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The Fastest Camera Ever Made Captures 100 Billion Frames Per Second
Jason Koebler writes A new imaging technique is able to capture images at 100 billion frames per second—fast enough to watch light interact with objects, which could eventually lead to new cloaking technologies. The camera was developed by a team at Washington University in St. Louis—for the team's first tests, it was able to visualize laser pulse reflections, photons racing through air and through resin, and "faster-than-light propagation of non-information." It can also be used in conjunction with telescopes and to image optical and quantum communications, according to lead researcher Liang Gao.
Don't tell Peter Jackson
No... no it isn't. And no you can't. And no they won't.
yup thats exactly how i feel
World's Fastest Camera Captures 4.4 Trillion Frames Per Second August 14, 2014
http://tech.slashdot.org/story...
and 180 x 96 picture elements. Wake me up when it's 4k rez.
ever made , that article you referenced speaks of a paper on a design-- not built
Did I just read "faster than light" ?
nm
It looks like a Samzenpus. Shields up!
Another technique exists two years ago: http://www.ted.com/talks/ramesh_raskar_a_camera_that_takes_one_trillion_frames_per_second?language=en
"faster-than-light propagation of non-information" -- Politicians will looove that technology
Table-ized A.I.
Didn't MIT already show off their Femtosecond camera in a TED talk a few years back? That's 1 trillion per second, so this new one is slower!
They wanted to make the distinction that "things" can travel faster than light, but not mass or information.
Learn to love Alaska
What sort of things are there that aren't mass, energy, or information?
you know, love or something, it's the latest fad in the movies like Interstellar.
You can't handle the truth.
Youtube is going to need to dramatically increase their server capacity. There's a lot of non-information posted there.
-- I have monkeys in my pants.
Time to repurpose the interferometer to try all the old experiments, especially Michelson-Morley one.
But the costs for developing all that film would be outrageous..
http://en.wikipedia.org/wiki/P...
Event horizons.
Picture scissors. The edges come together as they close. So increase the size of the scissors, and the speed you close them. Eventually the "point" where the scissors come together will eventually go faster than the speed of light.
It's "real". It's visible. And it isn't mass, energy, or information.
If you don't like that, take a laser. Point it at a cloud. Move the light as fast as you can. The point of light (as seen as the reflection on the cloud) can travel faster than the speed of light.
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http://slashdot.org/comments.p...
No, not love. I thought techies on a tech site would have learned something in physics class. What are they teaching these days, and is there an opening for roman_mir?
Learn to love Alaska
Imagine a powerful, hand-held laser that you can point at the moon and see the reflection. Point it at the far end of the surface of the moon. Now flick your wrist, sweeping the laser across the surface of the moon within 1/100th of a second. The reflected dot will _appear_ to move faster than the speed of light. That is, it will appear to move smoothly* across 3476km (the diameter of moon) of the surface in 1/100th of a second. The speed of light is 299792km/second, and the dot moved at 347600km/second. In other words, it appeared to have moved faster than the speed of light.
Actually, there's really no need to italicize the word appear, I guess. There is a dot and it is moving (even if you define it as a series of discrete reflections, they're all causally related). It's just not the kind of "thing" that can convey information. You can't encode any information in the movement that conveys information to an observer faster than the speed of light.
* You may need to use time-lapse video. I just used the moon as an example because it's concrete. If the moon were larger and farther, the sweeping motion of your wrist could be slower.
Why can't you encode information by changing the speed at which you flick your wrist? At one wrist-flick speed, the dot travels at one multiple of the speed of light; at another wrist-flick speed, the dot travels at a different multiple. The receiver tracks the dot and decodes the speed changes into bits or other representations of information.
Say you entangle two particles, and separate them by a long distance. You measure your particle, and know what the other particle will read when it is measured. You now have information on what the other side will see, when they measure the particle.
If you also know some other things about the other side, that it's a deterministic computer, say that will execute a certain action upon reading a "1" and another action upon reading a "0", you now know what the computer at the other side is doing, after you've measured your particle. You know this instantaneously. You know what the other side is doing, you can predict it. And you can devise your own reaction.
