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Thread: Do you think Faster than Light travel is possible?

  1. #1 Do you think Faster than Light travel is possible? 
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    Any ideas on how it would work? Just curious. If we're going to speculate, lets have it be about something cool. I see a lot of people trying to refute relativity. The maximum speed limit of light speed is the issue I would most like to disagree with Einstein on, but it's hard to come up with a good line of reasoning to use.


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    i'm not sure if it contradicts Einstein's equations, i thought their implication was that nothing with a mass can travel AT the speed of light

    people have often taken that to mean that you can't travel faster, since under circumstances that we can envisage you would first have to travel at that speed before you can go faster - but what if you can jump the speed-of-light boundary and go straight into the FTL bit ?

    mind you, i don't know what the physical implication of imaginary numbers is though ...


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    No, I don't think it's possible.
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    Quote Originally Posted by Neutrino
    No, I don't think it's possible.
    Well, that about sums it up. Hehe. No, really. Why do you not think so? Because, isn't MarnixR correct? That relativity is purely about entities of mass? Can light travel faster than itself? Of course, I guess the topic is about some object of mass being able to travel faster than light. But, has the question ever been answered if objects of mass can travel at the speed of light?
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    try this; if something already exist and travels faster than light, how could we know it was there?
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    Yes, a couple of British scientist came out with the idea of warping space in the 50's, made popular by star trek and other tv shows, however if i remember correctly they estimated that it would take 10 times all the energy in the universe to bend one atom round onto itself.
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  8. #7 Re: Do you think Faster than Light travel is possible? 
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    Quote Originally Posted by kojax
    Any ideas on how it would work? Just curious. If we're going to speculate, lets have it be about something cool. I see a lot of people trying to refute relativity. The maximum speed limit of light speed is the issue I would most like to disagree with Einstein on, but it's hard to come up with a good line of reasoning to use.
    I think it's possible, but there either has to be a change of rules, or a change of state to make it possible.

    Depending on how you look at the nature of particles, you either have to assume that something in our understanding of how things work is wrong, or we're just not in the right spot. What I mean by that is perhaps the key to FTL travel is not trying to move particles or objects through conventional Minkowski space, but by transitioning to another plane or dimension.

    Burkhard Heim seemed to think that changing the laws effecting a particle could be done using magnetic fields to, in effect, alter the properties of gravity to allow FTL travel. Sounds good on paper, but unfortunately like all theoretical physics there's some work to be done, and the poor fella kicked the bucket before he could really flush things out.

    Of course, there's always a third approach, and that is finding some element or method that allows us to travel FTL in conventional space. Some kind of fuel or manipulation-matter we haven't experienced yet. Maybe we just need to launch Z into orbit and have some fun?
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    I think it may be...

    light is energy, right?

    Acording to Einstein's E=mc2
    Matter can be turned into energy, and energy into matter, there are in essence the same, if we found a way to turn matter in to light energy and back again with the matter in the same state as it was when started...

    it mabye possible
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    Maybe you can go faster than light if you appear to go faster than light, or you speed up the velocity of light, or have infinite energy. Those comply with Einsteins law.
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    No. I don't think faster than light travel is possible. However, I think that altering the gravity surrounding your ship would make a time dilation field that would let you travel forward in time to your location. However, as I am a newbie so to speak I really have no idea what I'm talking about.
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    Nj14 wrote :

    "I think it may be...
    light is energy, right?
    Acording to Einstein's E=mc2
    Matter can be turned into energy, and energy into matter, there are in essence the same, if we found a way to turn matter in to light energy and back again with the matter in the same state as it was when started...
    it mabye possible ."

    It may be possible if we project the light energy onto an inclinde. The projection will travel faster than the speed of light.
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    If the gravity of a star can bend light and a black hole can stop light, could extreme gravity speed light up? Could light or something traveling towards a black hole go faster than LS?
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    You have to have something lighter than light for it to be able to travel faster than light

    or a higher frequency

    Thoughts travel faster than light

    I'm afraid big bony lumpy masses we call bodies just won't do it

    You could always put yourself in a blender and then vaporise yourself into a gas perhaps some other essence emanating from the mix might be able to travel faster than light.

