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The problem with time machines, is when they start.

by Redhats Q / May 3, 2006 8:07 AM PDT

Sorry Molly, But time travel is actually quite simple but it has some limits that make it easy to see why we don't have them yet.

We know how to go forward in time and thanks to relativity we can speed that up and slip into the future.

Its getting back thats hard. No mass can go backwards due to relativity, to go backwards you go faster than light and since no object with mass can exceed the speed of light people cant go backwards.

However some particles can cheat, especially light.

Imagine a cup of coffee , stir it, Drop in a coffee bean relative to the coffee the bean is almost stationary, but relative to us the bean is moving.

When light travels through space it actually causes space to move just a little. High power lasers carefully aimed, can create a spinning bit of space and when Light is fired into the space it moves at the speed of light + the speed of the space. This is to us faster than the speed of light and so the light moves backwards in time.

Since Light can carry information it can be used to send a message back in time. This message tunnels backwards in time until the space stops spinnig. or the point at which the machine is turned on.

In short Time travel will not be possible until the first machine is turned on, at which point it should start dumping information and messages from the future which will be sent to it later.

To move a person you need a transporter at each end and just send the data between them. But then is that the same person .. blah blah blah.

I tried to make it simple but in essence Until the machine is turned on there is nothing to travel back to, and no way to go any earlier.

So until they make it, it can be used to come back to.

At least not with any physics we understand.

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This is so kool
by wizardjs / May 3, 2006 8:11 AM PDT

Sorry, just remembering something about a show where some guy was saying the same thing. Aweasome to know he's not the only one. He was designing a mchine using this principle, I don't konw how that's going, it was a while ago, but for the life of me I can't remember his name. It was Ron something......

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Yep I did a paper on his work
by Redhats Q / May 3, 2006 9:39 AM PDT
In reply to: This is so kool

Its very cool, but there are some issues with that too

Like all time travel, we cant do it, But there maigh be ways to cheat

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Oops forgot to add the Name Ronald L Mallett
by Redhats Q / May 3, 2006 12:33 PM PDT
In reply to: This is so kool

This is the man making the time machine

He's at the university of Connecticut

Ronald Mallett



Title
PROFESSOR

Department
PHYSICS

Status
Faculty

Building
PHYSICS BLDG

UBox
UNIT 3046

E-mail
Ron.Mallett@uconn.edu

But the real pioneer work belongs to

Proffessor Kip Thorne who realised that if you made a wormhole and sent one end on a trip (so time passed more slowly, and the other stayed still that there would be a temporal difference between the 2 ends.

Literally a tunnel in time.

Of course wormholes are a whole new topic but the negative energy they need is being made in seattle by Steve Lamoreaux's team so the area is no longer just science fiction.

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(NT) (NT) Thx, that was it
by wizardjs / May 4, 2006 6:05 AM PDT
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Something about that argument always bugs me

That is a very well-respected explanation and you did a damn fine job explaining it Redhats.


However something has always bugged me about it. The word 'until'. Until means at a certain point in time. But if you consider time a dimension that exists forward and backward and you can travel through it, how is it that we have to wait until we subjectively experience a certain moment before the information starts getting dumpoed back here?

In other words if at some point in the futre someone will dump information backwards, why don't we see that info now? Just because we subjectively are experienceing now, now? That seems anthrocentric. Or at least Chonocentric. Our time is the only one that maters.

You getting me?

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Sure do
by Redhats Q / May 3, 2006 10:04 AM PDT

Its a physics limit .. at least for now.

If time really is a dimension we can travel in then it would be easy to affect anything. BUT its not so easy, esp with the techinique I am discussing.

Consider a 2 dimensioal life form living on an a4 piece of photocopy paper. Every day he walks arround on the paper until a line is drawn dividing it in half.

For Him Half the world Vanished. The line is an impassable barrier. He cannot consider the third dimension, and even if he did he could not move in it to help him.

If time is to be a fourth dimension (IF) then to travel in time is to operate outside the world in which you are made, You could never be aware of it. Yet we experience and are aware of Time and its passing. SO I find the whole dimension concept flawed.

