Time Travel Theories:

[DeadZero]

Let's say you build a time machine, and go back in time. The instant you go back in time, the VERY instant it changes one thing, one whiff of air. You just stepped on a butterfly. The whiff of air changes the other whiffs of air around it, which change the whiffs of air around them and etc, all those whiffs move a leaf or a piece of paper, that leaf or piece of paper or whatever the whiff changed will change something else, possibly another whiff. This is a chain reaction which will continue throughout the entire universe. This chain reaction will obviously change the future, changing how you go back in time if you do at all, when you change that you change when you got back in time and stepped on the butterfly. This changes history. The entire space time continuim will be ahniliated by a wave and rip in space time. Your whole life is a series of butterflies that you can choose to step on, every one changes the future of everything. This brings me to time travel, into the future. This is not a bad thing and does not have concequences UNLESS you travel back into the past. Future time travel is also possible, you just have to create a devise that can travel you or itself faster than the speed of light, fly atleast out of the galaxy and then back. It will seem like less than a billisecond to you but to the rest of the world it will be many, many years. This is of course theoretical but should work, the only problem with this theory is that if Why would you travel that far in the first place, it's obvious that the entire world is going to be a giant junk yard, air will cost as much as water because the air will be unbreathable. This is of course another theory.you went faster than the speed of light, what would happen? Your moliquiles would go faster than anything in the universe, how could you stop? How could you stop yourself from vaporising?

My question is, do what do you think? About everything. Please be respectful of my theories and keep an open mind.

 

[PurplePoot]

Well, seeing as particle motion is nonrandom you might say that what occurs is inevitable and thus you aren't changing anything.

 

[Duragon]

You cannot move faster than the speed of light if you carry information. (The envelope velocities of wave packets can travel faster than the speed of light for instance, but they carry none of the information of the wave) The idea that you become "infinitely stretched" when moving at velocities close to the speed of light is a very common misconception. In reality, you actually become increasingly contracted (shrunken) in the direction parallel to motion. Furthermore, this is a relative effect, so you aren't actually contracted, you just appear contracted to the observer in relative motion with you.

Anyways, that's a bit beyond the scope of this topic. Suffice to say that you cannot move faster than the speed of light or we would need to remake numerous portions of our physics. (As most of it would then be absolutely wrong)

About time travel, it really depends if you believe in determinism or not. The causality of the universe boils the discussion to two points:

• You can go back in time and thus change the course of history, but your existence is an effect caused by a chain of events in another reality that is no longer reality. You now "exist" in the new universe, and your changing the universe will not remove you from it by retro action with the previous, now-false, reality.
• You can go back in time and thus change the course of history, but your existence in the new reality is non-deterministic. Now that these two realities are somehow intricately linked, your changing anything in this new reality retroactively impacts the old reality and may undo your capacity to even change the new reality at all. (Because they cyclically interact in a non-deterministic way)

Which is real? Who knows at this point in time. I'd like to believe the former.

 

[Vulcano]

Well, seeing as particle motion is nonrandom you might say that what occurs is inevitable and thus you aren't changing anything.

It's not nonrandom, delta x is the accuracy of the position of a particle (or just a human body, but then delta x is very small):

. If you had chemistry on school and you saw orbital theory then you now know why we talk about orbitals(= space were you have a 95% chance that the electron is there) and not about the exact place of the electron.

And you can't go faster than c.
But if it can than most things you said are correct. Although traveling to the past could also change nothing because of the random factor it can also turns out the same as it was before you travelled to the past. Anyway, its 100% hypothetical and thus quite stupid anyway.

 

[DeadZero]

Yeah, it's possible that when you go back in time the things that happen to your time line already happened because you were back in time before you went back in time, so nothing would happen. Like if you could tell the future you would not be able to change it because if you changed the future the future that you told woulden't be the future, it would be nothing. So there's some chance for you to not create a time paradox...

 

[Ironside]

Well my theory is that if you traveled back in time, you could kill let's say Hitler from doing everything he did, but when you came back to where you were when you used the machine, nothing changes...

My opinion is that the past is impossible to change...