    Give it a try and let me know what happens
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    Quote Originally Posted by Suhail Jalbout

    It may be possible if we project the light energy onto an inclinde. The projection will travel faster than the speed of light.
    And here is where a frequently forgotten subtlety of the Special Theory of Relativity comes into play: no signal can travel faster than light.

    Now the sweep of your light cone on an incline may be considered to travel faster than light (and you can demonstrate that this is possible), but no information is contained that that cone is taking from one point to another. (Think about it - the information comes from the light source, and making changes at the source will still conduct the signal at no more than the speed of light from the source to the current position of the projection.)
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  16. #15  
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    Gravity propagates at light speed. Maybe we can play gravity and light for faster signal. Oh yeah and we have absence of signal too, which is a kind of signal.

    ... :?
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    Quote Originally Posted by sunshinewarrior
    And here is where a frequently forgotten subtlety of the Special Theory of Relativity comes into play: no signal can travel faster than light.

    Now the sweep of your light cone on an incline may be considered to travel faster than light (and you can demonstrate that this is possible), but no information is contained that that cone is taking from one point to another. (Think about it - the information comes from the light source, and making changes at the source will still conduct the signal at no more than the speed of light from the source to the current position of the projection.)
    I am quite sure the subtleties/mathematics of Relativity are way beyond me, but I did think the Theory stated that nothing could travel at the speed of light.
    (as marnixR mentioned earlier in this thread)
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  18. #17  
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    Quote Originally Posted by Halliday
    Quote Originally Posted by sunshinewarrior
    And here is where a frequently forgotten subtlety of the Special Theory of Relativity comes into play: no signal can travel faster than light.

    Now the sweep of your light cone on an incline may be considered to travel faster than light (and you can demonstrate that this is possible), but no information is contained that that cone is taking from one point to another. (Think about it - the information comes from the light source, and making changes at the source will still conduct the signal at no more than the speed of light from the source to the current position of the projection.)
    I am quite sure the subtleties/mathematics of Relativity are way beyond me, but I did think the Theory stated that nothing could travel at the speed of light.
    (as marnixR mentioned earlier in this thread)
    It is an implication of the basic axioms of the Theory that it is signals, specifically, that cannot go faster than light.

    This wikipedia article explains some of it in the notes on Causality.
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    Einstein claims that information cannot be communicated over a distance and time that would better that achieved by a light (or radio or gravitational) signal. Even "quantum entanglement" hypothesis might suggest otherwise wrt "spin coupling" between particles (spooky action at a distance) it is still unknown how to specifically use this mechanism to communicate beyond the "c" barrier.

    The common argument for imposing a limit to velocity based on "c" arises from mass increase. Given that



    it appears that as . However we may wish to consider some caveats

    1. Could the "infinity" be infinitesimally short in time?
    2. Could the associated mass infinity and energy infinity be "borrowed" from the future and replaced later?
    3. Could this c limit be seen as a quantum well and be burrowed through?
    4. Could velocity and time be represented in complex form e.g. ?

    Some particles are proposed to travel faster than c, and presumably operate in reverse time (e.g. tachyons). We may not be able to interact with them however, so perhaps it would be a good idea to find ways to do so?
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    I tend to believe that as we become more and more advanced we will come up with a way to travel, say 10 light years, in far less than 10 years AND without going faster than the speed of light. Whether by some kind of artificial worm hole or somehow jumping to where we want to go i have no idea but i believe somewhere in the universe there are some species that have worked it out and i like to think that one day we will be one of those species.
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    Quote Originally Posted by GrowlingDog
    I tend to believe that as we become more and more advanced we will come up with a way to travel, say 10 light years, in far less than 10 years AND without going faster than the speed of light. Whether by some kind of artificial worm hole or somehow jumping to where we want to go i have no idea but i believe somewhere in the universe there are some species that have worked it out and i like to think that one day we will be one of those species.
    I cannot justify what I say, in scientific terms, but I tend to agree with you. We may even be able to travel faster than light one day.
    Years ago I saw a famous theoretical physicist, on television, giving a lecture to an audience of students. Many of the students were not science specialists. At one point the lecturer was talking about the limits of science/technology. He knew far more, than the average person, about how science/technology would develop in the next 50 to 100 years but what struck me was his arrogance. He was predicting limits for science/technology far into the future-and nobody can do that!
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    sunshinewarrior wrote:

    ” (Think about it - the information comes from the light source, and making changes at the source will still conduct the signal at no more than the speed of light from the source to the current position of the projection.)”

