A Question about Time Travelling

[Nanfeishen]

We are assuming that time travel would mean a "physical" transition from time A to time B.

If time travel was to become possible, however IMHO, it would only be possible in the "unseen observer" capacity. There could and would be no interaction, as you would be "out of phase" in that time. You would have no more consistency than a ghost, you may appear as an apparition but nothing more.

 

[Arthur]

Depends on how slow you pour the water, if you pour it slower than than the time it takes for 500ml to evaporate then you should be fine

Or where you pour. Outside on Venus will be difficult. On Uranus will be, er, very hard.

 

[chrisc]

Whoever made this comment didnt really think about it, i wonder how he thought birds flew? Unless birds were thought to be lighter than air :erm: .

It was the chairman of the Royal Society, in 1876. He was a scientist, who, in his time was thought to utter profound truths. No-one in that era would have dared contradict him. The 1870's is several lifetimes removed from today.

 

[FrankCastle]

What if you can only go back to the point of your conception and the energy of your travelling self becomes fused with the developing fetus.
You grow up being able to see your own future up to the point where you went back in time.

 

[Swa]

1. That's a magical conception of the universe. The cosmos would have to 'know' that time travel was discovered, which would require that it somehow 'know' this in order for your barrier to be effective only from that date. Absurd.
2. Do you imagine a fascist future where that kind of control is in place? How would those who remain behind verify the breach? Why would a police-state send/allow people back in time?
3. The overwhelming majority of people in mental institutions do not have cognition problems (I asked my wife, who's a clinical psychologist). Only a fraction of certifiable people are institutionalised, so the majority of future time-travellers would in any case be roaming free; besides, mental institutions are a relatively recent invention. If there's no way for the future fascist police-state society to recover/remove the brain-damaged who went back to the past, one wonders why they'd bother sending people back in the first place, especially when they'd just inherit worse problems down the line. You might as well ask "what if they are here and we can't see them because they're invisible?". Back to magic.

1. Not really. You imagine a scenario where you pop away and pop into another time and place. It may be that you require a time machine to do the reconstruction or open a portal or something so that you can only travel to a time and place where it exists.

2. Similarly how would a person traveling back remember their own future and not the altered one. There may be a way of storing information about past events in some quantum state so changes are detectable. Also refer back to #1 if you can't pop out just anywhere in space a time travel event would be detectable. Besides just like nuclear weapons the technology is likely to not be widely available so again if #1 is the case the traveler would have to escape from a tightly secured facility too.

3. Sure but we don't know exactly what makes reality. Not magic but it's possible for a traveler to be out of phase with ours so that they are not observable.

The real reason why backward time travel is impossible even theoretically lies in the very architecture of matter and thus space-time. An ens mobile changes its relations to other entis mobile, and that rate of change we call time (broad summary). Causation runs linearly and cannot be run backwards without making everything incomprehensible and absurd.

This is most probably the reason it may not be possible. I doubt we can claim it's impossible though as we actually have no idea of the nature of matter. You adopt the idea that matter really undergoes change. The multiverse suggests everything already exists so you would only shift to another dimension. In the quantum state universe everything is undefined and definitive states are an illusion so you would only change consciousness.

The biggest problem I believe is actually our consciousness. How do we know we're still going to continue to experience being ourselves? It may be like transferring memory to another person. They can remember being us and claim to be us but we will not be the ones experiencing it so it will be like dying. This will also be a problem for transporters.

 

[Moosedrool]

 

[Rocket Raccoon]

Okay which one of you guys is gonna kill me in the future?

 

[azbob]

Okay which one of you guys is gonna kill me in the future?

None of us if Captain John Anderton has anything to do with it.

 

[DigitalSoldier]

Where did they park the 2212 Chevy?

Don't you thank that is a bit silly ?

We all know that they will be using DeLorians.

 

[Pietleeu]

Really?

 

[Swa]

Okay which one of you guys is gonna kill me in the future?

Don't you mean the past?

 

[DerekH]

Theoretically, time is the 4th dimension.
If this is true, then travelling in time would require us to enter that dimension and move in it.
I say this because we are currently able to move in 3 dimensions. Taking "Forward and backward" as an example, that enables us to travel in the first dimension. Now we add a steering mechanism and we are able to travel in the second dimension (Left and right).
Finally the Wright Brothers come along and give us a machine which lets us travel in the third dimension (up and down).
Let's say that we live in a one dimensional universe, where the only dimension is forward-backward. Someone crossing this universe in a left-right motion will be seen by the us as doing the impossible, appearing and disappearing as they pass through.
It logically follows that in order to travel in time, we first need to enter that dimension. We only experience time in the dimensions in which we exist, so our perception of time is extremely limited.
I'd say time travel is not possible because we do not have access to it's particular dimension, but rather only a component of it.

 

[RiaX]

Incorrect. Time is not theoretically the fourth dimension, it is the 4th dimension. Proven einstein's theory of space-time. Later verified practically by quantum theory and an atomic clock (though there are no absolute truths in physics).

You can see into the future and past by simple motion. You see when you are standing still you not really stationary you have velocity. Your full velocity is through time itself. Just like if you move north then travel north-west your velocity is divided in a westerly and nothern direction. Same thing happens with time, when you move through space, time slows down because your velocity is shared now between time and space. This was proven using an atomic clock, 2 clocks perfectly in sync one went for a plane ride the other sat still. The clock on the plane had a time that was slower than the stationary one, thus it proved in motion its time slowed down. This fact hold true with satelites in orbit, if you look at the development of the GPS the evidence is there, clocks on earth do not flow through time at the same speed as clocks in space.

