Light speed Definition and 322 Threads

Okay, basic question regarding time and photons and I have a little thought experiment to illustrate my confusion. From what I understand, light waves do not experience the passage of time since they are traveling at light speeds, but suppose you are a hyopthetical conscious observer from...

Im just an amateur, and I read that Newton's Equation F=ma doesn't work when approaching light speeds because of a relative increase in mass at higher velocicites. What is the reason for this, if any, and is there a ratio between veolcity and relative mass I could use to make my calculations...

Seriosly, waves have different frequencies, and light is somewhere in the middle of the EM spectrum, then maybe the right or left side could travel faster than c

Hi, Is it possible for a man made object to remain in a circular solar orbit at speeds approaching light speed without a coriolis force destroying the object or disrupting the orbit. If so, what distance from the sun would be required and what would the orbital period be?KodeK reel8.co.uk

Ignoring the mass problem, imagine 2 spacecraft s are traveling at exactly the speed of light. One spacecraft directly behind the other, with only a hundred feet or so between them. If the speed of light is always the same for any observer, is it safe to say that when the trailing...

I understand that the speed of light in a vacuum is supposed to be constant. However, I am having a problem reconciling this fact with the Doppler effects of light. Here's my problem... Let's correlate a propagating beam of light with a moving train. The faster that I move against the...

This is my first post, so if I am in any way out of line for the the norm on this site please forgive and instruct me. That said, I found this site while trying to comprehend a physics issue I just cannot seem to get my head around. That would be the claim that faster than light travel woudl...

Can you go so fast that after say one second, light has traveled less than a Planck length further than you did (with respect to an outside observer of course)? Is c the actual speed limit, or is the speed limit slightly less than c? Maybe I'm not stating this properly and forgive me if...

The Sun is 1.5 x 10^11 m from the Earth. How long does it take for the Sun's light to reach the Earth? Above is the question I have to answer I was thinking... 300,000,000,000 meters/1.5*10^11...dunno?

Hi I am just wondering if E = mc^2 then wouldn't it also be correct to say 1/2mv^2=mc^2 since E is kinetic energy. So in order for an object to travel near light speed, it has travel twice (1/2v^2=c^2) the speed of light according to the above formulae. But according E=mc^2 light speed is the...

Ok I got a question. So we know that in space light travels at a constant speed of 3X10^8m/s. We also know that light can't escape a black hole gravity field. So let's assume I got a light source just near a black hole (lets assume the gravity field is radial) ,my light source is...

I have seen speculation that if the universe is like a computer and/or runs like cellular automata, then the speed of light can be seen as the processing speed of the universe. You can't go faster because the universe can't calculate what will happen any faster than that. I think it may have...

Light travels slower in mediums like water than it does in the vacuum. Would it be even faster in the vacuum if the vacuum were "true" and there were no virtual particles popping into existence? Shouldn't light be slowed by them?

Hi I have a simple question in GR we can claculate the gravitational acceleration of the black hole with the Equation : \[ a = \frac{{GM}}{{r^2 \sqrt {1 - \frac{{r_s }}{r}} }} \] now , the acceleration of a mass which falls into the black hole at the event horizon (when \[ r = r_s...

I'm kind of new to theory and, here is something I thought about, please tell me if I'm wrong. If it takes infinite energy to travel at speed of light, photons that travel at speed of light, must have infinite amount of energy, and if time flow is approaching 0 for the (photon), photon energy...

I have been searching the net for measurements and how they are done of the speed of light. For some reason, I don't find much on them. I see sites promoting various theories whether sped up or down or is not constant. Claiming prehistorical differences in the speed of light is unverifiable I...

for the equation m=m0/relativistic factor m is greater than m0 and about a photon which has a speed that is equal to light's one the mass would be inifinite and so the gravity would be infinity too. or maybe does that increase convert in energy? but if so in the sun as final effect(of nuclear...

i brought this topic up in another forum and as it was a debate forum i didnt get much of an answer but, rather, a lengthy redundant argument between everyone. so I am giving it a try here i don't have much knowledge with physics in general, and relativity is especially rough for me. that...

Source

I'm sorry if this doesn't exactly fit in the topic, but it applies to the general subject I guess. I have been pondering on this question for about a week, and now I want to ask it. Why do we have it so ingrained in us that we HAVE to go the speed of light (or faster) to get anywhere? Assuming...

Hi I have made a discovery - for me that is; it may not be new - and I was wanting to have the knowledgeable soles here tell me if it is correct according to current theory if you could. I will submit it shortly but first off I just want to check one thing. Say you have two planets...

Why can't "forces" travel faster than light speed? As always, I'll start with a disclaimer that I know next to nothing about physics, just that I have an interest in the subject (actually, relativity kinda scares the hell out of me for some odd reason). Anyways, I am reading through this...

In the general theory of relativity the geodesics of spacetime are defined by light rays; the path of a light ray defines the shortest possible path between two points. However, once we remove matter from spacetime there ceases to be a reference frame that separates physical points, so the...

Is there a name for the 'force' that would increase a ships mass as it gets near to the speed of light , hence slowing it down? I was thinking about a spaceship in free space with no gravitational force acting on it, how fast would it have to go before its mass starts increasing?

