[DivineThought]

Note* This is my first post to a forum consisting of intelligent individuals, so please excuse any commonality.

It begun like this.

A friend and I were in my room watching a film when I got a sudden feel of sadness knowing that I would most likely never be able to back in time. I told him that one day, I was at least going to be even a small help to the discovery of time travel into the past. I looked towards the future, however not far into it, only a few seconds, and decided that every time we are moving, we are moving into the future, and that is fact.

I then realized that there must be an opposite to speed. My friend said slow, but of course he did not understand that I meant speed in general. He later said reverse, but again, reserve, is just a speed in the other direction, no matter how fast or slow it is, in any direction, it's still speed, and you are still moving towards the future.

I thought that being still, may have been acceptable, however the earth still spins no matter if you are standing still or are moving. Even then, the sun spins around the center of the milky way, which we are spinning around also, which is probably also spinning around something else.

But even if we could stand still, or be completely still, outside of any gravitational force, that is still not the opposite of speed. It's like 'neutral' in a car, or 'maybe' in an answer.

So...

Do you think there is, or could be an opposite of speed, I mean if you think about it, there has to be, the only problem is that it may be one of those unthinkable answers, waiting to be discovered.

The idea being that if we found the opposite to speed, since speed moves us into the future, the opposite would move us back into the past.

Therefore, time travel to the past?

Note* I know that something similar to this has been posted on the forum, because I searched before I posted, however it wasn't getting to the same point I have in my mind. So I posted anyway.

This post has been edited by DivineThought: 12 August 2012 - 07:17 PM

[Pincho Paxton]

If you really want to study time you should learn about physics. You could also look at some African tribes out in the jungle, they have different versions of time to ourselves. The more intelligent you become, the easier it is to answer, but when you do know the answer to time, you find that you are not allowed to answer such questions, because science will not accept your answer. I suggest you study nuclear clocks, and time displacement. You can figure it out from that.

[CraigD]

Welcome to hypography, DivineThought. I hope we can help with what you’re looking for. If you’d like, start a topic in the introductions forum to tell us something about yourself.

DivineThought, on 12 August 2012 - 07:10 PM, said:

Do you think there is, or could be an opposite of speed, I mean if you think about it, there has to be, the only problem is that it may be one of those unthinkable answers, waiting to be discovered.

You’ve got to be careful with language like this, because just because a word exists and corresponds to a mental impression, there’s no guarantee these correspond to a real, physical object or event, or have an opposite. Being unaware of this bit of philosopy leads to the fallacy know as reification, or “the map is not the territory”.

There are several physical plausible schemes for sending yourself into the past (in scientific language, following a closed time-like curve (CTC)), falling into 3 main categories:

• Ones that require traveling faster than the speed of light (FTL) (here is a wonderfully illustrated explanation of a scheme of this kind)
  
• Ones involving the gravity of very massive objects (eg a Tipler cylinder)
  
• Ones involving “exotic matter” with negative mass to create wormholes (Kip Thorne has described these - start here for more)

All these schemes appear to require more advanced engineering abilities than we humans currently have, and it’s uncertain if any are actually possible.

My personal hunch is that some sort of CTC is possible via FTL signaling, but that it will be very difficult, even after centuries of scientific and technological advances, to use the effect to send an object or signal of any kind more than a short duration into the past.

Pincho Paxton, on 13 August 2012 - 03:53 AM, said:

If you really want to study time you should learn about physics.

I agree with Pincho. You can never learn too much physics.

[SaxonViolence]

I'm far from expert...

However Science and Physics in particular uses words in ways that are not quite identical to their everyday use.

"Work" is an example.

In Physics the word "Work" means that you're moving something...

Whereas in ordinary parlance we often use the word "Work" to mean that something is Tedious or Unpleasant.

The Science teacher tells his students that holding a heavy weight overhead, or frantically trying to push a wall down entails no Work ₁, because nothing ends up getting moved.

An irritated student says, "I'll make you hold a 100 pound Barbell overhead all day. When I come Back, tell me that it wasn't Work₂ !!!"

They're talking about two different things.

Time, the Physicists believe, is a Fourth Spatial Dimension--but many of their descriptions are difficult to acquire, especially without a sound grasp of Mathematics.

I'm not sure what you mean by negative speed. I can tell you that all motion is relative to a given reference frame.

Given the right reference frame, anything can be thought of as motionless.

Some frames of reference are dramatically simpler than others.

The ancients believed that the Earth sat still and the stars and planets revolved around us.

Trouble was, some planetary motions (what is called "retrograde motion") is very hard to account for by picturing each planet imbedded in a single crystal sphere.

Crystal Spheres imbedded in still other crystal spheres was tried. That helped, but it wasn't quite enough.

