posted
I was really interested in Ender's Game after I read it and I started to look some stuff up about physics. I found this light speed theory that Einstein created and it says that if we really can get close enough to the speed of light, we can go forward in time. But, if we surpass the light speed, we can go backwards. I think that's really interesting. However, I don't know how to reach the near speed of light, but I'm sure that the people working at NASA can get closer than I can, at least for now, anyways I read about this twin theory. Look at this instance: Two twins, Bobby and Billy. They're both 19. Billy pursues his astronautical desires and goes into space on a space craft that can travel at 99.99% the speed of light. When Billy has been in space for what seems like 6 months to him, he turns back and the whole flight only took him 1 year. But when he gets back, Bobby is 70 and Billy's only 20. I think that would be cool, but, yes, sad.
"Remember, the enemy's gate is down"
Posts: 667 | Registered: Aug 2003
| IP: Logged |
posted
I think the problem with traveling at very close to the speed of light is that ones mass approaches inifinity. As ones mass approaches infinity, then the amount of energy needed to attain those speeds becomes prohibitive. So, I doubt that, unless we can find a way around these physical limitations, that we will ever come close to light speed.
Posts: 168 | Registered: Aug 2003
| IP: Logged |
posted
If not so close to the light speed as to seem at light speed, then I'm sure we can at least get 1/4 of the way there... I can't see it being too impossible, being as we are already a good fraction of the way to 1/4 light speed. But, I dunno.
"Remember, the enemy's gate is down"
Posts: 667 | Registered: Aug 2003
| IP: Logged |
posted
Why don't we all just get together, wish REALLY hard, and go outside? Then we can come back inside, possibly a long time before or after we leave.
Posts: 981 | Registered: Aug 2003
| IP: Logged |
posted
that's a good idea and I've actually contemplated on it, no matter how seriously or not, but the fact of the matter is that I'm sure we can achieve things with our minds if only we used a larger percentage of them. I know that the thing about only using about 10% of your brain has been around for (what seems to humans) a long period of time, but it's true, and if we used more of it, maybe we could do such things, and if not things exactly like these in the Ender books, then maybe we could achieve things similar to them. Maybe if we attempted to use a larger part of our brain by working really hard on certain matters, evolution would eventually -over thousands and years, mind you- do its work and we would be even more intelligent beings. With technology, we don't become more intelligent, we become smarter. We need to strive for intelligence. Anyone can achieve the goal of being smart by studying and memorizing - but what happens when something happens that you're not familiar with, or that you didn't memorize? To be intelligent, however, you can pull from the question at mind and think logistically through a problem or matter. We need to be intelligent. Think about being smart. If you memorize a song on the piano, or even memorize the notes on a staff to play that song and you don't play it for, let's say, five years. In five years, most likely, you will need some brushing up on that song, let alone play the piano very well. To be intelligent, though, you don't need to memorize it, you know it. You can't forget something that you know . It can be compared to knowing someone very well. For example, if you've had a really good friend that moved away, but you still tried to keep contact with moved really far away one day and fifteen years later, you got back together again. Chances are that nature eventually aged the both of you, unless either one of you is super-human or already amongst the walking dead (that's a joke). Imagine that - let's call your friend Emma. Okay, Emma has dyed her hair a deep red (her hair color when you had known her was blonde) and she's gained fifty pounds and she had surgery on her nose that was broken ten years ago. Imagine how different Emma looks now - you probably won't recognize her. This is because you lived for such a long period of time away from he. It's also because you didn't know her that well even before she moved away. I know, you're thinking but you said you were really good friends!! and I did in fact say just those words (or variations of them, anyway. But while you were very good friends, you still didn't know Emma. Chances are that most people - if presented with this situation - would be baffled, just like Emma's friend. This is my point. If we knew our friends better and more thoroughly, we wouldn't be baffled. We wouldn't forget. Now to state my exact point again - we need to be intelligent.
posted
I don't think we will achieve light speed for a long time. To me it sounds like light speed isn't on NASA's list right now, I think they are working on that could be achieved less than 100 years.
Posts: 9 | Registered: Jul 2003
| IP: Logged |
posted
As unohoo said, it's impossible to reach light speed, because one's mass would increase toward infinity, which would then require an almost infinite amount of energy to move the mass.
