Wouldn’t time dilation govern a speed limit?

[ynot]

This is perfectly correct. What's the problem?

As you say here, the acceleration slows down, and it slows in a way that causes the velocity to approach a limit. Since you won't allow math we can't show you what that limit is, but it should be intuitively obvious that it's c (since that's the point where the acceleration goes to zero).

As I understand it, “accelerating” is an increase in speed/velocity, and when a thing stops accelerating it is “accelerated” at a constant speed/velocity. In other words, it hasn’t stopped or slowed, it has just stopped increasing. “Accelerating” is increasing, “accelerated” is constant. Is this correct?

If so, I’m talking about time dilation slowing down and stopping “accelerating” only, not “accelerated“. In fact I don’t see how “accelerated” could be slowed or stopped by time dilation. If a thing has a constant speed/velocity, then the time dilation that affects it must also be constant.

I’m suggesting that the point where time dilation stops “accelerating” is the point where time dilation governs speed/velocity. As “accelerated” hasn’t been stopped, this point is less than c.

 

[Speed of Light]

No!

It would rob you of your acceleration. Speed, relative to a stationary observer, would be the speed of light, as stipulated. Speed, as observed by the traveller, would be infinite.

Everywhere at the same time

Infinite or zero - There is no difference!

Isn't 'Instantaneous' the most accurate description?

 

[ynot]

I’ve just realised that using a time dilated rocket thrust doesn’t give a valid example of what I’m meaning. For the thrust to reduce to zero it would require a speed of c. What I’m talking about is the very speed that an object is accelerating (increasing speed) away from a stationary observer being slowed by time dilation, regardless of how that increase in speed is generated.

 

[Reality Check]

There is no point in just talking about time dilation since there is also length dilation.

 

[ynot]

I guess what I’m asking about is speed/velocity dilation, regardless of what causes it.

PixiMisa earlier gave an analogy of a clock being filled with butter. Using the same analogy, I’m suggesting that the clock is moving through butter, and the faster the clock moves, the more the butter restricts its movement. Also that there is a point at which the clock can move through the butter but its speed can‘t be increased. In other words, the clock can increase its speed through the butter up to that point but not beyond it.

 

[PixyMisa]

As I understand it, “accelerating” is an increase in speed/velocity, and when a thing stops accelerating it is “accelerated” at a constant speed/velocity. In other words, it hasn’t stopped or slowed, it has just stopped increasing. “Accelerating” is increasing, “accelerated” is constant. Is this correct?

Acceleration is any change in speed or velocity.

Your use of "accelerated" here would be extremely confusing in almost any context; I've never seen anyone use the word like that.

If a thing has a constant speed/velocity, then the time dilation that affects it must also be constant.

Correct.

I’m suggesting that the point where time dilation stops “accelerating” is the point where time dilation governs speed/velocity.

Time dilation increases as a function of speed until you reach the speed of light, where it reaches infinity.

As “accelerated” hasn’t been stopped, this point is less than c.

Time dilation happens at any non-zero speed. The only speeds significant to the function are zero, where time dilation is zero, and the speed of light, where time dilation is infinite.

 

[ynot]

Acceleration is any change in speed or velocity.

Your use of "accelerated" here would be extremely confusing in almost any context; I've never seen anyone use the word like that.

So what's the correct term for a thing that isn't undergoing acceleration?

 

[PixyMisa]

You just say that it's moving at a constant speed (or velocity).

 

[Reality Check]

So what's the correct term for a thing that isn't undergoing acceleration?

A thing with "no acceleration" or "constant speed".

 

[ynot]

I was wrong when I earlier said - “The fast you go, the slower you go”. I should have said - “The faster you go, the less you are able to go faster”.

Time dilation is essentially speed dilation, and the greater the amount of speed the greater the amount of dilation. Any speed that is set and constant is only dilated by a set and constant amount and any increase in dilation is only created by an increase in speed. In other words, other than the “default” amount of dilation that any developed speed has, dilation only reduces the ability of that speed to increase. Theoretically it would be possible to reach a speed at which no increase in speed would be possible. The speed developed however would remain as a constant speed. This speed couldn‘t be the speed of light because speed stops at c.

Wacky thought - Perhaps speed doesn’t stop at c, but c is the speed at which an increase in speed isn’t possible. In other words, the speed of light has been governed to c by dilation.

Time for my medication

 

[Reality Check]

I was wrong when I earlier said - “The fast you go, the slower you go”. I should have said - “The faster you go, the less you are able to go faster”.