Say you know the computer on the other side will launch an attack in one quarter upon reading a zero, and in another quarter upon reading a one. You measure your particle; you now know which quarter the attack will take place, and you can prepare for that.
How is that not information gained at the speed of entanglement, i.e. faster than the speed of light?
Who said anything about "energy"? he said "mass" or "information"
Emphasis on _appear_. As the laser point speeds over the surface, less and less photons actually hit any particular spot at which laser is at any particular moment, this is directly proportional to speed at which the point moves. As the speed of approaches the speed of light, the point will actually look like its skipping, instead of moving smoothly as no photons have reached the surface of the moon at that time. Since the motion is not continuous speed of light doesn't quite apply as the limit.
This could be trivially demonstrated at home by moving a water drip over clean and dry surface: the faster you move the less water end on the surface and the further away drops are spaced.
For a receiver situated on the moon, limited by the speed of light between him and his tracking devices (which are also situated on the moon), this part gets a little tricky, doesn't it? (i.e., "tricky," I mean "impossible.")
I should add that while it cannot convey any information faster than the speed of light, the faster-than-light motion (or propagation) _can_ be used to do useful stuff. For example, secure information, such as avoid MITM.
I'm not a physicist so can't explain it well, but because apparent motion can be faster than the speed of light, you can encode information in the movement (e.g. alternating the color of the dot as it moves) such that nobody could intercept and spoof it (because nobody could do that FTL). And it doesn't require quantum tricks. You would just need some way to synchronize the emitter and detector so that the detector is in phase in terms of when it expects the next transmission to arrive.
I once dealt with a patent from nuclear physicists that used the propagation in the change of polarity along a wavefront (magnetic wavefront?) for an unspoofable communications channel to military aircraft. They got the idea when researching earthquake wavefront propagation on neutron stars, IIRC. They had actually built a physical device to simulate the wavefront, and they figured out it was actually useful for something!
This could be trivially demonstrated at home by moving a water drip over clean and dry surface: the faster you move the less water end on the surface and the further away drops are spaced.
Then do it with a stream of water... and you can still move it faster than the speed of waves in the water. Doesn't matter if you were in a regime where you can treat light as waves or photons, it still allows you to move an illuminated point faster than light. This is no different than carefully timing a bunch of pulses on marque lights so they appear to move faster than light. In neither case is information moving faster than light because you had to set things up before hand or in the case of a laser pulse you still have to wait for light to get there from the laser pointer. It has nothing to do with whether light is continuous or not.
How is that not information gained at the speed of entanglement, i.e. faster than the speed of light?
Because you gave a bad example that is not distinguishable from a hidden variable (e.g. someone just writing instructions down on paper, sending one to the distant point and handing you a copy to read later), whereas quantum mechanics allow for more complicated situations that allow for changes to be applied to the entangled pair after they separate and have both ends be impacted (although in a way that doesn't convey what changes you've applied, hence not allowing any additional information to be sent).
Relevant link: "Terrestrial and Extraterrestrial Radiation Sources that Move Faster than Light", https://repository.unm.edu/bitstream/handle/1928/22017/MS_thesis_aschmidt.pdf
what's the point of saying such in the article though?
is the article just trolling? since if the observed thing is defined like that you can "observe ftl" with a point and shoot.
world was created 5 seconds before this post as it is.
It's wonderful that your delusions include FTL being possible, but maybe you can refrain from commenting on physics articles until you actually have something passable as a physics education?
You have a moon full of photoreceptors tuned to the color of your laser. Over a short period some number of these are struck by photons from your laser. Nothing moved faster than the speed of light in order to make this happen, no matter how fast the "dot" appeared to move, and nothing can turn those individual photon strikes into a comprehensible signal faster than the speed of light.
See here. See also a fucking relativity textbook, your ignorance is really fucking annoying.