As for future... same i guess...

 

[Mulgrim]

so don't breath! brilliant!

 

[Duragon]

It's not nonrandom, delta x is the accuracy of the position of a particle (or just a human body, but then delta x is very small):

. If you had chemistry on school and you saw orbital theory then you now know why we talk about orbitals(= space were you have a 95% chance that the electron is there) and not about the exact place of the electron.

That form of the uncertainty principle has no bearing on the way particles move, only how well you can know where they are based on how well you know their linear momentum.

 

[Vampiro320]

Why do you guys always talk about such confusing things?

 

[Vosty]

So the butterfly thing...
Might make you NOT want to go back in time, because changing time, could cause you to not exist, but you can't stop yourself from existing if you never existed, because you couldn't go back in time, meaning that you couldn't go back and stop yourself, causing you to exist, so you could go back and stop yourself.
WAIT! Stupid Time loops!
For instance, going back in time could accidentally lead to the human race having a third eye atop your head, or Al Gore being king of the world, or Einstein being dumb, meaning no nuclear weapons.....

 

[DeadZero]

That's exactly what I meant but the wave would be universal.
Mulgrim, standing in one place changes the way the air moves, not counting about the effects that time travel would have on the area...

 

[TwistedImage]

I both think and hope time travel isn't possible.

Coloured text makes my eyes bleed.

 

[PurplePoot]

It's not nonrandom, delta x is the accuracy of the position of a particle (or just a human body, but then delta x is very small):

. If you had chemistry on school and you saw orbital theory then you now know why we talk about orbitals(= space were you have a 95% chance that the electron is there) and not about the exact place of the electron.

And you can't go faster than c.
But if it can than most things you said are correct. Although traveling to the past could also change nothing because of the random factor it can also turns out the same as it was before you travelled to the past. Anyway, its 100% hypothetical and thus quite stupid anyway.

I'm well aware of the Heisenberg Uncertainty Principle (and related QED/QCD), but not only is that uncertainty (and not variance), but that only applies on subatomic scales and for incredibly short periods of time. In larger systems or on larger time scales motion is effectively nonrandom.

 

[Mulgrim]

even though science keeps popping bubbles and finding loopholes to end our fun, i would personally like to see my birth.

That's exactly what I meant but the wave would be universal.
Mulgrim, standing in one place changes the way the air moves, not counting about the effects that time travel would have on the area...

so sit, dur!

 

[Peter Canvis]

What time travelling means is moving your atoms into a certain position. 7th grade chemistry explains the atoms and describes how everything around us is made of very small atoms we can't see. Even we are made of atoms. Time travelling would imply seperating all our atoms and making them travel with the speed of light so that we would go back in time, as for teleportation it would be the same, If someone discovers teleportetion then automaticly by logical deduction, time travelling will be possible also. Scientists say that a time machine would cause massive damage to world, because then someone could just go back in time and give a computer to a cave man.

 

[Peter Canvis]

What time travelling means is moving your atoms into a certain position. 7th grade chemistry explains the atoms and describes how everything around us is made of very small atoms we can't see. Even we are made of atoms. Time travelling would imply seperating all our atoms and making them travel with the speed of light so that we would go back in time, as for teleportation it would be the same, If someone discovers teleportetion then automaticly by logical deduction, time travelling will be possible also. Scientists say that a time machine would cause massive damage to world, because then someone could just go back in time and give a computer to a cave man.

 

[TwistedImage]

I didn't have chemistry in seventh grade.

I still don't.

Either way I think we all knew that, and the scientists are correct. If I got my hands on one I'd exterminate the early monkeys to prevent it from happening <.<

 

[Duragon]

...and for incredibly short periods of time

That's incorrect. Only the dEdT form of the uncertainty principle requires short periods of time, and that is only for knowing a definite energy of the waveform.

In larger systems or on larger time scales motion is effectively nonrandom.

You mean particle motion at the Newtonian scale is deterministic, not necessarily nonrandom. Chaotic systems are potentially random in our description of them based on infinitesimally small deviations in measurement of the state vector. (This is a minor technicality at best, since the motion is still deterministic) On the Planck scale, particle motion is probabilistic and thus effectively random.

