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Temporal Cloak Erases Data From History

Soulskill posted about a year ago | from the incognito-mode-on-steroids dept.

Communications 102

ananyo writes "Electrical engineers have used lasers to create a cloak that can hide communications in a 'time hole', so that it seems as if they were never sent. The method is the first that can cloak data streams sent at the rapid rates typically seen in telecommunications systems. It opens the door to ultra-secure transmission schemes, and may also provide a way to better shield information from noise corruption (abstract). The researchers manipulated laser light in time to create regular periods with zero light intensity (a Talbot carpet) in which to hide data. Unfortunately, the current set up erases the data-adding event entirely from history. Though they are confident that future modifications will allow them, or others, to send secret messages successfully, the more immediate use of the technology will be to cut down crosstalk when multiple data streams share the same fibre." Also at Slash Datacenter.

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what (5, Interesting)

Ragzouken (943900) | about a year ago | (#43918447)

Maybe it's just that it's late, but I have no idea what that summary was trying to say.

Re:what (1)

Synerg1y (2169962) | about a year ago | (#43918541)

On that note, I'll believe it when I see it, why no video?

Re:what (2)

Pseudonym (62607) | about a year ago | (#43919867)

Pics or it did happen.

Re:what (2)

kaws (2589929) | about a year ago | (#43920131)

I think that's exactly the problem that they're having. They're erasing a signal from history instead of just cloaking it.

Re:what (1)

jonfr (888673) | about a year ago | (#43920403)

You can't have pictures, it didn't happen yet.

Re: (-1, Troll)

Anonymous Coward | about a year ago | (#43921049)

OK here's a pic. Here is where they show a sample of a "time hole".

http://cdn.memegenerator.net/instances/400x/34992113.jpg [memegenerator.net]

Re: (1)

Anonymous Coward | about a year ago | (#43921923)

NSFW!

Re: (-1)

Anonymous Coward | about a year ago | (#43922953)

In what way? That is one of the internet classics and you boss probably posted it on message boards to troll people in the 90's. He will laugh at you for being trolled by it and angry at you for reading slashdot in the first place.

Re:what (1)

pyalot (1197273) | about a year ago | (#43929741)

I believe the summary said that they where hiding signals by not sending any...

Re:what (5, Interesting)

sosume (680416) | about a year ago | (#43918553)

FTA: "Unfortunately, the current set up erases the data-adding event entirely from history. "
So how do they know that they sent it in the first place?

Re:what (2)

Doug Otto (2821601) | about a year ago | (#43918571)

"Trust us"

Re:what (2)

Impy the Impiuos Imp (442658) | about a year ago | (#43919465)

1. Encode data in beam.
2. Manipulate beam in funky ways so data is removed.
3. ????
4. Profit!

Re:what (2)

Garridan (597129) | about a year ago | (#43919663)

For some reason, the researchers couldn't seem to remember the answer to that question when asked.

Re:what (1)

jonfr (888673) | about a year ago | (#43920173)

If I explained to you, I am not sure if you would understand me. While I am not connected to this project that is written about in nature. I am going to try anyway, at least in the simple terms.

This is however related to time, subject that I do understand. Since I think about it a lot.

This is what I call a "D" event. A event "A" (sending the data) is created. That event exist in normal space time, the data sent "B" event is sent a long normal space time where light exist. Light travels along normal space time, a "C" event. Transmitted data gets "lost" in time, that is the "D" event. At least as I am reading this, I do lack a lot of data about what was done. So I am mostly guessing what was done. This might be something else if there is a lot of wrong information about this online (good chance that is the case).

The interesting part is that the data actually does not get "lost", it is going to appear again. Be that in the past, present or the future I have no way to know. It depends on the data x,y,z (time is at least 3 dimensional) exit location in the time "stream" (I do not have any better word for this phenomenon in regards to time it self), so the data might appear today, it might have appeared 10,000 years ago or 10 billion years in the future. I do not have any way at all to know that, so I am just going to ignore it.

