FTL Communication

[Moontanman]

A point of light, like a laser dot, can be made to travel faster than light. If you projected a dot of light on a distant object you could move the projector at it's source slower than light but the dot it projects could move faster then light.

[freeztar]

Originally Posted by Moontanman

A point of light, like a laser dot, can be made to travel faster than light. If you projected a dot of light on a distant object you could move the projector at it's source slower than light but the dot it projects could move faster then light.

I'm not sure I understand. Can you elaborate?

If I'm reading this correctly, it seems no different than the luminal scissors idea.

[Moontanman]

Originally Posted by freeztar

I'm not sure I understand. Can you elaborate?

If I'm reading this correctly, it seems no different than the luminal scissors idea.

See this link,

Speed of light - Wikipedia, the free encyclopedia

[freeztar]

Originally Posted by Moontanman

See this link,

Speed of light - Wikipedia, the free encyclopedia

I've previously read all of that. I'm still unsure how this relates to your dot idea.

Just to make sure, this is how I envision what you are implying (sorry for the crappy drawing, but a pic is worth words):

[LaurieAG]

Originally Posted by Moontanman

A point of light, like a laser dot, can be made to travel faster than light. If you projected a dot of light on a distant object you could move the projector at it's source slower than light but the dot it projects could move faster then light.

Hi Moontanman,

The link isn't exactly what is being discussed. Are you talking about something like setting up a series of pixels (projected on a distant object i.e. screen) that appears to be something moving FTL? i.e. apparent movement appears 90 degrees to the individual dots being sent.

[modest]

Originally Posted by Moontanman

A point of light, like a laser dot, can be made to travel faster than light. If you projected a dot of light on a distant object you could move the projector at it's source slower than light but the dot it projects could move faster then light.

I agree Moontanman, a laser point like a shadow can move faster than light. They are not physical things and only by considering them a "thing" can we say they move faster than light. As you would no doubt agree, there is no way to communicate with this effect. This discusses it:

Faster Than Light

It also looks like a good site for the rest of the common FTL ideas.

-modest

[Moontanman]

Originally Posted by modest

I agree Moontanman, a laser point like a shadow can move faster than light. They are not physical things and only by considering them a "thing" can we say they move faster than light. As you would no doubt agree, there is no way to communicate with this effect. This discusses it:

Faster Than Light

It also looks like a good site for the rest of the common FTL ideas.

-modest

The site I was talking about says this:

Light spots and shadows
If a laser is swept across a distant object, the spot of light can easily be made to move at a speed greater than c.[14] Similarly, a shadow projected onto a distant object can be made to move faster than c. In neither case does any matter or information travel faster than light.

While it does say that information cannot travel faster than light like this I disagree. If you had a detector on the moon and you swept a laser beam across it you could send something like Morse code faster than light. As you flicked the beam back and forth across the detector it would move on the Moon at the instant it was moved on the earth. Using this to stimulate the detector would allow you to send a digital code instantaneous. OK why not?

[Moontanman]

Originally Posted by LaurieAG

Hi Moontanman,

The link isn't exactly what is being discussed. Are you talking about something like setting up a series of pixels (projected on a distant object i.e. screen) that appears to be something moving FTL? i.e. apparent movement appears 90 degrees to the individual dots being sent.

negatory on that

[modest]

Originally Posted by Moontanman

While it does say that information cannot travel faster than light like this I disagree. If you had a detector on the moon and you swept a laser beam across it you could send something like Morse code faster than light. As you flicked the beam back and forth across the detector it would move on the Moon at the instant it was moved on the earth. Using this to stimulate the detector would allow you to send a digital code instantaneous. OK why not?

No, it still takes like the regular amount of time to get to the moon. What you outline is no different from blinking a laser on and off to construct a message. The speed you blink it on and off or the speed you wiggle it back and forth is independent of the amount of time it takes the signal to reach its destination.

-modest

[Moontanman]

Originally Posted by modest

No, it still takes like the regular amount of time to get to the moon. What you outline is no different from blinking a laser on and off to construct a message. The speed you blink it on and off or the speed you wiggle it back and forth is independent of the amount of time it takes the signal to reach its destination.

-modest

No you misunderstand, the beam is already at the moon. According to the article you can move a shadow or a spot of light faster than the speed of light. If you moved the spot back and forth across the detector you could signal faster than light since the spot moves at the speed of it's source being moved back and forth. At it's source the speed could be just a few feet per second but the spot would be moving faster than light. Before I go any further with this, lets get some basics settled out. While I'm sure I am wrong in this lets see if I have the idea correct. If you had a small rod with a laser coming out of both ends and you caused it to turn in a circle at a few hundred RPS what would the beams look like if you could look down on them from a great distance? (lets assume you can see a laser beam) Would the beams be straight and true as a laser or would they spiral like the arms of a hurricane? If they would be straight then you could move the laser back and forth and at some point the beam would be moving faster than light but in sync with the source. Then you could turn a detector off and on with no time lag from the Earth to the detector. In essence you would signaling faster than light. Yes? No? Why? Why not?