Do you think it's possible?
Just because both the statements "slowing down the atoms" and "atomic clock" have the word "atom" in them, does not mean they are directly related.
You don't age more slowly by walking slower.
>>32 Well, okay. I need to look up how an atomic clock works.
Rephrasing my other question: are forward-timetravel factors (gravity + speed) cumulative?
>>33
gravity and speed are the same factor.
Yes, they are cumulative.
Well, it's not as simple as being "cumulative". >>34 has it, they're different sides of the same thing. The important thing is paths through space-time. Figuring out what the result will be with strong gravity and high speed is nowhere near intuitive. You pretty much have to work through the maths to figure it out.
However, in the case of something like GPS satellites orbiting the earth, speed and gravity are both low, and the effects are approximately cumulative. However, the effects also oppose each other.
http://en.wikipedia.org/wiki/Hafele-Keating_experiment has some information on this.
I see. Ok, my next question:
As one's velocity increases, one goes forward in time. The maximum speed is the speed of light, and is a known constant.
As one approaches a strong gravity field, one goes forward in time. I guess there is a maximum for a gravity field too? Is this known?
>>37
black hole?
We are always Time Traveling to the future!!
There is no maximum as such for how strong a gravity field can be. However, a strong enough gravity field can reach the point where spacetime is bent to the point that no particles can escape, even if they move at the speed of light. As a first approximation, you can think of it as a gravity field so strong that the escape velocity is higher than the speed of light (however, you will need to account for relativistic effects when considering this in practice).
As >>38 mentions, a black hole is the prime example of this.
>>40 Something I don't understand here. Light cannot escape a black hole (obviously), but light particles have no mass, which is why they can travel at the speed of light. If a particle has no mass, how come it can be trapped in a gravity well?
Because the simplistic view of gravity as masses acting on masses in the Newtonian model is incorrect.
Actually, that's not the right explanation. Even in the Newtonian model, light is affected by gravity. But it predicts a different result than relativity. Remember, gravitational acceleration is independent of mass: A heavy body falls as fast as a light one. Thus, one without mass entirely falls as fast as one with a tiny, nearly undetectable amount of mass, which in turn falls as fast as a heavy mass.
However, in relativity it turns out this is not actually the case. In relativity, all bodies follow geodesics (that is, locally straight lines in curved space) through space-time, and matter curves space-time. However, light and mass follow different paths.
This was the basis for one of the early experiments to verify relativity: http://sunearthday.nasa.gov/2006/locations/einstein.php
>>42 Is the warping of spacetime temporary?
That is, does a light ray after passing near a strong gravity like a sun (looking bended while doing so), re-take its original trajectory?
In other words, is it just an optical illusion?
Simply put, no.
Optical illusions are created either by the brain misinterpreting information or light passing through a medium like water or air which distorts the image. Neither is happening here.
The Sun's gravity field is actually not all that strong, but it is the strongest we have nearby. And no, it's not temporary - spacetime is warped by the presence of mass. Light moves along straight lines in spacetime. After passing close to a large mass, the direction of the light will have changed.
Ok, I think I get it.
So, near a strong gravity field spacetime is warped, and that includes whatever light ray that passes thru it. Also, time is passing faster.
What if the strong gravity field is inverted? In a mathematical model of an inverted gravity field, is the time factor also inverted?
Time passing faster is not a separate effect. Also, time can pass slower or faster, depending.
Think of it like this: Two people go from point A to point B. one of the passes through an area of warped space-time, and the other does not. When they meet up, they find that less (or more) time has passed for one of them. It is not because "time has moved faster" for one, it is because their paths through spacetime were different.
Also, there are mathematical models for crazy stuff like negative masses creating weird spacetime distortions, but I don't really know anything about them so I will not comment on that.
OK.
Has there been any known instance of black holes vanishing?