This might sound like rubbish and nonsense to you. But they are loosing data by splitting light and time and creating time bubbles in the time stream already. I am however not so good with school, so I never did go up to the university level. I just never bothered to do so and I do not expect to do so any time soon. So I do not have any degrees or tools to perform stunts like this.

Instead I just do thought experiments.

Re:what (3, Informative)

TheCarp (96830) | about a year ago | (#43920623)

I never did much time in college either but, that's besides the point. I found a couple of better articles and exploitations, by people who seem to actually understand it:
http://www.technologyreview.com/view/424682/first-demonstration-of-time-cloaking/ [technologyreview.com]

So, they are speeding up some photons, and slowing others, to create a "gap", passing something through that gap, and then, readjusting speeds. So, imagine the beam is..... Route 1 in Saugus MA. One of my favorite roads. Its not just 6 lanes of bumper to bumper traffic, that traffic is bumper to bumper at full speed.

Like most beams of light, you have fuck all chance of passing through it without casting a shadow (this is the detected event being "hidden"). But imagine if all the cars were in communication by computer. A mile down the road about haldf the cars speed up, and bunch together, and the other half all slow down, then all resume normal speed, creating a traveling gap.

Now, if you knew this gap was coming, you could scurry through it without traffic detecting you across the pavement.... after which, they perform the opposite operation, sealing the gap, as if nothing happened.

Sounds like a really cool system doesn't it? Now lets imagine it has a limitation of a 100 foot gap, moving at 75 MPH, giving you less than a second to pass the 60 feet of tar before you get....detected

I think part of the reason this sounds so weird is the terminology. It makes sense, there is no point in space where an object can be continuously and not be detected by the beam, however there are points which the beam intersects in space where the object can be, between the beam, and not interfere with the final beam...

Or at least, that's what I get from it.

Re:what (1)

cstacy (534252) | about a year ago | (#43921489)

So, imagine the beam is..... Route 1 in Saugus MA. One of my favorite roads. Its not just 6 lanes of bumper to bumper traffic, that traffic is bumper to bumper at full speed.

Like most beams of light, you have fuck all chance of passing through it without casting a shadow (this is the detected event being "hidden"). But imagine if all the cars were in communication by computer. A mile down the road about haldf the cars speed up, and bunch together, and the other half all slow down, then all resume normal speed, creating a traveling gap.

I am in the car that is stopping at Kelly's!

Re:what (0)

Anonymous Coward | about a year ago | (#43930169)

Stay away from my girlfriend you rat bastard!

Re:what (0)

Anonymous Coward | about a year ago | (#43922025)

"Now, if you knew this gap was coming, you could scurry through it without traffic detecting you across the pavement..."

No, no, no, it's not "you" who crosses the road during the gap, it's "the chicken".

Don't ask why.

Re:what (0)

Anonymous Coward | about a year ago | (#43922969)

Now lets imagine it has a limitation of a 100 foot gap, moving at 75 MPH, giving you less than a second to pass the 60 feet of tar before you get....detected

Been there, done that.

Re:what (1, Flamebait)

BitZtream (692029) | about a year ago | (#43920823)

Since I think about it a lot.

Good thing thats all that is needed on slashdot to qualify you as an expert.

I am however not so good with school, so I never did go up to the university level. I just never bothered to do so and I do not expect to do so any time soon.

Right. Thats why your a genius but not in any field like this one.

Instead I just do thought experiments.

Clearly. One of those experiments seems to be thinking you have a clue.

The reality is, you don't know enough to even realize its a scam. You believe in cold fusion and perpetual motion machines as well I'm sure.

spacetime (0)

Anonymous Coward | about a year ago | (#43921449)

relativity means your full of shit....im not wasting more time then i need to you cant send something which can get bent via spacetime and thus has ot always exist and hten say it doesnt and still does.