Time can be stopped, which would give the illusion of traveling forward in time. Since time is inversly proportional to space your time will stop when you travel the maxium speed allowed in space i.e speed light. So if I were to travel one year at speed of light approximately 50 years will pass for those on earth (extrapolate the results of atomic clock and gps satelite). Another thing that interferes with time, is gravity. Since space and time are single fabric if you call it that, gravity will warp that fabric. In the extremes time will stop, if you where to orbit a singularity.

Now the mathematics and experiments PROVE that one can move forwards in time, but the mathematics allow the reverse, to travel back in time. This however has not been validated practically, but the mathematics provides the existance of wormholes (google it) which theoretically permit travel into the past. Therefore is time travel (for the future) possible? definately... though we will never achieve it. Since its improbable to power a craft of any kind to the speed of light, the second alternative is to ride gravitational energy. unfortunately, human beings wont live long enough to get to the closest source strong enough to do this, the galatic core (super massive blackhole). Even by some miracle you can get there, the radiation will kill you or the gravity influence will be so strong it will pull your blood to one side and you will die (just like if you stood on something the size of the sun you will die instantly). So thought its possible, it wont happen. Einstein said the future is merely an illusion, the past present and future exist simultaneously.

Personally, time travel will never happen. We cant create anything to move fast enough to go to the future, and traveling backwards is impossible why? cause I have not met a tourist from the future yet, and if what the mathematics say is true (i.e past present future exist at the same time) then that would mean no one has invented a means to travel BACK in time in the entire future per say. lol

 

[BandwidthAddict]

FTL will be discovered in South Africa, I'm convinced. Possibly in a taxi. Nowhere else are so many laws disregarded so quickly, why should physics be any different?

Lol. Seriously, rolling in the aisles.

 

[jeccyka]

Recently, i am reading a novel about time travelling,I love the novel's plot and characters, as if myself were in ancient times. Some people say"sometimes, would rather live in the ancient than modern", according to me, this is negative attitude,and i will ignore.

 

[Swa]

Lol. Seriously, rolling in the aisles.

http://www.hayibo.com/faster-than-l...mac-maharaj-as-anc-turns-back-clock-to-1980s/

 

[nogard]

This was proven using an atomic clock, 2 clocks perfectly in sync one went for a plane ride the other sat still. The clock on the plane had a time that was slower than the stationary one, thus it proved in motion its time slowed down.

Do you have links?

 

[Geriatrix]

Do you have links?

http://en.wikipedia.org/wiki/Time_dilation#Experimental_confirmation

 

[Techne]

I watched a movie a while ago called Primer and while it addressed some fascinating time travel concepts the whole idea of going back in time is totally impossible,even on a theoretical level.Here's why.

In movie's when people go back in time they encounter alternate versions of themselves.How is this possible when only ONE version of you exists.
If you're talking alternate universes then you cannot meet your other self if you do go back in time since you both exist in separate realities.

Primer tries to address this making sure your real self and your alternate self do not meet so as not to alter reality, but still this is completely implausable.

Any ideas?

I think time-travel depends on the relationship between the concept of time and the concept of change. For example:

A) Time exist as a result of or is a function of change. Time is an intellectual abstraction and a mathematical expression to quantify change. Without change there is no time sort of like without mass there is no gravity.
Or…
B) Time exists as some distinct (absolute or relative) entity and/or quantity and/or dimension that is different or distinct from the process of change. Time exists as an entity and/or quantity and/or dimension irrespective of whether there are things that are changing or not.

Newtonian physics assume time to be some sort of separate absolute quantity. In Minkowski space time is treated as a separate dimension and added to spacial dimensions to form the space-time manifold and the mathematical setting of Minkowski space is the setting in which Einstein developed his theory of special relativity. So it would seem that the mathematical model of space-time is compatible with B) as it treats time as some sort of dimension.

Historically though, time has always been measured as a function of some or other entity that is changing. For example, time was measured according to the rotation (note change of position of masses) of the earth around the sun (Ephemeris time) or atomic clocks (cycles of radiation corresponding to the transition - note change) between two energy levels of an atom) etc. But this duration of a second (in fact any second) is only relative, there is no absolute duration of a second and this is because of special and general relativity.

Looking at special relativity, time will appear to pass slower on objects (including atomic clocks) that are moving (changing) quicker relative to an object that is moving (changing) slower. That is why if an atomic clock can travel close to the speed of light for long periods of time, the atomic clock will appear to slow down, meaning the cycles of radiation corresponding to the transition (note change) between two energy levels of an atom will slow down relatively to other slower moving atomic clocks.

Also, looking at general relativity, time will appear to pass slower on atomic clocks closer to objects of greater mass compared to atomic clocks further away from objects with the same mass . That is why time "slows down" near a black hole. Here, again, a change in mass has an effect on the duration of change. Change thus is relative.

Thus, it would seem that the view that A) Time exist as a result of or is a function of change is not necessarily incompatible with special and general relativity and as some would argue "corresponds more adequately to the physical world". Work is being done to demonstrate the mathematics and physics behind this idea.

Scientists suggest spacetime has no time dimension

Replacing time with numerical order of material change resolves Zeno problems of motion

So if option A is correct then you would literally have to reverse all the changes in the universe to go back in time.

If option B is correct and time really is some sort of distinct quantity or dimension that is distinct from the process of change then I suppose one has to find a way to access this dimension and then travel within it. Option B though runs into a number paradoxes like the one you refer to in your OP.

 

[Geriatrix]

My head hurts.