Time dilation (part two)

[Damo2600]

Sorry everybody I've done it again:

 

Imagine two towers.

 

Now each tower has two each tower has a conveyor belt that moves a ball at a constant rate down the side of the tower and returns back up the side of the tower. The first tower is moving toward the second tower and the second tower is staionary. An observer on each tower calculates the time it takes for the their ball to travel down the tower and up again. The second observer calculates the elapsed time of the ball on the opposite tower. All four observers record equal times i.e. proving that the both the balls are moving at a constant speed. So the speed of light is a constant speed for all observers.

 

It appears there is two ways to view the results of this experiment.

 

1/ The first observer, in the first tower, and the second observer, in the second tower, view the same object to be moving at the same time, and speed over apparently different distances. So we could say that time is slowing down for the observer moving relevant to the ball.

 

However

 

2/ Would it not be equally satisfactory to state the ball is moving at a constant, over the same distance, all at the same time speed although the velocity by which you are moving away from the ball makes it appear that the ball is moving over a longer distance.

 

Now if time dilation actually occurs, and most people accept this as a fact, then the previous statement is untrue and it should not cause any offence. You should be able to understand the above reasoning and be able to rebuke it (No one is required to respond to this post in anyway). Now the second reasoning seems to be a reverse way of looking at relativity. That light for different observers (of different velocities) only appears to be moving over different distances. Makes sense in a mental sense does it not?

 

Damien

 

I mean come on the same light ray cannot be moving at two different distances. It is only moving in one direction.

[Damo2600]

I will use my femininity to get some more attention Buffy.

 

If I bounce my breasts on a train and somebody is off the train staring at them the time and speed of the bounces is the same for both observers. However the velocity of the train is playing with your head because it appears my breasts are moving further than they actually are.

 

In GR we state:

 

d * t = s

 

However if we add velocity to the situation we need to add it to both sides of the equation.

 

(d * t) + v = (s) +v

 

In SR we only add v to one side of the equation.

 

(d * t) + v = s

 

So if I place values on the movement of my breasts:

 

(distance my breasts travel)d = 20

(time my breast take to travel the distance)t = 10

(velocity of the train - how boring)v = 5 and

(speed of my breasts)s = 200

 

(d * t) + v = s

t = s/d - v

t = 200/20 - 5

 

So t now equals 5 and not 10.

 

If you add velocity to both sides of the equation t, s and d all remain constant.

 

I used my breasts to explain relativity to my boyfriend and finally he gets it.

So maybe this is a more conducive method of explaining myself.

 

Damien

[Damo2600]

O.k. guys I've thought about it and I know the answer.

 

If light travels perpendicularly from the roof of a moving train and is reflected back up from a mirror on the floor back up to the roof an observer will see the light travel at time t. The stationary observer will see the light travel in a v-shape and will record time t'. Both times are equal however the person on the train is experiencing time-dilation. Special Relativity.

 

What does this mean?

 

If the person stationary to the train flashes a light in a v-shape, equal to the one he sees on the train, and two stationary people record the two flashes (i.e. the stationary flash and the moving flash) they will both record equal times.

 

What does this mean?

 

The time dilation therefore is directly proportional to the velocity of the observer. So an event happening on a train will be observed in real time for the stationary observer. The observer on the train will experience every event stationary to the train to be happening twice the speed of the time dilation that has occured.

 

In my first example, at the start of this thread, the second observer in the first tower should not record a time that is equal to the other observers. His time is going much slower so he should see the ball moving faster than it is for the stationary first observer in the second tower. That is if special relativity is to hold correct.

 

That means that if I am moving on a train at a velocity, that makes my time speed half that of a stationary observer, the stationary observer should observe an event that is happening relative to me on the train in real time. However I would observe an event that is happening relative to an observer that is stationary to me in double time. Just like the *2 on your DVD player.

 

I cannot observe the events that are happening off the train to be 'time going slower' because my time is 'actually' going more slowly. If this were to be true there could not be any time dilation. In Special Relativity it states that if I am moving I experience myself to be stationary. If a stationary observer can observe actual time dilation then a moving observer cannot experience false time dilation. This is an absurd notion created by Special Relativity. A person moving on the train could experience the appearance of time dilation (i.e. time going slower for the stationary observer) if there was no 'actual' time dilation.

 

In conclusion I am not convinced that time dilation occurs.

