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Quote:My question is: if an object is travling at the speed of light, how will it see the light traveling at the same direction?
Quote:Quote:My question is: if an object is travling at the speed of light, how will it see the light traveling at the same direction?It should try to arrange to travel through a dusty region which reflects toward it some light originally traveling in parallel. When it detects the reflected light, it can make inferences about the light that was not reflected, but continues on a parallel course with it. (In much the way we can see a car's headlights shooting out in front of it because of bugs and such which are caught in the headlight beams.)
Quote:You're making the false assumption that because the light source is traveling at near the speed of light, any light emanating from it is necessarily polarized in the direction of travel.
Quote:There would be nowhere for the light to travel to.
Quote:An object with non-zero rest mass is not a photon.
Quote:Again, the universe would appear to be contacted to a zero depth in the direction of motion. Where are the photons going to travel to?
Quote:Hi, we all know the speed is constant from all observers regardless of the reference speed of the observes. My question is: if an object is travling at the speed of light, how will it see the light traveling at the same direction? Or will it be able to see the light at all? Please ignore the reality factory such as it is impossible to achieve speed of light for object with any mass.
"Scientists aren't perfect, just peer reviewed.""Eye of Sauron Observatory", featuring "Sauron's Other Eye", 16" dob, conical Royce mirror.
Quote:If you were traveling at c, no matter how far away you were from something you would hit it in zero seconds. Also, your kinetic energy would be infinite so the collision would destroy the entire Universe, so this isn't something you should try at home.
Quote:Protons have rest mass. Gamma ray photons dont have rest mass. Protons can't travel at c. The LHC accelerates protons close to c but can't reach c.
Quote:So photons don't have any mass? Must not, or the universe could not exist. Gamma rays must have no mass either right?
Quote:Peter's comment points up for me how trying to imagine the implications of doing something that is mathematically and physically impossible is, well, impossible.
Quote:It's actually an interesting topic because traveling at c for anything with non zero rest mass is impossible since it would require infinite energy to get to c. However, black holes have characteristics that are equally paradoxical at the event horizon and black holes do exist. The equations of General Relativity blow up at the event horizon. You get zeros and infinities as answers. The black hole paradox is a real puzzle to physicists. I know Hawking has come out recently with some sort of solution. I don't know all the details.
Quote:Quote:So photons don't have any mass? Must not, or the universe could not exist. Gamma rays must have no mass either right?
As others stated photons have no rest mass. Photons do have energy given by e = hv
where h = Planck's constant & v = frequency.
To convert energy into equivalent mass use: m = E/c^2
Since photons are NEVER at rest and always travel at c, this could be considered
Quote:Anyway, Hawking is obviously going thru a midlife crisis and needs to rethink his place in the history books.
Quote:Quote:Anyway, Hawking is obviously going thru a midlife crisis and needs to rethink his place in the history books.
The dude is 71 years old and by all rights should have been dead decades ago. I suspect he's already gone through his existential crises and is working strictly on the theory at hand at the moment.
His place in the history books is secure, whatever happens in the future.
Quote:I'm not offended. I just very seriously doubt that Hawking's change of mind is due to anything but the ramifications of the theory combined with the data available -- data in this case also including the ramifications of other related theories.Maybe he's lost his skill for the math involved. Probably not. Maybe he's considering other factors he hadn't considered previously. Also remember that Hawking is not working in a vacuum. Even in his condition, he's not an isolated brain in a vat. There are other, very talented physicists working on the same problems, and he's almost certainly keeping up with their results and being influenced by them. That's another aspect of good science.What everyone needs to keep in mind that this is not about Hawking. It's about nature. We're trying to figure it out. Sometimes it forces us to change our point of view.