 

[Vosty]

even though science keeps popping bubbles and finding loopholes to end our fun, i would personally like to see my birth.

What the fook!

 

[PurplePoot]

What time travelling means is moving your atoms into a certain position. 7th grade chemistry explains the atoms and describes how everything around us is made of very small atoms we can't see. Even we are made of atoms. Time travelling would imply seperating all our atoms and making them travel with the speed of light so that we would go back in time, as for teleportation it would be the same, If someone discovers teleportetion then automaticly by logical deduction, time travelling will be possible also. Scientists say that a time machine would cause massive damage to world, because then someone could just go back in time and give a computer to a cave man.

Erm,

• Massive objects cannot travel at the speed of light.
• Objects traveling at the speed of light do not move backwards in time; rather, they do not move at all in time.

That's incorrect. Only the dEdT form of the uncertainty principle requires short periods of time, and that is only for knowing a definite energy of the waveform.

The two forms are essentially equivalent, and regardless of that the one we care about is in fact ∆E∆t≥h/4π, since it tells us that any variation in energy (say, momentum) can only occur for a very short period of time and then must be negated if energy is to be conserved.

You mean particle motion at the Newtonian scale is deterministic, not necessarily nonrandom. Chaotic systems are potentially random in our description of them based on infinitesimally small deviations in measurement of the state vector. (This is a minor technicality at best, since the motion is still deterministic) On the Planck scale, particle motion is probabilistic and thus effectively random.

We see many subatomic phenomena that do not apply in larger systems; this is one of them. The numbers concerned are so small that they do not affect anything more than a local area and for a short period of time, as mentioned above.

 

[Duragon]

The two forms are essentially equivalent, and regardless of that the one we care about is in fact ∆E∆t≥h/4π, since it tells us that any variation in energy (say, momentum) can only occur for a very short period of time and then must be negated if energy is to be conserved.

Your misconception is a common one, since you can always rewrite one in terms of the other (E=hf,c=L/f, derived the same way), but they are standing different versions of the uncertainty principle for a reason. When you are discussing motion, or deviation of a position, you cannot relate it to a fraction of time via the uncertainty principle without introducing momentum. Even the dEdx uncertainty principle is proportional via an inequality to the expectation of Px. Only energy is uncertain with regard to time, and it is because over a short enough period of time, you cannot ascertain the true energy of a waveform since you don't have a definite frequency.

Basically, if you want to talk about time, you must talk about energy, not momentum. The change of kinetic energy seen by shifts in linear momentum doesn't account for total energy of the waveform, which is necessary to discuss time at all in the uncertainty principle.

We see many subatomic phenomena that do not apply in larger systems; this is one of them. The numbers concerned are so small that they do not affect anything more than a local area and for a short period of time, as mentioned above.

You basically just repeated yourself as if I didn't understand your original point. I did. I was clarifying that randomness of Newtonian motion does exist in a practical sense because the accuracy of measurement is crucial to chaotic systems. Sorry if I wasn't clear enough in my previous post.

 

[PurplePoot]

You basically just repeated yourself as if I didn't understand your original point. I did. I was clarifying that randomness of Newtonian motion does exist in a practical sense because the accuracy of measurement is crucial to chaotic systems. Sorry if I wasn't clear enough in my previous post.

Guess I misread and wasn't thinking totally straight. Sorry, I'm still a tad groggy since I just woke up recently.

Anyhow, I was and am under the impression that chaotic systems are not random so much as sufficiently complex (with enough variables) that they are essentially impossible for us to understand at the moment. At large scales, that is. There is a difference between perceived and true randomness.

 

[Slaydon]

Ehmm, i dont think you'd survive the past, and if that even happened, i just think the technology would be abit less advanced than it is today, like the computer invention

 

[Duragon]

Guess I misread and wasn't thinking totally straight. Sorry, I'm still a tad groggy since I just woke up recently.

It's okay.

Anyhow, I was and am under the impression that chaotic systems are not random so much as sufficiently complex (with enough variables) that they are essentially impossible for us to understand at the moment. At large scales, that is.