YOU could use spooky action at a distance and entangle two particles or more and put each at your two locations and have one send on and off by change of rotations.....thus not needing any thing in between BUT we are a long way off of a real quantum bandwidth let alone a computer that can read them and create and send the other entangled particle to the other person in secure means.

and time travel into the past is not possible YOU CANT have a particle exist and have it exist before it does elsewhere....that comes under the laws that say matter and energy cannot be created ONLY change states.
YOUR pretend idea has a paradox of new matter in the universe and that is just not possible sorry...
go read up on the way talbot stuff works ....diffraction's are bending the light so it acts differently then you expect this "appears" to do spooky stuff....it simply means one needs ot crack how one does the diffraction and you have the data unsecured.

Re:what (3, Informative)

Shavano (2541114) | about a year ago | (#43920771)

Because the light pulses went into the pipe. Theoretically, if the build their modulators right and exactly undo what they did to make their "time holes" (which normal people would call dark intervals the original unmodulated light will be there on the fiber, superposed with a temporally spread version of the coded pulses they injected, which would be there, but hard to detect.

At the other end of the obscured connection, the trick is to run the same modulation scheme again exactly and if you do it just right, the monochromatic component of the light will once again be spread into the gappy modulation pattern you had at the first modulator output, and the pulses you injected will be there in the otherwise dark intervals.

The scheme depends on two things: (1) you have to time it exactly so that you don't lose the phasing between the original modulator pair and the modulator at the receiving end. If you miss the phase, your data will be in the bright intervals instead of the dark intervals and you won't be able to read it easily. That's what apparently happened in this experiment and why they're confident that what they did really happened even though they didn't get their data back out of the system. The other thing (2) it depends on is that the modulators have to be linear enough that when you modulate and remodulate the light, you don't mix the spectra of the data with the stream you're using to obscure the pulse sequence. If they mix, you won't get a clean signal out no matter how exactly you match the modulators.

The second is a likely limitation on this scheme because they are using nonlinear modulators -- all electro-optically active materials are nonlinear. Linear materials don't modulate light. To do completely linear modulation, you would need to do the modulation mechanically, which is much to slow to create the kind of quite intervals they need to obscure their data.

Re:what (1)

Shortguy881 (2883333) | about a year ago | (#43925243)

Im glad Im not the only one who read that far. By the sound of it this would be like writing a secret message on a piece of paper. Then taking that paper and mushing it back into pulp, washing it and turning it back into paper. Yes there is "hidden data," but can we ever recover it? Lets then say that they determine how to reassemble the data from that near complete destruction, once one person knows how to do it, then everyone knows and the data can be captured and hacked just like any other technology.

Re:what (0)

Anonymous Coward | about a year ago | (#43918559)

They want to put your communications in their time hole.

Re:what (1)

Bovius (1243040) | about a year ago | (#43918565)

My initial reaction to the summary: Okay, I know a lot of us in Slashdot crowd are gullible, but seriously? I demand a plausible lie.

Reaction after reading the article: I suspect that the translation from an actual technical explanation to language intended for the layman was shaky at best. I don't think I've read an adequate explanation of how it actually works.

Re:what (2)

Antipater (2053064) | about a year ago | (#43918685)

Here's [dailymail.co.uk] an explanation from the last time the media tried to report on time-cloaking. I think it came off a little more clearly.

Re:what (1)

BitZtream (692029) | about a year ago | (#43920839)

Thanks.

Posting a daily mail link just proves its rubbish.

Re:what (1)

geekoid (135745) | about a year ago | (#43918587)

Read the article. It will blow your mind.

You can creata situation where all information stay in a bubble, when ther bubble collapse it's as if the informatiomnn had never exsited.

So if normal destruciton of information was like burning a paper, even the informatiojn is still there, in the ash. Hard to get, but still it is there.

This would be like being able to create a paper, use it, and then have it never have exisited.

Re:what (1)

mark-t (151149) | about a year ago | (#43918965)

If it never existed, how could there be any memory of its use?

Re:what (1)

geekoid (135745) | about a year ago | (#43919045)

Becasue the informtion is in it's own bubble of time.
Also, time doesn't seem to work they way we precieve it. So anything dealing with time intuitivly feels wrong.

