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Acrylic
11-04-2002, 11:57 PM
Whenever you get irritated, take a deep breath and think "what can people really know in the field of science when you know that e=mc2?" well.....that works for me....just to take me mind off things and for a laugh!

Drunken_Sailor
11-11-2002, 04:25 AM
Originally posted by AcrylicGuitar
what can people really know in the field of science when you know that e=mc2?

As far as the implications of E=mc2, well, many many books have been written about that, and I don't see how you expect a decent answer in just a short forum message...but here's a tip from the iceberg...

First off, you phrase the question as though E=mc2 should make things more complicated and confusing. This abbreviated equation gives relations to mass and energy (except when dealing with photons, which opens the door on a whole other group of derivative equations involving wavelength and Planck's constant, as well as momentum...). It also sets the limit on what we can achieve in the realm of modern physics. I.E. the speedlimit at which we can physically travel, etc. So, your question is a bit of a joke, really. There is more to the universe than just energy and mass.

Joshi
11-11-2002, 02:30 PM
E=MC2 was devised many years before eintien found it, he was just the first to go public with it because everyone else was smart enough to know what that information could be used for (i.e, atomic bombs are created using this formula)

Drunken_Sailor
11-12-2002, 08:31 AM
HAHA!!!! Where did you come up with that? Please, please, please give me your sources and references. E=mc2 is the child of relativity, so I wonder how it was created before Einstein came up with relativity physics? The concept of an atomic bomb didn't come about until AFTER the implications of relativity became apparent. E=mc2 is basically a relation to an object's REST mass (which is why I stated that when you're dealing with photons, you use a whole different set of equations) and its energy. It's not some magic equation that holds the key to everything. But it does do a good job of explaining a few things.

And AG, in relation to your questions, are you going to respond to those? Or just make preposterous claims that I seriously doubt you have any supporting evidence for? If you do, please share it. And if you give me a link to yet another conspiracy site, I won't be surprised. Maybe it was hidden along with the missing Maxwell equations.

Who came up with that equation before Einstein?

LOL! Probably MRS. Einstein!

SuicidalXWing
11-12-2002, 11:45 AM
E=mc2 has more to do with time travel than the A Bomb. Time in relation to elevation and speed, Et cetera. I think, can't remember. Haven't gone over the whole relativity equation for a few years, so I may have forgotten or mixed up info. If I'm right, somebody back me up or correct any minor errors.

raVen_image
11-12-2002, 02:24 PM
Originally posted by Drunken_Sailor
There is more to the universe than just energy and mass.
Prove it. The equation says that mass IS merely trapped energy, so you may conclude that energy and velocity are the only things that truly exist.
Originally posted by SuicidalXWing
E=mc2 has more to do with time travel than the A Bomb.
What?

E=mc² talks about the amount of energy found in mass. As you can see, it takes very little m to make a whole lot of E. It was EXACTLY the basis for the Hiroshima bomb. It has nothing to do with time travel.

The equation is very important when we talk about nuclear reactions. For example, the sun fuses hydrogen nuclei (protons) into helium nuclei (each of which is made of 2 protons). It turns out that if we add up the masses of the protons at the start of a fusion event, the total mass is slightly greater than the mass of the the helium nucleus at the end of the process. Where does the left-over mass go? It is converted to energy in the fusion process. This is known as binding energy, for obvious reasons. The amount of binding energy released when hydrogen fuses to helium is given by E=mc², where m is the mass difference between the final and initial states. This energy appears mostly as heat, which is why the sun is so hot.
http://www2.abc.net.au/science/k2/stn-archive1/posts/topic17622.shtm
http://www2.abc.net.au/science/k2/stn/september2000/posts/topic133203.shtm

Since Einstein, himself, said that the speed of light is the absolute limit, it would be impossible to travel backward through the space-time continuum. The best you could do is stop time (relative to yourself), but you can't go backwards. When you assume that it's possible to travel faster than the speed of light, you're taking the laws of physics and punching them in the stomach and throwing them down the stairs.

The problem is that you can't say, 'Hey, what would happen if you could go faster than the speed of light?' because that's totally physically impossible. It's not possible to go faster than the speed of light, so the laws of physics can't possibly say what would happen if you imagine things that way in some hypothetical universe. Physics is a complete package: once you decide to ignore one physical law, you're ignoring them all.

You run into a similar problem when you ask 'What if I could divide by zero?' or 'What if I could build a perpetual motion machine?' or 'What if I went back in time and killed my grandfather before I was born?' There's no answer, because the question doesn't make any sense.