Good point, but it assumes the laser is emitting a stream of single photons. As long as you have enough photons being, it's not necessary that you perceive any skipping.
But reverse the scenario. Install a series of powerful lasers in a line along the surface of the moon. Now program them to briefly turn on such that you see _smooth_ FTL apparent motion from Earth.
Of course, "smooth" is something of a weasel word. But there exist propagation patterns that are smooth as quantum mechanics will allow. I'm not a physicist, but I believe generally they involved propagation _along_ wavefronts or some such phenomenon. And these occur in nature.
Also, as I mentioned elsewhere, FTL apparent motion can actually be applied to do cool things. It's not all just word games.
Billions of Frames per second versus trillions of cycles per second must make for quite the choppy video!
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Because they wanted to avoid the discussion of whether information could travel faster than light. Perhaps one of the researchers kept making that distinction, so the ignorant reporter repeated it without knowing what it meant.
It does at least usefully point out that though "something" is traveling faster than light, information, mass and energy can't.
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There is actually nothing which travels. Imaging you turn on lights one-by-one in a chain of lights. It would appear as if the light moves. Ofcourse this apparent movement can be made to be faster than the speed of light.
" Nothing moved faster than the speed of light in order to make this happen, no matter how fast the "dot" appeared to move"
And yet the dot can be seen to move faster than the speed of light allows, across the surface of the moon. If the receiver on the moon is looking at the laser, at some point along the laser it will see it moving faster than the speed of light.
Encode information in changes of a multiple of the speed of light. Both sides will see the dot moving faster than the speed of light, at some point along the laser beam.
What are you seeing from the earth, then? Are you seeing the laser travel across a fake moon? Where exactly is that fake image of the moon, and why can't the moon see it too from its side? From the moon side, the dot across the fake surface will also travel faster than the speed of light.
Encode information in the multiple of the speed of light that the dot (wherever it is) moves.
The apparent movement is faster than the speed of light. Nothing "travels" but something "moves".
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roman_mir reads only texts that are written by his lord and savior. i'm pretty sure he has never written a physics text, so it would be pointless to try to enroll roman_mir in a physics class.
+1 mildly amusing.
From your link:
So, you predict the wave will break at point B. But why can't you manipulate the waves so that one part is traveling faster or slower? Then your prediction is false. Encode information in how far off your prediction is.
This post, by the way, indicates that receivers on the moon will experience activation faster than the speed of light would travel between them, just as waves on the beach can break faster than the waves are traveling.
How is for example the speed of that movement not information?
Define information. I think you are confused.
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Right, the phase velocity can exceed the group velocity.
...receivers on the moon will experience activation faster than the speed of light would travel between them...
You had to change what you were talking about ("experience activation") because you're not describing a real event. Each photon travels at c from your laser, strikes a detector. The information about that strike has to be correlated with the other events, and that can happen no faster than c. Also, your prediction cannot be put to any use because the information you need to make it travels slower than the thing you're trying to predict. I'm speaking imprecisely there and it's kinda irrelevant to the point. Information cannot travel faster than c, neither can metadata. Related to this, anything that propagates at c does not experience time in any meaningful sense; it's going at the "clock rate" of the universe. If that does not make sense to you, please stop now and find a textbook.
You have an amazing ability to read an entire page of arguments and pick out only the little bits which support your preconceptions. Whenever you have an idea, and it contradicts relativity, you are wrong, and you should try to focus on understand why instead of your own idea. You are not smarter than Einstein, and more to the point, relativity has been tested to an absurd degree. We are really, really sure that however unintuitive the results are, the universe provably works that way.
the information of the light still travels at the speed of light, it simply is the point of origin is no longer able to send data wherever you point it in order for the destination dot to be shining on some parts of the clouds at a speed faster than light. so only non information of the point of reflection no longer is a solid continuous beam as light from the laser still travels at the speed of light, meaning if you were modulating data through the laser by making the arc points technically too far apart for the speed of light to reflect along the whole ark it looks a lot like image stutter.
