January 3, 200421 yr Killer asked me yesterday on server: "If a lit lightbulb would travel at speed of light (c), would we see the lightbulb lit or not?" Well, to tell you the truth, i have no idea, what would we see. There are many things to be taken into consideration. Some might think that we might see the lightbuld from the direction it is heading, and not from 'the back'. Well, the velocity addition, when considering high velocities is a little different from low-velocity physics of Newton. Newton physics tells, that matter can go as fast as it wants, as long as the force is doing its' work. In Einstein physics, no matter how fast you go, the light around you still travels at c. That is becouse no matter how big velocities you add, you still get <=c. If you add c+c, you will still get as a result c. Conclusion is this: I think we should be able to see some image of lightbulb, that means we would see the light coming from it, from every direction. But what exactly would we see, i have no idea. Thats becouse nothing with static mass =>0 can achieve the speed of light (doing that would increase their mass to infinity, shrink them to a point and would require infinite energy). Now physics knows of things, that, even taken relatively, can go faster than c. It all boils down to the definition of velocity. Everything that changes, can have a velocity (or more commonly momentum) added as a status to it. Coming down to kinematic things, we shall take a closer look at waves. Now, i have a problem you know. The following might be more difficult to understand. Well, lets try. Lets say we have waves, made of two interpolated waves (it will be more readable this way). This wave of ours has two velocities, that can define its' movement through space. One is a group velocity (if we had one wave, it would be just wave velocity. n this case the group velocity becomes wave velocity), which is velocity of propagation of peaks. The second is a phase velocity, which is the velocity of propagation of the constant phase of the wave (here is the reason i used interpolated waves, with single wave, it could be difficult to differ group and phase velocity). Group and phase velocity are not the same thing, which i will show further (which will also help me explain the main topic). Lets now say, that our wave is a relative sea wave, which hits the shore. Now lets say, that we have this bizzare situation, when wave hits the shore like this: SHORE | | | | | | ^^^^^^^^^^ WAVE We take as a point of reference a point on the shore. Lets see what is happening. The phase of wave is moving along the shore, so the phase velocity is the same as group velocity. The head of the wave travels in relation to the shore with the same speed the whole wave is. Now lets shift our wave, so it hits the shore at an angle: SHORE |///////// |//////// |/////// |////// |///// |//// WAVE In this situation we connot tell the phase velocity is the same as group velocity. The head of the wave hits the shore, and the velocity of propagation of contact between head and shore (phase velocity) si different from the group velocity (which is always the same and is directed at the way the wave is propagating). Now if the wave hits the shore head-on: SHORE || || || || || || WAVE all the points on the head of the wave hit the shore at exactly the same time, the phase travels along the shore at an infinite speed, thus the phase velocity is in fact infinite. So, even if our wave travels slower than c, becouse we said the wave was relative (and the actually what we measure as the speed of propagation is the group velocity), the phase velocity is infinite. This effect is visible also in electronics, in 'long lines'. Whew........... i told You, Killer, there would be much of typing. I just hope its understandable, more or less.
January 3, 200421 yr Author No beer for you, until you comprehend it all and much more (lets say quantum relativity). I guess its time for you to become abstinent then, eh?Really, its not that complicated. Maybe that is why most of our students drink lot of beer.
January 3, 200421 yr Author My professors would make it better of course. But they work also abroad and know all the words needed.I hope i used correct words.
January 3, 200421 yr You know... if a lightbulb moved at the speed of light... wouldn't it, like, disintegrate anyway? Wouldn't it break at about Mach 3 anyway, let alone the speed of light itself? And if it was moving in such a way, how's it being powered? Doesn't a lightbulb have to be plugged into something? And if it is by cords or something.. I would think there'd be enough there to see at least a brief flash of movement or something.I dunno. This is coming from a pure-bred loser, and a 15 year old who's never even heard of quantum relativity or any of the other stuff.
January 3, 200421 yr I hope i used correct words. I know I used the correct words. "Beer" is a correct word, ain't it? if a lightbulb moved at the speed of light... wouldn't it, like, disintegrate anyway? I wouldn't worry about that. After all you're talking to duct tape
January 3, 200421 yr lets pretend the lightbulb is a flash light and its in space so it shouldnt disinigrate
January 3, 200421 yr Author Dynamo, we were talkin not only theoreticly but also more-than theoreticly. I said that nothing can move at speed of light, unless its' stationary mass is =>0, right? What we are doing in fact is making it go at ~c[/]. Problems like powering the lightbulb are as easily ignored as the fact, that in kinematics we are using moving points instead of objects with sizes (mathematicly speaking we use Dirac's Delta instead of a function to describe their position in space). Also, disintegrate is not the right word i think. Collapse is more like it.
January 3, 200421 yr Also, disintegrate is not the right word i think. Collapse is more like it. Yes, and you collapse after having too much beer.
January 3, 200421 yr hmm....this is indeed a complex situation. We should all meet up at the next science convention and discuss the theory of Anti-Matter...how can it exist? If it exists, than it must be matter cause everything is matter, but it's the opposite of matter so would it cancel itself out?