Light speed, however, cannot be achieved for another reason. It's not a speed. It's a boundary. Just like the horizon will always be there, no matter how fast you run toward it, it will always be out of reach. Yes, you can measure it, as you can measure the distance to the horizon, but you will never be able to reach it.
If you have a ship traveling close to the speed of light toward the west, and another ship traveling close to the the speed of light toward the east, when they pass, it seems to each that they are traveling at the speed of light, not twice the speed, as the math should indicate. Why is that? Obviously, because the speed of light is not stationary; it's speed moves with you, just like the horizon moves with you, regardless of any outside points of reference.
"Light is the outer limit of what is possible. It's not a physical thing, it's a boundary. Scientists agree that light has no mass. BY analogy, think of the earth's horizon. The horizon is not a physical thing. It is a concept. If you tried to put some horizon in a bucket, you couldn't do it. . . . Light is analogous to the horizon. It is a boundary that gives the illusion of being a physical thing. Like the horizon, it appears to move away from you at a constant speed no matter how fast you are moving." ('God's Debris', by Scott Adams)
Note: While I do not consider this book to be in any way scientifically factual, it has some rather interestting concepts. This one seemed to be to be true, so I say it. If it's proven otherwise, I will gladly remove it. But if it feels true, I will believe it, and repeat it, to you.
Posts: 66 | Registered: Feb 2003
| IP: Logged |
posted
Morgaine, that book of yours deserves to be thrown off the top of a ten story building. I would personally love to be there to witness its death. The speed of light is referred to as a boundary because, for so many years, man has tried to overcome it. But by overcoming the boundary , as you wish to call it, you only have to reach a speed that is 1 mile over the speed of light. The speed of light is a speed, Morgaine. The speed of light is 299,792,458 metres per second in a vacuum. Considering that space is a vacuum, the exact speed of light in space is the above llisted speed. The speed of light is the speed of light. It's nothing other than that. Not a boundary, only the rate at which light travels. One light-year is not a matter of time, but a distance. A light-year tells us how far light could travel in one year. Man can achieve any speed with time. It takes experimentation, and this is what scientists do - experiment. NASA has already found electrons and radiation belts that travel at close enough to light speed that they find worth experimenting with. Time travel is not that far away.
posted
I also wonder, Morgaine and unohoo, how you can possibly think that traveling at near light speed will infinitely increase one's mass. Electrons weigh no more than .00054 amu, the unit used to measure electron weight. Have you ever wondered why we don't see - in middair - trillions of little atoms floating around? That is because they are too small and they have too little weight to noticably feel. That is also why, even when you hold your hands palms-up in the air, you feel no weight on them (except for gravity's downward pull). On top of your hands are trillions of atoms and you don't feel it. My point in explaining to you the weight of atoms is that electrons (which are in atoms) can travel at nearly the speed of light. So I wonder this - why do you say that your mass increases to an infinite mass as you travel closer to the speed of light? It is simply false. Ofcourse one's weight will change somewhat, just as if you were to set foot in another planet's atmosphere, your weight will fluctuate. But mass is constant. Weight changes - mass is constant. We use these terms interchangably because on earth's atmosphere, mass weighs virtually the same as weight. But they are two different terms. If you were to go to another planet, your mass would stay constant, but your weight would change. Your weight, however, would not change to an infinite weight, it may double or triple, or even be halved, but your mass or your weight, either one, will not become infinite if you travel closer to the speed of light. I wonder if you think that infinite can mean two different things for two beings who weigh different amounts? Infinite is infinite is infinite. Infinite is always the same - it can't be measured b/c it continues on and on. Infinite is a word that can be used to describe the end of the universe - this is because it doesn't end. Or if it does, man cannot (or has not) measured it. So we call the universe infinite. If you're traveling in a car at 30 mph, you will weigh the same as if you were traveling at 80 mph. Your weight will not become infinite as you approach light speed.
posted
wieczorek, they think these things because they are true. The term "relativistic mass" is out-dated, but it's still basically true; the closer you go to the speed of light, from inertial observers' point of view, the more mass you gain. Nowadays, many say that the mass is constant, but it's the "total relativistic energy" that increases, as does the relativistic momentum.
