Anti-gravity

[tommac]

Are there any theories or suggestions that there is a force that warps space-time in the opposite way that gravity does?

From my amature understanding of things gravity tends to legnthen space and slow time.

Are there any theories where "something" compresses space and speeds time?

How about travel near the speed of light?

I was thinking about this with regards to the expansion metric of the universe.

could the universe be expanding based only on the increase of gravity or antigravity ( as I am describing above )?

[a1call]

Bump.

Very good question.

Another way of asking the same thing would be:

*- What is the opposite of time dilation if any?

Added:
Google seems to know of no such theories, Just Sci-fi:

Time-compression; the opposite of time-dilation. Feels no faster, but looks FTL. Cancels out with the above if you try to combine the two.

Source

[m1omg]

Dark energy?

[astromark]

Dark energy?

and thats the problem.. We do not know what it is. 'Dark Energy' = ' Forces Unknown.'

It may not negate gravity. It might just be a stronger force.

Time would just soldier on regardless. It does not care what direction you go.

[tommac]

Time would just soldier on regardless. It does not care what direction you go.

Soldier on relative to what?

[Neverfly]

Soldier on relative to what?

Doesn't matter. Time is like a number. An assignment we gave to a perception. It is not a physical object.

[Trocisp]

Time is just a distance.

You can go left, right, forward, backwards, up, down... you're still moving.

[tommac]

Time is just a distance.

You can go left, right, forward, backwards, up, down... you're still moving.

how can you go right? I thought time was 1 dimentional.

[Neverfly]

Time is just a distance.

You can go left, right, forward, backwards, up, down... you're still moving.

Not really.
A distance describes the physical still.

Time does not. It describes an affect. Nothing more.

[John Mendenhall]

Not really.
A distance describes the physical still.

Time does not. It describes an affect. Nothing more.

I have to look this one up. I think distance between 2 events is x^2 + y^2 + z^2 - t^2, but I forget the units.

[Neverfly]

I have to look this one up. I think distance between 2 events is x^2 + y^2 + z^2 - t^2, but I forget the units.

Time- is a word.
It represents, even mathematically, our percpeption- but it does not represent the physical.

Distance does represent the physical.

Time does not.

[astromark]

Well done, Neverfly. Like a voice across the darkened room...
Time is not a distance,
or a direction,
or anything other than...
Just our perception of;... Relative measurement of interval between occurrences.= TIME.

[loglo]

Well done, Neverfly. Like a voice across the darkened room...
Time is not a distance,
or a direction,
or anything other than...
Just our perception of;... Relative measurement of interval between occurrences.= TIME.

Except that it goes against relativity! What was the point in unifying spacetime if time hasn't a distance measure? (I actually prefer to say that space has a time measure, but that just me.) I guess I'll just go and cross out all the "lightyears" in my text books now.

[astromark]

No.. You are assuming light speed in a year is some thing other than a distance. I ask you...'What is a light year?'

[mugaliens]

Well done, Neverfly. Like a voice across the darkened room...
Time is not a distance,
or a direction,
or anything other than...
Just our perception of;... Relative measurement of interval between occurrences.= TIME.

I disagree. From the photon's perspective, there is no time. Only distance. For all sub-lightspeed events, time and distance are inextricably connected via relativistic equations.

[loglo]

what is a light year?..a distance but since distance is defined by light travel time what is the difference?

[tommac]

Well done, Neverfly. Like a voice across the darkened room...
Time is not a distance,
or a direction,
or anything other than...
Just our perception of;... Relative measurement of interval between occurrences.= TIME.

Ummm ... I disagree.
I understand time to be part of space-time, which is a system of coordinates.
Now maybe you are thinking about a duration of time. Which is similar to distance along the t coordinate system.

[Neverfly]

what is a light year?..a distance but since distance is defined by light travel time what is the difference?

That is just the assignment we gave the distance.

We could have called light years "Starhops" or FarfromEarths" or uh..."parsecs..." or something...

That is a representation. It doesn't make time a physical thing or a description of the physical.

Originally Posted by Mugaliens:
I disagree. From the photon's perspective, there is no time. Only distance. For all sub-lightspeed events, time and distance are inextricably connected via relativistic equations.

According to mathematics- Yes. It describes the relationships. But that does not mean that it describes the PHYSICAL relationship of TIME nor that Time is a description of physical representation.
Time is an effect.

[Neverfly]

Ummm ... I disagree.
I understand time to be part of space-time, which is a system of coordinates.
Now maybe you are thinking about a duration of time. Which is similar to distance along the t coordinate system.

It doesn't matter what it looks like when you graph it out.

It's the measurement of effect- not the measurement of physical nature.

[Trocisp]

Time is a measure of distance. how do you know ?

Because two points in time are separated by a specific amount of time in between.

Very simple.

[Neverfly]

Time is a measure of distance. how do you know ?

Because two points in time are separated by a specific amount of time in between.

Very simple.

No.

If you are utterly motionless. If you get off the galaxy and sit unmoving, time will proceed at the same rate (To time, to you, that rate will appear the same, to an outside observer, time will appear to move a bit faster for you).

Time is a word we use to describe the flow of an effect.

[trinitree88]

Time- is a word.
It represents, even mathematically, our percpeption- but it does not represent the physical.

Distance does represent the physical.

Time does not.

