Question about time and measurement

[questionator89]

Hi PF people,
I am brand new to PF and this is my first post so please excuse and help correct any mistakes I make.
My question is about time, the perception of time and the units we measure it in.
I figured I would start this question with a statement because if my general understanding of this is wrong then this may be the problem to begin with.

So let's use two objects. One is traveling at high velocity and one slow. My understanding is that the object going slower will experience more units of time than the object going fast.

If this is true then my next question is do other planets (specifically in our solar system) experience the same passage of time?
If not does this mean if another Earth were duplicated and was traveling slower that these earth2 people would be many generations ahead of us?
If so does this mean that they are all traveling at the same speed due to the gravity of our sun?
Or that our solar system as a grouped unit is traveling at one speed?
Or that our Galaxy has an inherent velocity?

If our sun was also moving would time slow down as we went in the opposite direction our sun was traveling during our elliptical orbit?
And I would guess this would mean when we change velocity in any way we are leaving a time frame dimension or membrane or something?

Can someone actually just explain to me the whole time and speed thing?
is time a byproduct of speed? or is speed a byproduct of time? do they both just have to exist the way they do for anything to move or BE at all?

im sorry for the annoying way these questions were laid out, this is my first post and I didnt even complete high school.

 

[questionator89]

I just want to add.
If I were Dumbledore with a physics degree and created two clocks completely made of entangled particles so they were identical. I then make a spaceship and launch one of these clocks away at a very fast speed.
Would the clocks read the fast moving slow time, or the slow moving fast time?
Furthermore if i made a bar of copper+entangled duplicate, sent one with the clock, then put an electrical current through the one I kept with me, what would happen to the spaceship copper?
Does this create entangled electrons from a spooky distance?

 

[Nugatory]

So let's use two objects. One is traveling at high velocity and one slow. My understanding is that the object going slower will experience more units of time than the object going fast.

If this is true then...

It's not true.
There's another fairly recent thread on this: https://www.physicsforums.com/showthread.php?t=712960

 

[questionator89]

Lol, thank you Nugatory. This those answers seemed logical. We have to stop watching Brian Greene talk about stuff.

 

[harrylin]

Hi PF people,
I am brand new to PF and this is my first post so please excuse and help correct any mistakes I make.
My question is about time, the perception of time and the units we measure it in.
I figured I would start this question with a statement because if my general understanding of this is wrong then this may be the problem to begin with.

So let's use two objects. One is traveling at high velocity and one slow. My understanding is that the object going slower will experience more units of time than the object going fast.

Hi welcome to physicsforums.

That is quite correct if you measure as follows:

A------------------------------B

Let's say that you have two identical atomic clocks with identical readings at point A. Now clock 1 is moved fast from A to B, and clock 2 is moved slowly from A to B. Then you compare the two clocks at B and you will find that clock 1 is behind on clock 2. In other words, the clock that moved slower will have recorded more units of time than the clock that moved fast.

Most other questions are perhaps covered in the other thread.

[..] is time a byproduct of speed? or is speed a byproduct of time? do they both just have to exist the way they do for anything to move or BE at all? [..]

Time and speed are human made concepts; most probably the universe doesn't depend on our existence. If nothing moved at all then there would be no speed to be measured. And as time measurements are based on motion, there also would be no time.

I just want to add.
If I were Dumbledore with a physics degree and created two clocks completely made of entangled particles [..]

I don't know if that is possible. And as your question involves SR+QM, that is a question to ask in the general physics forum.

 

[questionator89]

Thanks Harrylin I will move this question to general physics.
The way you explained that brings up my previous questions again it seems.
Although the objects I was describing weren't traveling from one point to another. The way you explained it is obvious, the slower object didn't reach the point B spot till much later and would obviously count more units of time.
Really what i thought was happening was if an outside observer were to look at both the clocks (and he had a clock) and after a certain amount of time by his clock, he would check the clocks of the 2 moving objects and see if there was a discrepancy.
I was listening to Ray Kurzweil spiel off about obvious stuff (no disrespect, he's brilliant, but his singularity theory is just an inevitable outcome of any form of education) and he said " an astronaut that orbits the Earth at a fast rate will actually experience less time than the people on earth, not just his perception but actual clocks".

This actually seems to be a very commons misconception. The closer you come to the speed of light the less time you experience in comparison to a slow object.