 

Damien

[Tormod]

In conclusion I am not convinced that time dilation occurs.

 

Good. Now write it up in a paper, submit it to a peer-reviewed journal, and receive a Nobel prize. Because it goes against everything that modern physics is based upon, ie the relativity theory.

 

:circle:

[Damo2600]

Hi Tormod,

 

I know the above is rather long winded and who could be bothered reading it. Right?

 

I'll shorten it a bit:

 

How can my time be going 'slower' than yours yet I observe your 'faster' time to be going 'slower' than mine?

 

Can anyone explain this?

 

Damien

[Queso]

wowzers. yeah it's complex but that doesn't mean it's not true.

[Tormod]

Can anyone explain this?

 

In all fairness - it has been explained to you over and over now. Go read "Relativity" by Einstein.

[Damo2600]

This has never been explained to me. In Einstiens paper he explains that this specific observation happens yet he doesn't explain why. He 'sort of' skips over this bit.

 

I understand that, if time dilation occurs, 'your' stationary observation is that 'my' time appears slower. In all fairness when I read it it does make sense. This goes on to suggest that time actually slows down. He does not however state then why from my perspective, in a slower time dilation, I will observe your faster time to be going slower ( edit:slower than mine. that should say)

 

This is the part I am majorly stuck on.

 

Damien

[Eduffy80911]

When a system or inertial reference frame moves at high enough velocity to experience time dilation, all motion within the system slows down, including on the sub atomic level. All interaction including metabolism, decay rates, everything slow down, thus an observer within the system experiences less time. This could be due to the interaction of particles within the system with the ether (if you believe in the existance of an ether). An observer outside the system would see only a snapshot as the system went past. If you put your focus, or your camera, within the system a live feed (viewed from outside the system) might appear to move more slowly than normal, but when you played back a recording made within the system outside the system, motion would appear normal because the recording functions would have slowed down in concert with the inertial reference frame (assuming the recording was done within the system.)

[Damo2600]

Thank you Eduffy for taking time out to respond to my post,

 

You've just described how time dilation would be experienced. This is not however in reference to the question I asked. (By the way apparently they can show time dilation at extremely slow speeds.)

 

My question is prior to your post.

 

Thanks Damien

[Eduffy80911]

That's a tricky one because for you to observe the other reference frame you must rely on photons that have moved from one inertial reference frame to another.

[Damo2600]

1/ I understand the Lorentz Transformation if there is no 'actual'

time dilation.

2/ I understand the Lorentz Transformation if there is 'actual' time

dilation but everything stationary, according to me (moving), is

observable faster.

3/ I do not understand the Lorentz Transformation if I observe your

time to be slower and you observe my time to be slower yet: My

time 'is' going slower and your time 'is' going faster.

 

This has nothing to do with an absolute reference frame. The

(stationary) light bouncing perpendiculary up and down would have to

be observably faster if I was moving, in a straight line,

perpendicular to it i.e. if I am experiencing slower time. The person

standing next to the light bouncing is seeing it move at a stationary

time frame i.e. the speed of light with no time dilation. I'm

experiencing a slower time frame so I would percieve it to be going

faster than the speed of light.

 

I've mulled this over and mulled this over. If number 3/ is correct then there is ABSOLUTELY no way that if I am on the train I would observe this (stationary)

bouncing ray of light to be moving at the speed of light. ABSOLUTELY

no way.

 

If it could be explained to me in a logical sense perhaps I could

accept it. But I've read Einstien's paper and no where within it's

pages does it explain this.

 

1/ 0r 2/ have to be true.

 

Josephine

[quantum quack]

Just a couple of thoughts for what it's worth,

 

Mutual dilation, that is to say the other RF seeing the other RF as always slower than itself is a constant sorce of puzzlement to all who venture in to the world of SRT. I gather from earlier posts that this reciprical dilation has been explained as being due to a lack of simultaneity and the simple fact that SRT tends to impose a rest frame perspective in a two frame universe.

 

This slower than the other is an outcome of this preference for one frame being considered as at rest whilst the other has all the velocity of the two RF's.

 

What possibly would be a better discussion is on how can a RF ever be determined to be at rest, [absolute rest regarding a two frame universe] when absolute rest is not a SRT compliant pheno.

 

I have often wondered why in a two object universe only one object is deemed to have all the velocity when it is impossible to determine either objects velocity and only an equal velocty can be logically assumed.