Or black holes appearing where there were none before?
blech, you're starting to ask questions that are beyond me. Basically I can answer that stellar phenomenon like the creation of black holes, is not something that occurs in any amount of time we as humans can witness. It basically takes eons to mash stars together or cause them to explode thus creating black holes. I remember reading a short paper by Stephen Hawking that explained that there's a subatomic particle which is created spontaneously in space. If one were to be created on the edge of a black hole (the event horizon) part would spiral back into the black hole while half would break away and return to normal space. This is the only way a black hole can reduce it's mass, eventually decaying over countless millenia. It's been years since I read that article so the science behind it is beyond me now.
We still can't observe black holes directly, only their large-scale effects, and even those can be hard to unambiguously make out. As far as I know we don't have perfectly solid evidence they exist yet (although lots of circumstantial evidence, so to speak).
The main process that can create black holes that we know of are supernovae. There hasn't been one near enough to study closely, which is good, because it'd probably fry us if it was. As >>49 mentions, these things happen over astronomical timescales, which is far longer than humans have been around.
And black holes are thought to disappear by Hawking radiation, but the timescales involved for that are beyond anything you can imagine.
OK. It seems we'll have to wait for the CERN's LH Collider in 2007 to (hopefully) crank out mini black holes to study before we can map fully the black hole's properties.
Before you can ask yourself "is time travel possible?", you first must ask yourslef "what is the nature of time?". We don't know for sure that time really physically exists at all, it may just be a concept that we associate with the changes in the world around us, and use to chart the progress of those changes, a concept we have become so dependant on that we view it as something physical that can be seen or changed or altered. The fact is we don't know for sure that time is a physical thing at all, it may just be all in our heads, a psychological crutch, if you will.
On the other hand maybe it is. And then you have to wonder what it's physical propertys are. Is it a dimension, a fourth axis on which we are constantly moving? Or perhaps it's some other physical thing. The fact is, it is at our current stage of thought impossible to prove or disprove even the EXISTANCE of time, let alone weather we can alter it's course.
Before you can ask yourself "is space travel possible?", you first must ask yourslef "what is the nature of space?". We don't know for sure that space really physically exists at all, it may just be a concept that we associate with the changes in the world around us, and use to chart the progress of those changes, a concept we have become so dependant on that we view it as something physical that can be seen or changed or altered. The fact is we don't know for sure that space is a physical thing at all, it may just be all in our heads, a psychological crutch, if you will.
On the other hand maybe it is. And then you have to wonder what it's physical propertys are. Is it a dimension, a fourth axis on which we are constantly moving? Or perhaps it's some other physical thing. The fact is, it is at our current stage of thought impossible to prove or disprove even the EXISTANCE of space, let alone weather we can alter it's course.
>>53 Um, we're not talking about the philosophy of existence but the observable nature of spacetime. So, please don't bring psychology into a discussion of physics. You may be correct, we could all be brains placed in a jar and fed stimulation to see our reactions but since we can't measure that scientifically we discuss the things we can measure. And by our mathematics and knowledge of physics time travel IS possible.
> The fact is we don't know for sure that time is a physical thing at all, it may just be all in our heads, a psychological crutch, if you will.
Spoken like a true philosopher with no knowledge whatsoever about the actual physics of what he is talking about. When you say "we", you really mean "I", don't you?
Before you sprout statements like this again, maybe you should take some time to study what we actually do know about time?
To understand timetravel one must first understand time and if this 'time' really exists.
Is traveling faster than the light timetravel? We are looking up at the stars and looking back in "time" beacuse the light is extremely slow when it comes to interstellar distances.
When we look at the moon it is 1 second in the past and if there was an astronaut up there we would know he sees us 1 sec in the past aswell.
How is it possible for us to look back in time yet not be able to travel there?
> Is traveling faster than the light timetravel?
No, because there is no such thing as "traveling faster than light".
> How is it possible for us to look back in time yet not be able to travel there?
How is it possible for me to look at women yet not be able to become one?
To understand spacetravel one must first understand space and if this 'space' really exists.
(...wait, I already did this joke earlier in this thread.)
>No, because there is no such thing as "traveling faster than light".
I know we aren't able to travel faster than light.. YET!