I don't consider Time a dimension, Rather Time and Space are linked with the basic concept that distance=speed x Time so time is a byproduct of space.

Prior to space there could be no time. The only method we know that would allow time to move in a reverse direction is by relativity and that imposes a limit that space must be spinning for it to work.

It may be possible that such an event exists in the cosmos arround a black hole in which case at the beginning (moment of creation) of the black hole there would be a white hole in which the all the light that is ever captured by the black hole would be released as energy at that single moment in time.

We have not yet observed such an event! But imagine the amount of energy that such an event would release.

If this does however exist .. we have the math for a wormhole that moves in time and space (space being how far the black hole has travelled in its life) and time being the age of the black hole.

Back to our machine: The reason we cant see it now is that the moment the space stops spinning the photon drops to normal light speed and can not travel any further backwards so there is a limit to how far back in time you can go with this method. And there doesn't yet seem to be any way to get of it the middle of the ride. Once you get on you are committed.

Again at least not with our current physics. But smarter minds than mine may yet find a way

And NO !!! I am not going into string theory which is Just Plain Nuts (and it makes pain in headmeat place where thinks come from) (I Love Dave the Barbarian)

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your assertion that time is a byproduct of space
by cardsbb9 / May 3, 2006 10:38 AM PDT
In reply to: Sure do

your assertion that Time is a by-product of Space seems to be based on a formal abstraction of the observable. However, because of Godel's incompleteness theorem, I hold that the only true way to understand Time is to be a being that transcends Time. As we are all subject to Time we cannot observe the complete aspects of Time that would allow us to fully understand it. Therefor I hold that (absent objective proof to the contrary, or reliable testimony from an transcendent being) that it is possible for time to exist absent space or matter.

"There are more things in heaven and earth, Horatio, Than are dreamt of in your philosophy." - or another way to say it - Just because you cannot see it does not mean it is not there.

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Such a vist would be very welcome
by Redhats Q / May 3, 2006 10:47 AM PDT

Hey Cool, If God feels like poping in for a coffee and want to explain time to me, I would be over the moon and would welcome the definative answer

Until then I will have to struggle on based on the laws of physics.

And no disrepect to any divine Beings intended

I am after all a Q ... or did you miss that ???

Yep its hard to understand, But I have issues with time as a dimension. I don't think its very helpful. Your commenst fit really well with the poor creature on his piece of paper.

Will someone please rub out the line and give Him his world back.

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Is an explaination sufficient?
by cardsbb9 / May 3, 2006 11:13 AM PDT

My perspective that all means of communication available wouldn't be sufficient to communicate all aspects of Time to you until and unless by visiting God also made you transcendent to Time as well.

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perhaps there are some of us who have 'the line rubbed out'
by cardsbb9 / May 3, 2006 11:42 AM PDT

if there were some of us who had been made transcendent enough by a divine intervention would we believe what they had to say to us?

Could we even have sufficient objective proof (for us who are not transcendent) that the transcendent ones are in fact transcendent?

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OK
by acedtect-20196213851867054973637995818137 / May 5, 2006 4:10 AM PDT
In reply to: Sure do

Good explanation. But when you say relativity for the photon traveling, I'm confused. The other time-travel method I'm familiar with is Feynman diagrams in Quantum Electrodynamics where the diagrams can only balance if an electron moves bacward in time. Are you speaking of the same thing?

Anyway that's irrelevant to your point I think, which is that you can't get on the ride mid-way. So I think this fits in quite nicely with the thought experiment that we cna only travel backward in time to the point where the first time machine was invented. For whatever reason.

Aside from dismissing time as a dimension, it's also quite possible it may not exist at all but is merely a perception artifact. I've heard this theory purported too. The big oversimplification is that everything already exists and our experience of time is just the way our brain processes it sensory input and organises it for our viewiing pleasure. Kind of like BitTorrent for reality.