Anyways, you say time and speed are human made concepts. Not really man, i would say they are the words we use to describe something that's actually happening.

even a non sentient object will experience time. Thorium breaks down for example. I am sure they can "experience" speed as well.

 

[Drakkith]

I was listening to Ray Kurzweil spiel off about obvious stuff (no disrespect, he's brilliant, but his singularity theory is just an inevitable outcome of any form of education) and he said " an astronaut that orbits the Earth at a fast rate will actually experience less time than the people on earth, not just his perception but actual clocks".

This actually seems to be a very commons misconception. The closer you come to the speed of light the less time you experience in comparison to a slow object.

From here: http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html

Because an observer on the ground sees the satellites in motion relative to them, Special Relativity predicts that we should see their clocks ticking more slowly (see the Special Relativity lecture). Special Relativity predicts that the on-board atomic clocks on the satellites should fall behind clocks on the ground by about 7 microseconds per day because of the slower ticking rate due to the time dilation effect of their relative motion.

Further, the satellites are in orbits high above the Earth, where the curvature of spacetime due to the Earth's mass is less than it is at the Earth's surface. A prediction of General Relativity is that clocks closer to a massive object will seem to tick more slowly than those located further away (see the Black Holes lecture). As such, when viewed from the surface of the Earth, the clocks on the satellites appear to be ticking faster than identical clocks on the ground. A calculation using General Relativity predicts that the clocks in each GPS satellite should get ahead of ground-based clocks by 45 microseconds per day.

The combination of these two relativitic effects means that the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)!

 

[harrylin]

[..] Although the objects I was describing weren't traveling from one point to another. The way you explained it is obvious, the slower object didn't reach the point B spot till much later and would obviously count more units of time. [..]

That's not what I wrote. Instead, I wrote that the two clocks that started out synchronously are out of sync after the travel. Indeed, according to the "rest frame" measurements, the faster moving clock ticked slower during the journey than the slower moving clock. I thought that perhaps that was what you had in mind.

Really what i thought was happening was if an outside observer were to look at both the clocks (and he had a clock) and after a certain amount of time by his clock, he would check the clocks of the 2 moving objects and see if there was a discrepancy.

Yes, that is also correct, if the outside observer uses an inertial reference system for measurements and he/she "sees" by means of making a standard assumption about the time delay for the signals of those distant clocks to reach his/her clock. But since you had not mentioned a third clock, I interpreted what you said such that it was possible to compare the two clocks side by side. That's much simpler and more direct, as you don't need to make assumptions about signal transfer.

I was listening to Ray Kurzweil spiel off about obvious stuff (no disrespect, he's brilliant, but his singularity theory is just an inevitable outcome of any form of education) and he said " an astronaut that orbits the Earth at a fast rate will actually experience less time than the people on earth, not just his perception but actual clocks".

This actually seems to be a very commons misconception. The closer you come to the speed of light the less time you experience in comparison to a slow object.

See Drakkith's reply. If you try to understand special relativity, astronauts in orbit can be confusing as there you have to do with general relativity: the higher you are the faster your clocks tick. That makes it more complex, and not good for learning SR.

Anyways, you say time and speed are human made concepts. Not really man, i would say they are the words we use to describe something that's actually happening.[..]

Yes of course, those concepts are based on observations; and for sure, without observing motion we cannot create the concept of time. And our understanding and description of what is actually happening has changed with relativity theory.

 

[Dale]

I just want to add.
If I were Dumbledore with a physics degree and created two clocks completely made of entangled particles so they were identical. I then make a spaceship and launch one of these clocks away at a very fast speed.
Would the clocks read the fast moving slow time, or the slow moving fast time?

They would each read their own proper time. Entanglement doesn't change anything locally observable on either particle or ensemble.

 

[questionator89]

Thanks again Harrylin,
So I am not good at interpreting what is being said to me I think.
So what you and Drakkith are saying is that a sort of gravity-friction slows down the mechanism the clock runs by?
Atom oscillations or however these clocks run, move faster away from the space-time warp caused by our massive earth?
Because if they move faster away from Earth that is the opposite of what I thought.
I thought the faster you were going the slower time would tick.

Lets say we had two musicians with perfect timing, one on Earth and one in a fast orbiting spaceship. Would they experience a difference in time?
I am just trying to think of a non mechanical clock or some way to ask this question better.

DaleSpam, maybe I don't understand entanglement. If the two clocks were entangled does this not mean whatever one clock does the other has to do?
If one was in a denser gravity field it would be subject to different environmental variables. Like, would this break entanglement or would one clock decide what time both clocks display?