Of course, this doesn't bother the writers of Star Trek. They go faster than the speed of light every show and travel into the past like it's a trip to Disneyland. This brings up an interesting point, however: The idea of a space-warping engine is NOT entirely a bad one! Warping space would allow you to travel as if you were moving faster than light by changing the structure of the universe, at least temporarily. You would end up in a certain location much faster than if you travelled there the 'normal way,' kind of like a secret passage. Happily for relativity, you would STILL not actually be travelling faster than the speed of light in local space, so Einstein's 'speed limit' still holds.

The point is that though it's fun to think about and enjoy in science fiction, truly going faster than the speed of light is a violation of the laws of physics and therefore can not really be discussed by physics. I can't say time would reverse itself or not exist or anything because those aren't even options. It's like if I invited you out to dinner and you told me you absolutely couldn't come, but then I asked you whether you were going to have the soup or the salad!

Now, all of us do time travel forward ... one moment at a time. As far as going much further forward? .... there are those who are approaching the hypothesis of time travel, anyway. Take a look at how you can play with relativity, when you are talking about singularities.
http://freespace.virgin.net/steve.preston/eq.gif
Points to note:
r in the integral is the Schwartzchild radius of the black hole,
The S_i are elements of the 11x11 dimensional super-string tensor. These elements incorporate the factor of c^2.

The Hawking Hamiltonian is an extension of the Newtonian Hamiltonian H_N multiplied by the product of the rotating vector mass M_R and the angular velocity w, which of course defines the vector angular momentum of the black hole.

Joshi
11-12-2002, 02:35 PM
DS, did i say anything about e=mc2 being some kind of magical spell holding the key to everything? okay, so i may have been joking about the whole 'someone came up with it before einstein' but it is true that derived from this equation came the atomic theory, and so the atomic bomb was born some time later.

to put it in it's simplest explanation, e is energy, m is mass and c is the speed of light (probably in km/s) meaning that the speed of light squared mulitiplied by the mass of the element or compound would equal teh ammount of energy one would be able to accumulate from this substance when given the correct stimulus. to most element, this may not do anything but create maybe a small spark. the atomic and nuclear element (uranium and so one0 on the other hand would accumulate enough energy to creat and atomic blast. of course any idiot could have gotten some uranium before einstein came up with this theory, light a flam to it and created a pretty impressive explosion, but from discovery, they had known it was unstable and so didn't make it readliy available to the public like hydrogen or potassium, the less reactive elements.

this is why i said that einstein ahd the wrong idea about telling people about the theory of relativity, because this equation will decide the fate of many people in the very near future if bush and hussain has anything to do with it.

Drunken_Sailor
11-13-2002, 04:12 AM
LOL

"Albert, dear, I have a few ideas about mass and energy..but you can't tell ANY body..."

(well, I think I read something about her being a smart lady !)
:-)

Ok...first let me say that you're preaching to the choir. Interesting topic from talking about tensors and the Schwartzchild limit, to proposing that all it takes to get a nuclear reaction out of some uranium is to light it on fire. Ducks in a row, my man.

Second, you're right. E=mc2 does deal with the relation between mass and energy. When you want to talk about time, and the relativistic effects that deal with it, the equation you use is SQRT(1-(v^2/c^2)). This is known as time dilation. I could go more in depth with it, but I won't.

Originally posted by raVen_image
E=mc² talks about the amount of energy found in mass. As you can see, it takes very little m to make a whole lot of E. It was EXACTLY the basis for the Hiroshima bomb. It has nothing to do with time travel.

The original equation is quite involved, and opens the door to figuring out many other characteristics of matter. Here's the full equation: E^2=m^2c^4+p^2c^2. You can take the square root of this and it becomes E=+/-mc^2+pc. Note the +/- due to taking the square root. Now, this is an equation showing the relation between energy(E),momentum(p), and rest mass(m) of a particle. When dealing with photons (which have no rest mass) the equation reduces to E^2=p^2c^2, or p=E/c.

Now, let me take a step back real quick, since I just got into photons. Since we all take that there exists a particle/wave duality, energy is related to frequency by Einstien's equation E=hf. (I use f because this message board doesn't accept irregular characters). Where h is Planck's constant (h=6.6e-34 joule seconds) and f=frequency. Now, like I mentioned above, p=E/c, or, now that we are dealing with duality, it is easier to relate energy to momentum by using p=hf/c, which is the equation Einstein derived for light quanta. So, it acts as sort of a bridge between classical (relativistic) physics and quantum physics. So, let me recap.

When dealing with particles (excluding photons) we use E= +/- mc2+pc.

When dealing with waves, we use E=hf and p=hf/c.