Chaotic systems aren't random per se, hence my previous post using "practical" as a qualifier. Because they vary so dramatically based on initial conditions, the imperfect (and oftentimes based in quantum effects) precision of the instruments with which we measure the initial conditions can lead to seemingly random outcomes.

There is a difference between perceived and true randomness.

Absolutely, again, hence the qualifier 'practical.' For all practical purposes, whether it is truly random or simply random by inheritance from imperfect initial conditions, it is random. It was just a passing note of my previous posts, is all.

 

[PurplePoot]

Well then, it seems we don't really disagree after all.

 

[Textor]

If you would do for sample something bad , evil in your life and you want to make it good , lets say there is a time machine and you use it , then you go back and dont do the bad thing but then your past you have no reason in future get back in the time to do something better , de javu ?
Thats just a idea , i love talking about time traveling its perfectly confusing

 

[kids711]

When you Time Traveled in the Future, You can change the Past by moving a piece of paper or whatsoever, It doesn't mean if your in the Future you can't change anything?.Once you step on a butterfly this could change your Future more heavily than ever.. For example.. You found your Future Friend and accidentally hits him with a Baseball bat.. Then in the future, She will never know you or meet you. Or she won't even exist.When you Traveled in the Past. Every step of your foot could change the Future, Example when you step a building will fall, Then when you found out that your puppy will get killed by falling in the Building that time that day that year, You could save him and when u time traveled in the Present.. Your parents won't even matter about your Dog around them, They would ignore it like nothing happened from the past.

Sometimes when you met someone that is sooo very sad for loosing his/her loved ones. You can go back to the past and know what happened and stop this. For example her loved ones is going away with the train and she will be too late to tell him that shes pregnant. Then you remembered a clue that happened before the event took place, Example : A Car Crash that stopped her from running and got distracted. You could save the Victim so the Woman will never be late to tell her husband that shes pregnant and her husband will stay with her into the Present, Once you came back to the Present you will meet her husband and the woman, Then they both will say "Hello, Whats your name".

 

[TwistedImage]

Can you remove colored text? Thanks.

 

[Peter Canvis]

Erm,

• Massive objects cannot travel at the speed of light.
• Objects traveling at the speed of light do not move backwards in time; rather, they do not move at all in time.

The two forms are essentially equivalent, and regardless of that the one we care about is in fact ∆E∆t≥h/4π, since it tells us that any variation in energy (say, momentum) can only occur for a very short period of time and then must be negated if energy is to be conserved.

We see many subatomic phenomena that do not apply in larger systems; this is one of them. The numbers concerned are so small that they do not affect anything more than a local area and for a short period of time, as mentioned above.

Massive objects are made out of particles/atoms, everything is, if you would've read my comment carefully you would've notice I'm trying to explain you that it would imply decomposing you into your initial shape and move you to another point particle by particle.

 

[PurplePoot]

Yeah, and your comment violates the laws of physics.

 

[Restor]

Travel in time is possible, Spock travelled throught blackhole

 

[Peter Canvis]

Yeah, and your comment violates the laws of physics.

Honestly, take a good look at my comment, humans have yet to find a way to seperate particles from a human being (Or any being, for that matter) but when they'll do I guarantee they'll be able to do more stuff than just puny time travell, they'll be able to send humans in other galaxies, right now it takes 4 million years to reach the nearest star in our universe with the fastest rocket on planet earth.

 

[PurplePoot]

Honestly, take a good look at my comment, humans have yet to find a way to seperate particles from a human being (Or any being, for that matter) but when they'll do I guarantee they'll be able to do more stuff than just puny time travell, they'll be able to send humans in other galaxies, right now it takes 4 million years to reach the nearest star in our universe with the fastest rocket on planet earth.

Massive objects cannot travel at the speed of light. This includes massive particles. In addition, nothing can travel faster than the speed of light.