I really appreciate u three taking the time to read and post.
Should I move this question to GR? or once its posted its kind of too late or what?

 

[Drakkith]

Thanks again Harrylin,
So I am not good at interpreting what is being said to me I think.
So what you and Drakkith are saying is that a sort of gravity-friction slows down the mechanism the clock runs by?

No, it's just stand time dilation due to relative motion and gravity.

Atom oscillations or however these clocks run, move faster away from the space-time warp caused by our massive earth?
Because if they move faster away from Earth that is the opposite of what I thought.
I thought the faster you were going the slower time would tick.

The orbiting satellites are ticking slower because they are moving relative to us, AND they are they are ticking faster because they are further away from Earth and experience less gravity.

Lets say we had two musicians with perfect timing, one on Earth and one in a fast orbiting spaceship. Would they experience a difference in time?
I am just trying to think of a non mechanical clock or some way to ask this question better.

Yes, they would experience a difference in the passage of time.

DaleSpam, maybe I don't understand entanglement. If the two clocks were entangled does this not mean whatever one clock does the other has to do?

No, not at all. That's not how entanglement works, but I'm afraid explaining it is not my specialty. Hit up the Quantum Physics forums and you should be able to find plenty of info on it.

 

[harrylin]

Thanks again Harrylin,
So I am not good at interpreting what is being said to me I think.
So what you and Drakkith are saying is that a sort of gravity-friction slows down the mechanism the clock runs by? Atom oscillations or however these clocks run, move faster away from the space-time warp caused by our massive earth? [..]

Quite the contrary.
While Drakkith thinks that you can already handle the complexity of two different time dilation effects, I suggested to stick to special relativity's time dilation - ignore the effects of gravitation on "time". You can do that if your objects stay roughly at the same altitude. Then you have for example the measurement situation that I described. No gravity effects and thus also no space-time warps, and no friction effects. Just plain time dilation from speed. If you try to learn one thing at a time, there is a chance that you may actually progress. Except of course if you are a genius, then you can perhaps handle everything at once.

I thought the faster you were going the slower time would tick. [..]

That is an imprecise formulation of what I told you twice with a precise description of measurements ...

Also what you ask next is too imprecise to know what you are asking. As a matter of fact, such imprecise descriptions result in misunderstandings such that two people can give contrary answers because they understand what you say inversely - compare posts and !

 

[harrylin]

Thanks again Harrylin,
So I am not good at interpreting what is being said to me I think.
So what you and Drakkith are saying is that a sort of gravity-friction slows down the mechanism the clock runs by? Atom oscillations or however these clocks run, move faster away from the space-time warp caused by our massive earth? [..]

Quite the contrary.
While Drakkith thinks that you can already handle the complexity of two different time dilation effects, I suggested to stick to special relativity's time dilation - ignore the effects of gravitation on "time". You can do that if your objects stay roughly at the same altitude. Then you have for example the measurement situation that I described. No gravity effects and thus also no space-time warps, and no friction effects. Just plain time dilation from speed. If you try to learn one thing at a time, there is a chance that you may actually progress. Except of course if you are a genius, then you can perhaps handle everything at once.

I thought the faster you were going the slower time would tick. [..]

That is an imprecise formulation of what I told you twice with a precise description of measurements ...

Also what you ask next is too imprecise to know what you are asking. As a matter of fact, such imprecise descriptions result in misunderstandings such that two people can give contrary answers because they understand what you say inversely - compare posts 3 and 5!

 

[questionator89]

hahaha i was comparing these posts and did find it confusing . What I understand now is that I don't understand this and need to read up a bit lol.
I am definitely not a genius.

So special relativity and time dilation. I will re-read what you have said, too.
Thanks man
Since you are answering so diligently though, could you explain why my questions about measuring time on other planets, and the whole Earth 2 getting more work done than earth1 people question?
It almost sounds like what I asked is possible...

 

[questionator89]

so upon further reading I am more confused. but I think it is a good thing.

So do we consider the Earth " at rest" ?
Based on what I have read is it accurate to say that if we could bring a golf ball to absolute zero (i know this isn't possible, I have seen the helium videos, very cool) that everything would age infinitely to the golf ball? assuming we don't unfreeze it.
Or inversely that if we could reach the speed of light time would stop?

