# DIY Experement: Time Dilation

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#### Pongo

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##### DIY Experement: Time Dilation
« on: February 17, 2009, 03:14:12 AM »
The experiment:
1: Buy two identical atomic clocks.
2: Find a tall skyscraper.
3: Place one clock at the top of the skyscraper and one in the bottom.
4: Wait.
5: Observe the effects of time dilation.

Explanation:
Place two atomic clocks in a skyscraper, one clock in the top of the tower and one clock in the base.  After a years time, bring the top clock down to the bottom clock (AKA the control clock) and note the difference in time by fractions of a second.

Why did this occur?  The top clock was effectively placed in a very low geosynchronous orbit, while the other clock remained at the surface of the earth.  While both clocks revolved around the earth once per day, the top clock had a longer circle to travel.  Therefore it was moving quicker than the clock at the base.  According to Einstein?s Theory of Relativity, the faster an object moves (the top clock), the slower it appears to pass through time from an outside point of view (the bottom clock).  This phenomenon is known as time dilation.

How does this indicate that the world isn?t flat?  If the world were flat and ever careening upwards rather than revolving, the clocks would have measured identical times because they would both be moving up at the exact same speed.

This experiment not only proves time dilation in respect to Einstein?s theory of relativity, but also is a scientific indicator of a revolving planet!  And the best part?  This experiment is completely repeatable!  Have fun experimenting!

Theory of relativity:
http://en.wikipedia.org/wiki/Theory_of_relativity
http://publicliterature.org/books/relativity/xaa.php

Time dilation:
http://en.wikipedia.org/wiki/Time_dilation

Hafele-Keating Experiment:
http://en.wikipedia.org/wiki/Hafele-Keating_experiment

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#### bowler

• 871
##### Re: DIY Experement: Time Dilation
« Reply #1 on: February 17, 2009, 03:17:48 AM »
This has been done for TV in the UK. Though I predict this thread could be fun.

#### midgard

• 1300
##### Re: DIY Experement: Time Dilation
« Reply #2 on: February 17, 2009, 03:36:06 AM »
1: Buy two identical atomic clocks.

Well this is a bit tricky. The only "atomic" clocks I found don't seem appropriate to me. However, if you don't see anything wrong with using them I will gladly use them for the experiment if you accept the results.

If I give you the details of the height of the tower and it's position will you generate your prediction of the time dilation effects for both the different speed and gravity1?

1. Yes, yes, I know.

EDIT:
I don't think any of these seem appropriate enough either.

However, on this site it did give a pretty good lead - but it put the price at USD 50,390... a little out of my price range at the moment.

EDIT[2]:

Following the lead I ended up here. Unfortunately, I can't find any prices or ways to purchase these. As such I will write to them and ask them to donate two to me so I can find out if the earth is flat or round.

EDIT[3]:

I have also noticed they have a list of distributors. If I am unable to get two machines donated for this experiment would you give me the money so I can buy these and carry out your "DIY" experiment, Pongo?

<Edit by ﮎingulaЯiτy - Fixed for broken links.>
« Last Edit: February 24, 2009, 07:33:48 AM by ﮎingulaЯiτy »

#### Pongo

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• 6753
##### Re: DIY Experement: Time Dilation
« Reply #3 on: February 17, 2009, 03:53:08 AM »
Are you asking me to predict the difference cause by time dilation due to Lorentz transformation and gravitational red shift?

EDIT:
It's important to note that this will not definitively prove the shape of the earth.  It will however indicate that the earth is revolving and not zooming upwards.
« Last Edit: February 17, 2009, 04:07:11 AM by Pongo »

#### Pongo

• Planar Moderator
• 6753
##### Re: DIY Experement: Time Dilation
« Reply #4 on: February 17, 2009, 04:03:31 AM »
1: Buy two identical atomic clocks.

Well this is a bit tricky. The only "atomic" clocks I found don't seem appropriate to me. However, if you don't see anything wrong with using them I will gladly use them for the experiment if you accept the results.

If I give you the details of the height of the tower and it's position will you generate your prediction of the time dilation effects for both the different speed and gravity1?

1. Yes, yes, I know.

EDIT:
I don't think any of these seem appropriate enough either.

However, on this site it did give a pretty good lead - but it put the price at USD 50,390... a little out of my price range at the moment.

EDIT[2]:

Following the lead I ended up here. Unfortunately, I can't find any prices or ways to purchase these. As such I will write to them and ask them to donate two to me so I can find out if the earth is flat or round.

EDIT[3]:

I have also noticed they have a list of distributors. If I am unable to get two machines donated for this experiment would you give me the money so I can buy these and carry out your "DIY" experiment, Pongo?

Yes, perhaps the label "DIY" was a bit of a stretch.  However, if you cannot find some clocks to be donated or borrowed, I promise to buy instant scratch-off's until I win enough money to purchase you a set of clocks.  However, given enough time, and excluding the chances of clock failure, any two identical clocks will work. (enough time = lots and lots)
« Last Edit: February 17, 2009, 04:06:54 AM by Pongo »

#### midgard

• 1300
##### Re: DIY Experement: Time Dilation
« Reply #5 on: February 17, 2009, 04:04:29 AM »
Are you asking me to predict the difference cause by time dilation due to Lorentz transformation and gravitational red shift?