 

In reality an object with velocity is not able to be considered as at rest, arbitarilly swapping RF's is really only available as a mathematical construct which SRT does rather well.

 

For example the Sun / Earth system. SRT will allow us to assume in our equations that the Sun goes round the Earth and vica versa.

Now of course this is intuitively an absurd position.

 

It could be argued that as SRT is founded on Einstien/Minkowsky spacetime and that to have the sun orbit the Earth would invalidate all spacetime or gravitational consequences. Thus to state that we can asssume that the sun has all the velocity in the system would be invalid. However SRT allows us to make such assumptions and this is some what perplexing. [ If I am incorrect in this premise please correct me]

 

 

 

It is also worth noting that there has never been any evidence in physically observed pheno, that supports a reciprical dilation state.

 

There has been some suggestions about Muon decay but so far this appears to be inconclusive.

 

:circle:

[Buffy]

If I bounce my breasts on a train and somebody is off the train staring at them the time and speed of the bounces is the same for both observers. However the velocity of the train is playing with your head because it appears my breasts are moving further than they actually are.

Josephine,

 

You missed the part in Special Relativity about length contraction going on at the same time as time dilation, so you should realize that depending on your speed, your boyfriend would perceive a your loss of one or two cup sizes.

 

One thing that I think you're really missing in terms of trying to understand this is that *everyting* is in terms of a frame of reference. *You* are always going to experience normal time. *An oberver* will see your time dilate and lengths contract as long as relative motion is high enough. You watching that observer will see time dilate for that observer. These last two sentances are refering to direct observations at the time of movement, which is very hard to deal with in the real world. Actual experiments involving time dilation require agreement on a reference frame and the traveler who moves farther at greater average speed will have an earlier time on their watch when two observers "meet up". E.g. in the atomic-clocks-on-an-airplane example, the airport *is* actually moving, but the airplane moves farther faster, so the clocks don't match when the plane gets back to the airport. There is no such thing as "false" time dilation, and it is never experienced *by you about yourself*, it can only be measured when compared to the local frame of reference and the *specific* observer you're comparing to.

 

Cheers,

Buffy

[Damo2600]

I understand your post.

 

If the Earth is revolving and I am moving counterclock wise to the clockwise movement of the Earth then in actual fact I am going slower than someone stationary to the Earth. If the universe is revolving around earth then I am going faster. If the universe is simulataneously revolving around both of us then neither one of us is going faster velocity wise.

 

However what I am being told is that:

 

if you travel with an atomic clock on an aeroplane then my clock will have been going slower than an atomic clock the stationed on the ground. When you land the plane the clocks are different.

 

This leads me to a further problem.

 

Imaging travelling at 10% of c in a train through an endless field of clocks. You have atomic clocks. Big digital clocks. Pendulum clocks. Round faced electric clocks and any other type of clock you can name. All the clocks are stationary. They are every where and large enough to see.

 

You are sitting comfortably and wonder 'what is the time right now'? You look at you wrist watch and it says 12:00. You then look out the window and it says 12:05.

 

According to Special Relativity the clocks in the field should all say 11:55 because I am observing time of events stationary to me to be going slower. That is totally absurd to me.

 

Damien

[Buffy]

Imaging travelling at 10% of c in a train through an endless field of clocks. You have atomic clocks. Big digital clocks. Pendulum clocks. Round faced electric clocks and any other type of clock you can name. All the clocks are stationary. They are every where and large enough to see.

 

You are sitting comfortably and wonder 'what is the time right now'? You look at you wrist watch and it says 12:00. You then look out the window and it says 12:05.

 

According to Special Relativity the clocks in the field should all say 11:55 because I am observing time of events stationary to me to be going slower. That is totally absurd to me.

Yep! No one ever said it was intuitive! Remember the key here is that *you* see it differently than the stationary viewer and vice versa. There is no "absolute" true time.

 

Here's a site with an interesting set of javascript animations of how it works:

http://www.phys.unsw.edu.au/~jw/time.html

 

Cheers,

Buffy

[Damo2600]

I, again, understander stand the javascript example. I have described this example many times myself in my posts. What this example fails to show however is the opposite viewpoint where the light is bouncing back and forth next to the stationary character.

 

If it could show both POVs with relative and actual time dilation for both characters (with light bouncing next to both charcters) and how that works I might understand. It does not and even Einstien did not show this case I have just described.

 

Damien