Why can you travel @ the speed of light (light does this) but not actually go 1m/s faster than it?
Just because you cant see an object doesn't mean it stops to exist.
We can travel faster than sound, but it doesn't mean that sound stops to exist (pilots still hear themselves breathe and stuff).
and i mean 'faster than the speed of light'.. not light itself -__-;
>How is it possible for me to look at women yet not be able to become one?
Becoming something is not the same as traveling to something.
> Why can you travel @ the speed of light (light does this) but not actually go 1m/s faster than it?
Because "1m/s faster than light" is a meaningless concept. You only think it makes sense because you are used to very low velocities. Your intuitive image of the universe is nowhere near correct, and it is that incorrect image which makes you think moving faster than light makes sense.
It has nothing to do with light itself. Light just happens to move at the maximum possible speed. The structure of the universe is such that moving faster than light is not something that can happen.
> Becoming something is not the same as traveling to something.
Similarly, seeing something is not the same as travelling to it.
>the maximum possible speed. The structure of the universe is such that moving faster than light is not something that can happen.
yeah, and there cant be life without water... lolz
I am telling you the truth, but you refuse to listen, so what can I do? Well, I guess I can tell you what happens if you try to go faster than light. Please try and read and understand at least some of this.
Let's say you build a rocket with a REALLY big and powerful, yet extremely light-weight, engine. This is currently impossible, but that might just be engineering so we can easily disregard it, as you like to do.
In the first case, let's just set off the rocket and watch it go. You'll see it accelerate up towards the speed of light, just as you expect. However, when it starts to get close, you notice it's not accelerating as much as it should any longer. This is pretty confusing, since the engine is still putting out just as much thrust. Investigating closer (with your strange futuristic equipment), you notice that although the engine is still running correctly, the rocket is suddenly heavier. You will also notice that the close to the speed of light you get, the heavier the rocket will become, and the less it will accelerate.
When the rocket gets really close to the speed of light, its mass has grown enormous. The engine still tries to accelerate it, but it's not doing much good any longer. It will never reach the speed of light, but if it did, its mass would be infinite, and the engine could no longer move the rocket.
Incidentially, you will also find that the rocket has become shorter, and that clocks on board it are running slow. If the rocket should ever reach the speed of light, it would be completely flat, and time would stand still on board it.
Now, in the second test, let's jump aboard that rocket and try to ride it up to the speed of light. At first, everything goes well. The rocket accelerates just as it should. From our previous experiment, we might expect that it will soon stop doing this, because of the mass increase. However, to our surprise, everything is working just fine. But when we look out of the window, we suddenly notice that the entire universe around is shrinking along the direction of travel. Even though we keep accelerating, we never seem to get past the speed of light relative to anything outside the rocket - we reach places that used to be far away quickly, but it is not because we ourselves are moving fast, it's because the rest of the universe is shrinking!
We will reach Alpha Centauri in, say, three hours. But we know from our previous experiment that that rocket reached Alpha Centauri in three hours too, by its internal clock, which was running slow!. Sitting outside the rocket and waiting for it to reach Alpha Centauri took the expected four years, but the internal clock had slowed down so much, it only ever counted up three hours.
None of this is fanciful theory - this is all confirmed every single day, by particle accelerators and GPS satellites. This is how the universe works. It seems very strange, and it seems totally wrong compared to our experience, but it is actually our experience that is incorrect.
ok suppose that we have a looooooooooong tube with inside diameter of 1 cm and length of 10 light seconds. and in side this tube is full of small 0.9 cm metallic spheres lined up from one end to the other. so you push the first sphere. with common sense, you might think that on the other end of our tube, a sphere drops instantaneously right? I mean, nothing is moving faster that the speed of light right? you are just pushing one sphere slowly and on the other end, no matter how long the tube is, one should come out of the tube.
sorry pal, but that’s not the case, its going to take 10 seconds. Practical observation: electricity , more or less is the same concept and it doesn’t travel faster than light. if can’t defy space. how are you going to defy time? the two are closely connect as far as I have heard. so nope: no time travel unless you break space and the laws of universe in some manner.
scientists are known to have slowed the speed of light down, and there was an incident in a russian nuclear reactor, i cant remember what it was, but there was some matter that travelet faster than the speed of light.
google for it, it's there..
