What Governs the Speed of Light Itself?

[Pengwuino]

I hope we're not confusing anyone with our argument over symantics/symantecs (whatever the word is that isn't a virus protection company).

 

[DaveC426913]

I hope we're not confusing anyone with our argument over symantics/symantecs (whatever the word is that isn't a virus protection company).

My concern as well. I tried to address the OP's question via analogy in post #23.

 

[russ_watters]

When I say "logic" I mean exactly that: no more, no less. Logic is content-free, with regards to the physical world.

Expansion: most people think SR is illogical at first glance, but the reason is that most people don't see that the logic is only as good as the starting premise. If the starting premise is flawed (as it is with Newtonian physics), then good logic will lead to wrong conclusions. So the converse is that SR is illogical only if you try to figure it out using the wrong starting premise.

 

[Pengwuino]

Expansion: most people think SR is illogical at first glance, but the reason is that most people don't see that the logic is only as good as the starting premise. If the starting premise is flawed (as it is with Newtonian physics), then good logic will lead to wrong conclusions. So the converse is that SR is illogical only if you try to figure it out using the wrong starting premise.

Yes, exactly what i meant. Thank you for condensing my 2 pages of confusion into a coherant statement.

 

[GOD__AM]

A spot of light is a thing, if you ask me. If you want to argue about whether it is really the "same" spot as it moves across the moon's surface (since it is made up of different photons at different times), then we can have that philosophical discussion. We can also argue about whether you are the same person today as you were when you were 3 years old, because all the cells in your body have probably been replaced since then.

But it's all beside the point. My initial post was unambiguous.

No your initial post is just plain wrong. Apply the word "thing" to a spot of light if you must, but understand that the only movement taking place is photons moving from the light source to the moon and back to the observer (and traveling at C not above). No photons move sideways (that the observer can see) you are simply creating a set of events that happens faster than the speed of light. No philosophical discussion required.

 

[cliowa]

Saying the speed of light is frame-independent is not equivalent to saying that c is an upper limit (without the framework of SR).

I'm sorry, I obviously didn't make myself clear: That's not what I meant to say, I agree with you.

All explanations of physical phenomena must follow from some theory. Please explain anything to me without using the results of some theory.

I couldn't agree more. I just feel it's a little weird that so many here are claiming the upper speed limitness of light as LOGICAL, as if it was the most natural thing. The fact that SR is self-consistent doesn't make it logical, in my opinion. Would those of you, who consider this whole thing "logical" also call Quantum Mechanics a "logical" thing? Would you call the entanglement (the EPR paradoxon) for example "logical"?

Take a look at this:

One cannot go faster than the speed of light simply due to logical reasoning. That is, if one were to take into account the theory of relativity, which states that, the closer you get to the speed of light, the faster the world moves around you and the slower you move relative to the world (i.e. the less you progress through time). That having been said, the logical inference to make is that when you hit a point past the speed of light, you will begin to go back in time relative to the world around you, though the world around you should actually begin to go slower and slower the faster you go after surpassing the speed of light.

And now? So what? In QM you go back and forth in time just like you want. The theory works quite well. QM is self-consistent. Is this the third kind of logic, the very new one?

Now, to bring an end to this, here's the definition of "logic" wikipedia:

Logic (from Classical Greek λόγος (logos), originally meaning the word, or what is spoken, but coming to mean thought or reason) is most often said to be the study of arguments, although the exact definition of logic is a matter of controversy amongst philosophers (see below). However the subject is grounded, the task of the logician is the same: to advance an account of valid and fallacious inference to allow one to distinguish good from bad arguments.

So, it's all about concluding, getting a series of good arguments to culminate in one conclusion. THE PROBLEM (of this thread) IS THAT THERE IS NOW ANSWER TO THE QUESTION "WHY STOP AT THE SPEED OF LIGHT?". THERE IS NO REASON. THAT'S JUST THE WAY IT IS, IT SO HAPPENS. IT'S A PURE FACT WE HAVE TO LIVE WITH. PHYSICS DOESN'T ASK WHY SOMETHING IS BUT HOW SOMETHING IS.

Best regards...Cliowa

 

[HallsofIvy]

I hope we're not confusing anyone with our argument over symantics/symantecs (whatever the word is that isn't a virus protection company).

I believe you are looking for is "semantics".

 

[James R]

GOD__AM:

No your initial post is just plain wrong. Apply the word "thing" to a spot of light if you must, but understand that the only movement taking place is photons moving from the light source to the moon and back to the observer (and traveling at C not above). No photons move sideways (that the observer can see) you are simply creating a set of events that happens faster than the speed of light. No philosophical discussion required.

I completely agree with you, except for your claim that my first post was wrong. I was very careful to qualify my statement by saying that no material object can ever move faster than light. Also, I did not claim that individual photons can move faster than light.

Please re-read my first post if you still have doubts.

 

[Jeffro]

Well in regards to the original post:

If most relativity theories are true, something of mass cannot travel fast than light speed 'relative' to other masses. Strange time compression/expansion effects are required to make this work.

However, let's say something (ie. something of mass) can go faster than light and the relativity theories are wrong...then it would pretty much behave as sound does. One would break the 'light barrier' when surpassing lightspeed, which would probably create some type of luminance 'boom' equivalent to the objects mass.