Neverfly. I disagree.
The arrow of time moves inexorably towards the increase of entropy in the universe. More disorder is coming. Of that we are certain, otherwise we abandon thermodynamics, and making any sense of the universe is a fruitless excercise. Our hierarchy of conservation laws contains a half dozen that are seen to be consistently inviolate. pete

[Neverfly]

Neverfly. I disagree.
The arrow of time moves inexorably towards the increase of entropy in the universe. More disorder is coming. Of that we are certain, otherwise we abandon thermodynamics, and making any sense of the universe is a fruitless excercise. Our hierarchy of conservation laws contains a half dozen that are seen to be consistently inviolate. pete

I do understand exactly where you are coming from- and I understand the role that time plays in the equations...

But...

What I am saying is that time is a representation of the flow. In the same manner that you just described.
Time is "real" in the sense that the effect is real.
But time itself is not a fancy sci fi type THING nor is it like distance. It plots on a graph like distance- but it is not a distance.

Now, if more SR and GR smarts come in too, and persist in telling me I have misunderstood a fundamental concept of time- I will start to listen. And I will look into it.

But as it stands, my understanding of time is that it is not physical- it is an effect. One we can measure (With our inventions), one that can appear to be dilated- but it is a reference- nothing more.

[cosmocrazy]

Are there any theories or suggestions that there is a force that warps space-time in the opposite way that gravity does?

From my armature understanding of things gravity tends to lengthen space and slow time.

Are there any theories where "something" compresses space and speeds time?

How about travel near the speed of light?

I was thinking about this with regards to the expansion metric of the universe.

could the universe be expanding based only on the increase of gravity or anti gravity ( as I am describing above )?

Going back to the OP.
Based on the theory of gravity being the effect of mass warping space-time using the simple analogy we are all aware of. A heavy ball is placed on a stretched out piece of rubber sheet and another ball in motion is trapped in orbit around it due to the warping of the sheet. If we think of the space-time fabric in this way, as being a flat stretched out sheet and all mass in our universe is warping this sheet as in the rubber sheet analogy. Then how about (in really simplistic terms), mass on the "other side" of this sheet warping it the opposite way? creating an anti gravity effect.
If instead we consider gravity to be a force, then maybe we can define it somehow as, say - the exchange of gravitons between matter/energy? if this is the case then perhaps there are 2 types of "charge" of a graviton + & - ?

[Neverfly]

The rubber sheet analogy is a simplified analogy. But it is not a true representation of the Warping of space.

As long as something has mass, it will have gravity as we know gravity to behave. There is no "other side of the rubber sheet."

Think of a Black Hole. Light cannot escape.
Yet light has no mass- so why is it affected by gravity?
Because gravity has warped the space to such a high degree that light cannot leave even though it is traveling at 300,000 km per second- in a straight line.
The space is so warped that all straight lines lead back inside.

Try that with a rubber sheet.

[cosmocrazy]

The rubber sheet analogy is a simplified analogy. But it is not a true representation of the Warping of space.

As long as something has mass, it will have gravity as we know gravity to behave. There is no "other side of the rubber sheet."

Think of a Black Hole. Light cannot escape.
Yet light has no mass- so why is it affected by gravity?
Because gravity has warped the space to such a high degree that light cannot leave even though it is traveling at 300,000 km per second- in a straight line.
The space is so warped that all straight lines lead back inside.

Try that with a rubber sheet.

I am aware of the rubber sheet analogy to be a simplistic view of the warping of space- time.
The term "gravity" in this theory is the effect of mass on space-time. If you take the simple sheet analogy, a mass large enough warps the sheet so much it could even puncture a hole through in which everything "falls in" (worm hole maybe?). Using the sheet analogy, there are theories about the universe being one of countless membranes, from this point of view there could be "another side". I,m just suggesting simple hypothetical possibilities for the question about anti matter.

[cosmocrazy]

I,m just suggesting simple hypothetical possibilities for the question about anti matter.

Sorry ment to say Anti Gravity da!

[trinitree88]

I do understand exactly where you are coming from- and I understand the role that time plays in the equations...

But...

What I am saying is that time is a representation of the flow. In the same manner that you just described.
Time is "real" in the sense that the effect is real.
But time itself is not a fancy sci fi type THING nor is it like distance. It plots on a graph like distance- but it is not a distance.

Now, if more SR and GR smarts come in too, and persist in telling me I have misunderstood a fundamental concept of time- I will start to listen. And I will look into it.

But as it stands, my understanding of time is that it is not physical- it is an effect. One we can measure (With our inventions), one that can appear to be dilated- but it is a reference- nothing more.

Neverfly. Semantics. Fair enough. pete

[Neverfly]

Neverfly. Semantics. Fair enough. pete

Trinitree- in this particular case, I have pushed the point because the background wants to turn time into something like a rope- that can be twisted back upon itself- leading to speculations about time travel, time loops, open and closed loops- etc, all of which have no standing in the observational universe.

Sometimes, you can demonstrate these things mathematically, however- that does not mean these things can actually be done anymore than that a white hole can exist. Additional mathematics also usually prevents time loops.

[Trocisp]

No.

If you are utterly motionless. If you get off the galaxy and sit unmoving, time will proceed at the same rate (To time, to you, that rate will appear the same, to an outside observer, time will appear to move a bit faster for you).

Time is a word we use to describe the flow of an effect.

I never said that the same time was everywhere.

I simply said that time is a distance.

If I were utterly motionless, I would just be moving a bit faster (distance wise) than the outside observer.

I understand physics, neverfly. I am not a moron. There is no need to talk down to me.


You, my friend, are the one who doesn't understand me. I understand you perfectly well. I just think you're wrong.