It could be that the effect is no good becasue there is no way to retrieve it. If not, well. All kinds of wierd things become possible.

In my very limited example the person who wrote the info ont he paper, and the person who read it would still remember the information.

Time locked (0)

Anonymous Coward | about a year ago | (#43919183)

It would be time locked, only a Dalek could escape and it would induce madness!

Re:what (1)

mark-t (151149) | about a year ago | (#43919283)

If something never happened, then there can't be any record of it.... that would *INCLUDE* human memory. To erase all record of something having existed would also entail erasing all human memory of its existence as well.

Re: what (0)

Anonymous Coward | about a year ago | (#43919729)

There's a crack in my wall.

Re:what (1)

game kid (805301) | about a year ago | (#43919397)

In the wake of this news, millions of teenagers anticipate a new version of Snapchat.

Re:what (1)

K. S. Kyosuke (729550) | about a year ago | (#43918855)

Maybe it's just that it's late, but I have no idea what that summary was trying to say.

It's quite obvious, isn't it? Let me quote it again:

The researchers manipulated laser light in time to create regular periods with zero light intensity (a Talbot carpet) in which to hide data.

Basically, they're saying that even in our 21th century, the fabulous Age of Lasers (on Sharks), sweeping inconvenient stuff under the rug is still alive and well.

Re:what (1)

geekoid (135745) | about a year ago | (#43919053)

What is alive and well is people who don't understand things so they use an logical fallacy to dismiss it. Yes, I am looking at you.

Re:what (1)

BitZtream (692029) | about a year ago | (#43920855)

Look, this isn't hard.

If something is erased from history, then you can not have knowledge of it. Its a paradox. If you have no knowledge of it, you can't even know its missing, nor could you have sent it in the first place.

Common sense trumps sensationalist articles claiming to have accomplished something that contradicts itself.

Re:what (1)

narcc (412956) | about a year ago | (#43921111)

What is alive and well is people who don't understand things so they use an logical fallacy to dismiss it. Yes, I am looking at you.

You should probably look up the term "logical fallacy".

Re:what (1)

K. S. Kyosuke (729550) | about a year ago | (#43921147)

I think you misspelled the word "pun".

Re: what (0)

Anonymous Coward | about a year ago | (#43919237)

I think what they mean is controlled periods, not regular periods, where the absence of light conveys information.

Re:what (2)

CaseyJParker (2853813) | about a year ago | (#43919287)

Um ... time travel? :\

Re:what (2)

Em Adespoton (792954) | about a year ago | (#43919321)

Maybe it's just that it's late, but I have no idea what that summary was trying to say.

When this article was posted yesterday, you understood it completely. Unfortunately, I can't seem to find the uri anymore to prove it to you....

Re:what (1)

Anonymous Coward | about a year ago | (#43919523)

Whatever you do, don't cross the streams!

Re:what (1)

Shavano (2541114) | about a year ago | (#43920679)

Take this into consideration, according to the quoted article:

"Their work built on the principles behind invisibility cloaks, which hide objects in space by channelling light rays around them."

... or would if they could actually do that.

Re:what (1)

BitZtream (692029) | about a year ago | (#43920863)

Invisibility cloaks exist that do exactly that. Do you live in a box? They aren't even new anymore. They also are currently so narrow band that they are pretty useless practically, but its got to start somewhere.

and neither does poster (0)

Anonymous Coward | about a year ago | (#43921407)

ive read up on his talbot diffraction stuff and ya know what i can give you a proof to show that it can be uncloaked as well as he says cloaked , it is just not something that i will find cheaply nor easy to do.
Fact is thi sis just a nifty form of obscurity that's just a bit more hard to grasp and expensive enough to crack. YES crack. but hey nice try boys keep on trying...the noise reduction bit might make who ever is watching go ...hrm thats not normal run the anti diffraction routines through that giant arse super computer see if we get anomalies that would warrant further scrutiny....YUP in 5 minutes i got the angle....so will THEY..whoever they are.