Who knows though. I want to see experiments.

Jeffro

 

[DaveC426913]

Well in regards to the original post:

If most relativity theories are true, something of mass cannot travel fast than light speed 'relative' to other masses. Strange time compression/expansion effects are required to make this work.

However, let's say something (ie. something of mass) can go faster than light and the relativity theories are wrong...then it would pretty much behave as sound does. One would break the 'light barrier' when surpassing lightspeed, which would probably create some type of luminance 'boom' equivalent to the objects mass.

Who knows though. I want to see experiments.

Jeffro

You want experiments??

Special Relativity is one of the most rigorously tested theories in all of science, and it has passed with flying colours every time. It is more plausible that the Earth is only 6000 years old than that SR is wrong.

 

[leon1127]

there is a case that light can go faster than the constant c. It was found in an experiment that when the light go into some matter that the index of refraction is low then where it is from, it accelarates. But the condition is that the light goes faster than c won't be able to contain any information, which is meaningless. Relativity also have stated such condition.
(I read that in a book, but i don't remember what that book is, and that book was in chinese. But i will still look it up again.)

 

[Pengwuino]

I believe you are looking for is "semantics".

pff, they need to change the dictionary so it matches up with my spelling. However thered probably have to be 5 different versions of every single word

 

[Pengwuino]

there is a case that light can go faster than the constant c. It was found in an experiment that when the light go into some matter that the index of refraction is low then where it is from, it accelarates. But the condition is that the light goes faster than c won't be able to contain any information, which is meaningless. Relativity also have stated such condition.
(I read that in a book, but i don't remember what that book is, and that book was in chinese. But i will still look it up again.)

I read something LIKE that... but it wasnt the same end result. There were experiments to make something go faster then light by doing roughl the same thing but they made it clear it was going faster then light, not "c" simply because light's speed had been reduced below 300,000km/s

 

[leon1127]

I read something LIKE that... but it wasnt the same end result. There were experiments to make something go faster then light by doing roughl the same thing but they made it clear it was going faster then light, not "c" simply because light's speed had been reduced below 300,000km/s

well... then that is different experiment then. mine was pretty much say everything obey relativity. And causality will not hold if anything go faster than C because it won't contain information.

 

[GOD__AM]

GOD__AM:



I completely agree with you, except for your claim that my first post was wrong. I was very careful to qualify my statement by saying that no material object can ever move faster than light. Also, I did not claim that individual photons can move faster than light.

Please re-read my first post if you still have doubts.

Yes it was worded carefully, and I will reascend my comment that your first post was wrong. However attributing movement to a spot of light as you did in one of your posts is inaccurate. I would compare it to your mouse pointer, while it appears to move across the screen we all know it's an illusion created by varying the color of the pixels.

I just don't like the example you used, and I think it only leads to confusion. Even in the above reply you still seem to attribute movement to the non material object (the spot of light) and it's my contention that it doesn't move any more than images on your computer screen do.

I apologize for my statement about your post and I know you didn't say any photons go faster than light, I just felt I needed to add that in my description to be accurate.

 

[James R]

Fair enough, GOD__AM. I don't want to labour the point any more than necessary, but I think most people would say the mouse pointer on their computer screen move, even though they might know that this is caused by lighting up different pixels in turn as the pointer moves across the screen. I'm really just following the descriptions people often use.

 

[remix220]

It is not true that nothing can go faster than light. For example, if you point a flashlight at the moon, then you can sweep the beam across the moon's surface in a fraction of a second. Work out the speed of the spot from the flashlight as it crosses the moon's surface, and you'll get an answer greater than the speed of light.

What is true is that that no material object (with mass) can ever be accelerated to the speed of light. (The spot on the moon is not a material object.)

The reason you can't accelerate an object to the speed of light is that you'd need to provide an infinite amount of energy to do that, and an infinite energy source isn't available.

This is funny. You say "It is not true that nothing can go faster than light", however you still use light as an example.
I see what the point is though, I just had an urge to quote this. As far as I'm concerned, if a "infinite" really truly exists (Which I have a REALLY hard time with that), than there is full proof right there that the "normal" speed of light can be overcome. When I think of the big bang, and the "present now", I see this big ball of universe getting bigger, so I would think that the speed of the universe may just be more faster. "Time" itself, is a good example. How fast is time? Time must be faster then light if "Infinite" exists. However, since time is a dimension, dose a dimension even have a size? I feel I could go on forever!

Please QUOTE me! I'm only 16 years old in the lowest science class. Please use... "understandable" terms and examples please! I MUST KNOW THIS!

 

[gmax137]

Why can nothing(in theory) go faster that light.

what is stoping it and what governs the speed of light itself?

?

I don't think anyone ever really answered the third question, "what governs the speed of light itself?"

Isn't it really related to the scaling between the space dimensions and the time dimension? There's some kind of factor of "c" between them... I can't explain this very well... But it isn't a property of light, per se, it's how fast things go if they have no mass. Does that make any sense? Maybe one of you guys can explain this better. Or point me to a thread where it really is answered.

Thanks

 

[pallidin]

I don't think anyone ever really answered the third question, "what governs the speed of light itself?"

Isn't it really related to the scaling between the space dimensions and the time dimension? There's some kind of factor of "c" between them... Thanks

Well, that certainly sounds interesting. You may have something there.