When dealing with both, we use E^2=p2c2 OR p=E/c.

One more thing, and I think we should be done here. The final relation we need to talk about is where wavelength fits into all this. Wavelength (l) is related to frequency (f) by l=c/f. So, pl=h, since, if you remember, p=hf/c.

Alrighty then. That's all I've got.

By the way...if you need the definition of a singularity, just ask.

I made an error as well, need to correct the value for h:6.55e-27 erg seconds. (joule seconds)

Joshi
11-13-2002, 07:21 AM
hey, i didn't say that lighting uranium on fire would create and atomic explosion, just a pretty impressive one, and you'd have to agree with that now wouldn't you. i mean, you wouldn't expect a small spark to come out of a very unstable gas like uranium, even considering that it reacts with pure air for a start.

Drunken_Sailor
11-13-2002, 09:36 AM
I believe uranium is a metal.

SuicidalXWing
11-13-2002, 11:03 AM
Uranium is a metal. And you know what irritates me, the fact that you people won't shut up about e=mc2 already. Gah!!!!!!!!

Joshi
11-13-2002, 02:50 PM
it is a metal, i was mistaken. and i'll shut up about this now. who started this whole e=mc2 crap anyway. it was AG wasn't it?

Deadmeat_X
11-14-2002, 03:36 AM
Yep, AcrylGuitar said it first...and you all followed his off-topic remark (take a deep breath and think "what can people really know in the field of science when you know that e=mc2?" ).Some of you must be really bored, to start a discussion about a loose sentence that had no specific meaning...no offense...

Drunken_Sailor
11-14-2002, 05:40 PM
It's not really boredom...well, maybe it is. There just hasn't been a whole lot of action around here lately. So, whenever there's a topic about relativity or quantum physics, I jump all over it. My brain needs to get out and strech now and then. He just happened to bring up the right topic...

Charred-Phoenix
11-15-2002, 12:45 AM
All i relaly have to say is that e=mc2 has been disproven as light loses momentum and as such the speed of light is not a constant :P

Drunken_Sailor
11-16-2002, 09:07 AM
Hmmm....I've heard speculation on these theories before. I'd like to read more, so throw me a link. I'd love to see this...

Drunken_Sailor
11-20-2002, 02:40 PM
As far as I can remember, Einstein developed relativity BEFORE he got married.

If you could indeed just "light uranium" with your Bic, I would be truly impressed.

E=mc squared has very little to do with the atomic
bomb...Nuclear radioactivity does..

The force that holds the quarks together is very
strong. Two quarks have not been separated.
But the force they have on other nuclei weakens
with distance...

When a nucleus gets big enough protons can be far
enough from each other that the repulsive electro-
static force is greater than the strong ( or
color force as it's called by some )...It can
come apart quite readily...

Madam Curie had more to do with the development of
the bomb than Einstein or any of his equations
did...

The only thing he DID do in relation to the bomb
was to write a letter to FDR encouraging him to
proceed with the Manhattan project in view of the
horrors he was witnessing in Germany...

The significance of E=mc^2 is that it tells us that one raisin has enough power to start up and
run all of New York City for one day...

One box of raisins converted to energy can power
up the whole country and a few more will do the planet...

So, you and I might wonder what's going to happen
when all the oil dries up....A particle physicist
just shrugs and says," So what? Let it run out."

All the technology around you is slowly seeping out of date, including your body....

Just guess how much food you are going to need in the future when your body gets re-alligned and
made to convert higher percentages of food energy
for use????

Joshi
11-23-2002, 04:51 PM
well, first of all, it will take many hubndreds, if not thousands of years for the food to run out. remember our primary source of food and energy is the sun, and that wont bunr up for quite a while. also, the process of our body changing that your talking about it a form of evolution and also may not haoppen for a while. i'm not saying that if it doesn't happen to us then we shouldn't worry about it, we should, but by the time it does happen, people would have worked on it for some time and have come up with, or come close to, finding a solution.

hang on a second, weren't we not carrying on this E=mc2 thing, if you wan't to carry it on, start a new topic. lets get back to what irritates us shall we?