You can't pass the speed of light like you can the speed of sound. Sound is a speed of the wave in a medium; a pressure wave, vibrating the particles of air. You bypass the speed of sound by making the air through which you travel go behind you faster than sound from behind you could catch up.
Light has no medium. There is no ether that vibrates as the light passes through. If I stand on the earth, I measure 3*10^8 m/s (c) as the speed of light. If I go out on a spaceship at 1.5*10^8 m/s (.5c), and measure the speed of light again, it's still 3*10^8 m/s (c). In order for this to be true, a large number of things happen. For example, in order for the earth's (rest) frame to agree with my spaceship's .5c frame the distance light passes, time has to be defined to run slower for the moving frame. Distances appear to be contracted from the moving frame's point of view to compensate. And, from the rest frame's point of view, kinetic energy and momentum increase faster than they would at slow speeds.
In fact, momentum now inceases by gamma*m*v, where gamma is 1/sqrt(1-v^2/c^2). This gamma expression is equal to 1 at rest (v=0), and blows up to infinity as you approach v=c. Your total relativistic kinetic energy is E=gamma*m*c^2, which also blows up to inifinity as you approach v=c. Given an object's mass and any finite amount of energy to be dumped into it, you can find the corresponding speed. All of these speeds will be below c.
Does this mean that it's impossible to travel faster than light? It's certainly impossible to do it just by accelerating. There are loopholes that can theoretically be exploted, but most of them seem to require rather exotic forms of matter to actually utilize. Here's hoping though.
Posts: 49 | Registered: Sep 2000
| IP: Logged |
posted
Tresof, you must not have read my posts through and through. I agree that weight increases, but I disagree that mass becomes infinite. Also, what do you think would happen if you reached the speed of light? Disappear? Explode? What?
"Remember, the enemy's gate is down"
Posts: 667 | Registered: Aug 2003
| IP: Logged |
posted
wieczorek, have you even read the book? Or are you saying that simply because you don't like the idea?
The Speed of Light can never be reached. I don't know where you read your information. Try reading Relativity Simply Explained. It should answer your questions.
Like I said, you can measure it, you can use it to calculate anything, but you can never reach it. E=mc^2. Energy is directly proportional to mass. As the speed increases, your mass and therefore the energy increases. Youd have infinite mass at the speed of light, which would need infinite energy. Trust me, I've studied Relativity at length. More than just one book. I"ve also read Time Travel In Einstein's Universe, essential for discussions like this.
Also, the Speed of Light has nothing to do with Time Travel. You would only be able to go "foreward in time", if anything. But it's not real time travel, it's simply slowing down time for you, or speeding it up for the rest of the universe.
Not true. The difference between 30 and 80 mph is minute, so we don't realise it, but there is an increase in mass and energy needed to propel it.
As c approaches the speed of light, the energy is increased to enormous proportions. Put it another way, E/M=c^2. The speed of light squared equals Energy over Mass. The fraction would have to increase proportionally with the speed you're travelling. The energy is impossible to maintain at the Speed of Light.
People aren't ignoring what you wrote, just that you have false information. Perhaps try the books I mentioned, as well as others (there are many books available at the library, in the early 500's, between 520 and 530, or under general science between 500 and 520).
Posts: 66 | Registered: Feb 2003
| IP: Logged |
posted
wieczorek, it is possible I'm misinterpreting you. But I didn't say anything about weight. In fact, in my spaceship there is no weight; weight is the force of gravity acting on a body, and I'm going to go ahead and declare the spaceship non-accelerating and free of all gravitational fields when I talk about it's velocity and how it appears to itself and the earth.
I said that your relativistic total energy increases. Your rest mass (m) stays the same; I don't dispute that, but it's your total energy that matters. The faster you go, the more you gravitate and the more inertia you have. To all outside observers, you appear to have more effective mass. Photons have no rest mass, but they do carry energy, they have finite momentum, and they gravitate; impossible unless the calculation of these properties at c involved an infinity*zero limit.
