Star triangle paradox

[John99]

You're still avoiding answering the questions directly. As for environment, assume a vacuum. (Something you could have done in your answer, such as "Assuming the light is crossing a vacuum...").

Saying that light is something like a string isn't an answer. In what way? What exact properties does it share with a string? This is what I'm trying to get you to answer.

Say you have a 6 foot length of string coiled up tight. Take one end of the string and pull it to form a straight A (beginning) to B (end) line. Once the string end reaches point b is it still moving? no it is not moving, it cannot move...forward obviously but that goes without saying since light only travels outward, discounting any other factors, as well.

Reflective Surfaces

This is another topic in and of itself. Now we run into separate issues. Reflectivity is going to alter the light and some surface will absorb some of the ligh kind of like a sponge absorbs water.

 

[Read-Only]

Excuse me but you say it takes 8 minutes to reach here, i dont think i ever said i had an issue with that. If i did it was a mistake of articulation.



Everyone knows that. I also said the light reaching as far as it can go due to the light source itself? Are you telling me that a double A pen light will reach as far a the sun? No, of course you arent.

Of course it will reach the Sun - and beyond. Not all of the photons will due to spread/scatter but SOME of them certainly will.

They shoot a laser *very* frequently at the moon and hit a reflective target one of the Apollo missions set up. a good part of that beam bounces back and is picked up by detectors here on Earth. A good part of the light is lost because even a laser beam spreads some at that distance - but a good part of it travels in a perfectly straight line.

The whole point is that a photon will travel in a perfectly straight line forever and at ANY distance unless it's acted upon by another force or object. For example, being absorbed by matter, reflected or bent by a gravitational field. Otherwise, John, there is NO limit to how far it can travel - unlike your string.

 

[NMSquirrel]

do photons exist by themselves?
can other particles incorporate photons to create other particles?

i think other particles can degrade into photons, most other elements do not really disappear they just disassemble and combine with other particles to form different particles,
no wait..the process of dis/assembly would create photons, pry cause photons are related to energy, not mass, (wave vs particle)

<if it ain't obvious,don't count the squirrel as an expert..>

 

[billvon]

No it is not like the door scenario.

Yes, it is. In all three cases, the only thing that differs is the timing. Light travels about a foot per nanosecond, whether you are three feet, 200,000 miles or 93 million miles from the source - and whether that light is direct or reflected.

This is not easy for everyone to understand.

Apparently!

 

[James R]

John99:

You haven't replied to post #133. Please reply.

 

[Janus58]

Say you have a 6 foot length of string coiled up tight. Take one end of the string and pull it to form a straight A (beginning) to B (end) line. Once the string end reaches point b is it still moving? no it is not moving, it cannot move...forward obviously but that goes without saying since light only travels outward, discounting any other factors, as well.

Reflective Surfaces

This is another topic in and of itself. Now we run into separate issues. Reflectivity is going to alter the light and some surface will absorb some of the ligh kind of like a sponge absorbs water.

And what happens with this "light as a string" when you turn off the light source?

 

[John99]

Of course it will reach the Sun - and beyond. Not all of the photons will due to spread/scatter but SOME of them certainly will.

They shoot a laser *very* frequently at the moon and hit a reflective target one of the Apollo missions set up. a good part of that beam bounces back and is picked up by detectors here on Earth. A good part of the light is lost because even a laser beam spreads some at that distance - but a good part of it travels in a perfectly straight line.

My response contends that we are able to see the source, in this case it is the sun. I stand by my answer:

We would know immediately. I say that for every similar instance.

Here is the actual statement you made:

" John, if the Sun exploded this very moment, it would take 8 minutes for the flash from that explosion to reach your eyes."

I think the problem is "the flash". You say reach my eyes but what you really mean is to reach earth. My eyes are seeing far beyond the surface of the earth.

As an aside, not all light sources travel the same distance. Are you saying a pen light in space goes as far as light from the sun?

 

[AlexG]

I think the problem is "the flash". You say reach my eyes but what you really mean is to reach earth. My eyes are seeing far beyond the surface of the earth.

Your eyes are seeing photons which have reached earth and your eyes. You don't see anything until the light reaches your eyes. Your eyes to do not reach out anywhere. They wait till light comes to them.

 

[John99]

John99:

You haven't replied to post #133. Please reply.

Give me time to go look at it again. We are going through a lot of information that overlaps into that door example. Right now we are attempting to reach definitive conclusions. These things take time...and dont give me a time limit.