January 4, 200421 yr In space there is not friction, only when you come to close to stars, like crossing our sun, who emit radiations who make the same effects on a comet or shooting stars = the lighting tail !Light speed is most different than velocity speed !If we havent this atmosphere and the magnetic field of the Earth, we are killed by sun light speed particules !But we have 2 holes in this magnetic fields : 1 on North & 1 on South of the Earth who let some particules to enter on the atmosphere and create the northern & southern ligths in Spring (les aurores boréales du Printemps) !Egidio.
January 4, 200421 yr Author -UnwantedHero]hmm....this is indeed a complex situation. We should all meet up at the next science convention and discuss the theory of Anti-Matter...how can it exist? If it exists, than it must be matter cause everything is matter, but it's the opposite of matter so would it cancel itself out? Anti matter exists. The definition is kinda tricky though. THats becouse anti-matter needs to have correlated matter. Here it is: Matter-Antimatter: Electrones-Pozytones Protons-Antiprotons Neutrons-None Neutrinos-Antineutrinos (electronite (?), taon, mion) Quark-Antiquark (Up, DOwn, Bottom, Top, Strange, Charm, few more which i cant remeber at this hour [2am]) Many more... and last but not least Photon-Photon (photons are anti-matter for each other or so i heard such opinion). Antimatter has positive mass, but differes by having opposite charge. You get antimatter mostly in nucleus effects: when nucleus breaks into 2 it produces neutrinos and antineutrinos (apart from other things of course). I dont remember exactly, but from what i do remember is that 0.989MeV of energy is needed to create a pair electron-pozyton though what are the other conditions i dont remember. -Born to Die]In space there is not friction, only when you come to close to stars, like crossing our sun, who emit radiations who make the same effects on a comet or shooting stars = the lighting tail ! Light speed is most different than velocity speed ! If we havent this atmosphere and the magnetic field of the Earth, we are killed by sun light speed particules ! But we have 2 holes in this magnetic fields : 1 on North & 1 on South of the Earth who let some particules to enter on the atmosphere and create the northern & southern ligths in Spring (les aurores boréales du Printemps) ! I have had most difficult time understanding what You have written. From what i gather: - In space there is a friction. Constantly, becouse space is not that thoroughly empty. Only in pure vacuum you get no friction. - If we had no magnetosphere or it would be weaker, we would be taken out by both high-energy particles and radiation. - Ionized particles coming from the sun, when affected by magnetoshpere, are driven in the direction of the magnetic poles. The friction of them entering atmosphere and coliding with it creates the coloristic effects of aurora. - Oh yeah. Although many have tried they havent yet discovered magnetic monopole. The basic magnetic structure is dipole. - But what You meant bu 'light speed being most different' I HAVE NO IDEA!!!...
January 6, 200421 yr my head hurts, thanks what r u studying / doing DITTO.... im not a stupid person by ny means...but wow....hmm..to much time...
January 7, 200421 yr I'm not a physics expert but a guess from what I know... I read your post and failed to see the relevance between the question posed and your explanation using interpolated waves. Yes the speed of light can be exceeded, but what you fail to mention is that no data can be transmitted, here is an article that might help. http://www.space.com/scienceastronomy/generalscience/faster_than_c_000719.html And to help understand why you can't go faster than light here is something from another forum (not an fa forum). "Light speed is the speed of energy itself. By trying to even close the gap between you and speed c is the equivalent of trying to close the difference of potential between the poles of your car battery. It's self- defeating, slowing you down. If you exceeded light in the hypothetical sense, you would not see your reflection in a mirror and all the neurons in your brain would not be able to leap their gaps. Catching up to light speed is not analogous to catching up to another car with your car in traffic. The difference of energy potential between each car and speed c must be the same in order for one car to catch the other at all." What would it look like? Well objects going near the speed of light from an observer's frame of reference would appear to contract. It would shorten and start to round which you mentioned. Since the light bulb couldn't go the speed of light you could look at it going near the speed of light, in which case the light would go faster than the bulb. However the bulb would be constantly sending out light. So you'd have this contracted beam of light going ahead of a light bulb that would look like a normal light bulb contracted. Despite the speed difference there would always be light in the bulb because it is constatnly going out. Persnonally I've always wondered what reflection of a reflection looks like. Get a two way mirror and a mirror face each other perfectly aligned, what would nothingness look like...
January 7, 200421 yr Author Relevence between the parts of my first post is small. First part was meant to explain the lightbulb effect. Second was mean to show, that speed of light can be exceeded, although not in the way most people think.I prefer to see the speed of light as mass-energy and time-and-space relations. But so far i have had not very much of that. Some basic Theory of Relativity on Physics' Basics and on Electrodynamics, but thats about it. Next semester we are having Quantum Relativity so i am hoping to catch up.
January 7, 200421 yr eventhough i had physiks as a major course in school i didnt understand a thing, but i know i really like beautiful women!!!!!!lol
January 7, 200421 yr LMAO!!I agree with Catdady, id rather study women than physics.And Catdady, how bout changing your name to C Diddy, if its good enough for Puff Daddy its good enough for you
January 7, 200421 yr Author -Gen.Wellsy]Kywalker....you know way too much :? Hah! This is nothing, compared to things my student friends know. Some of them are real masterminds. I am simply a mediocre, if not bottom-of-the-shelf student here. As for studying Women instead. We have some were pretty Women in our Institute. So i can do both.
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