Light travels at less than "the speed of light" in a medium. When people say "the speed of light", they actually mean "the speed of light in a vacuum", also known as c. Travelling faster than the speed of light in a medium is not only possible, it happens all the time around nuclear reactors. It causes a phenomenom known as Cherenkov radiation, which incidentially is quite pretty: http://images.vertmarkets.com/crlive/files/Images/8B3B7B58-B579-11D4-8C77-009027DE0829/jgglow.jpg
This is why the "light" part of "the speed of light" is not important. Light doesn't always travel at the "speed of light". The constant c exists independently of the fact that light travels at that speed in a vaccuum. Other things travel at that speed too - gravity being one of them.
im not talking about light itself.. just the speed it has.
Didn't Kurt Godel have something important to say about time travel in relative space.
Gödel was a mathematician, not a physicist.
From Wikipedia's article on "Kurt Godel."
"In the late 1940s, Gödel demonstrated the existence of paradoxical solutions to Albert Einstein's field equations in general relativity. These 'rotating universes' would allow time travel and caused Einstein to have doubts about his own theory."
More detailed information about this body of work can be found here:
http://infoshare1.princeton.edu/libraries/firestone/rbsc/finding_aids/mathoral/pmcxgod0.htm
Also, 72GET!!!
Well, you learn something new every day!
almost. it does happen pretty much simultaneously with the first ball. it will simply take 10 seconds to observe the ball fall out of place, because of the distance the light has to travel to reach back to you. an observer at the other end will see the ball fall out of the tube before you push it, in theory. thats also assuming you can even move that many small metal bearings. they should weigh in the vicinity of several tonnes.
That's plain and simply wrong. It will take at least 10 seconds, in practice much, much longer, before the last ball starts to move. The reason it takes longer is that the pressure will move through the system at the speed of sound, not the speed of light. The speed of sound in a metal is pretty high, but it's much less than the speed of light.
>>75
so the energy you apply to item #1 moves to item #2 and so on. but, assuming we has something strong enough to push them all, wouldnt that mean that either 1) the metallic bearings would change shape, or even break under the pressure or 2) two bearings will occupy the same space at the same time. assuming the bearings are indestructable, neither scenario seems likely. but im also imagining a constant application of pressure, not a impact, like you see on those desk-ornaments with the balls on string.
using that balls-on-string example, lets say you have one of those desk ornaments. if you pick up one ball, and let go, the last ball moves. i understand thats because of the energy wave moving, and i understand it happens at the speed of sound. but do you mean to tell me that if, for instance, you had those five balls at rest next to each other, and you pushed one, (not drawing it back and releasing, just pushing it foward) that the balls dont move as if they were one object? the same thing should happen in this tube. if one thing is pushing on these bearings, then all the bearings should move in unison, so long as the force is sufficient enough to move them all.
> wouldnt that mean that either 1) the metallic bearings would change shape, or even break under the pressure
Yes.
> assuming the bearings are indestructable
They are not, and no such material exists, or even can exist.
> but do you mean to tell me that if, for instance, you had those five balls at rest next to each other, and you pushed one, (not drawing it back and releasing, just pushing it foward) that the balls dont move as if they were one object?
Yes, I mean exactly that. It is not noticable under normal circumstances because the speed of sound in the material is so high in comparison to the speed you move them at, which is why your intuitive sense of the world does not accept it easily.
>>59 The only way to travel faster than the speed of light is by cheating. Usually this involves parallel dimensions or creating a "warp bubble" around you spaceship.
The reason you can't travel faster than light is, basically, because you can't.
