WHY? is the relationship between speed and time exponential?

In summary, the relationship between speed and time is exponential because as objects approach the speed of light, their time dilation and length contraction effects become more apparent, resulting in a much greater difference between the proper time interval and the observer's time. This is due to the Lorentz factor in the time dilation formula and is a fundamental law of time. The reason for this relationship being exponential is not answerable, it is simply the way the math works out.
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DeepThoughts
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WHY!? is the relationship between speed and time exponential?

I am actually a finance major but I like to learn about physics on my spare time. One of the more fundamental concepts I am having a hard time understanding is why the relationship between speed and time is exponential. Can someone explain this is simple terms please?
 
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Not really what do you mean, why is time and speed exponential as a mass object approaches c, is that what you mean, even then it is not clear at all?

You may need to ask a more well defined question?
 
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DeepThoughts said:
I am actually a finance major but I like to learn about physics on my spare time. One of the more fundamental concepts I am having a hard time understanding is why the relationship between speed and time is exponential. Can someone explain this is simple terms please?

We are curious as well, because obviously, none of us know what you are talking about.

I can point out one relationship, v = s/t, where is the displacement. Where is the "exponential" here?

Zz.
 
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Please excuse my vagueness. What I am asking is, for example in a particle accelerator, when particles are sped up close to the speed of light their time relative to us becomes slower. What I am asking is why the time dilation is greater in only the much higher percentages of the speed of light like 99.999% of C. From 1% to 99% there is not much of this effect. Why is this relationship exponential.
 
  • #5


DeepThoughts said:
Please excuse my vagueness. What I am asking is, for example in a particle accelerator, when particles are sped up close to the speed of light their time relative to us becomes slower. What I am asking is why the time dilation is greater in only the much higher percentages of the speed of light like 99.999% of C. From 1% to 99% there is not much of this effect. Why is this relationship exponential.

Can you please write down this exact relationship that you are referring to? That will be a very good and CLEAR starting point.

Zz.
 
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DeepThoughts said:
Please excuse my vagueness. What I am asking is, for example in a particle accelerator, when particles are sped up close to the speed of light their time relative to us becomes slower. What I am asking is why the time dilation is greater in only the much higher percentages of the speed of light like 99.999% of C. From 1% to 99% there is not much of this effect. Why is this relationship exponential.
Am I getting you wrong or are you asking why c is the speed limit of non mass objects such as the photon and why approaching c is the speed limit of mass objects?

What you are in fact asking is why the equations make c the constant it is or the limit of speed in time. This is a consequence of relativity and the laws of time, they are taken to be true because nothing contradicts them, they are derived as a consequence there of, not as something that comes from a principle that can be derived further than the equations and the resultant experiments we have at least tried themselves.

That is then not a question that is answerable, it just seems that as mass objects approach c, they experience a time dilation/length contraction that makes the concerns of speed relative to another co moving body always less than c in mass systems. It's a fundamental law of time, we don't know why the limit is c, we only know that asymptotically no mass object will ever reach it because the time and space issues forbid it.

It's not an exponential though, although I took you to mean you thought it was. Energy concerns blow up at speeds approaching c, but they are not e^x or an exponential concern in those equations.

EDIT:

Oh and what Zapper z said, let's start with a clear question, before we proceed to a clear answer. :smile:
 
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Do you know the lorentz factor and the time dilation formula? From the time dilation formula it is clear that the v^2/c^2 term is negligible for smalll speeds, as it will roughly equal zero. We then see that as the velocity approaches the speed of light, these changes become more apparent, and there is a much greater difference between the proper time interval and the observer's time. Hope i could answer you question. Maybe you can take a look at this graph also: http://www.thebigview.com/spacetime/timedilation.html
 
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Actually Cerlid and Gravitational have provided the answer I am looking for. In Gravitationals link and referral to the Lorentz factor in the time dilation formula, there is the exact equation and graph I am trying to refer to. My question specifically I suppose is why is the relationship not linear. And the answer I am gathering is "Because that's the way the math works out." and as Cerlid points out the reason for this is not answerable. Thanks for the patience with my intelectual shortcomings!
 
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Every object has a path or trajectory through spacetime, and there are certain paths that do not change no matter how you move relative to the object on such a path--a path that light can take. Why the world works this way is big, big question, but if you can accept it on its face, then the formulas for how objects accelerate and behave follow.
 
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DeepThoughts said:
Please excuse my vagueness. What I am asking is, for example in a particle accelerator, when particles are sped up close to the speed of light their time relative to us becomes slower. What I am asking is why the time dilation is greater in only the much higher percentages of the speed of light like 99.999% of C. From 1% to 99% there is not much of this effect. Why is this relationship exponential.

An "exponential" growth pattern is one in which something doubles in a fixed amount of time. And then doubles again in the same amount of time. And so on. This would include things like the growth of bacteria in a medium, the growth of money in your savings account or the splitting of atoms in an atomic bomb.

The term "exponential" is also used to describe decay patterns where something shrinks to half in a fixed amount of time and then half of that in the same amount of time. This would include things like radioactive decay or the concentration of a substance after multiple dilutions.

It is popular to use the term "exponential" to refer to things that grow "very fast". That usage is incorrect. (It tends to indicate either sloppy thinking or a desire to persuade without regard for the facts).