I am going to be honest, the real reason I am asking is because I have a question about Drakes equation ( how many forms of intelligent life are in the universe) and a little part at the end of the explanation where you can multiply this by how many times a single planet could produce intelligent life.
I guess the theory is if a planet can produce one intelligent life form then why not another, or 100?
Anyways, I am wondering how accurate this little thing could be (i know not very accurate considering what it is trying to figure out) if they do not take the velocity of these objects (planets) into account over all the years.

 

[Dale]

DaleSpam, maybe I don't understand entanglement. If the two clocks were entangled does this not mean whatever one clock does the other has to do?

No. Entanglement is a quantum mechanical phenomenon. If you have some property which is quantum-mechanically uncertain, e.g. the polarization of some photon, and if you produce entangled particles, then if you measure the property you will find that the measured property on one is perfectly correlated with the measured property on the entangled partner.

However, each ensemble, on its own, is simply random. It is only when you get the information from the other ensemble that you can obtain the correlations. This is what prevents any instantaneous information transfer through entanglement.

 

[Drakkith]

so upon further reading I am more confused. but I think it is a good thing.

So do we consider the Earth " at rest" ?

For everyday little things we can consider the Earth to be at rest, but there is no "absolute" rest frame.

Based on what I have read is it accurate to say that if we could bring a golf ball to absolute zero (i know this isn't possible, I have seen the helium videos, very cool) that everything would age infinitely to the golf ball? assuming we don't unfreeze it.
Or inversely that if we could reach the speed of light time would stop?

What? Absolute zero has nothing to do with this, that is temperature.

I am going to be honest, the real reason I am asking is because I have a question about Drakes equation ( how many forms of intelligent life are in the universe) and a little part at the end of the explanation where you can multiply this by how many times a single planet could produce intelligent life.
I guess the theory is if a planet can produce one intelligent life form then why not another, or 100?
Anyways, I am wondering how accurate this little thing could be (i know not very accurate considering what it is trying to figure out) if they do not take the velocity of these objects (planets) into account over all the years.

Since we have only a single planet with a single intelligent species it is impossible to come up with any conclusions that aren't simply guesses.

 

[WannabeNewton]

The Earth is obviously at rest in its own rest frame by definition. The question is not whether one can consider it to be "at rest" because every massive object has a rest frame. The question is whether one can consider it an inertial frame, which one can approximately.

 

[questionator89]

Right, so when I said absolute zero i mean not moving, not even the atoms and electrons, no velocity.
sorry it wasn't the right word at all.
In many fields of physics you smart guys are spending a huge amount of time trying to make conclusions based on guesses though.
And based on the two theories that I am aware of life can start from extremophile bacteria on a meteor, or possibly in the presence of amino acids and a specific frequency or something.
In any case we are just guessing about planets at a certain distance from the start they orbit which potentially have water. These are the planets we would guess have an environment and atmosphere capable of sustaining life.
In any case my question isn't about the validity of the drake equation, that's why I didn't bring it up in the initial post.
WannabeNewton that is very interesting, it was something I was going to ask. Can we figure out how fast we are moving based on our time experience or something?
My big questions are, do other planets in our solar system experience time differently?
And my ultimate sci-fi curiosity is; if there was a planet in the goldy-locks zone or w.e its called which was inhabited by intelligent life and orbiting its star at a very slow velocity, would these guys be way ahead?
how far can we take this time dilation thing?

 

[Drakkith]

Right, so when I said absolute zero i mean not moving, not even the atoms and electrons, no velocity.
sorry it wasn't the right word at all.

The motion of the particles that make up an object do not affect whether that object experiences time dilation. It is only the relative motion of the object as a whole.

WannabeNewton that is very interesting, it was something I was going to ask. Can we figure out how fast we are moving based on our time experience or something?

We could if we had an absolute frame of reference that everything could be compared against. But there is not.

My big questions are, do other planets in our solar system experience time differently?

Sure. Both SR and GR effects will determine how quickly time passes anywhere, even on other planets. But this is no different than here on Earth. If I climb to the top of one of the nearby mountains I will be experiencing time at a faster rate than someone down at the base. These effects are always present, they are simply too small to detect without very precise clocks.

And my ultimate sci-fi curiosity is; if there was a planet in the goldy-locks zone or w.e its called which was inhabited by intelligent life and orbiting its star at a very fast velocity, would these guys be way ahead?
how far can we take this time dilation thing?