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From what I know...... entropy.....
by cardsbb9 / May 3, 2006 10:25 AM PDT

From the little I understand about this .... Entropy is what makes the direction of time 'flow forward'.

So, to prevent the entropy of the whole universe from 'cannibalizing' your information stream you have to direct that stream at a specific 'target'. That 'target' would be a mechanism for receiving information sent to it through 'the fourth dimension'. As that machine (to the best of our knowledge) does not 'exist yet' (and as our existence is confined to a single moment in time) then we have no way of receiving any time-traveling information.

To draw an over-simplistic analogy.... if 'the professor' on Gilligans Island hasn't (yet) fixed the radio to receive a GPS signal then no one on the island would be able to use the GPS signal to know where they are, regardless of the fact that the GPS signal is constantly being 'sent to them'.

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Scrolls
by MacHugger / May 3, 2006 10:39 AM PDT

I too have a problem with the concept of time being a dimension that you can move around in. I never really considered the relativistic hop into the future to be time travel. It's more like a cheat of the system and comes around more to what Redhats was saying about time being a by-product of space as movement occurs in it (distance is generated over... time).

In the same way that you can beat your brother in a race to grandma's house by cutting through the neighbor's yard and jumping fences while he takes the sidewalks, you can cut through time by approaching the speed of light. But once having made it to grandma's house, you can't undo having been there - you just got there faster. This is a weak analogy, of course, but it helps me a little to think it through.

For time to be a dimension, it would say that the entire universe of happenings already exists and we are merely playing our way through it like the scroll on an old fashioned player piano that already has the entire tune embedded in it. Play it forward, play it backward, the entire tune is already there. Is the universe's past, present and future already carved on a scroll? I have to think not.

-Kevin S.

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CS lewis
by Redhats Q / May 3, 2006 10:57 AM PDT
In reply to: Scrolls

Yep CS Lewis (Narnia) also looked at time like this, His traveller saw the future as all Ghosts with whom he could not interact, and the past as so solid that even a blade of grass was unmovable and cut you to shreds.

I even read one story of such a traveller who fell from the view platform, Got sliced up by the Grass and managed to drag himself onto the platform, "Just as the first drops of rain began to fall.


OUCH

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to account for Chaos Theory.....
by cardsbb9 / May 3, 2006 11:26 AM PDT
In reply to: CS lewis

The very air molecules themselves would have to be immobile otherwise we would have a situation like 'the butterfly effect'.

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Never let Science get in the way of Science Fiction
by Redhats Q / May 3, 2006 11:30 AM PDT

Yep.

But it was a very cool short story

HOLES and all

Ever read bout the guy who drove his way back like a wedge, Then discovered how hard it was to get the wedge back out after you drove it in.

Why is it that I work around scientists, and they all read Science Fiction. There's more SCI-FI here than the Public Library.

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Determinism
by cardsbb9 / May 3, 2006 11:21 AM PDT
In reply to: Scrolls

I knew we would have to get to determinism in this kind of discussion!

I, also, am a holder of non-determinism.

However I do hold that time is a dimension.

Next.... we will have to get into our perception of existence (both ours and the existence of everything else in the observable universe).

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Indeterminate determinism
by acedtect-20196213851867054973637995818137 / May 5, 2006 4:14 AM PDT
In reply to: Determinism

All of time can exist but still not be determinate if you understand anything about quantum mechanics.

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Just Q
by Redhats Q / May 3, 2006 11:25 AM PDT

Its just Q

Redhat is to do with where I work.

Q is what/Who I am

You decide if the the James Bond one, The Star Trek One or the Bible Study Theological One. ( I only know of these 3, but there could be more)

But It's Q

Just

Q

Pronounced Q or Que or Cue but never q

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I was thinking...
by RodderRodder / May 3, 2006 12:23 PM PDT
In reply to: Just Q

Wormhole alien (or prophet or Bajor). Either way, possible Subbrillient blog candidate.... And smarter than the average Bear.

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What me .. no WAY !!!
by Redhats Q / May 3, 2006 12:41 PM PDT
In reply to: I was thinking...