Some things grow without bound as some limiting value is approached. This would include things like the pressure in a tank as the volume shrinks to zero. That kind of growth is called "asymptotic".

Time dilation is grows "asymptotically" as relative velocity approaches c.
 
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DeepThoughts said:
Actually Cerlid and Gravitational have provided the answer I am looking for. In Gravitationals link and referral to the Lorentz factor in the time dilation formula, there is the exact equation and graph I am trying to refer to. My question specifically I suppose is why is the relationship not linear. And the answer I am gathering is "Because that's the way the math works out." and as Cerlid points out the reason for this is not answerable. Thanks for the patience with my intelectual shortcomings!

You should also learn something from this, that you need to be careful with how you describe things. Everything in physics has an underlying mathematical formulation. You simply cannot use terms such as "exponential" without understanding what it means! This is, after all, a physics forum, and when you use something like that, most of us know what it is. But you obviously didn't, but you are using it based on some mistaken idea. It creates a horrible confusion, not to mention, a lot of vague misunderstanding.

Zz.
 
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DeepThoughts said:
My question specifically I suppose is why is the relationship not linear. And the answer I am gathering is "Because that's the way the math works out." and as Cerlid points out the reason for this is not answerable.
I actually think it is answerable. The math is founded on two postulates, first, the laws of physics are the same in all inertial reference frames, second, the speed of light is the same in all inertial reference frames. With mathematically precise expressions of those two postulates it is possible to derive the Lorentz transform, including the non linear relationship you noticed.
 
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The relation cannot be linear because you can't reach infinity by increasing at a linear rate over a finite distance. Simply, if you divide infinity into equal steps from speed 0 to c, then that means the dilation is infinity/2 at c/2 speed? That makes no sense, so the increase must be more than linear, and more than exponential even (which never reaches infinity over a finite domain). The actual relationship is something like
[itex]\gamma=\frac{1}{\sqrt{1-\beta^2}}[/itex]
which goes to infinity as beta goes to 1.
 
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DeepThoughts said:
Actually Cerlid and Gravitational have provided the answer I am looking for. In Gravitationals link and referral to the Lorentz factor in the time dilation formula, there is the exact equation and graph I am trying to refer to. My question specifically I suppose is why is the relationship not linear. And the answer I am gathering is "Because that's the way the math works out." and as Cerlid points out the reason for this is not answerable. Thanks for the patience with my intelectual shortcomings!

If I may though the maths is far more important than the explanations I gave (gravitational hinted at a better explanation), you'll find out why things are what they are, and more importantly still is how the model applies to experiment. I just didn't know what level you are at so I didn't want to bombard you with equations.

If you really want to understand why c is the speed limit of the universe, then you are on the right track but the equations and the science will spell it out far better in terms of an overall understanding. You have some maths knowledge, if you're really interested, and have the time, there are worse things to do with maths. Economics for example, gah that's all unpredictable, physics is kinda tight, at least in special relativity. :smile:

Which leads to:

DaleSpam said:
I actually think it is answerable. The math is founded on two postulates, first, the laws of physics are the same in all inertial reference frames, second, the speed of light is the same in all inertial reference frames. With mathematically precise expressions of those two postulates it is possible to derive the Lorentz transform, including the non linear relationship you noticed.

Precisely get the model right and everything is a consequence of it. The beauty of it is everything is a consequence of taking something as being constant, it works because of that relationship as well in non inertial frames as it does in inertial ones, with c being that thing where everything else falls nicely into place from.
 
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DeepThoughts said:
I am actually a finance major but I like to learn about physics on my spare time. One of the more fundamental concepts I am having a hard time understanding is why the relationship between speed and time is exponential. Can someone explain this is simple terms please?

x = vt
v = x/t
If we keep x fixed and increase t, graph of velocity falls like an exponentially decreasing function.

See the JPG graph. Is this something you are referring to?
[sorry, can't insert a jpg picture]
 

FAQ: WHY? is the relationship between speed and time exponential?

What is the relationship between speed and time?

The relationship between speed and time is that as speed increases, the time it takes to travel a certain distance decreases. This is because speed is defined as the distance traveled per unit of time. Therefore, the higher the speed, the shorter the amount of time it takes to travel a certain distance.

Why is the relationship between speed and time exponential?

The relationship between speed and time is exponential because as speed increases, the time it takes to travel a certain distance decreases at an increasing rate. This is due to the fact that as speed increases, the distance traveled per unit of time also increases, resulting in a steeper slope on a graph of speed versus time.

How does the relationship between speed and time affect motion?

The relationship between speed and time directly affects motion. As speed increases, the distance traveled per unit of time increases, resulting in a faster and more efficient motion. On the other hand, as speed decreases, the distance traveled per unit of time also decreases, resulting in a slower and less efficient motion.

Is the relationship between speed and time consistent for all types of motion?

The relationship between speed and time is consistent for linear motion, where an object moves in a straight line at a constant speed. However, for other types of motion such as circular motion or accelerating motion, the relationship between speed and time may not be exponential, but rather follow different patterns.

How does the relationship between speed and time relate to the concept of velocity?

The relationship between speed and time is closely related to the concept of velocity, which is the speed of an object in a given direction. As speed increases, the velocity also increases, as the object is covering more distance in a shorter amount of time. Similarly, as speed decreases, the velocity also decreases.

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