2
votes
2answers
110 views

Is time nothing but the speed of light (or the light itself)?

With regard to relativistic effects on time, all the examples and explanations revolve around light and its speed. Especially in explanatory situations that explain this using photon clock, it seems ...
1
vote
3answers
135 views

Does this count as moving faster than light?

I'm not familiar with any complicated physics equation, however I do understand some basics. Suppose there is two objects, both of them are moving away from each other in a 3-dimensional space, which ...
0
votes
1answer
82 views

Maximum speed higher than the speed of light

I wanted to ask if higher speed than the speed of light will be discovered, will scientists be able to adjust the special relativity to the new situation? I read that informations transmitted faster ...
-2
votes
1answer
80 views

Travelling at/over speed of light, I fire a laser in front of me. What happens to the light from the laser? [closed]

For a moment, assume that travel at/over the speed of light is possible, and we fire a laser in front of us, what happens to the light emitted from the laser? Would the photons scatter, or would the ...
1
vote
1answer
73 views

What is the speed of light from a star moving towards a observer.? [duplicate]

We can say that in vacuum speed of light is constant. But if the star is moving with a certain velocity does it add that velocity to the velocity of photons emitted out of that star?
-2
votes
1answer
63 views

Driving car with (almost) the speed of the light and switch the headlights on [duplicate]

I'm curious what will happen if we 'drive' a car with (almost) the speed of light, and all of sudden we switch the car headlights on? Will the car headlights ray have double speed (speed of ...
2
votes
0answers
70 views

-Thought Experiment- At superluminal speeds, to what degree would vision be impaired? [closed]

I was thinking about superluminal travel when thinking about advanced civilisations in the future. I was also thinking about the Doppler effect; so I decided to think about how light may be affected ...
2
votes
1answer
84 views

Exeeding the speed of light by adding velocities [duplicate]

Well you know how it's said that things can't travel at or past the speed of light? However, can't they move at speeds greater than the speed of light relative to another object? For example: What ...
0
votes
3answers
204 views

Can internet speed be faster than speed of light?

We send email in order to transfer information and, over time, the technology used to send email improves to send email at faster rate. Since we use the Internet to send information from one place to ...
-2
votes
3answers
107 views

Could a photon travel faster than the speed of light in vacuum?

If the cosmic speed limit is the speed of light in vacuum, then what happens when a photon traveling through space meets gravity? Wouldn't gravity pull on the photon that's already traveling at max ...
1
vote
4answers
507 views

What will I see in this scenario? Will this be faster than the speed of light?

Let say there's a particle that is travelling very near the speed of light. Lets say I have a camera capable of filming this high velocity particle and I film the particle on my camera then I fast ...
0
votes
1answer
48 views

speed of the light emitted from a fast moving object [duplicate]

Would not speed of the light emitted from the front of the fast moving object be the speed of light + the speed of the fast moving object?
1
vote
1answer
67 views

Distance and time measurement in the famous Superluminal Neutrinos Experiment

I tried to understand the technical aspects of the OPERA/CERN experiment, but apparently it takes some professional experience. Therefore I would like to ask someone better acquainted with such ...
0
votes
0answers
23 views

Transfer of energy faster than the speed of light [duplicate]

In a vacuum: On my left I have a rod that is 558000 miles long (3 light seconds). A button is secured to its end which activates a laser beam sent back to me once I've pushed the rod in the ...
0
votes
2answers
126 views

Does this* refraction experiment correctly conclude faster than light travel?

This question asks if a particular experiment is correct in its conclusion. This experiment, conducted by Alfred Leitner, is shown in a 1975 physics instructional movie. It claims that the experiment ...
10
votes
1answer
331 views

Why can't I use Bell's Theorem for faster than light communication?

I read this description of Bell's theorem. I understand he's restating it slightly, so there may be incorrect assumptions there, or I may have some. I think Bell's theorem should lead to FTL ...
0
votes
0answers
117 views

Theoretically if you passed the speed of light, would there be a sonic boom equivalent?