Even the fastest orbiting planets are still moving at a VERY VERY small percentage of the speed of light. As such, the differences in elapsed time per day would be measured in nanoseconds or microseconds even when comparing ourselves to the fastest planets.

 

[questionator89]

Awesome. Thank you Drakkith. That was the answer i was looking for.
But in the grand scheme those microseconds would add up to a huge difference in potential. I would guess.
Especially if say... we started from single celled organisms and "they" started as single cell organisms at the same time. But they stay in this state for 200 million years and we stay there for 300. or whatever a plausible number is.

And why do we need an absolute frame of reference? if we were measuring the difference between two planets say, couldn't we use any frame of reference as comparison? Even the Earth? just one specific clock?.
Couldnt we then say, this clock is moving at this rate and records this much time, this clock is moving at another rate and records this much time, then math'er on back to zero?

This must be annoying for u guys so I really appreciate the respones haha.
I try to explain things in my field of work to people who know nothing about it and it probably goes the way this thread is going most of the time.

 

[questionator89]

I should clarify;
I sort of merged two of my questions in that last post.
So measuring the difference between two planets.
Then measuring what rate of time we give to our planet (or solar system,galaxy, however it is grouped together)
compared to what a "0% the speed of light" bit of matter would experience in time.

 

[Drakkith]

Awesome. Thank you Drakkith. That was the answer i was looking for.
But in the grand scheme those microseconds would add up to a huge difference in potential. I would guess.
Especially if say... we started from single celled organisms and "they" started as single cell organisms at the same time. But they stay in this state for 200 million years and we stay there for 300. or whatever a plausible number is.

If my math is right, assuming we were 50 microseconds faster per day than they were, that's a difference of 1 part in 1.7 billion. IE it would take 1.7 billion days, or 4.6 million years, to develop 1 days worth of time difference.

And why do we need an absolute frame of reference? if we were measuring the difference between two planets say, couldn't we use any frame of reference as comparison? Even the Earth? just one specific clock?.
Couldnt we then say, this clock is moving at this rate and records this much time, this clock is moving at another rate and records this much time, then math'er on back to zero?

There is no zero, there are only comparisons.

I should clarify;
I sort of merged two of my questions in that last post.
So measuring the difference between two planets.
Then measuring what rate of time we give to our planet (or solar system,galaxy, however it is grouped together)
compared to what a "0% the speed of light" bit of matter would experience in time.

The passage of time in all inertial frames of reference, as measured from an observer in that frame, is always 1 second per second. You NEVER observe time dilation in your own frame. So you cannot measure your own time dilation without another frame to compare your clock against.

 

[questionator89]

If my math is right, assuming we were 50 microseconds faster per day than they were, that's a difference of 1 part in 1.7 billion. IE it would take 1.7 billion days, or 4.6 million years, to develop 1 days worth of time difference."

Well, that is pretty inconsequential.

There is no zero, there are only comparisons"

Well maybe there is no zero. But there has to be an upper limit of time rate for a super slow moving object. Can we make an object have so little inertia that it ages much faster?
What is getting to me is, what if the only reason that time doesn't pass extremely fast before us and we all just age, and everything around us ages until the sun dies out, is specifically BECAUSE we happen to be (and everything in view) speeding in a particular direction. as a universe.
But then I guess if this were true we could go in the opposite direction and time will go fast and then slow again.
In all these scenarios I am assuming we all have super fast spaceships.

that frame, is always 1 second per second. You NEVER observe time dilation in your own frame. So you cannot measure your own time dilation without another frame to compare your clock against.

Right, I can see how that would be. In every scenario I suggested there was a clock per area though. I am assuming there would be a way to check the difference between both these clocks too.
If we were to send a clock out of the atmosphere to stay in one place and have us pick it up on the way back around, what would the time difference be from what we experienced on earth?
if its a small number, does this mean that even as the clock sat there waiting for us to pick it up that it had a fast intertia that we can't perceive because we are all speeding in a direction?
It seems that by the assumption that if you reach the speed of light time will stop, then if you reach a zero inertia point the universe would age infinitely in front of you.

and does this mean to a photon time is nothing? like if the photon was sentient, it would be born then rather than experiencing the 8 mins we know the light takes to reach the Earth it is just instantly on the first thing it touches?
And i guess if it bounced it would seemingly be on all the objects it touched all at once.

 

[Drakkith]

Well maybe there is no zero. But there has to be an upper limit of time rate for a super slow moving object. Can we make an object have so little inertia that it ages much faster?