Something I was wondering, since time slows down as we approach the speed of light. Say a person in a ship travailing close to the speed of light only ages by one hour when the rest of the Earth ages by 100 years, does that mean the ship only uses one hours worth of fuel? But travels 100 years...

Hello, I recently read about neutrinos having mass > 0. (http://news.bbc.co.uk/1/hi/sci/tech/4862112.stm) , but also they travel at the speed of light. How can it be possible? If they have mass, their mass should increase with the velocity, and at the speed of light according to special...

If two objects move away from each other in opposite colinear directions at the speed of light. How long will it take for the light from one of the objects to reach the other? I think the answer is never, but not sure.

say your traveling in a spacecraft at relatavistic speeds, about .700c and you shoot a laser out of the spacecraft (3.00 x 10^8 m/s foward). How was does the light travel. If you do the same thing but shoot it out the abck the oppossite way how was does the light travel. This was a question...

Just read about the advances on traveling at the speed of light. I have a problem about the whole "time travelling" theory. If (or maybe when) the human race can travel at a speed faster than time itself, how could we possibly go back in time? Surely going faster than time would mean that you...

How can a photons velocity be slowed down when they pass through air, water, etc? If photons can be slowed down to slower than light speed, then would it not be possible for a "futuristic lightspeed rocket" to catch up to a photon? And also how can someone measure a slower speed (other than...

Ok. going to be a little hard to ask this question clearly I think. So the speed of light is always constant no matter how fast you are going. So if you were traveling at the speed of light, would the light still be going faster than you at 300,000 km/s (or however fast it is) or would it be the...

If I am to understand correctly, light speed is the speed at which light travels through space. As I also am led to believe, our sun is some four lightyears away. I recall hearing that since it takes roughly four years for light to travel from the sun to us, the light we see during the day...

I'm just thinking that since light is an electromagnetic wave, it must move sinusoidally. So, wouldn't it just be going forward at the speed of "c", while the wave itself would be going up and down as well? And if that's the case, wouldn't the actual speed of the photons be much faster if the...

Question? What would the equation formula be for a Bubble collapsing at the speed of light? I was thinking about Light speed Bubble implosions and had to ask. Do you think this might have merit in any way for Super Fusion techniques? I have an idea of a special Hollow/Spherical Super...

Proof : Light Speed isn't Constant ! Please allow me to show the most conclusive(seems to be) part of my site. Two stars are on the right and on the left. Facing stars, two mirrors are set at 45 degrees, and reflect star's lights to under. Speed of two reflection lights are same always...

What if the center part of a bicycle wheel was spinning at almost the speed of light. What would keep the outside part of the rim from spinning faster than the speed of light?

I was hoping someone could explain to me how if someone travels to a distant point in space at the speed of light and then comes back traveling at this speed, how would the people still here on Earth have aged more than the person that traveled at the speed of light? Thanks

I am trying to understand the twin paradox, so you have twin 1 and twin 2, both on planet earth. The twins are 23 years old and twin 2 leaves on a ship traveling close to the speed of light and then turns around (with or without a instantaneious turn around time?). On his return home twin 2...

I found it interesting when i learned that no matter how fast you are traveling through space, you will alwys measure light to be traveling at the same speed. Then I thought of something: What would happen in this situation. There is a race. The two racers are me, wearing my "light speed"...

Why light itself cannot travel faster than c = 299792458 m/s?

Photon doesn't interact with external force and move with light speed. But why can it act as force carrier, play a role in photoelectric etc.?

Maybe this has been answered before, but when you approach the speed of light what do you see out of your eyes in your frame of reference. Now I have seen websites with animations of what it looks like when you approach c, but I don't understand how you can see what you see like that. I think of...

They say it's so in this science illustrated. If it is so and lightspeed doubles in 2.000.000.000 years, will the sun become 4 times as warm (E = mc2) or what would really happen, would everything contain four times as much energy, would wood burn in blue flames? tell me what!

I recently heard something very interesting. For mass to go light speed, it must be infinite. It can be proved by breaking apart E=MC^2.

Ok I have some general questions about mass and energy. I was wondering if photons have any energy themselves? And if they do, why is it that energy can travel at the speed of light but mass can not (ie, if they are interchangeable why can't mass travel at light speed). Thanks for your time.

Hai.. All says light travels with C.But when it reaches that speed after emiting. I think one can't start with a speed > 0.

I would like to talk about the speed of light and how so many people, even physicists, don't realize that light speed relative to itself is in fact infinite. What I mean by this is if you travel at light speed you in fact travel at infinite velocity, not 300,000 km/s. Is there anyone here who...

Light speed niavety?? Light speed naivety?? -------------------------------------------------------------------------------- The speed of light - c is a fundamental constant, at least in vacuum. However, it appears that c varies and slows down at the interface between different density...

Light speed naivety?? The speed of light - c is a fundamental constant, at least in vacuum. However, it appears that c varies and slows down at the interface between different density materials ie: air to water. But why is this? If a) photons travel between particles and b) the space...

Light speed...Impossible Faster than light..Probable? With all the talk of speed of light and what not i have to ask. Einstien said that to travel at the speed of light required an infinite amount of energy, correct? Einstien also said that it is impossible to go from a velocity of below the...