In vacuum, you simply can't accelerate to c. It would take an infinite amount of energy to get yourself to that speed. I think that if you tried for some finite period of time at constant thrust you could get yourself going to some high percentage of c (.9, .99, .999, etc) with respect to a rest observer, but, at that constant thrust, you would find that to pass from .9c to .999c would take longer than it took to pass from .4c to .7c. Eventually (again, to the rest observer), you would be getting incredibly close to c, but never quite reaching it. You would also look to be squished by Lorentz contraction, and eventually have a large enough gravitational wake to wreck planets you pass near.
And to you, yourself, on the ship, the speed of light will always be tantalizingly 3*10^8 m/s faster than you. The speed of light in a vacuum is constant, no matter how you measure it. In fact, other than the truly epic redshift you could see out the back window, you wouldn't be sure you were moving at all.
Now, in, say, water, where light travels more slowly than in vacuum, you can in fact exceed the effective speed of light. When a particle does so, there is an emission of Cherenkov radiation, but otherwise I am aware of no interesting effects.
Posts: 49 | Registered: Sep 2000
| IP: Logged |
posted
Max Factor> Although you are mostly correct, I believe there is some kind of attempt going on to create an Alcubierre space-warp drive, not that anyone expects to achieve it soon if ever.
Posts: 1041 | Registered: Feb 2002
| IP: Logged |
quote: COLUMBIA, Mo. — For the first time, scientists have measured the speed of gravity, one of the fundamental constants of Albert Einstein’s 1916 general theory of relativity. Led by Sergei Kopeikin, a physicist at the University of Missouri-Columbia, a team of scientists took advantage of a rare cosmic alignment on Sept. 8 to test Einstein’s assumption that gravity moves at the speed of light.
“Newton thought that gravity’s force was instantaneous,” Kopeikin said. “Einstein assumed that it moved at the speed of light, but until now, no one had measured it.”
Kopeikin worked with Ed Fomalont, a radio astronomer with the National Science Foundation’s National Radio Astronomy Observatory (NRAO) in Charlottesville, Va. On Sept. 8, the scientists measured the shift of a quasar, a celestial object that resembles a star. Jupiter’s gravitational force caused the quasar to shift as Jupiter passed by it closely.
“We have determined that gravity’s propagation speed is equal to the speed of light within an accuracy of 20 percent,” Fomalont said.
The scientists presented their findings to the American Astronomical Society's meeting in Seattle, Wash. The landmark measurement is important to physicists working on field theories that attempt to combine particle physics with Einstein's general theory of relativity and electromagnetic theory.
To conduct the experiment, the scientists used the National Science Foundation's Very Long Baseline Array (VLBA), a continent-wide, radio-telescope system, and a 100-meter radio telescope in Effelsberg, Germany, to make an extremely precise observation when Jupiter passed in front of the quasar. The observation recorded a slight “bending” of the radio waves coming from the quasar because of the gravitational effect of Jupiter. The bending resulted in a small change in the quasar’s apparent position in the sky in addition to the deflection of light calculated by Einstein in 1915.
“Because Jupiter is moving around the sun, the precise amount of the bending depends slightly on the speed at which gravity propagates from Jupiter,” Kopeikin said. “Since the effect is very small, Einstein neglected it in his calculations.”
In 1999, Kopeikin extended Einstein’s theory for light propagation to include the gravitational effects of a moving body on light and radio waves. Prior to this study, no one had tried to measure the speed of gravity because most physicists had assumed that the only way to do so was to detect gravitational waves, Kopeikin said. The MU scientist realized that if Jupiter moved closely in front of a star or radio source, he could test his theory.
The VBLA system is a result of a general radio technique known as Very Long Baseline Interferometry (VLBI).
“I believe this experiment sheds new light on fundamentals of general relativity and represents the first of many more studies and observations of gravitation available presently with existing VLBI technique,” Kopeikin said. “We have a lot more to learn about this intriguing cosmic force and its relationship to the other forces in nature.”