You're missing the point. It's all about reference frames. There will ALWAYS be some object traveling through space that could view you as traveling at 99%+ c. According to that object YOU are experiencing massive time dilation. And that object would be perfectly correct in saying that. There is no frame that has a special status as "the" frame to measure against to determine things like "least time dilation".

What is getting to me is, what if the only reason that time doesn't pass extremely fast before us and we all just age, and everything around us ages until the sun dies out, is specifically BECAUSE we happen to be (and everything in view) speeding in a particular direction. as a universe.
But then I guess if this were true we could go in the opposite direction and time will go fast and then slow again.
In all these scenarios I am assuming we all have super fast spaceships.

Everything within sight is either stationary or traveling at a VERY small fraction of c relative to your frame. That's why you don't notice any relativistic effects on a day to day basis.

If we were to send a clock out of the atmosphere to stay in one place and have us pick it up on the way back around, what would the time difference be from what we experienced on earth?
if its a small number, does this mean that even as the clock sat there waiting for us to pick it up that it had a fast intertia that we can't perceive because we are all speeding in a direction?

This is getting a little complicated. It's pretty much another version of the Twin Paradox. The Earth would be the twin that accelerates one way and then comes back. (At least I think so)

It seems that by the assumption that if you reach the speed of light time will stop, then if you reach a zero inertia point the universe would age infinitely in front of you.

We cannot reach the speed of light and we cannot assume that time would stop anyways. Our math simply doesn't work if you insert c as your velocity.

Also, consider the following. Let's say you go into space. You accelerate back and forth in EVERY direction in an attempt to find out in which direction you need to go in order to reach "zero inertia". So you go one way, and then another, and then another. Over and over again, in every possible direction. But you cannot find a direction in which to accelerate to cancel out your inertia. This is because you already have zero inertia in your own frame of reference and there is no "absolute" frame that determines the time dilation for everyone. It's all RELATIVE between objects based on their velocities with respect to each other.

and does this mean to a photon time is nothing? like if the photon was sentient, it would be born then rather than experiencing the 8 mins we know the light takes to reach the Earth it is just instantly on the first thing it touches?
And i guess if it bounced it would seemingly be on all the objects it touched all at once.

We cannot have a frame of reference in which we are traveling at the speed of light, so we cannot make conclusions about what an observer would experience at that speed.

 

[questionator89]

I can comprehend what is being said to me.
I think what is happening is I am not asking the question in the proper way.
And the question has changed as you have taught me more about how time dilation works.

So, an easy reference would be "earth time" which is 1 second per Earth second in my question.
But if we were to be going 65% c (is this how we represent the speed of light?) we would be experiencing time as for every 5 Earth seconds we feel 1 second. ( i don't know the math)
It seems that as you reach close to the speed of light ( this is my interpretation) that the discrepancy between what we perceive as time traveling fast, and what our original resting frame of perceived time, is a big difference.

But it doesn't work like this in the opposite direction? I intuitively feel this doesn't follow a normal pattern of physics (but i know nothing)

It would seem that, if we were to place a clock somewhere in space, which to us is seemingly not moving at all
that the difference would be something like 1.0000000123 seconds per Earth second get recorded.
This seems like a very small discrepancy.
It should be that we can decrease our velocity and inversely experience 5 seconds our time for every 1 Earth second, and see everything slowly meander about.

Like Drakkith said, we could be perceived from another object to be experiencing extreme time dilation. Its all about perception and reference points.

But obviously if we can't make something "rest" enough where it ages a considerable amount,while we experience 1 second per second does this imply a resting velocity? or inertia maybe is the right word?
This dimension has inertia built into it for a resting object to experience such a small discrepancy between units of time between a resting speed and a fast orbiting speed.

In many scenarios it is suggested that you could rip about in a spaceship for 5 years at an incredibly fast rate and return to Earth to see that they have aged 20 years. Is this wrong? not the math I have said because I honestly have no idea, but the concept in general?

It almost sounds like it is easier to slow time down by traveling incredibly fast, than to speed time up by traveling incredibly slow.

I don't know how much science fiction I read has any credibility to it at all, but could high density electromagnetism shield an object from inertia and cause it to age to infinity?
maybe forget this last question...

 

[questionator89]

Im going to move this to a new thread to try an get more responses.
So Drakkith and Harrylin if you are still interested in guiding me in this question please refer to the link that says
"Inertia and resting time rate"

 

[adrian_m]

The motion of the particles that make up an object do not affect whether that object experiences time dilation. It is only the relative motion of the object as a whole.