 

[DeadZero]

Restor, we're not talking about Sci-Fi xD

Kids711, that's half of what I said with more examples, you missed the other half... doing one of those things would change something at the time when you traveled back therefor changing how or if you changed it changing how you traveled back changing how you traveled back changing how you traveled back changing how you traveled back changing how you traveled back changing how you traveled back changing how you traveled back x ∞. Bewm goes the space time continuim?

On a seperate arguement another possible result of time travel is that it would create an entirely new time line, the one that results from you going back in time, the other time line where you went back in time would be gone but the fact that you went back in time in the first place would stay, so you would be in a world that seems not so different originally but things will start to change. You'd probably be arrested for not existing according to computors (I don't want to get into an arguement for that)...

 

[Mulgrim]

just because i'm in a friendly environment and never google'd this, what's a black hole do? what's it's purpose

 

[TwistedImage]

Like everything else in the Universe, black holes don't have a purpose.

They use their extreme mass to suck everything (including light!) into themselves and making them collapse due to insane gravitational force.

My teacher also told me a black hole the size of the outer third of your index finger would weigh as much as the Himalayas.

 

[Mulgrim]

so it's just there to kill everything?

 

[TwistedImage]

As I said, I don't think anything is there for a particular reason. It just appeared randomly, like life.

 

[reason 3]

About the teleportation that has been mentioned...
I don't "teleportation" exists.You will just move TOO FAST to another point, so fast that neither and nothing could see you, thus creating the illusion of teleportation.

I think that even if you manage to exceed the speed of light nothing would really happen...just because you are moving fast means that you can jump into another reality into another world to a different time?

And for black holes i guess they surely have a reason to exist, we just don't know it yet.

 

[TwistedImage]

Well that depends how you define "reason." I'm under the impression that nothing was originally created for a reason, rather it just fit in with what was already there and stayed.

Or in the case of black holes, nothing could remove them. >_>

 

[uberfoop]

I don't "teleportation" exists.You will just move TOO FAST to another point, so fast that neither and nothing could see you, thus creating the illusion of teleportation.

I think that even if you manage to exceed the speed of light nothing would really happen...just because you are moving fast means that you can jump into another reality into another world to a different time?

You think these things because your notion of reality is based entirely on direct perception and newtonian mechanics. In a special relativity model, which is more or less a generalization of Newtonian mechanics to account for relative velocities, the universe behaves differently in different frames of reference, frames of reference being defined by differing relative velocities. Normally, these differences in reference frames can all be smoothly reconciled and preserve causalty and whatnot. However, when an object is moving faster than c in one reference frame, it can behave very strangely in other reference frames. Like, perform time travel. And just generally punch causalty in the face. And we don't like it when causalty gets punched in the face.

 

[WILL THE ALMIGHTY]

Haven't we gone over this subject eight times before?

 

[TwistedImage]

Repetition proves its worth again and again eh?

 

[PurplePoot]

The level of basic scientific illiteracy here is disturbing...

just because i'm in a friendly environment and never google'd this, what's a black hole do? what's it's purpose

Purpose?

As for what a black hole is, it's essentially an inevitable result of gravity under extreme conditions. Gravity is, on a per-unit basis, orders of magnitude weaker than any of the other forces. However, a per-unit comparison is not useful, since there tends to be more mass than, say, charge (well, there is plenty of charge, but it is mostly neutralized by opposite charge in its local region). Once enough mass is accumulated in a small enough area, gravity will overcome the electromagnetic force, creating what is called a "neutron star" (neutron due to the abnormally high neutron content as well as the fact that the neutron degeneracy pressure is the only thing keeping them from collapsing further (into a black hole) [thanks to Duragon for catching that I missed this!] and star due to the tendency for this to happen in the core of old (and large) stars); atoms will cease to be almost entirely empty space, and will instead be an essentially solid ball of matter. These generally rotate at enormous speeds (hundreds of times every second) and are about fifteen orders of magnitude denser than matter under more normal conditions (say, the sun).