If this theory of Einstein's was not absolutely correct, how do you know that we cannot, in fact approach the speed of light? Perhaps you misinterpret what I mean and I am not explaining well enough. For this I apologize. You repeatedly say that you cannot surpass light's speed. I did not say you could. If you were to surpass light speed, you would instead enter the past. I ask that you go to nasa.gov and search for information on light speed and its effects. I also know that it is possible to get very close to light speed - NASA recently had a documentary on TLC on light speed theory and the twin paradox. Researchers at NASA have verified their feelings on this topic and believe that we can get very close to light speed, and even surpass it. I am sure that NASA's staff and workers know enough about the things they speak of to be believed.
posted
Am I the only one who can't follow the technical terms of this thread? And is it stupid to suggest that it's possible to "hitch a ride" on a beam of light, like it's suggested in the books K-PAX and On a Beam of Light by Gene Brewer (the first was made into a movie, I doubt the sequel ever will be)
Posts: 981 | Registered: Aug 2003
| IP: Logged |
posted
I'm not sure if it's possible to actually sit on a beam of light, if that's what you mean, Julie. But I'm sure that there are other ways, such as black and worm holes. There are many ways to trick theories, if what I believe (along with many people at NASA) is incorrect I think if you tried to "hitch a ride" on a light beam, you might fall through, as a cloud is really made of moisture...
"Remember, the enemy's gate is down"
Posts: 667 | Registered: Aug 2003
| IP: Logged |
posted
Maccabeus, your idea is correct. NASA is working on an experiment with time travel to attempt to find a way to disprove Einstein's light speed theory. They already proved his assumption of gravity's speed incorrect. I think it is very possible for NASA to be able to prove this one incorrect.
"Remember, the enemy's gate is down"
Posts: 667 | Registered: Aug 2003
| IP: Logged |
posted
wieczorek, I've spent a lot of time talking to a friend of mine who works at Nasa about this. You cannot reach the speed of light. You can try to get close, but you will never be able to reach 186,300 miles per second.
Well, if you want to read a new study that's just been brought to light, a scientist in England recently published a book proving that the speed of light is not a constant. He calles it the VSL theory - the Varying Speed of Light. I've read half of it, he seems to claim that the speed of light was not moving at the same speed we know it to be, at the time of the Big Bang. It was in fact moving much much faster.
If his theory is shown to be correct, then Einstein was wrong, that LS is a constant. Then who knows what can happen. But we still will never be able to reach the speed of light. The only way in an Einsteinian universe is through black holes, white holes and wormholes. If Einstein is wrong, and it's a variable, then how can we reach something that continuously changes?
Posts: 66 | Registered: Feb 2003
| IP: Logged |
quote:then how can we reach something that continuously changes?
Everything you said wass true except that. After all, the position of your keyboard keeps changing (duw to roatation of the Earth alone) and yet you somehow managed to reach it.
quote:Originally posted by Hobbes Everything you said wass true except that. [Big Grin] After all, the position of your keyboard keeps changing (duw to roatation of the Earth alone) and yet you somehow managed to reach it.
Obviously, because we're moving the same speed as our keyboard. With the Speed of Light, we're trying to match our speed to that of light, which would be impossible if it keeps varying.
Posts: 66 | Registered: Feb 2003
| IP: Logged |
posted
But like I said, we're changing speed at the same time as the keyboard. Until we're able to ride a beam of light, we will never be able to catch up to it.
Posts: 66 | Registered: Feb 2003
| IP: Logged |
posted
Wow, this is going to start getting ugly soon. Remember that this discussion started because of a BOOK. Isn't it time to stop worrying about who's right and stop arguing? Just a thought. Posts: 981 | Registered: Aug 2003
| IP: Logged |
posted
Julie, I"m not professing to be right. In a case such as this, there is no right or wrong, merely opinions. The math seems to indicate that time travel is impossible, but yet it still remains a fascinating idea, as evidenced by the thousands of SciFi and Science books dedicated to the subject. It's not a serious debate, it's just specualtions.
Posts: 66 | Registered: Feb 2003
| IP: Logged |
quote: Maccabeus, your idea is correct. NASA is working on an experiment with time travel to attempt to find a way to disprove Einstein's light speed theory. They already proved his assumption of gravity's speed incorrect. I think it is very possible for NASA to be able to prove this one incorrect.
I think you misunderstood the article you quoted. No-one has proved Einstein's 'assumptions' about the speed of gravity incorrect. Relativity predicts that gravitational effects travel at the speed of light. The experiment that was entirely consistent with this.
The part of the article talking about Einstein neglecting the speed of gravity effect in a calculation is talking about him ignoring an effect that was far smaller than the one he was interested in - much as if he'd been calculating the trajectory of a tennis ball and neglected to include the Coriolis force due to the Earth's rotation, or relativistic effects. The effects are there, but on the level of throwing tennis balls arounds, they are not important in the slightest.
