a pair of electrons. If one is going backwards in time it must appear to act as an antielectron, attracting a normal electron (the reverse-time version of repelling it). If you don't believe in going backwards in time you'd call it a positron: a particle with electron-like mass but with reverse charge namely positive charge instead of negative. We've detected these particles and call them positrons. Two perspectives on what could be the same thing.

The cool thing is when you get a positron and an electron close enough (in a laboratory equipped to detect these things) they attract and annihilate one another with a little blast of energy. And the reverse is also, apprently, observable: that certain high energy interactions leads to lots of (short lived) positrons being detectable.

The theory says that the energy you see is the influence that makes the single electron change "direction" in time. Need to hear that again? An electron is influenced by a lot of energy to change direction in time. An observer sees the electron twice up until the even with all the energy happens, then sees neither the electron nor the positron after that. So we didn't see an electron and positron annihilate but a single charged particle change direction.

The theory goes further. The same thing happens to protons. I'm not sure if it extends to neutrons, which can be fabricated from an electron and a proton and some energy for the mass delta. Anyway the theory says that the big bang was a whole lot of these matter-antimatter pairs all changing direction at the same point in time - and with a whopping great energy input to balance the equation. It predicts that each electron must some time meet a positron somewhere (maybe as a big crunch, maybe as several smaller crunches, plus all the messing about in between such as in laboratories, it doesn't matter) and that energy will be involved each time. It predicts this by saying that there was only ever one electron, not heaps of electrons that just *happen* to have the same mass and charge as each other and just *happen* to have the reverse charge and same mass as positrons. Similarly there only ever was one proton.

I don�t know the theory or my particle physics nearly well enough to explain why a proton and positron have the same charge and different mass but I still think it's a cool theory!

Extrapolating, you could predict that any electron-positron pair created in a lab cannot self-annihilate, because every interaction should be traceable back to the big bang or equivalent event in a single continuous stream of "creations" and "annihilations". Or it wouldn't be the same one electron and wouldn't have the same mass etc. A pretty difficult theory to test.

Does this prove/disprove God? No
Does this help answer relativity or time travel? No
Does it support e=mc^2? I don't know (creation of charge might screw with the equation)

But I like it!!!

posted 08-06-99 06:33 PM ET         

You know that the entire point of the universe is for you to exist. You are the only "real person" in the universe and everybody else only exists because you do. They only appear to think because you made them this way. The entire universe is there because you made it that way.

I saw this on some american show, must have been the philosophers version of the Jerry "I am a love child of a turd " Springer show. He claimed this explained how he could see the future - i.e. because he creates it.

posted 08-13-99 07:30 PM ET            

Einsteins theories:
E=mc^2 is used to explain the relationship between energy and mass, which means mass can be converted into energy (like in your standard fission nuclear reactor) and energy can be converted into mass (like in a cyclotron). That all there is to it.

Proving the theory:
E=mc^2 can be proven easily. Weigh the uranium you put in to a nuclear plant, run the plant a certain amount of time, then weigh the waste. The mass defect (loss of mass) will be equal to E/c^2, where E is energy out. It can also be proven with a Michelsen-Morley interferometer (read any book on physics for more on this).

Faster than light:
Relativity theory has nothing to do with things being able to travel faster than c. Squaring c does NOT mean anything travels at c^2, it is only used as a constant of proportionality in the equation. Things can NOT travel faster than light.

Speed of light and applications:
In case you have forgoten, c=300 000 000 m/s, which means 1 gram of mass can be converted into 90 TJ (tera joules). This is the idea of anti-mattered powered engines. Ordinary engines (chemical combustion) generate around 1000 J per gram, so 1 gram of anti-matter is roughly equal to 1 million tons (yes!) of ordinary rocket fuel. Note that anti-matter must be created, consuming equal (in effect larger) amounts of energy that are "stored" in the anti-matter. The advantage of an anti-mattered powered space craft would be the much lower weight, meaning lower consumption of energy to accelerate. With an anti matter engine, accelerations of around g are possible for shorter distances, say to Mars. Getting to Mars in this way would take roughly 4 days.

Definition of universe:
To make things more clear, the term "universe" is is most usually known as all that which is between (and including) those places of mass (stars etc.) that are at the furthest distance from the point of origin of the Big Bang (the center of the universe), i.e. the "universe" is a finite place. The stuff outside the universe is a vacuum. Some people refer to the "universe" as the above definition, but also including the stuff (vacuum) outside. This definition is not usually used (not in physics textbooks anyway), but with this definition the universe is infinate.

Origin of universe:
The origin of the universe (as defined above) is just a mathematical probability, so technically there could be other universes (places with own mass, i.e. other Big Bangs) outside our own. So far none have been spotted (duh!), so these would technically be VERY far away from us (at least 30 billion lightyears away).

Expansion of universe:
The universe is expanding 360 degrees in 3 planes (X,Y,Z), like any explosion in a vacuum. It is expanding into nothing (into a vacuum).

Time travel:
Time travel (both forward/backward) is possible according to many different theories. According to theory of relativity (a proven theory) you can travel forward in time, but not back. Get in your spaceship (equivalent) and travel at a sufficiently high speed, say 0.9c. Your frame of reference (time frame) slows down. Travel back to earth, and other people (with their own time frame, "reference frame") will have aged more than you. The drawback to this is that the human body can not be accelerated much faster than around g (10 m/s^2) (meaning that it takes a long time to get to 0.9 c), chances of collision with other matter (the galaxy is full of stuff) and the energy needed to accelerate is HUGE. In other words, time travel into the future is practically not very usefull. The best way to travel into the future, as I see it, is to (in the future there will be better technology) to freeze yourself, and rewake at a later date. Can't see what this would be good for though, but you could always invest $1000 in the stockmarket, sleep for a few hundred years, and wake up a millionaire.

posted 08-16-99 01:55 PM ET            

Well, it'd almost be this easy. Have to make sure you count all the neutrons, photons, etc. that leave the pile as radiation also.

"Squaring c does NOT mean anything travels at c^2"

True. c² isn't even in units of speed -- it's area per time².

"The universe is expanding 360 degrees in 3 planes (X,Y,Z), like any explosion in a vacuum. It is expanding into nothing (into a vacuum)."

posted 08-16-99 08:30 PM ET            

"E=mc^2 can be proven easily. Weigh the uranium you put in to a nuclear plant, run the plant a certain amount of time, then weigh the waste. The mass defect (loss of mass) will be equal to E/c^2, where E is energy out."

I'd like to see you try to prove it! You'd have to measure every degree of temperature rise, every (photon?) unit of light, every unit of radiation, every unit of kinetic energy (blast wave), every unit of sound, etc.
It seems inconcievable that all these things and many more not listed would add up to exactly c^2 times m.
And many people have said many times in this very thread that C^2 is not the speed of light squared. I know I sound like I'm taking the piss but it looks like you only read half the posts and then skipped to the end to reply!