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Does anyone know why light travels at light speed, and not faster or slower.

Lol, if I sited a video of ufo physics, will that not be visible evidence
a reply to: Arbitrageur

Though I have another ques.
When you angle a solar panel away from the sun ( effectively reducing the projected area facing the sun ), yet keeping the whole surface bathed in sunlight, you still derive less heat or electrical output from the panel. Why is that so? Or alternatively, does it prove the existence of em wave particle, namely the photon?

a reply to: mbkennel

Quantum Field Theory, says something else.

yea, humans can't never agree on one thing, like what is God or moral or how much is enough...

Reality is quantum mechanical functions of functions (the elementary fields).

Reality is mathematical formula ?? I don't think so !!
QM describes mathematically the observable, it's an language and not reality !

originally posted by: Nochzwei
Though I have another ques.
When you angle a solar panel away from the sun ( effectively reducing the projected area facing the sun ), yet keeping the whole surface bathed in sunlight, you still derive less heat or electrical output from the panel. Why is that so? Or alternatively, does it prove the existence of em wave particle, namely the photon?

the surface area perpendicular to Sun gets smaller...
how this could be a proof to anything else than one,
smaller area = less flux

Do PV cells actually convert white light to current or do they work off of shortwave radiation?

nvm

originally posted by: Ares95PL
Does anyone know why light travels at light speed, and not faster or slower.

If it has no mass, then it has zero resistance. Then, in vacuum (know though that light does slow down in a non-vacuum medium), it can't travel below the maximum speed allowed.

And since Special Relativity states that the maximum speed is the speed of light, then light can't travel above this maximum speed.

Thus, in vacuum, light travels at the speed of light.

originally posted by: DenyObfuscation
Do PV cells actually convert white light to current or do they work off of shortwave radiation?

used to be only the visible spectrum while ultraviolet and infrared wavelengths were not converted into electricity but rather wasted as heat. A recent discovery of a new semiconductor material made from indium, gallium and nitrogen can convert virtually the full spectrum of sunlight. And now another process was recently discovered as well using QM.Now this is amazing because you could use the paint on your car to produce energy.Its a spray on solar cell

www.sciencedaily.com...

originally posted by: Nochzwei
Though I have another ques.
When you angle a solar panel away from the sun ( effectively reducing the projected area facing the sun ), yet keeping the whole surface bathed in sunlight, you still derive less heat or electrical output from the panel. Why is that so? Or alternatively, does it prove the existence of em wave particle, namely the photon?

Take it to an extreme angle like 89 degrees and it should be obvious. If the solar panel is say 1 meter squared, you no longer have 1 meter squared of sunlight hitting the panel, it's about 0.017 meter squared of sunlight, spread out over the 1 meter squared panel (so you'd get 1.7% as much power as a panel aimed at the sun).

Since this is just geometry, I don't understand why you think it might prove the photon's existence. What proved that was the photoelectric effect I mentioned here. See the link for more details, but red light wouldn't eject electrons, while violet light would, even if the red light was much more intense.

originally posted by: swanne

originally posted by: Ares95PL
Does anyone know why light travels at light speed, and not faster or slower.

If it has no mass, then it has zero resistance. Then, in vacuum (know though that light does slow down in a non-vacuum medium), it can't travel below the maximum speed allowed.

And since Special Relativity states that the maximum speed is the speed of light, then light can't travel above this maximum speed.

Thus, in vacuum, light travels at the speed of light.

light doesn't slow down at all.
it's path/ velocity changes.
which creates a longer path
correlate path and position.

I was suggesting elongated photons since elongated em wave wouldn't convey the same meaning or be a non sequitor
a reply to: Arbitrageur

originally posted by: krash661
light doesn't slow down at all.
it's path/ velocity changes.
which creates a longer path
correlate path and position.

If you measure the speed of light in air, it's slightly lower than a vacuum, and in glass, the measured speed of light is considerably lower than a vacuum.

But once it's in glass, it travels pretty much in a straight line, and a meter is the same distance in a vacuum, air and glass. So I don't know why you say it's a longer path, it's not. A meter is a meter is a meter and they are all the same length (in the same frame of reference).

This gets a little complicated but I don't know how to simplify it; it's not a longer path, it's an interaction between the photon and the glass which gives light a lower measured speed in glass:

Do Photons Move Slower in a Solid Medium?

Do Photons Move Slower in a Solid Medium?

...This question appears often because it has been shown that in a normal, dispersive solid such as glass, the speed of light is slower than it is in vacuum. ...

The process of describing light transport via the quantum mechanical description isn't trivial. The use of photons to explain such process involves the understanding of not just the properties of photons, but also the quantum mechanical properties of the material itself (something one learns in Solid State Physics). So this explanation will attempt to only provide a very general and rough idea of the process.