However, gravity can go further still. While a neutron star is simply the result of gravity overcoming electromagnetism, gravity can overcome the other fundamental forces at even higher concentrations of mass. General relativity demands this (and it has been observed); essentially, if you think of gravity as the curvature of space time, a black hole is a point where all nearby space curves towards and yet never reaches (since a black hole does not have a size in the traditional sense). A black hole has what is called an "event horizon"; a sphere inside which nothing can possibly escape, even light. Thus, once an object has passed this horizon it essentially ceases to exist as far as any practical measure is concerned; inside the black hole it will be pulled apart and absorbed.

Note that black holes also warp time; an object passing through the event horizon will take an infinitely long time to do so as far as any other observer is concerned.

My teacher also told me a black hole the size of the outer third of your index finger would weigh as much as the Himalayas.

Black holes do not have a size in the traditional sense, so I'd like to see how this can possibly be justified.

Or in the case of black holes, nothing could remove them. >_>

Wrong. Hawking radiation (which is rather plausible, albeit obviously difficult to test) dictates that black holes can lose matter. For example, a black hole of the mass of the moon and in its location would more or less break even; it would absorb space dust, the occasional larger object, and cosmic radiation, and radiate a roughly equal amount of energy.

You think these things because your notion of reality is based entirely on direct perception and newtonian mechanics. In a special relativity model, which is more or less a generalization of Newtonian mechanics to account for relative velocities, the universe behaves differently in different frames of reference, frames of reference being defined by differing relative velocities. Normally, these differences in reference frames can all be smoothly reconciled and preserve causalty and whatnot. However, when an object is moving faster than c in one reference frame, it can behave very strangely in other reference frames. Like, perform time travel. And just generally punch causalty in the face. And we don't like it when causalty gets punched in the face.

An object cannot move faster than the speed of light in a reference frame, and a massive object cannot move at the speed of light in a reference frame. Two objects moving away from each other at 0.60c each will not separate at a rate of 1.20c.

 

[Duragon]

... creating what is called a "neutron star" (called this because this tends to happen in the core of old stars);

Your explanation is fine otherwise, but you're wrong here. It is called a neutron star because it collapses to a level where only the neutron degeneracy pressure (PEP, if you're into that nomenclature) prevents it from collapsing further into a singularity.

 

[PurplePoot]

Your explanation is fine otherwise, but you're wrong here. It is called a neutron star because it collapses to a level where only the neutron degeneracy pressure (PEP, if you're into that nomenclature) prevents it from collapsing further into a singularity. Furthermore, they're almost entirely made up of these neutrons.

I realize this; I was referencing the star bit, not the neutron bit. Guess I should have pointed that out though.

 

[Duragon]

I see. Your post certainly didn't imply you realizing it, though, hence my retort. My apologies.

The level of basic scientific illiteracy here is disturbing...

Anyways, on your previous post, I don't actually think even special relativity can be called basic. The last topic most college students see in physics is electricity and magnetism (integral form of Maxwell's equations). I can't help but find it normal for so many people to have so many misconceptions of time travel, the absoluteness of the speed of light (and its implications), and the actual physics of black holes.

 

[PurplePoot]

I see. Your post certainly didn't imply you realizing it, though, hence my retort.

I do not at all blame you. Regardless of my intention, the post does not come across clearly (which is what really matters), and thus your post is quite helpful nonetheless. I'll edit my post to throw it in and avoid further confusion.

Anyways, on your previous post, I don't actually think even special relativity can be called basic. The last topic most college students see in physics is electricity and magnetism (integral form of Maxwell's equations). I can't help but find it normal for so many people to have so many misconceptions of time travel, the absoluteness of the speed of light (and its implications), and the actual physics of black holes.

I don't mind people who don't understand * (physics, math, chemistry, biology, programming, philosophy, religion, whatever the subject is at the time) and understand that they don't understand it (for lack of better phrasing), but those who are convinced that their misconceptions are in fact totally valid regardless of criticism (notice some of the persistence earlier in the thread) and yet apparently don't care to do research are annoying.

 

[Restor]

Time travell is not possible.




Proof:

It it is possible, someone from future would travel here long time ago, and? Nothing happened.

Well, thats not proof, that time travell is impossible, but proof that mankind will never make it.

 

[PurplePoot]

Erm, no it isn't. I doubt it is possible, but that's a lame argument.