It's possible. Very likely too if you consider the following "time travel"
You could build spaceship that accelerates at 1g. It would take you 24 years to get to Andromeda galaxy in your time frame, remember you would be going at relativistic speeds (time dilation). But us here on earth, we would see you on your way for millions of years.
http://www.dailygalaxy.com/my_weblog/2007/07/weird-science-2.html
There. I guess it's not just normal people who believe this shit. The project funders must have too much money in their hands.
If time travel to the past was possible, we'd currently be flooded by otakus from the future who want to catch original broadcasts of Lucky Star.
>>82 The RIAA from the future will not allow it for copyright reasons.
Believe Einstein. I think you can go into the future if you can travel at the speed of light. I think it's true that it is relative to the space you are in so as you travel at the speed of light it might not seem like you have aged but you return and everyone else will be older depending on how long you were away. Maybe it is not time travel but age travel.
Semantics.
I'm going into the future right now!
reverse the polarity.
Great Scott! Where are you going to find 1.21 gigawatts??
all time is occurring simultaneously. It's like pictures in a flip-book. All other informationis classified.
no its not possible, period.
It's real, and I can prove it!
I just don't feel like it...
SEE I DID IT!!
Nobody managed to go backward, and so far it seems impossible,...
I can go backward any time, the problem is how to bring my body with me.
I managed to do it at least to years ending in "5", and then I had to go and wreck the delorean... At least now I have something that travels between years ending in "7", so welcome summer of love!
Stephen Hawking once tried to prove time travel was impossible by means of a convoluted argument that took into account several factors, and then tried to argue that all of them didn't work, probably in an effort to explain why he considered such things as the "grandfather paradox" to be impossible. Seems to run afoul of Occam's Razor to me (but I wish I remembered the argument). There is another school of thought: that if people were to travel back in time and change history, they'd wind up in an alternative universe or in another timeline (and THAT has spawned an entire science fiction subgenre itself).
Some physicists (such as Michio Kaku) have argued that time travel is possible in theory, via means such as wormholes and heating up things so much that wormholes appear. Hawking contends that wormholes would collapse as soon as someone attempts to send light (or information) back in time through it. (And some s.f. authors, such as Stephen Baxter, have tried to cash in on such subjects - "The Light of Other Days", along with time travel stories).
>>98 There is a third option. In some of the Philadelphia Experiments (Scifi or truth? We may never know.) they sent some accomplice back in time to kill the father of some guy, but when the killer came back there was no change in the present. The only thing that changed was that the memory of the father of the guy was somehow fading away.
100 Get
With an infinitely powerful telescope and an unending search of the night sky, perhaps one could peek around the corner of a singularity 500 million light years away and see a billion-year old Earth. Just see what it looked like then, of course.
If it were possible to cause changes in the past that affect the present, I'm sure we'd have know about it already due to the swarm of interlopers coming back to give high-fives to us people from the Stupid Ages.
But what about the possibility that the time machine has to be stationary (a la Ronald Mallett and his "time machine")?
In other words, you don't travel with the time machine like in back to the future, but instead travel TO the time machine at an earlier point in time. This means that it would be impossible to travel back further than when the first time machine existed, because there would be no arrival point.
Meaning, no one from the future can come to this time because a time machine hasn't been invented yet.
(Keep in mind I am basing this off of a documentary I saw a few years ago, so please correct me if I have misrepresented Mr. Mallett's theories).
OK, point on the speed of a tube of ball bearings 10 light second long. It would take approx. 139 hours, assuming the ball bearings are perfectly aligned and made of steel, for the "information" that the first ball bearing moved to reach the last one.
I know the fact it moves at the speed of sound has already been pointed out, I just thought I'd throw a number next to it.
There are two types forces through a median - longitudinal vibrations and transverse vibrations. Since we are compressing the metal bearings, we want longitudinal vibrations. The speed of longitudinal vibrations through steel is about 6000 m/s.
Also, since there seems to have been some misunderstanding...
as long as the ball bearings are all aligned correctly, they behave EXACTLY like a single unit, except for the last one which will pop out.
