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# Is the light traveling through space or not?

Sun 11 Apr, 2021 09:55 pm
Code:``` L1--------------------X--------------------L2 ```

L1 and L2 are lights. There are 2 ships at X passing each other in opposite directions. L1 and L2 flash simultaneously in the frame of reference that is at rest relative to L1 and L2. For the ship moving towards L1 and away from L2, L1 flashes before L2 flashes. For the ship moving towards L2 and away from L1, L2 flashes before L1 flashes.

When L1 flashes is the light from L2 traveling through space or not traveling through space, in other words, has the light from L2 already been emitted or not yet emitted? When L2 flashes is the light from L1 traveling through space or not traveling through space, in other words, has the light from L1 already been emitted or not yet emitted?
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maxdancona

1
Sun 11 Apr, 2021 11:27 pm
@Fruityloop,
Sigh. I feel like I keep answering the same question over and over again with slightly different wording.

In the first paragraph you specify the frame of reference.

In the second paragraph you don't specify the frame of reference.

That second paragraph is where you are having the problem
Fruityloop

1
Sun 11 Apr, 2021 11:36 pm
@maxdancona,
So what is the answer to the question (s)?
maxdancona

1
Sun 11 Apr, 2021 11:52 pm
@Fruityloop,
We have already been through this. And you already know the correct answer (at least you should by now).

The answer is different depending on the frame of reference. You have already pointed this out in the first paragraph.
Fruityloop

0
Sun 11 Apr, 2021 11:57 pm
@maxdancona,
If the answer is different depending on the frame of reference then that means that both frames of reference are valid and correct and the light is simultaneously traveling and not traveling through space. That is physically impossible. That can't be correct. Therefore special relativity is invalid and wrong.
maxdancona

1
Mon 12 Apr, 2021 12:01 am
@Fruityloop,
You continue to state it is not correct. But it is correct.

Your refusal to accept the way science works does mean it doesn't work.
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maxdancona

1
Mon 12 Apr, 2021 12:09 am
@Fruityloop,
Fruityloop wrote:

.... the light is simultaneously traveling and not traveling through space. That is physically impossible. That can't be correct.

Fruityloop's wording is a little confusing. I don't want anyone to think this has anything to do with Quantum states. It doesn't.

The issue here is the word "simultaneously". Whether two events happen simultaneously depends on the frame of reference. Fruiyloop's is inventing some absolute frame of reference from which we can reduce simultaneity. This is why he is arriving at the wrong conclusion.

Fruityloop

0
Mon 12 Apr, 2021 12:23 am
@maxdancona,
If the light from L2 has been both emitted and not emitted at the moment that L1 flashes depending on the frame of reference how is it not the case that the light from L2 is simultaneously both traveling and not traveling through space?
maxdancona

1
Mon 12 Apr, 2021 01:10 am
@Fruityloop,
I am sitting in Boston. Chicago is West. My sister is in San Francisco. Chicago is East. How can Chicago be both West and East at the same time?

It is a matter of where you are measuring from, or what frame of reference you are using.

I am sitting static in my comfy chair. I am not moving. I am on a planet that is orbiting the sun which is orbiting the galactic central point. I am both moving and not moving.

It all depends on the frame of reference.
Fruityloop

0
Mon 12 Apr, 2021 05:41 am
@maxdancona,
Thanks for the post of irrelevant information.

So to summarize...

At the moment that L1 flashes...
One observer says the light from L2 has been emitted.
The other observer says the light from L2 has not been emitted.
Both frames of references are equally correct and valid.
Therefore, the light from L2 is both emitted and not emitted simultaneously which is impossible.

Or

At the moment that L2 flashes...
One observer says the light from L1 has been emitted.
The other observer says the light from L1 has not been emitted.
Both frames of references are equally correct and valid.
Therefore, the light from L1 is both emitted and not emitted simultaneously which is impossible.
Ragman

1
Mon 12 Apr, 2021 06:25 am
Hello wall.
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maxdancona

1
Mon 12 Apr, 2021 06:27 am
@Fruityloop,

You have a philosophical belief that whatever happens "simultaneously" in one frame of reference happens "simultaneously" in all reference frames.

You provide no evidence for this belief, in fact there is conclusive evidence that this is not true (in the form of Physics experiments that show that confirm relativity).

If this is matter of religious faith for you, then I guess you are stuck.

Because science (i.e. experiments) show that your strongly held belief is wrong.
Fruityloop

1
Mon 12 Apr, 2021 09:24 am
@maxdancona,
For one frame L1 flashes and L2 hasn't yet flashed.
For the other frame L1 flashes L2 has already flashed.
The only way that these events could not be simultaneous is if L1 flashing is not simultaneous in both frames. If L1 flashing is not simultaneous in both frames that means that in one frame the light from L1 is emitted and at the same time in the other frame the light from L1 is not yet emitted. This means that the light from L1 is simultaneously both passing and not passing through space which is impossible.
maxdancona

1
Mon 12 Apr, 2021 09:59 am
@Fruityloop,
You aren't making sense now.

The word "simultaneous" only makes sense when you are comparing two different events.
Fruityloop

1
Mon 12 Apr, 2021 11:10 am
@maxdancona,
The 2 events are L1 flashing in one frame, L1 flashing in the other frame. If the 2 events are simultaneous then the light from L2 is both traveling through space and not traveling through space simultaneously which is impossible. If the 2 events are not simultaneous then the light from L1 is both traveling through space and not traveling through space simultaneously which is impossible.
maxdancona

1
Mon 12 Apr, 2021 11:19 am
@Fruityloop,
It is a fairly simple principle you are getting wrong.

Two events that happen simultaneously in one frame of reference can happen one after the other in another frame of reference.

If you accept this principle, your problems go away.
Fruityloop

1
Sun 16 Jan, 2022 07:52 am
@maxdancona,
Code:``` S1------> L1------------------------------M------------------------------L2 <------S2 ```

L1 and L2 flash simultaneously in the frame of reference that is at rest relative to them. Both ships S1 and S2 arrive at the midpoint M when L1 and L2 flash simultaneously in the frame of reference that is at rest relative to L1 and L2. For ship S1, L2 flashes before L1. For ship S2, L1 flashes before L2. Therefore, at the moment that L1 flashes the light from L2 is simultaneously both traveling through space and not traveling through space which is impossible.

Well, I accepted the principle that 2 events that happen simultaneously in one frame of reference can happen one after the other in another frame of reference and it led to an impossible situation.
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