Time dilation is essentially speed dilation, and the greater the amount of speed the greater the amount of dilation. Any speed that is set and constant is only dilated by a set and constant amount and any increase in dilation is only created by an increase in speed. In other words, other than the “default” amount of dilation that any developed speed has, dilation only reduces the ability of that speed to increase. Theoretically it would be possible to reach a speed at which no increase in speed would be possible. The speed developed however would remain as a constant speed. This speed couldn‘t be the speed of light because speed stops at c.

Wacky thought - Perhaps speed doesn’t stop at c, but c is the speed at which an increase in speed isn’t possible. In other words, the speed of light has been governed to c by dilation.

Time for my medication

Still not quite right:
Speed does not stop at c. The speed of light is a limit to the possible speed of an object so the speed never reaches c.
So in your terminology: Time dilation means that there is a limit to the amount that you can increase speed and that limit goes to zero as you approach the speed of light. Your last sentence should read
"This speed is the speed of light because speed increase goes to zero as the speed approaches c".

Remember that time dilation includes the speed of light and so the speed of light is a built-in limit. This is because a posulate of Special Relativity is

The Principle of Invariant Light Speed - Light in vacuum propagates with the speed c (a fixed constant) in terms of any system of inertial coordinates, regardless of the state of motion of the light source.

 

[PixyMisa]

I was wrong when I earlier said - “The fast you go, the slower you go”. I should have said - “The faster you go, the less you are able to go faster”.

Right!

Time dilation is essentially speed dilation, and the greater the amount of speed the greater the amount of dilation.

Acceleration!!!!

Any speed that is set and constant is only dilated by a set and constant amount and any increase in dilation is only created by an increase in speed. In other words, other than the “default” amount of dilation that any developed speed has, dilation only reduces the ability of that speed to increase. Theoretically it would be possible to reach a speed at which no increase in speed would be possible. The speed developed however would remain as a constant speed. This speed couldn‘t be the speed of light because speed stops at c.

The limit is the speed of light. You can approach c as closely as you like, but you can never reach it, because the energy required to accelerate increases to infinity.

You've got the idea, and we understand you now, but no-one else would, because you keep saying "speed" when you mean "acceleration".

 

[ynot]

Still not quite right:
Speed does not stop at c. The speed of light is a limit to the possible speed of an object so the speed never reaches c.
So in your terminology: Time dilation means that there is a limit to the amount that you can increase speed and that limit goes to zero as you approach the speed of light. Your last sentence should read
"This speed is the speed of light because speed increase goes to zero as the speed approaches c".

Remember that time dilation includes the speed of light and so the speed of light is a built-in limit. This is because a posulate of Special Relativity is

I meant that theoretically speed would stop at c if c could be reached, not that it could.

But only “speed increase goes to zero”, not the amount of speed that was developed to reach the point where this would happen, that remains as a constant speed slower than c that can't be increased.

 

[ynot]

Right!


Acceleration!!!!


The limit is the speed of light. You can approach c as closely as you like, but you can never reach it, because the energy required to accelerate increases to infinity.

You've got the idea, and we understand you now, but no-one else would, because you keep saying "speed" when you mean "acceleration".

By speed I mean constant speed. Acceleration is increasing speed. Any constant speed is dilated by some default amount.

 

[Mashuna]

But only “speed increase goes to zero”, not the amount of speed that was developed to reach the point where this would happen, that remains as a constant speed.

Confusing. If only there were some simple word you could use instead of "speed increase" that we could all understand. That would clear things up nicely.

 

[ynot]

Confusing. If only there were some simple word you could use instead of "speed increase" that we could all understand. That would clear things up nicely.

Not sure that it would. and I raise you a . . .

ETA - Acceleration is the simple word for "speed increase" (but you knew that didn't you . There doesn't seem to be a simple word for "constant speed".

 

[ynot]

Does anyone disagree with any of these statements? . . .

Dilation occurs regardless of whether a thing is moving at a constant speed or accelerating.

A constant speed is dilated a constant amount, and an accelerating speed is dilated an increasing amount.

The greater the amount of speed, that greater the amount of dilation.

Time dilation is essentialy the same as speed dilation.

 

[Reality Check]

Does anyone disagree with any of these statements? . . .

Dilation occurs regardless of whether a thing is moving at a constant speed or accelerating.

True.

A constant speed is dilated a constant amount, and an accelerating speed is dilated an increasing amount.

True

The greater the amount of speed, that greater the amount of dilation.

True.

Time dilation is essentialy the same as speed dilation.

False.
There is time dilation and there is speed dilation. They both happen but the scaling factor is different. They are not "essentialy the same".
The time dilation of the object is gamma times that of the observer.
The speed dilation of the object is gamma squared times that of the observer.
The only thing that is similiar is that as speed increases both the dilations of the object increase.