I know that it is technically impossible to reach the speed of light since the mass of the object traveling would reach infinity. Despite this if it were possible, would there be some sort of ...
0
votes
3answers
74 views

Question about relative speeds on a different “scales of perception”

I was kind of puzzled yesterday when thinking about this. If we observe an object moving away from us with 10m/s we would say the object is moving away from us really slowly But if we (humans, ...
-1
votes
1answer
223 views

Why light can't go faster then 300 000 km/s? What prevents it? [duplicate]

Why can't the speed of light be faster then approx 300 000 km/s? What prevents it?
1
vote
2answers
165 views

A vertical variation of modern versions of Michelson-Morley

For almost a year now, I have been in the uncomfortable position of having an idea. However, there is one nice thing about this idea. It makes a concrete, exact and relatively easy to test physical ...
0
votes
2answers
194 views

Why is light speed the limit? [duplicate]

Why is the light speed a limit? Why can't anything go faster than light? Not even a single atom?
3
votes
1answer
151 views

Is there a way to increase the speed of light itself?

When light enters materials it slows down due to its refractive index (due to absorbing and re-emission of photons). But, is there a way to increase the speed of light itself? Can there be some ...
0
votes
2answers
370 views

Nothing can travel faster than the speed of light. In what frame of reference? [duplicate]

Since frames of reference are arbitrary, I can define a frame of reference that moves backwards with a speed greater than $c$, then any static object in that frame of reference is already traveling ...
-1
votes
1answer
106 views

If the universe can expand at a speed faster than that of light, why don't we feel the effect? [closed]

the universe, as I have read, is capable of inflating at a speed faster than that of light! How is that even possible if we don't feel the effect? or does it affect us?
3
votes
4answers
454 views

What does 99.9% speed of light mean when there is no absolute velocity?

So when people say: 'I am approaching the speed of light, and to get to 100% light I would need infinite energy' they are essentially saying that this situation is impossible? I read this in ...
-5
votes
1answer
159 views

Faster than light possibility? [duplicate]

According to general relativity, speed is relative, so for example if you are running at 20 km/h and a car passes you at 30 km/h, the runner is actually moving at 50 km/h relative to the car. Now ...
1
vote
4answers
247 views

How can I explain this fallacy of conveying information faster than Light?

First statement of this question: In superluminal phase velocities, what is it that is traveling faster than light? says that information cannot be transmitted at a velocity greater than speed ...
1
vote
2answers
153 views

Variance in speed of light

While discussing this question (Does light have an unending journey?) I stumbled on the fact that light's speed is constant only in inertial frame. What I happened to do was add up the expansion of ...
1
vote
1answer
163 views

Speed of approach between image and object

A plane mirror image approaches the object at the same rate the object approaches the mirror. So the speed of approach is twice the speed at which the object approaches the mirror. If the object ...
37
votes
6answers
3k views

If I am travelling on a car at around 60 km/h, and I shine a light, does that mean that the light is travelling faster than the speed of light?

The title says it all. If I was on a bus at 60 km/h, and I started walking on the bus at a steady pace of 5 km/h, then I'd technically be moving at 65 km/h, right? So my son posed me an interesting ...
2
votes
1answer
216 views

Isn't the front edge of a wave, kind of “information” which travels faster than light?

Considering the definition of phase and group velocities, We know group velocity can't exceed C but phase velocity can be infinitely high. Assume a monochromatic electromagnetic wave traveling with a ...
0
votes
3answers
98 views

Please explain me this relativistic occurrence [duplicate]

So, for example, we have the planet, a spaceship (cylinder shaped) and a ball in it (spaceship is like transparent so we can see the ball). We are on the planet looking at the ship. The spaceship ...
2
votes
1answer
194 views

Faster than light in plasma

Some plasmas have a refraction index of less than 1. In these plasmas the phase velocity of light can be faster than light-speed. But the phase itself won't transfer information, so no paradox occurs ...
-3
votes
1answer
220 views

Einstein's Cosmic Speed Limit $c$ challenged by Black Holes/Massive Objects [duplicate]