    ” It is an implication of the basic axioms of the Theory that it is signals, specifically, that cannot go faster than light.”

    I agree with you if a) the implication of the basic axioms of the Theory that it is signals and b) the “signals” are transmitted continuously. Let me re-write my previous post as follows:

    It may be possible if we project one single pulse of light energy, transmitted at random, onto an incline. The projection of each single pulse, which is not related to the others, will travel faster than the speed of light.
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    If you wish to have more details about the subject, please refer to my recent post "E=mc2=m(c/cos0)2" in the Pseudoscience section of The Science Forum. Thank you
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    Ok, we know that light travels in a straight line and that light follows the contour of space. Thus when a heavy mass bends or a black hole twists/stretches the fabric of space, it alters the path of light. Regardless of either, light is traveling at the same speed because it is constant. That means the fabric of space is constant, stretched or not.

    Now, we know that the fabric of space is condensed by mass or aka gravity. Gravity is not an invisible energy that pulls us down toward a point. We are actually falling toward the point due to the mass of the Earth upon the fabric of space.

    We also now that the Earth condenses time, since time is part of the fabric of space. This is evident from satellites around the earth. Your GPS device on the surface will ALWAYS be off 30 feet or so. That’s because our satellites are actually in the future by a few nano seconds and they require constant updating in time to match our own time here on the surface. This is due too a less ‘condensed’ fabric of space 100,000 miles up.

    Now, the further you move toward another star system, space is stretched and not condensed, given that mass has not altered space. Thus, one would imagine it would take less time to travel between systems. But it does not, because it is all constant. Light does not care about distance or the path in which it travels. It does not need to care, it is constant, thus you will NEVER be able to travel faster than light.

    Even if you were to condense the fabric of space between two points, you will still travel the same distance, in time and at the same speed of light. It is all constant, this is because, you will have to allow that condensed space to return to its original natural state. That is why one who travels ‘faster than light’ or in condensed space will age slightly or not at all, while everyone else in natural space will age in natural time.

    The mind bender ... either way, condensed or not, its the same distance and time.

    Thus you will be young and everyone else is long gone and dead, but you will have travelled to another star system. Not fast as one would think, remember, you have to return back to natural space. That means you did travel the distance much faster in condensed space and time, but at a cost of natural space and time.

    If light hits a clock and reflects back to my eyes, light is the speed of time. Time is the very fabric of space, thus in order to travel faster than light ... we would need to be talking about worm holes, folding space, multiverse drive technologies and not an engine that can actually travel faster than the speed of light because you can not. You can only travel with light, along the distance of space, compressed or not.
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    Well, actually, it is possible to use from Einstein's solution an answer to whether or not you can travel at faster than light speeds.

    is a famous equation. However, this applies only to particles at rest. In motion this is is multiplied by the Lorentz factor which is .

    If the velocity is equal to the speed of light, that Lorentz factor equals zero. However, if the velocity is greater than the speed of light , the answer will be a negative number.

    Multiplying this by , the energy becomes a negative number.

    Our energy is now negative! Any object going faster than the speed of light must have negative energy, which is clearly impossible.
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    I read that only space can move through space faster than light.

    So it seems that first we need to determine what space is, and what sort of energy field can make space move through space.

    Then perhaps an engine can be constructed that moves space through a tube/energy field in the same way that propeller or a jet turbine moves air.

    Such an engine might create a relative "space deficit" in front of the space ship, and a "space wave" behind the space ship. This would essentially amount to a "space warp".
    eg. a warp drive that allows the space ship to move through space in a space bubble created by the warp engine.