If I remember correctly, they were up to almost 200 interlocked crystal spheres and still hadn't gotten it quite right, when the heliocentric solar system came to be widely accepted.

The heliocentric solar system accounts for retrograde motion very simply...

However, so much work had gone into the system of Crystal Spheres, that even though no one really believed in them anymore, they were still the best and most accurate way to project planetary motions for generations afterward.

Relativity says that it's not a question of who is moving and who is still...

It is a question of which coordinate system is the simplest to use.

The Japanese have a word "Mu", that means literally "Un-ask the question" or "The question is nonsensical in the context you frame it in."

A western lawyer would use the phrase: "Assumes facts not in evidence."

I think that your negative speed fits into that category...

And if I'm wrong, you'll still have to learn to phrase your question better--probably in terms of mathematics--before any scientists will pay any heed.

I take this much time, because those are the type questions that hung me up for long whiles, because they weren't explained very well.

Saxon Violence

[JMJones0424]

SaxonViolence, on 13 August 2012 - 08:24 AM, said:

Time, the Physicists believe, is a Fourth Spatial Dimension--but many of their descriptions are difficult to acquire, especially without a sound grasp of Mathematics.

It's not accurate to say that physicists believe time to be a fourth spatial dimension. There are only three observed spatial dimensions. It is useful to consider time being a fourth dimension because it is useful to arrange the time that events occur on a number line, and in order to have a universally acceptable frame of reference in which to describe an event, you must include the time at which you observe the event as well as the location in three spatial dimensions that you observe the event. A dimension, in this case, is the magnitude of a measurement that can be arranged on a number line.

[sigurdV]

Hi all! (and especially you mr Jones)

Speed is a tricky concept : suppose your absolutely (no predefinition of that concept today folks) still, then your speed in time is at its highest! Now travel at the speed of light (just a thought experiment) and your speed through time is at its lowest...actually zero!

To be more technical: Measure the age of the universe,u1, at the time,t1, and repeat later to get u2 and t2 now compare (u2-u1) with (t2-t1)... discuss if (u2-u1) CAN be less than (t2-t1). And theres your answer!

Edit: Hi maddog

This post has been edited by sigurdV: 14 August 2012 - 03:29 PM

[maddog]

Divine Thought,

I will pose it this way. Often the word "speed" is thought of a Velocity without a direction in mind. So to consider a "negative speed" does imply some kind of direction that you have equated with time travel. Like SigurdV has said earlier, it looks like you have some definitions a bit scrambled for anyone to answer your question. I would break it down to what is the objective you are driving at. Is it Time Travel, if so I will have more to say on that tomorrow.

maddog

[ryan2006]

The opposite to speed is deacceleration and that is when time slows down if your going to time travel you can either accelerate or deaccelerate. Ryan

[Pincho Paxton]

ryan2006, on 14 August 2012 - 09:56 PM, said:

The opposite to speed is deacceleration and that is when time slows down if your going to time travel you can either accelerate or deaccelerate. Ryan

Speed is not acceleration.

[maddog]

ryan2006, on 14 August 2012 - 09:56 PM, said:

The opposite to speed is deacceleration and that is when time slows down if your going to time travel you can either accelerate or deaccelerate. Ryan

Yes, as Pincho said: Deceleration does not oppose "speed". Deceleration is the opposite of acceleration in general (think 2nd order derivative of distance traveled). In this way "speed" is the value of the Velocity (1st Order derivative) without a direction involved. Speed is just the value of Velocity. If it had an opposite it would be '0' or still as in not in motion relative to your reference frame.

So as I said yesterday, this is very different from traveling in time. Now truly we are all time traveling now. It is at the tick of clock while you are reading this post. Time is passing. If you were moving fast enough, your time would pass the same in your frame, though would be very different to someone who was still relative to you. To do as you claim have time reverse would involve something very different. One method by Kip Thorne of Cal Tech has proposed that time travel to the past could be possible to fall into a wormhole. This is an object like a Black Hole yet for some reason, the singularity at the center is not just a point but bigger in size though very small. So as you fall in there is an "other side" to get to. Thorne seems to think that the other side is not prohibited from being in this universe. It even be in our past. Now he may not be alone in thinking this way, though his opinion is not held with agreement by the collective of physicists today. Some think such a wormhole must end in another universe or because breaking causality it is prevented from existence. Stephen Hawking thinks this way. I personally have a relaxed view of causality. That is Causality need only locally upheld (that is inside the lightcone from the observer). So no event in spacetime that is beyond timelike (spacelike instead) requires Causality to hold. Such an event could not be the cause of another. So no "killing your grandmother" or some other kind of paradox.

maddog