In the classic case where Alice and Bob each have one photon of a previously-entangled pair, once Alice measures her photon, she knows what Bob will see. If there is a deterministic process in place that Bob follows upon measuring his photon, Alice now knows what Bob will do. She can prepare accordingly. She has gained information by measuring her photon; she knows what the other measurement will be. In the scenario mentioned, she knows what will happen across the universe, faster than she could otherwise know if she were limited to learning about what the other side saw, by the speed of light.
You can't modulate the signal (force the next particle to be either spin up or spin down), so what propagates faster than the speed of light is random noise (no information). You cannot be deliberate about what information to send.
I'm going to make a distinction that is I think very subtle. So I could easily screw it up.
The 'dot' doesn't actually move. Light from the laser is striking the moon at a certain point.
You are seeing reflected laser light from that point. Assuming you can see it of course.
When you flick your wrist at a speed of 1/100th of a second the target for the laser moves across the moon
in 1/100th of a second. The target changed its position at a rate faster than the speed of light. Only the target.
Laser light traveling from the earth to the moon will still travel at the speed of light and photons will still take time to hit your target. Will still travel only at the speed of light and the photons striking the moon at the different target locations are not traveling faster than the speed of light.
In an idealized world, the laser would rotate at a smooth continuous arc and we would have a smooth continuous dot across the surface of the moon, meaning the photons leaving the laser would need to leave it at a speed faster than the speed of light to maintain a truly continuous trail of light across the moon. Otherwise there would be jumps in the point across the surface of the moon as the photons at source could not keep up.
I think there would be jumps. We can't observe any of this anyways from the earth. We would need an imaging device tracing photon movement across the moon at the size of a photon and at the speed of light. We don't have anything to do the measurement.
So I think its only the appearance of faster than light behavior and that actually there would be gaps between points on the moon but we could not see them. How could we?
Very simply: this is not communication, but a deduction made simultaneously by two parties working on the same premises. You could replace the entangled particle with two sealed envelopes containing the same (as yet unexamined) information and it would be identical. Hell, take it one step further: the information in the sealed envelopes could just be a description of the state of some particle you chose at random.
It isn't faster-than-light communication so much as it is guaranteed shared knowledge -- you and the computer both make the same deduction from information regarding the particle, and you both have access to information regarding the particle. But there's no way for you or the computer to influence (or even attempt to influence) the other. Further, it's not certain: the computer could have been dismantled or had its programming changed or had its local star go supernova and you wouldn't know, in which case your deduction of the computer's attack would be incorrect -- by contrast, if the computer were communicating with you instantaneously, you *would* know these things (or at the very least would know the computer didn't communicate with you for some reason).
I would say there is nothing which moves - atleast nothing physical. There are *different* things happening synchronized in a way that there is the appearance of motion. But talking about "motion" depends on an observer who synthesizes these different events into a motion of a single logical object. Similar to how a mouse pointer moves on a screen. Nothing actually moves. This is simply an illusion, not "propagation of non-information".
What sensor do we have that could detect the change in the position of the dot that actually worked faster than the speed of light? It's impossible for us to build such a sensor.
If it can watch photons move, what exactly transfers the existence of those photons to the camera's sensor? some of the photons that refract from dust and air?
All those moments will be lost in time, like tears in rain... time... to... die...
Sounds like you could replace the entangled particles with a pseudo-random number generator and get the same result.
You can't say for sure that the other party acted on the result of the particle/PRNG though. You can predict with a high degree of accuracy, but something could have changed (maybe the power went out, or the other side decided to change what happens when it reads a 1).
I don't think they will. The first receiver will activate when a photon strikes it. Then the target has moved to another location faster than the speed of light. However the laser photons travel in a straight line and don't bend when you rotate the laser. The photon that strikes the receptor at a faster than light distance will still take the speed of light to travel from the laser on the earth to the target. So the next receptor will not fire until the appropriate speed of light time has passed for a photon to travel from the earth to the moon.
Prior photons that were on target for the original receiver will still continue to hit it. It's only new photons aimed at the new target that will hit that receiver. These photons will travel at the speed of light.