 

[John99]

Your eyes are seeing photons which have reached earth and your eyes. You don't see anything until the light reaches your eyes. Your eyes to do not reach out anywhere. They wait till light comes to them.

Oh reallly?

So what if the light source is unidirectional? What if that uniderectional light source is lighting an object? You wont see that object because the light from the source is not reaching your eyes? Key word is reaching and that implies actual contact with the eyes. In other words the light is reaching me. This is a major point of contention here.

 

[origin]

I think the problem is "the flash". You say reach my eyes but what you really mean is to reach earth. My eyes are seeing far beyond the surface of the earth.

Good god, that is scary! You see photons that have not reached the earth? How is that possible? How do you think eyesight works?

Just out of curiosity do you think if someone is next to you looking at the sun through a telescope (don't forget your solar filter!) and the sun were to explode that the guy looking through the telescope would suddenly exclaim something like "Holy crap, you are going to see one heck of an exlplosion in a minute or 2"!

 

[AlexG]

Oh reallly?

Yes, really.

You don't see anything until the light from the object reaches your eyes.

 

[origin]

Oh reallly?

So what if the light source is unidirectional? What if that uniderectional light source is lighting an object? You wont see that object because the light from the source is not reaching your eyes? Key word is reaching and that implies actual contact with the eyes. In other words the light is reaching me. This is a major point of contention here.

What in the name Ra are you talking about? Does that paragraph actually make sense to you!

 

[billvon]

My response contends that we are able to see the source, in this case it is the sun. I stand by my answer: We would know immediately. I say that for every similar instance.

Ah. That's trivial to disprove. Manmade vehicles have reached very close to the Sun (inside the orbit of Mercury) and we can measure the time it takes for radio signals (i.e. photons) to travel from the vehicle to the Earth. They take about 6 minutes to reach us.

The latest vehicle, Messenger, has a high power transmitter it uses to transmit data to the Earth. It shuts down when not in use to save power. When it does send a message and then shut down at the end of it, we continue receiving those photons for six minutes after the transmitter has been turned off. Once it turns back on and starts transmitting again, we hear nothing for six minutes until the new photons reach us.

" John, if the Sun exploded this very moment, it would take 8 minutes for the flash from that explosion to reach your eyes." I think the problem is "the flash". You say reach my eyes but what you really mean is to reach earth. My eyes are seeing far beyond the surface of the earth.

Yep. But they only see photons, which only travel at the speed of light. Any devices you use to assist them (telescopes, cameras and monitors, even remote telescopes that send their data back via radio waves) are also limited by the speed of light. So the soonest you will ever see that flash is 8 minutes.

 

[John99]

Yes, really.

You don't see anything until the light from the object reaches your eyes.

How about your vision reaching the source? can be the source of light or the object being illuminated.

In the unidirectional example the light is hitting an object, we see the object from the light source. What if the light bouncing off the object is not enough to reach the earth whereas the light is noticeable?

 

[AlexG]

How about your vision reaching the source? can be the source of light or the object being illuminated.

In the unidirectional example the light is hitting an object, we see the object from the light source. What if the light bouncing off the object is not enough to reach the earth whereas the light is noticeable?

Your vision doesn't reach anywhere. Light comes to you eyes, your eyes do not travel to the light.

If light from a unidirectional source hits an object, our eyes see the object via the photons which bounce off the object to reach us. In that case, the object is emitting the photons we see, not the unidirectional source.

 

[John99]

In that case, the object is emitting the photons we see, not the unidirectional source.

How do you know the photons are reaching us? Give an example, show me a link that shows this to be true. Just saying "because we see it", which is probably your response, but that is not good enough of an answer.

Right now you are not giving any evidence and then i would ask...would some view this as trolling? Not me, i dont really care.

 

[AlexG]

saying "because we see it", which is probably your response, but that is not good enough of an answer.

Dingaling, how do you think your eyes work? They respond to light. If the light hasn't reached your eyes, they don't see. If they see, it's because the light has reached them, and the cones and rods in you eyes respond to the photons.

Are you really that clueless?

 

[John99]

Dingaling, how do you think your eyes work? They respond to light. If the light hasn't reached your eyes, they don't see. If they see, it's because the light has reached them, and the cones and rods in you eyes respond to the photons.

Are you really that clueless?

Enough with the adhominems.

Did you ever think that your eyes are just seeing the photons?

"Reaching" has a different implication and that is where the issue stands. Add something we can sink our teeth into, dont just come here to brown nose.

 

[origin]

Did you ever think that your eyes are just seeing the photons?

Do you mean that our eyes can see the photons way off in the distance?