Einstein's theory wasn't changed at all - a more precise calculation was done using the theory because more accurate observations could be made to test the theory to higher precision.
Oh, and just for the record - the light-speed limit isn't anything to do with light, it's essentially due to the geometry of space-time. In special relativity, particles travelling faster than light simply don't exist for much the same reasons that triangle with 17 sides don't - simple geometry. In General Rel. it's a bit more complicated of course.
Posts: 9 | Registered: Aug 2003
| IP: Logged |
posted
Umm...there is a right and a wrong here. We just don't know which is which, yet. The existence or non-existence of the possibility of time travel is not a matter of opinion. It is a matter of fact. But it's an answer we just don't have. Yet.
posted
I'm willing to admit that I may be incorrect, but my uncle works with the hubble space craft at NASA and he has a totally different opinion than your friend, Morgaine, at NASA You didn't read my last post - in it I said that I never posted anything that spoke about surpassing light speed, only approacing it. If we were to surpass light speed, we would instead enter the past. You are trying to tell me something is false that I already don't know is true.
Morgaine :
quote: then how can we reach something that continuously changes?
I ask that you forgive me if I'm incorrect, but what you said is self-contradictory. You ask how we can reach something that continuously changes. Let this be an example : the "current" light speed, as we know it, is 186,300 miles per second. (Let me note that you refer to the speed of light as a constant, anyhow). NASA develops a space craft that can travel at 170,000 miles per second. On a given day, light speed fluctuates to 167,000 mps, so this means that our space craft can surpass light speed. Tell me, is this true, Morgaine? Or if the light speed suddenly fluctuates to a speed lower than that of out ship, would our spacecraft dissolve into thin air? I'm not being vindictive, I only want to know what you think. It seems as though this innocent topic which I originally posted has turned into a thread for the need to take out anger - I see no need for that, being as you said yourself, Morgaine, there is no right or wrong, merely opinions, this isn't a serious debate, it's just speculations.
"Remember, the enemy's gate is down"
Posts: 667 | Registered: Aug 2003
| IP: Logged |
posted
I finished my undergraduate physics degree last year, and we did quite a bit of advanced quantum mechanics.
My understanding of current physics teaching and experimentation is that while people are certainly getting things *faster* - like accelerating electrons - and thus observing relativistic effects, it is physically impossible to reach proper near light speed, or indeed light speed itself. It's like light speed is an asymptote on a graph - no matter how close you get you will never reach it, and you can always get closer.
I understand that in terms of faster than light communication (and perhaps, maybe travel...?) no-one is looking at physically surpassing light speed, or even trying to get close - rather people are looking at quantum interactions between particles: there is a whole lot of experimental evidence from the 1950s on that some information (such as quantum spin) is transferred between particles istantaneously on observation. (I realise this is a bad explanation - it makes sense in my mind, but that's probably no help. It's been a year! )
Posts: 4393 | Registered: Aug 2003
| IP: Logged |
posted
imogen, I don't find that explanation to be bad at all. However, I must say (again ) that I only speak of getting close to light speed. Even 50% of the way there. You say we can never reach it, and I cannot be sure - I can hardly say that I have a degree in this topic. I do know, however, that we can develop starships that will get closer to the speed of light than we are now. Not necessarily close to light speed, but closer. And then, who knows exactly where close is, in terms of extremely large numbers??? So, this debate could go on forever and ever and we may never reach a consensus, in fact, I'm sure we won't. Just like my math teacher was saying about toilet paper rolls and roastbeef...it's a long story...
"Remember, the enemy's gate is down"
Posts: 667 | Registered: Aug 2003
| IP: Logged |
posted
weizorek, you should read a book called E=Mc^2, a biography of the world's most famous equation. It'll have a lot of the answers you seek...
