dgeake Posted July 11, 2003 Report Posted July 11, 2003 fatty_ashy "Erm, I was wondering if travelling at the speed of light actually means instant travel." alternative-3 "- If I were moving at the speed of light through deep space or whatever, would I get squished into a near-2D line? Would I survive?" 1. You cannot move at the speed of light as long as you have mass, because as you approach the speed of light, your mass increases and the energy requred to accelerate you faster increases. 2. As you approach the speed of light your mass approaches an infinite mass. This is how it appears to an observer outside your inertial frame (at rest). 3. Your dimension in the direction of travel also appears to contract by any measurements made by such an observer. For non-relativistic speeds this contraction is very small. The formula for the Lorenz contraction is: L = L'*sqrt(1-v2/c2) where L is the length measured by the observer and L' and v are the length measured by the subject, and the subjects velocity measured by the observer. You can see that L and L' are nearly equal unless v approaches a significant fraction of c (which is the speed of light.) 4. Time appears to slow down to an observer at rest relative to you also. The formula for time contraction is: t' = t*sqrt(1-v2/c2), where t' is the observers time, t and v are the subjects time and velocity relative to the observer. You can see that unless v approaches a significant fraction of c (the speed of light) there is very little difference between t' and t. 5. You notice none of these things until you return from your trip. On your return, we will disagree on how long you were gone. Our time measurements of your trip will differ by a certain amount, depending on how fast you traveled and how far. And both of us will be correct. 6. If you could travel at the speed of light, it would appear instantaneous to you in your inertial frame, because time (for you) would have stopped for the period which you were traveling at the speed of light. But to me, you would appear to have traveled at the speed of light, not instantaneously. This is the opposite of what sardonyx247 said, but (s)he was correct in stating that time is relevant only to the observer. Observers who are in the same inertial frame measure time identically. If the inertial frames differ, then their measures of time also differ. Lucky for us the difference is very small at speeds we are likely to travel at. 7. Fatty_ashey had a question regarding the distance of the trip as it appears to the travelers. This is interesting because their meter-stick would have contracted in the direction of their travel, but because of time dilation, they would also think they had traveled for a shorter time (and they actually did in their inertial frame); but at a higher velocity (their meter-stick has contracted). But when they multiply the time by their measured rate of travel the two effects would cancel out and they would measure the distance of the trip to be the same as an observer in a more or less stationary inertial frame. This is contrary to the conclusion drawn in the second link below. I think the difficulty is because the author is using v as measured by someone outside the inertial frame of the travelers when he should have used v as measured by the travelers. I was wrong once before, this might be the second time. ;-) (This note added later... There is something inconsistent in my explanation above, and I must admit, I am not sure what the answer is. As you travel at a constant velocity along the route, the route appears to be moving past you at some velocity in the opposite direction, and thus would appear contracted to you. I'm beginning to think that as you travel the route at a relativistic velocity it will actually seem to be a shorter route.) check these liniks: http://www.drphysics.com/syllabus/time/time.htmlhttp://www.physics.umass.edu/gemsFolder/p116f02/Lengthcontractionexample.pdf
dgeake Posted July 11, 2003 Report Posted July 11, 2003 Alternative-3, you would survive as long as the accelleration wasn't too great. You would not notice the Lorenz contraction at all. In a Newtonian universe if you accellerated at 1g (9.8 meters/sec/sec - very confortable) it would take 3*10^8 / 9.8 = 30612200 seconds to reach c. Thats about 1 year. And of course after a year you really wouldn't be going that fast because relativistic effects would prevent that. Guess what! Something does travel faster than the speed of light. (But it has no mass.) At least according to some scientists:http://www.cnn.com/2000/TECH/space/07/20/speed.of.light.ap/index.html
purdyboy Posted December 2, 2003 Report Posted December 2, 2003 has everyone gone fishing? why has nothing been said since july?
Tormod Posted December 2, 2003 Report Posted December 2, 2003 Hey purdyboy, welcome - I guess this thread fizzled out during the summer holidays. But as you might have seen there are lots of other threads to catch up on...it seems the 5th dimension is all the rage these days. Tormod
purdyboy Posted December 10, 2003 Report Posted December 10, 2003 Thank you for the welcome. Hopefully I'll be able to get into some heated discussions soon. I'll just wait till the next entry. Then I will unleash.....later people.
fatty_ashy Posted December 12, 2003 Author Report Posted December 12, 2003 Fishing is a good time to relax your nerves. there is that extra bonus of actually catching fish!! i like salmon. hmmmm....salmon....
shut_up Posted December 16, 2003 Report Posted December 16, 2003 Was wondering. If your at the speed of light how do you slow down?
Roberto Posted December 17, 2003 Report Posted December 17, 2003 As far as we know, in modern physics only massless particles travel at the speed of light and, while they are massless, they remain at this speed. There is the possibility that some massless particles create other particles with mass, but I think it is another effect.