Re:what (0)

Anonymous Coward | about a year ago | (#43921419)

It's not that it's late.

It's that the relevant information has been erased from the summary by this new technology. Duh!

Re:what (0)

Anonymous Coward | about a year ago | (#43922029)

They demonstrated their technology. They told you, and then used the temporal cloak to undo it.

Erasing from history? (3, Funny)

Anonymous Coward | about a year ago | (#43918513)

Isn't that what happens when you touch the crack in the universe caused by an exploding Tardis?

errr... (2)

Arancaytar (966377) | about a year ago | (#43918549)

How does the recipient get the message, if it's so thoroughly erased?

Re:errr... (1)

drkim (1559875) | about a year ago | (#43918959)

How does the recipient get the message, if it's so thoroughly erased?

Ahhh... what message?

Re:errr... (1)

mark-t (151149) | about a year ago | (#43918985)

Even more, how does the sender know that they even sent it in the first place?

Re:errr... (0)

Anonymous Coward | about a year ago | (#43919005)

They don't. As TFA says, "Unfortunately, the current set-up may be a little too good at hiding things. 'We erased the data-adding event entirely from history, so there’s no way that data could be sent as a useful message to anyone, even a genuine recipient'..."

Re:errr... (0)

Anonymous Coward | about a year ago | (#43919031)

Yep, as the headline says, its currently useless, but maybe that could be fixed. I don't know why a title was selected that only mentions the defect, not the potential use, or that the defect is not the point. As it is, its just a fancy way to accomplish nothing, only the details are interesting.

And so it begins (1)

Anonymous Coward | about a year ago | (#43918573)

I shall now hibernate until I can hop on a spaceship and mine asteroids.

"Erased from history"? (3, Interesting)

Millennium (2451) | about a year ago | (#43918611)

Does this mean they've proven the past is mutable?

Re:"Erased from history"? (4, Funny)

Black Parrot (19622) | about a year ago | (#43918645)

The funny part is that this technology has already been invented multiple times... they just keep erasing it.

Re:"Erased from history"? (1)

SnarfQuest (469614) | about a year ago | (#43918905)

This article used to be a DUP.

Re:"Erased from history"? (0)

Anonymous Coward | about a year ago | (#43923539)

I can't get my head around this, can someone explain it in simple terms? I think I read TFA, but I can't really remember...

Re:"Erased from history"? (1)

BitZtream (692029) | about a year ago | (#43921337)

No, because it has nothing to do with actually changing the past.

Its just a modulation technique. Its actually almost identical to the same modulation a cable modem or cell phone uses.

Its not a 'temporal cloak' its just a different form of modulation. The data is detectable by anyone who knows what modulation you're using and the timing for it. It doesn't get 'erased', its just not easily visible unless you happen to know what you're looking for ... exactly like hooking a volt meter up to your cable wall jack isn't going to yield any sort of useful result because your meter isn't designed to demodulate the cable signal. Doesn't mean the signals not there, as the instant you hook a cable modem up, it'll go to town and link up with the router on the other end.

Lookup QAM ... thats more or less ALL this is.

Re:"Erased from history"? (1)

siddesu (698447) | about a year ago | (#43926785)

No, they just found a better way to send stuff to the NSA for analysis.

Breakthrough? (0)

sgrover (1167171) | about a year ago | (#43918617)

So, if a laser is used to send pulses of light that represents data, and they have developed a method to create "periods of zero light intensity" that hides data and *may* help prevent noise corruption... Does that mean they have figured out how to turn the laser off? Maybe I should go RTFA...

Re:Breakthrough? (0)

Anonymous Coward | about a year ago | (#43919217)

Of course not, they obviously made a black light filter.

Now I can finally block the sunlight out by turning on my blacklight torch so I can actually see my damn monitor!

Uhm... (1)

Black Parrot (19622) | about a year ago | (#43918623)

If they erase it from history, doesn't that mean the recipient forgets it too?

Re:Uhm... (2)

Intropy (2009018) | about a year ago | (#43918657)

Yes. And I used to have already had told you that, but now I haven't yet not failed to have told you. That's why you now no longer know. You've now never known!