To even suggest the great Einstein is incorrect on anything he has written is inconceivably absurd. Being fully aware of this I do indeed dare to not only suggest he is wrong but I cannot believe ...
19
votes
2answers
691 views

Gravitational slingshot of light using a black hole/massive object

Wikipedia has this page on gravity assists using planets. In some cases this effect was used to accelerate the spacecraft to a higher velocity. This diagram shows this in a very oversimplified manner. ...
-5
votes
2answers
2k views

Do radio waves go faster than the speed of light? [closed]

My science teacher used to say a lot of weird stuff, but I'm just making sure on this one.
0
votes
1answer
155 views

Can a pushed plank beat light and break the laws of physics? [duplicate]

Imagine you are one lightyear away from a photon sensitive (light sensitive) switch. So it is obvious that light would take one year to reach to the switch. Now I have a one lightyear long plank. I ...
3
votes
2answers
182 views

Superluminal particles with causality

What kind of CLASSICAL theories would allow to true (non-apparent) superluminal particles (beyond speed of light, BSOL) agreeing with causality to exist? I mean, are causal superluminal classical ...
1
vote
1answer
3k views

Could the shadow move with faster-than-light speed? [duplicate]

If I make a huge laser with a figure for shadow in front of the laser, and I shine it on to the moon, will I see the light from the laser AND the shadow moving the same speed? (I read somewhere the ...
1
vote
3answers
230 views

Stuff can't go at the speed of light - in relation to what? [duplicate]

We all know that stuff can't go faster than the speed of light - it's length becomes negative and all kinds of weird stuff happens. However, this is in relation to what? If two objects, each moving ...
0
votes
3answers
273 views

Is there absolute proof that an object cannot exceed the speed of light?

Have any known experiments ruled out travelling faster than the speed of light? Or is this just a widely accepted theory?
4
votes
2answers
625 views

Can a dot of light travel faster than the speed of light? [duplicate]

Say I have a laser. If I spin the laser so that the beam sweeps in an arc along a very distant object, could that dot travel faster than the speed of light? In Diagram form:
1
vote
4answers
542 views

Has anyone ever measured the one way speed of light perpendicular to the Earth at the Earth's surface?

1 - Has anyone ever measured the one way speed of photons traveling perpendicular to the Earth at the Earth's surface? 2 - Given our current understanding of Physics is there any way both the upward ...
5
votes
2answers
406 views

What if a faster-than-light particle is found?

What will be the consequence (severe ones) on laws of physics if a particle that travels faster than light is discovered? I am looking for a more general answer so that a high school student would be ...
0
votes
1answer
45 views

How the effect travel's? [duplicate]

Let us assume that we placed lot's of ball touching each other in a hollow cylindrical tube, now if we push one ball at the end the ball at the other end move's instantly. So how do the information ...
8
votes
3answers
772 views

Can something travel faster than light if it has always been travelling faster than light?

I know there are zillions of questions about faster than light travel, but please hear me out. According to special relativity, it is impossible to accelerate something to the speed of light. However, ...
0
votes
1answer
507 views

Faster than the speed of light and future travel [closed]

I had read somewhere that if a person attains twice the speed of light, he can actually reach the future. But since the world belongs to one time and space, how will it change for one particular ...
5
votes
3answers
567 views

Extended Rigid Bodies in Special Relativity

I was reading Landau & Lifshitz's Classical Theory of Fields and I noticed that they mention that an extended rigid body isn't "relativistically correct". For example, if you consider a rigid ...
16
votes
2answers
3k views

Is the “How to break the speed of light” minute physics video wrong?

I am referring to this video, on YouTube, by minutephysics, which has quite a lot of views. In the video it states that if you flick your wrist while pointing a laser that reaches the moon, that the ...
5
votes
2answers
930 views

Is 2.5x speed of light possible between two objects?

These news are in Finnish: http://www.hs.fi/ulkomaat/Kaukaisin+havaittu+galaksi+et%C3%A4%C3%A4ntyy+maasta+valoa+nopeammin/a1305618680897 The main excerpt is: "Distant galaxy moves away from us as ...