GAHD Posted December 17, 2003 Report Posted December 17, 2003 Well, only light moves at the speed of light, one cannot necessarily say the light is mass-less. Photons do have some minute mass to them, much like electrons have mass but this mass is left unsaid as it's 'close enough' to nothing to not really matter (pardon the pun). A slightly better way of putting it might be that only mass-less objects (a contradiction, but the universe is full of them) can exceed the speed of light. @shut_up: <u>IF</u> time-dilation occurs proportionally to speed, once attaining the speed of light you could not slow down until you hit something to rob you of your inertia, you’d be stuck in a moment of time unable to do anything. On the plus, you wouldn’t have to worry about being frozen, you wouldn’t even notice until you slowed-down. On the minus, you would have no real idea how far you had gone, what had affected your direction, or how long you had been frozen. A problem, well more like uncertainty, is that once the speed of light is attained there is a great deal of debate as to what actually would happen to matter. Many people theorize the matter would break apart at the sub-atomic level due to excessive energy within the atomic structure, while some others theorize the matter would mealy take on similar properties to light itself, acting as both a wave and a particle. A third school of thought theorize that both will occur, the matter will disintegrate into sub-atomic quanta then spontaneously re-integrate into an equal mass of photons and other (theoretical) wave/particles. Quite the tricky area as most of our data comes from varied, often disputed sources and is largely constructed on a matchstick house of mathematical equations.
Roberto Posted December 18, 2003 Report Posted December 18, 2003 Light has no tiny mass associated to, it is really massless in every physical theory. Concerning this, I recomend the page: http://math.ucr.edu/home/baez/physics/ParticleAndNuclear/photon_mass.html by John Baez. About the theories of what happens when a body reaches the speed of light, I would like to know the sources from where you´ve got them, because as far as I know, there isn´t the possibility of accelerating till the speed of light in modern physics. Okay, I may be wrong, but first I need to see the sources.
halogenesis Posted December 22, 2003 Report Posted December 22, 2003 I agree. Anything with mass cannot reach the speed of light, but I think the ideas Gahd has posed are more like thought experiments... either way I would be interested to see the sources for these, whether it be websites or books.
GAHD Posted December 30, 2003 Report Posted December 30, 2003 @ Roberto, concerning the subject of photons having mass I recomment this paper:http://www.physical-congress.spb.ru/english/baziev/baziev.aspby D.Kh. Baziev Now while some of his extrapolations seem a little overzelus even to me, the measured weight change in the sealed experiment does seem to conclude that the exiting photons carry (anti?)mass. The other conclusions drawn from this experiment are still twisting ther way through my brain. On a slightly different topic, there is also a paper revising the oft used Hafele-Keating experimenthttp://www.physical-congress.spb.ru/english/spenser1/spencer1.asp by Domina Eberle Spencer and Uma Shama Upon revisiting the fidings of the experiment, they found some rather disturbing inconsistancies with the interpritation of the data. Unfortunatly from what I can gather the hosting site for the image files has gone down, requireing a bit more effort on my part to locate the raw data and compare figures with the data given in this writing. As to photon mass causing problems with the currenly accepted model of physics, there have been a few papers specifically on the subject where a photon can have mass. On such paper I have found available online:redshift.vif.com/JournalFiles/Pre2001/ V04NO2PDF/V04N2MU2.PDF by Hector Munera on the topic of my sources for matter accelerated to a velocity of c, I'll be back with another post for each of those schools of thaught as i can relocate the relevent information.
wavelength? Posted January 1, 2004 Report Posted January 1, 2004 I think the only way to travel at the speed of light is to convert yourself or your spaceship and its entire contents into a wave length, which travels at the speed of light. ALthough this is not possible yet, they are working on it at the area 51 complex! I have done extensive research on the HAARP project which is directly related to the montauk project. Both of these projects experiment with wave lengths and the effects it can have on humanity, the environment and space-time. I am currently reseaching sending electricity via electro-magnetic waves. (wireless electricity)!!!!
GAHD Posted January 2, 2004 Report Posted January 2, 2004 lol so you're working on a tesla coil Wavelength??
syndicated Posted January 3, 2004 Report Posted January 3, 2004 although this discussion has seemed to have veered off topic, the mention of wireless electricity reminded me of something I had thought up about a year ago.What if we were able to create a device able to convert all forms of electromagnetic radiation into electricity? I mean theoretically, if you had a large enough reciever, able to recieve energy (x-ray, gamma ray, delta rays, alpha rays, microwaves, infrared, UV, etc...) from any direction in space, and convert it to electricity, wouldn't that be the ultimate "green" energy source for Earth? I think if we're able to convert chemical, kinetic, and thermal energy into electricity, there must be a way to convert electromagnetic energy to electricity, no?
Primal Fears Posted January 4, 2004 Report Posted January 4, 2004 Wavelenghth?-- HUMM I can see your side to the story but i dont see how u can change matter in the a wave length and back in to matter... this is not imposable just improbable and this means that a person could never travel at the speed of light UNLESS science can ever create a device to change matter into a wave length and back to matter... witch at present seems to be a too large an undertaking for modern sience to complete (Primal Fears )
Tormod Posted January 4, 2004 Report Posted January 4, 2004 GAHD wrote:"Well, only light moves at the speed of light" Hm... the force of gravity, and radio waves, at least, also move at the speed of light. No photons there, massless or not. Tormod
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