Then it goes into a long and somewhat complicated discussion, and they call that the "simplified" explanation, since it's actually more complicated than that. It's a bit long to post the entire thing but those interested can follow the link and read it.

originally posted by: Nochzwei
I was suggesting elongated photons since elongated em wave wouldn't convey the same meaning or be a non sequitor
a reply to: Arbitrageur

I don't think the wavelength of sunlight changes when you change the angle of the solar panel, does it? So what do you mean "elongated em wave"?

originally posted by: Arbitrageur

originally posted by: krash661
light doesn't slow down at all.
it's path/ velocity changes.
which creates a longer path
correlate path and position.

If you measure the speed of light in air, it's slightly lower than a vacuum, and in glass, the measured speed of light is considerably lower than a vacuum.

But once it's in glass, it travels pretty much in a straight line, and a meter is the same distance in a vacuum, air and glass. So I don't know why you say it's a longer path, it's not. A meter is a meter is a meter and they are all the same length (in the same frame of reference).

This gets a little complicated but I don't know how to simplify it; it's not a longer path, it's an interaction between the photon and the glass which gives light a lower measured speed in glass:

Do Photons Move Slower in a Solid Medium?

Do Photons Move Slower in a Solid Medium?

...This question appears often because it has been shown that in a normal, dispersive solid such as glass, the speed of light is slower than it is in vacuum. ...

The process of describing light transport via the quantum mechanical description isn't trivial. The use of photons to explain such process involves the understanding of not just the properties of photons, but also the quantum mechanical properties of the material itself (something one learns in Solid State Physics). So this explanation will attempt to only provide a very general and rough idea of the process.

Then it goes into a long and somewhat complicated discussion, and they call that the "simplified" explanation, since it's actually more complicated than that. It's a bit long to post the entire thing but those interested can follow the link and read it.

well for one, i wouldn't listen to anything by zapperz. most on that site are not even physicist, but yet claim to be.
most on that sit are nothing but students and teachers(not even professors).
also understand that vacuum space means empty.
and no light does not travel in a straight line at all.
look into compton scattering.
and second, again it does not slow down, it's path changes , which is what occurs in the medium.
light flows like a field in all directions it can
if you are on the side of light,
it would not be moving, it would be static.
imagine if a mirror and i (mirror point at me) are traveling at the speed of light
both traveling the same speed of light, the light never reaches the mirror.
so would i be invisible ?
now think about square (c^2)
and another thing,
no it's not complicated at all.

as for a medium, matter,
fields of influence
divide up the conception of the physical world because each existence consists of different layers.
it consists of a material illusion and a sphere of influence.
certain physical conditions are associated only with the realm of the material,
while other and more complicated conditions are associated only with the sphere of influence of the material world.
the conception of the physical world is based upon a simple material illusion
the illusion is further subdivided into three elementary or basic conditions of matter.
a fourth and very important condition also exists,
it is the one bordering on the sphere of influence or plasma realm
a controlled transformation or an elevation of the frequency of matter and the stable existence of this fourth aggregate condition of matter exists at a very primitive level.
there are simply five states of matter.
plasma, i don't mean just "hot gas" (as the concept is generally simplified),
but rather i mean a higher aggregate condition of matter.
the plasma state of matter is a special form of matter which lies between its real existence and the sphere of influence,
that is,
a complete loss of mass and pure accretion of energy of various form whenever matter is "pushed or shoved."
the fourth state of matter is very important for certain physical conditions which can be used to generate antigravity.
essentially, in the world of real physics, there are no bipolar forces, but rather only "observer dependent reflective behavior" of a single, large unified force at different levels.

I mean elongated photon or elongated wave packet was what I was trying to convey. Hence that is why, I was suggesting the existence of photons.
Lol I know very well that wavelength of em wave does not change, when you angel the panels from normal, which I already called a non sequitur
a reply to: Arbitrageur

originally posted by: krash661
well for one, i wouldn't listen to anything by zapperz. most on that site are not even physicist, but yet claim to be.
most on that sit are nothing but students and teachers(not even professors).

If you've got a better source by people you have verified are real physicists which explains it better, then please post that source.

and no light does not travel in a straight line at all.
look into compton scattering.

Did you notice I included the qualifier "pretty much" to make it clear I wasn't claiming every single photon travels in a straight line, specifically to avoid some comment like that? (Yet you made it anyway). When we measure the speed of light in glass, and find it slower than in a vacuum, we are generally measuring the speed of the photons that didn't scatter. Yes some of them do scatter, but you can tell most of them don't when you see the outline of your window on the floor where the sun shines through the window . If the glass was making all the light scatter, you wouldn't get a clear outline. (You can buy glass that's been specially made to scatter the light but that's not the kind of glass I was talking about, and in the case of my bathroom glass I think it's still the same type of glass but it's mostly a surface effect that scatters the light, since the glass doesn't have a flat surface. You can also add impurities to the glass to increase scattering).

Regarding the remainder of your post, you're entitled to question my source and post a better one, but I noticed you provided no source at all and I'd ask that you provide the peer-reviewed papers to support your claims. I didn't follow a lot of that but you got me curious about the five states of matter since solid, liquid, gas and plasma are the four I normally see cited, but I'm not clear on what you're calling the five states of matter.

originally posted by: Nochzwei
Lol I know very well that wavelength of em wave does not change, when you angel the panels from normal, which I already called a non sequitur

OK so far so good.