Theoretical Physics is a hobby. brought on by reading (and writing) too much science fiction.

My passion is Genetics, As a IT person I am interested in working out the code languages, so that more efficient programming structures can be analysed.

IF risc is cool, think about genome in which only 4 simple structures (we call them A C G & T) are the whole language Instructions the operators and operands are all in a code so simple and yet so complex that it makes every living thing on the planet.

And uses only four simple structures.

Care to write computer code using only combinations of 4 letters.

NOW THAT ROCKS !!!!!!!!!

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but machine language is done only with two symbols
by cardsbb9 / May 3, 2006 12:50 PM PDT
In reply to: What me .. no WAY !!!

yeah, I am referring to binary..... which is kind of 'cheating' as the real unit of construction is the byte which (on 8 bit machines) has 256 different values to work with.

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And there is the problem
by Redhats Q / May 3, 2006 1:00 PM PDT

There is no such code in the genome.

Thats what we were expecting, but the human genome project showed us that that is not the case. so know we have to work so much harder to decode the way it works..

Its amazing to see how many things change when you change one simple marker

Its sort of like 3D Chess. Or worse a sort of 4D soduku

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I sm a potential benefactor of your work
by cardsbb9 / May 3, 2006 1:41 PM PDT
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Sorry to hear it.
by Redhats Q / May 3, 2006 2:09 PM PDT

I'll put in extra effort to make sure the research boys get the cleanest possible results from the runtimes.

Maybe well get lucky and hit some usefull data

For your sake I hope so

Thats the good part of this job, Its doing something worthwhile so much of the time (not always) but often.

Take Care

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64 bit computing is ...
by Redhats Q / May 3, 2006 1:08 PM PDT

lots anyway

he he

Were way past 8 bit languages

Now instead of squaring or Cubing .. To the power of 4

Owwwwiie - Hurting my head meat again !!!!!!

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Its all back to relativity
by Redhats Q / May 3, 2006 2:04 PM PDT

Einstien would have loved this discussion

If time and Space are linked. (and they are) and time is observable, then its all about relativity. Our perception of Time and Space is relative to a single point. Namely Me. In all time and all space the location of the observer is the key to all that happens.

If I go faster than Light You age, But If you go faster than light instead, then You dont age.

The observer is everything


"Time is an illusion, Lunch time Doubly so." Ford Prefect - HitchHikers Guide to the Galaxy

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gaining another perspective
by cardsbb9 / May 3, 2006 2:48 PM PDT

Ah, but if we were beneficially made more transcendent (perhaps by some deity) then we would have the potential ability to observe the universe from some other point than ourselves.

But then we would never be able to prove beyond an absolute doubt that we were made more transcendent.

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And its still you perspective
by Redhats Q / May 3, 2006 3:17 PM PDT

Even If I clicked my fingers and sent you there, You would still only see according to your perspective.

It's a limit of perspective. Try as we might we are stuck in a small mental box of what we can understand.

Outside that there lies a whole new level of truth we will never comprehend.

No Matter how much you know you can never know it all.

Thats why we can NEVER make a definate absolute negative statement.

For example to say there is no Gold in the Cnet Building I need to know everything about the CNET building. right down to what filings is in everyones mouth, But to say there is Gold in the Cnet building, I need only see one bit of Gold in a bit of jewelery on the finger or neck of one host to say its there.

Thats why scientists should be careful when they say something is impossible. Better to say it seems impossible with the laws of Physics as we understand them.

Just because we don't see how to do it, Doesn't mean it cant be done.

Of course its always possible that its impossible, and we dont realise that yet.


And we thought Time paradoxes were hard to understand .....

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Everything is probability

When you drill down far enough it's impossible to say what's there and what isn't. It's all a matter of probability. This isn't a nihilist hypothesis it's just Quantum. The aggregate of all those probabilities makes for a very solid world with fairly solid facts. But it's all built on particles that pop in and out of existence.

It's like a ball resting on a gust of air in a way. The ball can stay relatively still even though the air is constantly moving and changing.

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