Feral
11-23-2002, 06:45 PM
This is now the official topic for E=MC2. Enjoy :p

Acrylic
11-23-2002, 10:16 PM
Whoa, for a second, I thought,"Dang, I didnt create this post" lol. i was scared someone hacked into my name........ o.O

Kjølen
11-27-2002, 07:20 PM
Originally posted by AcrylicGuitar
e=mc2

what you just said there is:

m • c • 2 = e. You really need some ASCI2 for the squared ² :D
Then it's be m • c • c = e. :D ;)

Feral
11-27-2002, 07:50 PM
Yeah, that was me, sorry. I couldn't be bothered to look for the squared symbol :D

murta
11-27-2002, 11:00 PM
I don't have time to read through all these long-ass posts, but I think when SuicidalXWing said about "E=mc2 has more to do with time travel than the A Bomb" that he was thinking of Einstein's (unfinished) unified field theory. There were rumours that th US military adapted Einstein's work on this theory and ended up creating some sort of time travel/teleportation device, although that's highly skeptical

Raven: What's to say that it's impossible to travel faster than light? Fair enough it would be damn near impossible to navigate, as you'd have passed through something before you saw it. I don't believe that travelling at, or beyond, the speed of light would affect your place in time, it's just based on an outside perspective of the body in question's movement through space. So, say if a ship did possibly move faster than light, therefore meaning that nobody outside of the ship could actually see it until it slowed down, but it is still simply moving between points, albeit at a vast speed. It's kind of like Scientist's trying to reach Absolute Zero, they're never going to get there, because no matter how close you get, you can always half the gap between your status and your target. In the case of Absolute Zero the molecules will always be moving, no matter how infinitely small the movements are. So I believe thatthe opposite is true, and that speed is also infintely large. Light isn't the fastest possible thingy, particles out in space affect it and what not and even if they didn't, there's still something out there that will eventually go faster than light. Light is just something that moves incredibly fast, it isn't the be all and end all of speed limits. In my crazy little mind I believe that time has a speed and that has the ultimate limit, since it will be impossible to move faster than time itself, although it would be possible to come incredibly close to breaking the time barrier, it could never actually be achieved, which is why time travel is impossible. Plus as mass/energy cannot be created/destroyed, if a body were to 'jump' through time it would royally screw the universe up. I'm tired so this is probably amazingly random and stupid

Oh and perpetual motion is kinda the same, no matter how close you come, it can never be achieved, because the nothing in the universe is perfect, so they'll always be something acting on the 'device' or the energy being converted somewhere

Joshi
11-28-2002, 01:32 PM
i believe that time travel will never be possible because quite frankly, the universe could not put it into rational explanation.

consider the ant if you will.

thousands of years ago, you an ant bites the leg of a horse. this horse gets infected with a disease and isn't able to walk (i'm not saying an ant could do this, but basically something small. the rider of the horse has to get a message to somewhere fifty miles away using his horse and if he doesn't do it in time, there will be a terrible battle. of course, he now has to find a new horse. he doesn't send the message in time and battle comenses, killing hundreds of people.

now lets say that you wen't back in time and accidentaly stepped no that ant or small creature. what would happen. well first of all, there would be no battle, and many people wouldn't die. this has already changed the course of histoyr. second of all, what if one of teh people who was meant to die, but didn't because of you, went along, and killed your ancestor. well then, you wouldn't have lived.

now the universe can't explain this. if you weren't born, you wouldn't have been able to go back in time and killed the ant, in which case history would have been right again and you would have been born, and therefore killed the ant. gettit. that's why time travel will always be impossible.

plus, if it was possible, wouldn't someone have done it in the future and come back into the past to tell us about it? no history of it so far, no history of it at all.

Kjølen
11-28-2002, 01:36 PM
Originally posted by Neil Joshi
now the universe can't explain this. if you weren't born, you wouldn't have been able to go back in time and killed the ant, in which case history would have been right again and you would have been born, and therefore killed the ant. gettit. that's why time travel will always be impossible.

Yes i've thought of that before, but that might mess up time and cause a rip in time or the time space continium what ever destroying the universe.

But I don't think time travel is possible either.

Acrylic
11-28-2002, 01:56 PM
Originally posted by murta


Raven: What's to say that it's impossible to travel faster than light? Fair enough it would be damn near impossible to navigate, as you'd have passed through something before you saw it. I don't believe that travelling at, or beyond, the speed of light would affect your place in time, it's just based on an outside perspective of the body in question's movement through space. So, say if a ship did possibly move faster than light, therefore meaning that nobody outside of the ship could actually see it until it slowed down, but it is still simply moving between points, albeit at a vast speed. It's kind of like Scientist's trying to reach Absolute Zero, they're never going to get there, because no matter how close you get, you can always half the gap between your status and your target. In the case of Absolute Zero the molecules will always be moving, no matter how infinitely small the movements are. So I believe thatthe opposite is true, and that speed is also infintely large. Light isn't the fastest possible thingy, particles out in space affect it and what not and even if they didn't, there's still something out there that will eventually go faster than light. Light is just something that moves incredibly fast, it isn't the be all and end all of speed limits. In my crazy little mind I believe that time has a speed and that has the ultimate limit, since it will be impossible to move faster than time itself, although it would be possible to come incredibly close to breaking the time barrier, it could never actually be achieved, which is why time travel is impossible. Plus as mass/energy cannot be created/destroyed, if a body were to 'jump' through time it would royally screw the universe up. I'm tired so this is probably amazingly random and stupid

Oh and perpetual motion is kinda the same, no matter how close you come, it can never be achieved, because the nothing in the universe is perfect, so they'll always be something acting on the 'device' or the energy being converted somewhere

When did Raven post in this thread???