Interestingly, a cylinder that is infinitely massive would be unable to be compressed, and it seems that the information of a force should be instantaneous through it, right? Not that it would matter, since it could obviously not exist, but still, it's a curious question.
Also, another question. Since light moves at the speed of light (or very, very close to it), from the perspective of the light (if you can imagine such a thing), would the light exist along all of its paths at once, if we ignore any time it hits a medium that slows it down?
> Interestingly, a cylinder that is infinitely massive would be unable to be compressed, and it seems that the information of a force should be instantaneous through it, right?
You're making the usual mistake here of thinking of a "solid" as something that actually exists. "Solid" is an intuitive shorthand we use for something which is actually very, very different.
Think about what a "solid" actually is: It's a bunch of atoms packed together, sometimes in a crystal lattice. An atom, on the other hand, is a tiny nucleus surrounded by an electron cloud.
What happens when sound is transmitted is that the atoms move, and their electron clouds push up against each other, and repel because they have similar charges. Now you question becomes, what do you mean by "infinitely massive"? Do you have infinitely massive nuclei with normal electron clouds? Do you have an infinite number of nuclei packed into a finite volumes? What happens to the electron clouds then?
And so on. The answer you end up with is that your question is meaningless and unanswerable, because the situation makes no sense physically.
Now you question becomes, what do you mean by "infinitely massive"? Do you have infinitely massive nuclei with normal electron clouds? Do you have an infinite number of nuclei packed into a finite volumes?
What happens to the electron clouds then?
Quark-gluon plasma.
>>104
Quark star? Isn't that basically "infinitely compressed", such that it is a solid piece of matter, as much as we understand matter to be? A collection of free quarks gathered together to form, essentially, a single particle of a size similar to a neutron star? If so, that material would be, intuitively at least, unable to support shock waves through it.
And though this is somewhat unrelated, isn't the inside of a black hole considered to be infinitely massive and infinitely small by some? I've read that several times, and it seems blatantly wrong, but maybe it is and I'm just not understanding how gravity works.
> isn't the inside of a black hole considered to be infinitely massive and infinitely small by some?
I imagine that's just poetic license taken by some cheap science fiction writer.
>>107
Actually, cheap science books. Not that there is a huge difference...
That would still be entirely finite.
What about 10 dimensions or M theory?
In the year of '39 assembled here the Volunteers
In the days when lands were few
Here the ship sailed out into the blue and sunny morn
The sweetest sight ever seen.
And the night followed day
And the story tellers say
That the score brave souls inside
For many a lonely day sailed across the milky seas
Ne'er looked back, never feared, never cried.
Don't you hear my call though you're many years away
Don't you hear me calling you
Write your letters in the sand
For the day I take your hand
In the land that our grandchildren knew.
In the year of '39 came a ship in from the blue
The volunteers came home that day
And they bring good news of a world so newly born
Though their hearts so heavily weigh
For the earth is old and grey, little darlin' we'll away
But my love this cannot be
For so many years have gone though I'm older but a year
Your mother's eyes from your eyes cry to me.
Don't you hear my call though you're many years away
Don't you hear me calling you
All the letters in the sand cannot heal me like your hand
For my life
Still ahead
Pity Me.
>>103
I recently read somewhere (I don't remember where) that they're toying with the idea of time as a 4th dimension of space. It seems to me to make sense, but in any case, if it is, I don't think I can say yes to "Since light moves at the speed of light (or very, very close to it), from the perspective of the light (if you can imagine such a thing), would the light exist along all of its paths at once, if we ignore any time it hits a medium that slows it down?"
If time were itself a dimension (what could have happened in this universe without it AND the dimensions of space?), I would have to assume that light moves within the dimensions of space (albeit at an incredible rate), according to the laws of time (which is presumably the only truly 'instantaneous' 'thing'). The actual speed time moves at, as opposed to the speeds things move about inside it, is the speed we have to beat to go forwards. Even then, I don't think we could pin-point A time and zap ourselves there. We'd exist in the 3 dimensions of space, going forwards through time quite literally (as one goes forward through time in their day to day lives). Going backwards seems to me, on this basis, impossible.