Re:Uhm... (1)

Anonymous Coward | about a year ago | (#43919889)

So If they erase it from history, doesn't that mean the recipient forgets it too?

Re:Uhm... (1)

oldhack (1037484) | about a year ago | (#43920245)

This is why we should never fuck with time - just not worth all the hassle that crop up.

Re:Uhm... (1)

narcc (412956) | about a year ago | (#43921169)

That's why I keep the bedside clock plugged in to a UPS.

And so it begins... (0)

Anonymous Coward | about a year ago | (#43918705)

Muuhahahahahahahaaa...

That's what I keep telling my credit card company! (0)

Anonymous Coward | about a year ago | (#43918831)

And they still don't believe I send my payment. :-(

You "can" escape your past (0)

Anonymous Coward | about a year ago | (#43918853)

Facebook has known about this for years, but they've been quietly erasing all history of its knowledge. It's just plain bad for business.

Already have time-shifting messages ... (0)

Anonymous Coward | about a year ago | (#43918893)

Ever notice how it takes cheques six to ten weeks to arrive in the mail, but bills arrive the day they were sent (sometimes sooner)?

So eavesdrop at the endpoints? (1)

nielsm (1616577) | about a year ago | (#43918971)

Without having really understood the physics behind this, what I gather is that it basically would allow you to conceal optical signals from eavesdropping on the transmission line. But that's only on the transmission line. Obviously the transmitted data still needs to exist at the endpoints in one form or another... so eavesdrop on the endpoints instead? Unless you have a true point-to-point line, your data will also likely be routed over some sort of IP network, where it will have to exist in some other form for at least short periods of time.

Re:So eavesdrop at the endpoints? (1)

geekoid (135745) | about a year ago | (#43919153)

Imagine celll phones. Now no one in the middle would even know that information had been sent.
Sure, you can watch the person with the phone and use a camera to see the text. But with glovbal communication, thats not the largest problem.

Re:So eavesdrop at the endpoints? (1)

BitZtream (692029) | about a year ago | (#43920867)

If I can't see it, neither can the receiver.

Its either detectable or it isn't. If it isn't, no one can see it. If it is, then I can see it too.

Proof that it works (4, Funny)

camperdave (969942) | about a year ago | (#43918981)

Here's proof that it works. I used it to cloak my First Post. Go ahead and check. You won't see it there.

Re:Proof that it works (1)

geekoid (135745) | about a year ago | (#43919109)

Are you sayng Henery Phillips created the Phillips screw, but couldn't figure out how to use it?
Personally I perfer the Fearson to the Phillips.

Re:Proof that it works (1)

camperdave (969942) | about a year ago | (#43920991)

Are you sayng Henery Phillips created the Phillips screw, but couldn't figure out how to use it?.

No. Thompson invented it, but couldn't get anyone to manufacture it. He sold the patents to his buddy Phillips, who made improvements to the design which made it easier to manufacture. Then he set up a company to actually manufacture them.

No, really... (1)

naoursla (99850) | about a year ago | (#43919009)

Is this just some researchers turning off a laser?

Turning off a laser so that it appears to stay on (1, Informative)

raymorris (2726007) | about a year ago | (#43920163)

Yep, all that mumbo jumbo about time cloaks comes down to this:

They found a way to turn a laser on and off really fast, and at the other end of the fiber undo it so it appears to have stayed on. The whole "cloak" thing is just the idea that while the laser is off, some other signal could be sent on the fiber. Yay, with more refinement they can use it to send two channels on one fiber. The current implementation isn't able to read the second channel.

In theory, you could cut into a backbone provider's fiber and insert one of these transmitters that adds a second channel. At the other end of the fiber, you could insert the "undo" unit, so the owner of the fiber couldn't see your signal. You'd be using their fiber without their knowledge. Of course, a fiber equipped router at each end would achieve the same result.