Well, if it isn't roman_mir, the guy who tries to trick people into reading his nonsense journal entries via URL-shorteners.
http://tinyurl.com/bylguza = http://slashdot.org/journal/30...
Il n'y a pas de Planet B.
Sending the information back to yourself? It will still take longer for any change of state (position on the Moon) to get back to you than it would for you to send the same information directly to yourself over vanishingly small distances...
Any change in the angle of the beam still propagates from Earth to the Moon at the speed of light. You could encode information in how fast it tilts up and down, and all you would need to receive it is a single pixel anyway, as that would just amount to a pulse-length encoding, making the speed of the dot irrelevant. If you wanted to measure it for some reason using multiple pixels, if the dot moved from one to the other faster than speed of light, then whatever system connects the two pixels together would have to wait for its internal signal to get from one pixel to the other (or to some third point). That wouldn't involve information moving faster than light though, just would be an awkward encoding method on a beam of light still moving at c from source to destination.
Actually, there's really no need to italicize the word appear, I guess.
Did you mean "underlined", which is how leading and trailing underscores are usually interpreted?
Or perhaps you meant "/appeared/" rather than "_appeared_".
In any event, now I'm done nitpicking, thanks for making it clear why nothing actually travels faster than light in the scenario you describe.
And as said, that is a really bad example, and just explaining it again doesn't change that. The situation you describe could be completely duplicated by classical systems. If you just used a laser or radio to transmit instructions to Alice and Bob in different places, you would get the exact same effect: Alice knows what Bob will do when she gets the signal, even if it will be a while before the signal gets to Bob. As said before, it could even be done with sheets of paper giving written instructions to Alice and Bob. Since entangled pairs can't be distributed faster than the speed of light, it is irrelevant that other methods spread information at or slower than the speed of light too in that example. This basic example of entanglement is almost pathological in terms of the improper view it gives of entanglement.
If you want a more complicated example that can't be reproduced classically, you need to involve something with superimposed states or something like polarization that allows different measurements to be taken of the same system, which can then be chosen after the entangled pair has been separated and can't be reproduced classically (without some sort of super-determinism at least). Instead of having something no different than stuffing two pieces of paper into a sealed envelopes, you end up with a situation more like magical dice that maintain a correlation even if they are re-rolled once in a special way.
to capture a politician being honest.
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
Actually, no. The point of light in the cloud will not move faster than the speed of light, as this violates the special relativity theory.
Please remember that pointing a laser beam onto a cloud is like transmitting information. For example, by turning the beam on and off ala morse code, a message is transmitted. So it cannot be faster than light.
" Nothing moved faster than the speed of light in order to make this happen, no matter how fast the "dot" appeared to move"
And yet the dot can be seen to move faster than the speed of light allows, across the surface of the moon. If the receiver on the moon is looking at the laser, at some point along the laser it will see it moving faster than the speed of light.
Encode information in changes of a multiple of the speed of light. Both sides will see the dot moving faster than the speed of light, at some point along the laser beam.
That is merely the viewers lack of understanding that it is not a single dot moving, It is actually a serious of reflections, each completely separate with Zero movement except along the path to and from the moon. You may as well point the laser and one spot, turn it off and point it at a spot on a billion miles away and say, look I invented warp speed. The dot hasn't moved, it is a different dot.
The point of light on the cloud (or moon) will move faster than the speed of light, but it isn't information, mass or energy that's moving, so it doesn't violate any relativity.
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The illusion moves faster than the speed of light then. And it's not an "illusion". It's real. It's tangible. It's measurable. And it can be viewed from different frames of reference.
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Alice now knows what Bob will do.
No, she only knows what Bob has agreed to do, because she agreed it with him while they were in causal contact. This is not the same as knowledge of what Bob will do. For all Alice knows, Bob could have had a heart attack last night, or his equipment could be faulty, or he might just decide to be contrary and not do what's been agreed just to prove to Alice that no information has actually exceeded the speed of light.