Hang on! That's not true. If an object as a whole experiences time dilation, then the motion of each particle that makes up the object must undergo the same time dilation. Otherwise it would violate the postulate 'the laws of physics are the same for all observers'.

 

[Drakkith]

Hang on! That's not true. If an object as a whole experiences time dilation, then the motion of each particle that makes up the object must undergo the same time dilation. Otherwise it would violate the postulate 'the laws of physics are the same for all observers'.

Of course. I wasn't saying anything to contradict that.

 

[WannabeNewton]

Hang on! That's not true. If an object as a whole experiences time dilation, then the motion of each particle that makes up the object must undergo the same time dilation. Otherwise it would violate the postulate 'the laws of physics are the same for all observers'.

This is incorrect. The constituent fluid elements making up a macroscopic object need not have the same individual motions, by any means, as the macroscopic object, viewed relative to some inertial frame. Your last sentence has no relevance whatsoever to the rest of your claim.

 

[adrian_m]

This is incorrect. The constituent fluid elements making up a macroscopic object need not have the same individual motions, by any means, as the macroscopic object, viewed relative to some inertial frame. Your last sentence has no relevance whatsoever to the rest of your claim.

Take a concrete example. You and I are both traveling inertially at different velocities.

I see your clock's 'second hand' tick over a second, moving at a certain angular velocity. The elapsed time by my clock is different than 1 second, so you have a time dilation with respect to me.

Is it possible that I will not necessarily see the 'atoms' in your second hand move at the same angular velocity, or preserve their positions with respect to each other at any time? That would only be possible if the physical laws in your frame were different than mine.

Unless proportions within a macroscopic object are preserved, it does not make much sense to say that a macroscopic object has 'a' time dilation.

 

[WannabeNewton]

Unless proportions within a macroscopic object are preserved, it does not make much sense to say that a macroscopic object has 'a' time dilation.

This is exactly why your claim above is incorrect. If we represent an extended body by a congruence of time-like curves and have an external observer who intersects a curve in the congruence at a given event on the curve then the external observer can boost to the instantaneous inertial frame of the fluid element described by said curve and the time dilation factors will be attributed on this individual level. Your claim was "If an object as a whole experiences time dilation, then the motion of each particle that makes up the object must undergo the same time dilation.". If you are talking about extended bodies and bringing into the picture the constituent fluid elements then your first clause by itself makes no sense.

A simple example is given by representing a rigidly rotating disk of angular velocity ##\omega## by a congruence of time-like curves. In order to boost from a background global inertial frame to the instantaneous rest frame of each fluid element in the congruence simultaneously, one uses the gamma factor ##\gamma = \frac{1}{\sqrt{1 - \omega^2 r^2}}## which clearly is different for fluid elements situated at different ##r## on the disk.

 

[phyti]

In the 'ideal' rest frame, there is no relative motion of the components, thus the fictional 'center of mass' moves at a constant speed. In the 'real world' rest frame the component motion varies on a molecular/atomic level (even if only due to thermal energy) for extremely short durations. There would be a mean rate of time dilation with small fluctuations. These would be insignificant at small fractions of c. I won't speculate on the significance at high fractions of c.

 

[WannabeNewton]

There is no rest frame for an entire time-like congruence. One can go to the rest frame of a given fluid element in the congruence and in this frame i.e. relative to this fluid element, neighboring fluid elements can have both angular and radial velocity.

 

[phyti]

...
It would seem that, if we were to place a clock somewhere in space, which to us is seemingly not moving at all
that the difference would be something like 1.0000000123 seconds per Earth second get recorded.
This seems like a very small discrepancy.
It should be that we can decrease our velocity and inversely experience 5 seconds our time for every 1 Earth second, and see everything slowly meander about.
...

Two observers A and B with different speeds, do not see time dilation for the other. Clocks are frequencies, therefore they observe doppler (frequency) shifts, positive if approaching, negative if receding. It's similar to the changing pitch of a sound passing by. The aging (accumulation of time) for each clock can only be done by a comparison of the two at a common location, as was shown in post 5 by harrylin.

If you pass by another clock, decreasing your speed each time, the maximum length tick will occur when you stop next to it. You can't go any slower, i.e., moving clocks will run slower, but never faster. In your above example, the difference would be zero, the clock reads 1.00.