Re:Turning off a laser so that it appears to stay (0)

Anonymous Coward | about a year ago | (#43920293)

So, it's just boring old multiplexing and not unraveling the fabric of the universe? I'm kind of disappointed, to be honest.

Re:Turning off a laser so that it appears to stay (1)

mcmonkey (96054) | about a year ago | (#43927461)

So, it's just boring old multiplexing and not unraveling the fabric of the universe? I'm kind of disappointed, to be honest.

Just wait til Hedley lemarr hears about this!

Re: Turning off a laser so that it appears to stay (0)

Anonymous Coward | about a year ago | (#43920549)

actually that is not what they are doing at all, esssentially what they are doing is creating temporal holes, in which regardless of what data they add into the laser transmission, it doesnt leave the hole, itms effectively locked into the temporal hole that was created. the effect basically creates periods in which the optical transmission is completely immune from any alteration or degradation. this is not the same as pulsing the optical beam, this is something entirely and completely different.

lol (0)

Anonymous Coward | about a year ago | (#43921515)

go back to youtube ok buddy...no really at least your amusing for a minute.
YOU CANT create new matter in the universe especially into a space that may already contain atoms like air or other particles the risk might mean a nuclear explosion .....ya know two things trying to occupy the same space BOOOOOOOM....but hey nice fiction writer you'd make

Re: Turning off a laser so that it appears to stay (0)

Anonymous Coward | about a year ago | (#43925507)

How do they avoid getting stuck in a time loop? Or worse, how do they prevent a cascade feedback loop that converts all matter and energy in the future into these hidden signals? Do you think this can be combined with entangle particles across time to realize my dream of quantum based fusion?

So can I erase yesterday's spam? (1)

mysidia (191772) | about a year ago | (#43919449)

Now that the spammers have finally been identified... is it possible to integrate the temporal cloak with a retroactive spam filtering device, to erase my spam in the past before the filters were able to detect it, so I will not have wasted time reading it?

Re:So can I erase yesterday's spam? (1)

Daetrin (576516) | about a year ago | (#43920333)

It's already been done! The new spam cloaker is 90% effective at removing spam from history! You're now receiving one tenth the spam you were before! Unfortunately since the rest was erased from history you just don't remember how much spam you were actually getting before the machine was turned on, but believe us there was quite a lot of it! You may _think_ you're getting a lot now, but that's really practically nothing!

You're welcome!

Re:So can I erase yesterday's spam? (1)

mysidia (191772) | about a year ago | (#43920365)

It's already been done! The new spam cloaker is 90% effective at removing spam from history!

Thank you... unfortunately, this 10% that got left over is a big PITA.

Is there any way we can erase the spammers from history too -- as in erase their genetic material from being communicated during conception, so that the spammers were never born in the first place, or would that be too dangerous?

and you can create matter (0)

Anonymous Coward | about a year ago | (#43921811)

WOW neat wodnfer why this hasn't made headline news that they can create new photons of matter this shine a trillion beams a light into the past and reorder then into a trillion in gold...ya can't wait for the news.

send me the pizza i ordered 40 minutes from now right now will ya

WE have a printer like this.... (1)

Lumpy (12016) | about a year ago | (#43919553)

The output of the top secret printer feeds into a cross cut shredder and that dumps directly into the incinerator furnace. It is used all the time for extremely high sensitivity documents.

First Post (1)

EGenius007 (1125395) | about a year ago | (#43919629)

Sure, it might not look like it now, but that's only because I haven't activated my lasers.

reinventing color tv (5, Interesting)

slew (2918) | about a year ago | (#43919797)

As far as I can tell, they are mostly just doing a twist on something that was known a long time ago: quadrature modulation.

The way color TV transmission worked in the past (not anymore, it's all digital now, but I digress) was that they crammed 3 signals in the space original meant for black-and-white TV by basically converting RGB into Y (an approximation of the Black and White signal), and two color difference signals. These color difference signals were modulated to a high alternating frequency pattern (so that old B & W sets wouldn't see them very much) and then put into quadrature with each other (each signal getting about 1/2 the spatial frequency bandwidth, and essentially interleaving them in time). In some sense in quadrature modulation, you are hiding one signal in the "nulls" you create in the other signal.