    Such a ship could travel faster than light.
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    Quote Originally Posted by dedo
    I read that....
    I'd like to see a source for this, out of curiousity.
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    Dedo, space cannot travel faster than light, mainly because it has no way to travel.

    What we consider space is simply a measure of the three coordinates that define us, namely, length, breadth and height. Space isn't an object that can travel anywhere.

    Where did you read this?
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    Quote Originally Posted by Liongold
    Dedo, space cannot travel faster than light, mainly because it has no way to travel.
    (s)he may be thinking of inflation. Space moved faster than light then.
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    That could be so. But that only applies to sometime after the Big Bang. There's no reason to suggest space could move that fast now.
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    I was just thinking of recession velocity of objects in the outer reaches of the universe.

    I thought it was believed that these objects moved faster than light because the space itself is expanding faster than light.
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    No, no, that doesn't happen. The only thing is that it appears the universe is accelerating, for reasons unknown.
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    Quote Originally Posted by Liongold
    No, no, that doesn't happen. The only thing is that it appears the universe is accelerating, for reasons unknown.
    What he means is that the further away we look, the faster the galaxies seem to recede away from us. This is due to the additive effect of the expansion of space. The farthest galaxies near C. I don't think it is unreasonable to suspect that there are galaxies beyond the observable point where the apparent receding velocity exceeds C. The apparent receding velocity is allowed to exceed C, as it is movement with space, as opposed to movement through space.
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    Thank you, Kalster, for clarifying that for me. In that case, I must apologise; I erred in my answers.
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    If space can expand, then it should be able to contract.

    If a device could be constructed that would move/contract space, then the "engine"
    might be able to propel a space ship forward ahead of the contracted/warped space.

    The ship would always be moving with or into "expanded" space.
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    If I might, the Big Bang offers the nearest clue of how to do this; simply cause an extremely huge amount of matter to explode. The shockwave will either cause space to expand or not at all.

    Of course, where exactly would we get enough matter to do that? And how do we stop space from extending?

    One more thing: In order to space to expand, there has to be somewhere to expand to. Imagine the universe as a steadily growing sphere. Space cannot expand into itself, naturally, so this is only feasible somewhere at the edge of the universe.
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    One more thing: In order to space to expand, there has to be somewhere to expand to.
    Sorry for repeatedly correcting you :wink: , but this is not accurate either. The big bang model describes exactly that; an expansion of space where none previously existed. So one should not think of the expanding universe as a growing bubble, since this would require the existence of an outside perspective, while none exists. Rather think of it as a 3D version of the 2D surface of a very large ball. Initially you would be able to circumnavigate the ball fairly quickly, but as the ball inflates the time it takes for subsequent circumnavigations would increase. You would start your trip and, while travelling in a straight line from your perspective, you would always end up back where you started. If you were to stand in one spot, a grid of dots would apparently be moving away from you at increasingly faster speeds the farther they are from you. If the universe is small enough you might even be able to look at yourself through a very strong telescope. At the moment it looks as though our universe is more than big and old enough for this not to be possible.
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    I think I must have misexplained myself.

    What I mean was that space could extend outwards, into regions of non-space, as it were. If you take any one region of space, you can't cause it to suddenly expand if it is surrounded by space; the two entities will behave as one.

    Space cannot expand into itself; it would be like a point in a fluid suddenly expanding to grow as big as the fluid itself . I ask you, is that possible?

    The only way for space to expand is into non-space, so expanding space can only be done at the edge of the universe.
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    But our observations show otherwise. Distance is directly proportional to receding speed, which requires expansion everywhere. In the big bang model, there is no physical "edge of space" at all, as I tried to explain with the expanding ball analogy. There is also no "outside" the universe or space. Even if you were to remove all matter, gravitation and radiation from an area, space itself would remain. Removing space would be impossible, as such a region would be the ultimate and absolute definition of nothingness, i.e. it does not exist at all. So space cannot expand into nothingness.
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    Lol, perhaps whatever is outside space is pure time?