Time has been considered a fourth dimension of space-time for a hundred years, soon. Note, however, that that is specifically space-time, not space. The spatial dimensions are different from the time dimension, although they together form a whole.
What about the 6 other dimensions of space!
http://revver.com/video/99898/imagining-the-tenth-dimension/
I wouldn't worry about them until the spring theorists actually manage to find some actual experimental evidence.
But if time is a dimension then it should mean we can go back in time, and we have seen that it's highly unlikely. Therefore time can't be a dimension... or that it's a special, one-way dimension?
I have always thought that to defeat that paradox, when you go "back" in time, you are always just traveling to a parallel dimension, therefore no paradox can occur, fine kill the your mum in that universe, your still there and fine.
It is a dimension, but it is a time-like dimension instead of a space-like one. The Minkowski metric, which describes flat space-time, contains ones for the three space-like dimensions, and a -1 for time: http://mathworld.wolfram.com/MinkowskiMetric.html
There is really no explanation for why our universe can be described with such a metric, but it can, and thus we are stuck with three space-like and one time-like dimension.
i think it's more like this:
You travel back in time. INSTANTLY, just by appearing in the "past" you have changed that universe irrevocably. A paralell universe is the result, you kill your grandpa, you travel forward in time to the present. Everything seems fine, you don't die because you're actually from a paralell universe, but in that universe you never existed. and life goes on. however, it is not your universe anymore, and you never return to the "present" of your own universe. Nor does the history of your universe become altered.
now that i type it all out, though, it does all seem rather arbitrary - is there any proof of paralell universes?
> is there any proof of paralell universes?
Not yet, and there may never be any.
Time-travel is indeed possible. We know the mathematics and methods of how to bend time and space. The only problem is our energy constraints. It would take all the energy of our solar system PLUS that of another to actually travel in time.
>>121
So, two portable black holes? Yup, that's what John Titor was/will be using. Created by CERN's Large Hadron Collider in the near furure. Currently scheduled to begin operation in May 2008.
that's just plain false. The likelihood of creating a black hole is small, like one a second, when considering the scale of time with particle physics. Next, the holes themselves would be too unstable as such a small scale, meaning they won't last, and FINALLY, even if a black whole were to be created, and be able to stick around long enough to acrete the earth, it would evaporate instantly from (they still technically unproven) hawking radiation. If making black holes to destroy the earth was that easy, some jerkass would have done it by now - or the universe would be CONSTANTLY hurling black holes everywhere.
>>123
No, those mini black holes created by Man would not destroy the Earth. They probably wouldn't even sink below ground, they would evaporate. The actual danger would come from the evaporation point, with plenty of heat and radiations.
Not all black holes are stellar-size-massive. The braneworld theory predicts the existence of tiny black holes seeded throughout the universe, remnants of the Big Bang. And that thousands of them should exist in our solar system.
that's what i was trying to say, but i guess i forgot to mention they were really tiny, which is important.
Okay. Next, how much energy does a black hole needs to be? If we look at John Tytor's time machine manual, we see in the "Emergency procedures" section: "Unit self-destruct is pilot controlled. The singularities will automatically evaporate with a compromise in the containment field. A nuclear explosion with the equivalent of 2x megatons will detonate upon singularity evaporation."
So we'll need to get the CERN to cram 20-29 megatons of energy into a singularity. Then we'll be able to time travel.
Oh, and incidentally we'll also need to invent that "containment field" first if we don't want the CERN to vanish. So far it doesn't exist yet... :)
>>Not all black holes are stellar-size-massive. The braneworld theory predicts the existence of tiny black holes seeded throughout the universe, remnants of the Big Bang. And that thousands of them should exist in our solar system.
Holy Magnetic Monopoles, Batman! Wasn't this one of Stephen Hawking's predictions from, like, 1972? And hasn't he abandoned it and moved on?
I already figured out time travel. The problem isn't getting to there. It's getting from here.