Feral
11-28-2002, 02:04 PM
Go up to Raven's post...I think it's around there somewhere.

Drunken_Sailor
11-29-2002, 04:00 AM
The term e=mc2 means energy = mass times the speed of light squared. This is important beause the key element in nuclear physics is energy and mass, and their relativity to each other.

Originally posted by Neil Joshi
i believe that time travel will never be possible because quite frankly, the universe could not put it into rational explanation.

consider the ant if you will.

thousands of years ago, you an ant bites the leg of a horse. this horse gets infected with a disease and isn't able to walk (i'm not saying an ant could do this, but basically something small. the rider of the horse has to get a message to somewhere fifty miles away using his horse and if he doesn't do it in time, there will be a terrible battle. of course, he now has to find a new horse. he doesn't send the message in time and battle comenses, killing hundreds of people.

now lets say that you wen't back in time and accidentaly stepped no that ant or small creature. what would happen. well first of all, there would be no battle, and many people wouldn't die. this has already changed the course of histoyr. second of all, what if one of teh people who was meant to die, but didn't because of you, went along, and killed your ancestor. well then, you wouldn't have lived.

now the universe can't explain this. if you weren't born, you wouldn't have been able to go back in time and killed the ant, in which case history would have been right again and you would have been born, and therefore killed the ant. gettit. that's why time travel will always be impossible.

plus, if it was possible, wouldn't someone have done it in the future and come back into the past to tell us about it? no history of it so far, no history of it at all.

What you outline here is just another version of the famous "grandfather paradox". I guess it makes sense but it's one of those things that is hard to logically justify. There have been suggestions that it could happen, but that involves alternate realities or universes etc. which don't make much sense either.

Drunken_Sailor
11-29-2002, 09:30 AM
I liked Neil's last paragraph no matter that I've heard it before. I like that episode of STAR TREK where Kirk et. al. got caught in a time warp/rip/whatever and wound up stuck in orbit above Earth in the year 1960 (?) It was fun. Naturally the USAF scrambled a jet to investigate. Well, the Enterprise didn't much care for that and froze the jet in time and beamed the really confused pilot on board. Cool. You can imagine his amazement. Well, end of story. The pilot was "returned" to his aircraft and he didn't remember a thing. Consequently he radioed back that the "bogey"/UFO had turned out to be nothing.

Joshi
11-29-2002, 01:41 PM
Originally posted by Drunken_Sailor
What you outline here is just another version of the famous "grandfather paradox". I guess it makes sense but it's one of those things that is hard to logically justify. There have been suggestions that it could happen, but that involves alternate realities or universes etc. which don't make much sense either.

ah yes, alternate realities, the basic idea that if something could physically happen, it will, in another reality, happen. so don't think of an alternate reality as a place where maybe people could fly because all laws of physics says that we can't, be say in history, england didn't for some reason win the spanish armada, or the declaration of independance wasn't signed for some reason or another. this is possible and could have happened, but didn't. that is not so say ti couldn't though, and this is where the idea of alternate realities come from. and this would be a good reason for the grandfather paradox (anyone see futurama when fry goes back in time, kills his grandfather and sleeps with his grandmother, sick, but he's basically become his own grandfather. cool). but there is another version of this.

in a book i'm reading (actually i'm cheating, i bought it on CD, but never mind) a captain of the guard goes back in time along with a criminal he was pursueing. when all this happened, this captain (named Vimes) got his eye cut and it was nursed and then had an eyepatch put on it. now many things happened. in the past, when this man first joined the watch (or police) he was mentored by a man named john keel, who just so happened to have an eyepatch and cut eye. after this john keel avvied in his town, he was mugged by two muggers, but was able to defend himself (how he got the patch) and stay alive. but now, these two people have come back. this time, the criminal vimes brought back with him helped the two muggers and killed john keel. now without his mentoring, the young vimes will grow up to be lowsey, or dead and so now the older vimes must pretend to be keel and tutor himself. so already this is a parralell universe created by time travel.