    Just joking, of course. But my analogy of a point in a fluid suddenly expanding to become as large as the fluid also holds. Space at a point cannot suddenly expand, unless space is some sort of stretchable material, which it is not. Yet you say that space at a point must expand, because there is nothing for space as a whole to expand into and so requires that space at a point expands everywhere.

    This is a logical conundrum we've driven ourselves into. Any hopes of extracting ourselves from this?
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    It seems that I've somehow switched from thinking scientifically to thinking philosphically. Hence my use of analogies and my picture of space as a fluid. Looking back at my post, I think that was made in too much haste, so I'll look again at this.

    Let's suppose space is nothing more than a three-coordinate system we use to define a point and go from there.

    Now, looking at this from this point of view, we see it is possible for the point to grow, but what about the other points in space? They would collide with each other and merge again to form... a completely flat plane.

    Looking at it this way, I'm driven to agree with you: space can expand at every point. And I think I just solved the problem as to why experimental data is now saying that the universe has begun to accelerate.

    If we consider the Big bang as merely an event in space-time, causing the points in space to fluctuate in terms of density or size, they would expand very quickly indeed, given the amount of energy they have just been given. However, they would ultimately grow to such an extent that they merge together, creating a superbubble, which is static. From this point of view, we could say that the points in space have somehow began expanding again.

    Would this strike you as scientifically accurate?
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    Assuming that space is indeed influenced by energy (as indeed general relativity says it must) and that space can be pictured like this, dedo's question remains: is it possible to influence space in such a way that it contracts?

    Howevfer, exactly why would it expand? The enormous pressure caused by the Big Bang?
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    Is a black hole an example of contracted space?
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    It seems to me that if the big bang was responsible for the acceleration of objects/galaxies in the outer universe then these galaxies would be slowing, not accelerating.

    If the acceleration toward and perhaps past light speed by galaxies at the outer reaches of the universe is caused by expanding space, there also does not appear to be any enormous source of energy in the outer galaxy that would cause the space to expand.

    Thus, when space "expands", objects can move very fast. The key is to find out what process/type of field or energy will cause space to expand or contract.

    In a black hole, light cannot escape. It seems to me that this is evidence for "contracted space". If this was just the effect of enormous gravity on light, then would not light constantly be effected at least in a small way by massive objects?

    So I wonder what process or energy source in a black hole that would cause space to contract. This seems to be the key to developing an engine that could contract/expand space.
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  45. #44  
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    Gravity is a geometric bending of space, not a contraction or expansion. So any mass, no matter how small, has a bending effect on space known as gravity, which would affect the path of a light beam depending on the degree of the bending. In a black hole, space is bent inwards towards the singularity, so light traveling inside the event horizon and in a straight line from it's own perspective, would never be able to leave it.

    If the acceleration toward and perhaps past light speed by galaxies at the outer reaches of the universe is caused by expanding space, there also does not appear to be any enormous source of energy in the outer galaxy that would cause the space to expand.
    Remember that the receding speed of distant galaxies is only an additive apparent speed. The rate of expansion of space in those regions are not any faster at the moment than they are here, as far as we can tell. Recent data suggests that the rate of expansion is accelerating. The agent behind this is a postulated and mysterious "dark energy". If we had any idea of what this dark energy actually was, we might be able to manipulate it. :?
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

    "Gullibility kills" - Carl Sagan
    "All people know the same truth. Our lives consist of how we chose to distort it." - Harry Block
    "It is the mark of an educated mind to be able to entertain a thought without accepting it." - Aristotle
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    Of course, that depends on whether or not dark energy exists.

    Dark energy is required to allow the galaxies to appear where they are today, for otherwise without the dark energy, the galaxies we see today would not be where they are. That is one point in its favour, but I personally believe that the effects of dark energy and dark matter are because of our lack of understanding of gravity; we still have not managed to gap the vast chasm between general relativity and quantum mechanics.
    In control lies inordinate freedom; in freedom lies inordinate control.
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  47. #46  
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    Thanks Kalster and Liongold:

    I think I understand recession velocity better now. One reference that seems to help each time I reread it is:

    http://arxiv.org/abs/0707.0380

    These authors argue that there is no limit to recession velocity.
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