Posts: 4816 | Registered: Apr 2003
| IP: Logged |
posted
And Relativity, Simply Explained. It's a good one. When you finished that, then try Time Travel in Einstein's Universe.Posts: 66 | Registered: Feb 2003
| IP: Logged |
posted
Forget all this talk about NASA and spaceships and stuff. The day to day reality of relativity is found in accelerators and cosmic ray experiments, where we are dealing with particles travelling extremely close to the speed of light (but never above it). Consider that a proton travelling at 99.9% of the speed of light has a certain energy (21.0 GeV, but you do't need to worry about what a GeV is really - its just a unit for measuring energy for particle physics). We routinely detect protons with energies over a hundred million times higher (more than 1,000,000,000 GeV). That's more or less the difference in energy between a car travelling at one mile per hour and the same car travelling at around 30,000 miles per hour. Yet these fantastically energetic protons still travel slower than the speed of light.
Special relativity isn't some abstract thing, with an arbitary speed limit that hasn't really been tested. It is tested to the extreme with very high precision in many experiments every day. The predictions for gaining mass as you approach the speed of light, and of requiring more and more energy to produc even tiny changes in speed once you get close to light speed, are born out exactly in many ways, every day.
In practical terms for space travel, we are a long way off from having the capacity to go to even a tiny fraction of light speed. In terms of powered craft, we are still stuck to around 0.003% of light speed. That's not fast.
Posts: 9 | Registered: Aug 2003
| IP: Logged |
posted
Julie, it's really rather dull, but if you wish to hear it, you can read this:
My math teacher was trying to explain this old concept that we learned back in elementary school. You've heard of PEMDAS, right? The acronym for parentheses, exponent, multiplication, division, addition, subtraction. Well, she gave us this problem for review. You can call it review, but it was still really long and tedious. So when we were done, she made us give our answers and there were about 4 or 5 different answers that we had (it gets worse - there's only 10 people in my class). So we (like kindergarteners) went over the concept of excusing someone's aunt sally (you'll know what I mean if you know PEMDAS' acronym). Then she said that if we through out the rules of PEMDAS, we could get two different answers and argue over which was right all day. Then she said, holding up a toilet paper roll, "Just like if I said this roll was roast beef. I don't think that I'd like to eat what was really toilet paper and I don't think all of you'd like to wipe with roast beef." I don't think she realized what she said was so funny at the time, but it was really funny. You'd probably think it was even funnier if you had been there. Like the "4 out of 3 people have trouble with fractions" sign. (That one's self-explanatory... hehehe)
unohoo, you're always so optimistic...
Read more books? More books? *Steams from top of head* This reminds me of my literature teacher!! Oops, I guess my true self couldn't be contained... That's a joke, you know... ------>-----^
Vulture, .003% light speed might not be fast in terms of light speed, but it's not slow ...
anonymous, that's funny.
rats - I had to delete some smilies. I didn't know there was a limit...
"Remember, the enemy's gate is down"
Posts: 667 | Registered: Aug 2003
| IP: Logged |
Printer-friendly view of this topic
![[Big Grin]](biggrin.gif)
I read about this twin theory. Look at this instance: Two twins, Bobby and Billy. They're both 19. Billy pursues his astronautical desires and goes into space on a space craft that can travel at 99.99% the speed of light. When Billy has been in space for what seems like 6 months to him, he turns back and the whole flight only took him 1 year. But when he gets back, Bobby is 70 and Billy's only 20. I think that would be cool, but, yes, sad.
![[Confused]](confused.gif)
![[Smile]](smile.gif)
![[Wink]](wink.gif)
![[Roll Eyes]](rolleyes.gif)
Isn't it time to stop worrying about who's right and stop arguing? ![[Kiss]](graemlins/kiss.gif)
Just a thought. ![[Razz]](tongue.gif)
) that I only speak of getting close to light speed. Even 50% of the way there. You say we can never reach it, and I cannot be sure - I can hardly say that I have a degree in this topic. I do know, however, that we can develop starships that will get closer to the speed of light than we are now. Not necessarily close to light speed, but closer. And then, who knows exactly where close is, in terms of extremely large numbers??? So, this debate could go on forever and ever and we may never reach a consensus, in fact, I'm sure we won't. Just like my math teacher was saying about toilet paper rolls and roastbeef...it's a long story... ![[Mad]](mad.gif)
*Steams from top of head* This reminds me of my literature teacher!! Oops, I guess my true self couldn't be contained... ![[Blushing]](graemlins/blushing.gif)
![[ROFL]](graemlins/rofl.gif)