In this so-called "cloak" technique, the modulation is more complex and instead of trying to transmit two equal bandwidth signals together, they are exploiting the fact that their is no reason that the split has to be equal...

The below example is overly simplified single-split case, but illustrates what is going on...

Original: Signal ~ sin(wt+kx)
Phase Modulated signal with simple small split phase shift "p": Psignal ~ 0.5*sin(wt+kx+p)+0.5*sin(wt+kx-p)
And using the magic of trigonometry ... Psignal ~ sin(wt+kx)*cos(p)

If the transmitter controls the phase just right, the "cosine" modulates the original signal and creates periods of time where the amplitude is really low (not really zero except at a point), yet back to their nominal amplitude at the receiver. Since the transmitter know when these "nulls" will be, it can put in short bursts of another covert signals that looks nominally like the original signal (same base frequency), but won't really be visible at the receiver (presumably the transmitter would pick the phase parameters of this covert signal so that they were "null" at the receiver).

In practice, a single 50-50 split with complementary phase shift isn't really that great, you have to more harmonics approximate more interesting signal envelopes. Think about making a square wave out of harmonics and you can see how you might make the apparent "null" times much longer.

Thus to the outside observer it looks mostly like the original signal (same nominal frequency for symbols being transmitted since the phase shifts are small, it would just look like jitter), but the transmitter was able to finesse the transmission so that it could transmit relatively normally so that the receiver would still pick out the signal. During the "null" times, the transmitter could transmit a covert signal which isn't picked up by the normal receiver but looks like a plausible innocuous signal, so a simple cursory observation of the channel looks as if only generic transmission is going on.

We don't have to call this stuff using descriptions like temporal cloaks and erasing information from history. Except perhaps analog color tv transmission (may it RIP)

Re:reinventing color tv (0)

Anonymous Coward | about a year ago | (#43920329)

The stupid thing is, if you know this technique is being used you can theoretically decode it. In other words, this technology is useless.

Re: reinventing color tv (0)

Anonymous Coward | about a year ago | (#43920563)

no you can not thats the whole point. not even the researchers themselves could retrieve any data that they had added during the temporal holes. the beam itself was completely unaltered and therefore nothing which was added could be recovered or decoded as you say.

Re: reinventing color tv (0)

Anonymous Coward | about a year ago | (#43921555)

YES I CAN ...and this is why your going ot get fired form your job

WOW neat wodnfer why this hasn't made headline news that they can create new photons of matter this shine a trillion beams a light into the past and reorder then into a trillion in gold...ya can't wait for the news.

send me the pizza i ordered 40 minutes from now right now will ya

Re:reinventing color tv (1)

flayzernax (1060680) | about a year ago | (#43920381)

We don't have to call this stuff using descriptions like temporal cloaks and erasing information from history. Except perhaps analog color tv transmission (may it RIP)

In other words the terminology used is a bit fuzzy and eccentric and we would do better reading about signals and probably getting a ham license =)

Thanks for taking the time to explain. This is an effect I did not know about. Still don't understand fully. But at least I know its possible and a function of wave amplitude, power, and frequency.

Blissfully ignorant (1)

PopeRatzo (965947) | about a year ago | (#43920373)

I don't want to read this story. I've made up a story in my mind, based on just the headline, "Temporal Cloak Erases Data From History", and I'm 100% sure that mine is a better story than the actual one in the summary.

And boy oh boy, do I ever want a "temporal cloak".

So this is a precursor to the Krenim weapon? (1)

Semmi Zamunda (2897397) | about a year ago | (#43920463)

I mean....zappa dappa?

Primer? (1)

h8sg8s (559966) | about a year ago | (#43921085)

Make one that erases the passage of time then make a movie about it.

Great Timing! (1)

ReverendLoki (663861) | about a year ago | (#43924611)

Great timing! Now, how soon can I get this for my Verizon phone?
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