You're confusing the common-place meaning of "know" (as in, "I know my husband is working late at the office") with the very strict information theory version. I "know" that Alpha Centauri hasn't exploded up to this moment, but I won't know it until the light gets here in four years' time.
systemd is Roko's Basilisk.
WOW, that`s going to make for some high quality porn.
The light of a laser at large distances is actually more like a water hose spraying water. If you rotate the water hose, the water stream won't remain straight. The furthest water particles will not magically move in the direction you are rotating the hose. The furthest photons will not move with the rotation of your laser pointer.
I've tried, but I can't actually work out what you're disputing in Uecker's comments.
It's real. It's tangible. It's measurable.
What is? What's measurable about whatever it is?
systemd is Roko's Basilisk.
A camera that can catch a woman with her mouth closed.
you must be a terribly unhappy person if this rather esoteric ignorance is really fucking annoying.
aka roman_mir, the guy who believes that through the power of sheer repetition he can convert every slashdot user into another monk in his religious order.
It is said that "a picture is worth a thousand words".
How much does 100 billion pictures worth ?
There are two things we need to consider here: First: The transmission of information from earth to the moon. This is possible. But that information travels at the speed of light so it's ok. Second: The transmission of information along the dots trajectory. If you move the laser point from one crater to the next, there has been no information transfer from the first crater to the next crater. Since the dot has moved faster than light from the first crater to the second crater, BUT has not transfered information from the first crater to the second, this is ok too.
Obligatory Vsauce: https://www.youtube.com/watch?...
Vsauce explains the scissors example in this video: https://www.youtube.com/watch?...
You can, but you're sending information from yourself to the moon. If there are two communication stations and you flick your dot between them, they can't communicate with each other using the dot.
Can you be Even More Awesome?!
Ummm, if memory serves me well, isn't 1 trillion > 100 billion? Because there is already a trillion frames per second camera produced by Ramesh Raskar's team at the MIT Media Lab.... in 2011. In August of 2014, a 4.4 trillion frame per second camera was built by Keisuke Goda's very large team at the University of Tokyo. So, is Washington University in St. Louis already behind the times or are they suffering from a case of "not invented here" ?
Kudos to them for being able to pull it off at all, but it has been done already and by orders of magnitude better.
Captcha: brighter
My favourite explanation uses shadows. Imagine a wall with a spotlight shining on it. A ball is thrown parallel to the wall, half way between the wall and the spotlight. The shadow that the ball casts on the wall moves faster than the ball due to parallax. If the ball were travelling close to the speed of light, the shadow would be moving faster than the speed of light.
Of course, a shadow is actually a lack of light. It has no mass, no energy, it isn't information, so the speed of light limit does not apply to it.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Someone else linked to a YouTube of a guy talking about shadows. I think they use shadows because, though the trailing edge of the shadow is "light" and moves faster than the speed of light with the shadow, people don't object to shadows moving fast because they understand a shadow has no mass, no energy, and no information. Everything true about the shadow is true about the "light" at the edge of the shadow (both leading and trailing).
But the light isn't moving, just the event horizon.
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He claims that a moving non-object (a shadow, a reflection of light, or a mouse cursor) isn't real. They are real. They can be seen, they can be measured and defined. And they can move faster than the speed of light.
If you can't understand what I'm disputing in his comments, read my comments he replied to and tell me what he's disputing. If that's confusing, go up a few levels to my original comment, and his original objection, and tell me what he's objecting to in that one.
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https://www.google.com.bd/search?q=extrabazar.com&ie=utf-8&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&gws_rd=cr,ssl&ei=O3-AVLS0IouBuwSJhICQBg
Sure, but you're only getting the information in the time it took for the light reflecting off the cloud to reach your eye, and that light was traveling at the speed of light (in medium). So you observed something traveling faster than light, but you only got the information at a speed slower than or equal to light.
We don't have a state-run media we have a media-run state.
And the information about whether the beam was on or off will propagate at light speed.