I mean elongated photon or elongated wave packet was what I was trying to convey.

I'm still lost because given the above this is the non sequitur, maybe I should just quit while I'm behind? I don't think the photon, wave, or wave packet gets elongated when you change the angle of the solar collector. The distance some of the wave packets have to travel before hitting the collector may change, but if you put a swivel in the middle of the collector, then after rotation the average distance traveled is still the same.

After rotating the panel, you've changed the area which the waves or particles can strike, but the waves/particles themselves haven't spread out, if that makes any sense.

originally posted by: Arbitrageur

originally posted by: krash661
well for one, i wouldn't listen to anything by zapperz. most on that site are not even physicist, but yet claim to be.
most on that sit are nothing but students and teachers(not even professors).

If you've got a better source by people you have verified are real physicists which explains it better, then please post that source.

and no light does not travel in a straight line at all.
look into compton scattering.

Did you notice I included the qualifier "pretty much" to make it clear I wasn't claiming every single photon travels in a straight line, specifically to avoid some comment like that? (Yet you made it anyway). When we measure the speed of light in glass, and find it slower than in a vacuum, we are generally measuring the speed of the photons that didn't scatter. Yes some of them do scatter, but you can tell most of them don't when you see the outline of your window on the floor where the sun shines through the window . If the glass was making all the light scatter, you wouldn't get a clear outline. (You can buy glass that's been specially made to scatter the light but that's not the kind of glass I was talking about, and in the case of my bathroom glass I think it's still the same type of glass but it's mostly a surface effect that scatters the light, since the glass doesn't have a flat surface. You can also add impurities to the glass to increase scattering).

Regarding the remainder of your post, you're entitled to question my source and post a better one, but I noticed you provided no source at all and I'd ask that you provide the peer-reviewed papers to support your claims. I didn't follow a lot of that but you got me curious about the five states of matter since solid, liquid, gas and plasma are the four I normally see cited, but I'm not clear on what you're calling the five states of matter.

first,
i do not need a basic physics lesson.
read again my post you quoted.
as for an source , look into actual papers.
for public publishing's(mainstream)
start at arxiv prints.

and second, i'm not interested in arguing,
especially arguing over incorrect nonsense made by others.
this is typical,
want to be intellects/scientist spewing something they have no comprehension of.


edit-
it's the same on all theses places,
it's the usual focused , lack of understanding/knowledge arguing nonsense.
i'm not going to sit here and explain, when no one is seriously interested in learning,
but interested in arguing only.
and it's always from want to be intellects and/or scientists.
same nonsense on this site , like all other physics/science/fringe forums/sites.

a reply to: krash661


Ok looks like you are confused about relativity. Light always travels in a straight path unless a medium scatters it or bends it. As faras the mirror part you cant travel the speed of light and have light stand still it doesnt work that way.To any observer in any frame of reference light will always appear to travel at the same speed. So no you wouldnt be invisible you would see the light bounce off the mirror and return to you the speed your going is totally irrelevant. Any person moving at a constant velocity will observe the same laws of physics that a stationary person would observe. Meaning if your moving at the speed of light you will still see light moving at the speed of light this occurs through whats called time dilatation. Distance is measured by velocity times the time it takes the faster you move the slower time becomes. Or simply put the faster you move the slower you age i always liked looking at it this way i have a poster in my lab says avoid death keep moving with the equation under it.

originally posted by: krash661

imagine if a mirror and i (mirror point at me) are traveling at the speed of light
both traveling the same speed of light, the light never reaches the mirror.
so would i be invisible ?

a reply to: krash661

What 'dragonridr' said is correct. You (krash661) seem to be forgetting time dilation

First of all, according to Einstein, you (or anything with mass) can't move AT the speed of light, because an infinite amount of energy would be needed to get you moving that fast. So, instead, let's say you were moving at 99.999999% of the speed of light.

Back to time dilation...
According to Einstein and the theory of relativity, time for you would move more slowly as you approached the speed of light, and that difference in time would make up the difference in how long it takes for your light to reach the mirror.

So to other people outside your frame of reference, it would take a long time before your light reached the mirror. However, within your 99.999999% speed of light frame of reference, time is moving very slowly, so you think your light reaches the mirror at the normal speed-of-light amount of time.

That's relativity, and that's time dilation.

Here's a video that explains time dilation and how the speed of light is observed by someone moving at large fractions of the speed of light. The video presentation is a bit hokey, but the information is presented clearly (also, I apologize if it makes you watch a short advertisement first):

amusing,
the only thing both of you think you know is what ever link you click on and closely plagiarize and call it a summary in your own words using your own mind.
let alone understanding any of it and what einstein states, or what other pieces are involved.
again,
i do not need a basic physics lesson.
especially a lack of comprehension one.