We don't have a state-run media we have a media-run state.
That fact that you can acknowledge it, identify it, and comment on it does make it information. There is definitely information there that is traveling faster than light. For instance, if you could monitor every single atom on the moon you would notice that a particular "line" of atoms sequentially emitted photons in a pattern that propagates faster than light. The catch is that you can't receive or interpret that information FTL. I think what you mean to say is that information from the light source itself cannot propagate FTL, violating relativity.
Yes exactly, but the information itself still exists and propagates FTL. Any state, pattern or feature of the universe is information. It's just that we're limited by the speed of light as to what we can detect.
Because information you encode in such a way travels with the beam, and not with the perceived dot. You can make the dot itself move very fast, but not instantaneously. Your wrist movement will appear on the moon about 1.5s after you did it, and you yourself will observe it ~3s after.
You will receive information at a huge data rate, but the time that information burst takes to reach you is still such that it propagated at less than the speed of light.
For this you have to take into account the producer and the receptor of information. If you want to transmit information to someone on the moon, you have to factor in the time it take for the laser beam to reach the moon, bounce off the surface, and reach the observer. That still takes enough time that it propagates at less than C.
Basically, the only thing moving FTL is location of the boundary between laser-lit and not-laser-lit, it's not information in on itself, since the information of the boundary condition itself took 1.5s to reach your eyes, so it's propagating at C.
I was hoping anyone who felt informed enough to discuss the point would be informed enough to know the definition of "information".
The catch is that you can't receive or interpret that information FTL. I think what you mean to say is that information from the light source itself cannot propagate FTL, violating relativity.
Obviously. The "thing" that conveys information may travel faster than the speed of light, but the information itself can not propagate faster than the speed of light. And it doesn't.
All that is consistent with everything I've said. You are objecting that someone who is deliberately trying to argue the point can find holes where I assumed basic knowledge of relativity. I can't disagree with that. But I do disagree that your clarification in any way contradicts anything I said.
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No information in that setup propagates faster than FTL, it all propagates at the speed of light, just from a third point. If you are 100 km west of a radio tower and your friend is 100 km east of radio tower, you both get the radio transmissions from the tower at the same time (assuming no one is moving at relativistic speeds...), but that doesn't mean information instantaneously propagated over 200 km.
The example with the moon is pretty similar, and in fact you don't even have to tilt anything. If you just had a strong, pulsed, omnidirectional source, and a sensitive camera, you would see rings spread out from the closest point on the moon as the light pulse reached the edges that are further from the transmitter.
Other things can travel faster than light relative to each other, from your view point, but nothing can travel faster than light relative to you.
An obvious example, aim 2 torches at each other. From your viewpoint, the light approaches the light of the other torch at 2x light speed. There are many examples like that, and they don't break relativity.
Dumb question...isn't the speed that the light gets from the earth to the moon limited by...the speed of light? So, the light leaves your pointer, hits the moon, and comes back and hits the mirror. What's moving faster than the speed of light? I'm confused.
Ok, I try again.
He claims that a moving non-object (a shadow, a reflection of light, or a mouse cursor) isn't real. They are real.
Of course the reflections are real. The movement is not real.
They can be seen, they can be measured and defined. And they can move faster than the speed of light.
They are real, but the movement is not. There is no movement of anything - because the reflections you see at different times are different reflections. They are just synchronized in some way to make it appear as there were moving - in other words: it is an illusion. Different things appearing at different places at different times is not movement. Do you know the story of the Hare and the Hedgehog?
Then "an illusion" is "a thing". With that definition, everything I've said is 100% correct. You are just arguing over the definition of "thing". And most people would assert that one single continuous beam of light is not a collection of (near) infinite different things. There is no "trick" It is not The Prestige (or the Hare and the Hedgehog) where a body double makes a trick where non-movement gets a different thing to the other place first. The single shadow/beam passes over all points on the way to the other side, and is indistinguishable from the initial one because it is the initial one.
The event moves faster than the speed of light, but violates no rules of relativity.
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