EDIT:
It?s important to note that this will not definitively prove the shape of the earth.  It will however indicate that the earth is revolving and not zooming upwards.

I certainly am asking you to predict the results beyond just "they won't be the same". Surely if this experiment is worth anything you should have to make a reasonably accurate prediction to demonstrate that the effect is due to what you say and not some unexplained phenomena.

• 2347
##### Re: DIY Experement: Time Dilation
« Reply #6 on: February 17, 2009, 04:08:16 AM »
This is already done when GPS, and other, satellites have to be recalibrated

#### midgard

• 1300
##### Re: DIY Experement: Time Dilation
« Reply #7 on: February 17, 2009, 04:09:01 AM »
This is already done when GPS, and other, satellites have to be recalibrated

Isn't this DIY experiment getting even more out of hand now we're talking about satellites?!

EDIT[1]:
Yes, perhaps the label "DIY" was a bit of a stretch.  However, if you cannot find some clocks to be donated or borrowed, I promise to buy instant scratch-off's until I win enough money to purchase you a set of clocks.  However, given enough time, and excluding the chances of clock failure, any two identical clocks will work. (enough time = lots and lots)

I have sent of some emails - hopefully I will get a positive response.
« Last Edit: February 17, 2009, 04:18:12 AM by midgard »

#### Pongo

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##### Re: DIY Experement: Time Dilation
« Reply #8 on: February 17, 2009, 04:20:47 AM »

I can predict for you anything you want, some things with more accuracy, some things with less.  I do however have qualms with your explanation for asking for a prediction, which we will call hypothesis from now on.  While formulating a hypothesis is an important step in the scientific process, demanding a reasonably accurate one is not science at all.  If every scientist was held to such standards then every result that defied the hypothesis would have to be thrown out.  As such, if I predicted that the base clock was moving slower, and it turned out that it in fact was not moving slower at the conclusion of the experiment (indicating a non-revolving earth) then I would have to do away with those results.  Regardless, here are my hypotheses...
Time dilation due to Lorentz transformation: The top clock will be a few hundred nanoseconds plus or minus 100 slower than the bottom.
Time dilation due to gradational red shift:  not applicable.
« Last Edit: February 17, 2009, 04:25:56 AM by Pongo »

• 2347
##### Re: DIY Experement: Time Dilation
« Reply #9 on: February 17, 2009, 04:26:31 AM »
This is already done when GPS, and other, satellites have to be recalibrated

Isn't this DIY experiment getting even more out of hand now we're talking about satellites?!

EDIT[1]:

I'm just saying that it's already happening in the world. I'm not suggesting anyones builds a satellite.

#### TheEngineer

• Planar Moderator
• 15483
• GPS does not require satellites.
##### Re: DIY Experement: Time Dilation
« Reply #10 on: February 17, 2009, 04:54:05 AM »
Unfortunately, the clocks will never read the same time, so this experiment is moot.

"I haven't been wrong since 1961, when I thought I made a mistake."
-- Bob Hudson

#### midgard

• 1300
##### Re: DIY Experement: Time Dilation
« Reply #11 on: February 17, 2009, 05:23:58 AM »

I can predict for you anything you want, some things with more accuracy, some things with less.  I do however have qualms with your explanation for asking for a prediction, which we will call hypothesis from now on.  While formulating a hypothesis is an important step in the scientific process, demanding a reasonably accurate one is not science at all.  If every scientist was held to such standards then every result that defied the hypothesis would have to be thrown out.  As such, if I predicted that the base clock was moving slower, and it turned out that it in fact was not moving slower at the conclusion of the experiment (indicating a non-revolving earth) then I would have to do away with those results.  Regardless, here are my hypotheses...
Time dilation due to Lorentz transformation: The top clock will be a few hundred nanoseconds plus or minus 100 slower than the bottom.
Time dilation due to gradational red shift:  not applicable.

I'm pretty sure I said this experiment, not science in general. Yes, if you predict it would be moving slower and it wasn't then this would stand against you. However, just because it is moving slower doesn't mean it's moving slower for the reason you gave, there could be another explanation. I think your explanation would become more likely if you made a more accurate prediction. Do you want the height and position of the tower I have in mind (I still haven't heard anything back about the clocks being donated yet) or will you stick with your one size fits all prediction?

Unfortunately, the clocks will never read the same time, so this experiment is moot.

Could the clocks keep time accurately enough for this experiment to work? I don't know if that's what you're saying but if they're just not "reading" the same time does that cause a problem if you know the difference to begin with? (I don't know much about... anything really, this includes atomic clocks).

#### TheEngineer

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##### Re: DIY Experement: Time Dilation
« Reply #12 on: February 17, 2009, 04:51:26 PM »
Merely moving one clock to a higher elevation will cause it to experience time dilation.

"I haven't been wrong since 1961, when I thought I made a mistake."
-- Bob Hudson

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#### goldstein

• 150
##### Re: DIY Experement: Time Dilation
« Reply #13 on: February 17, 2009, 05:23:07 PM »
Unfortunately, the clocks will never read the same time.

Isn't that the point of the experiment?
This forum blows spunk bubbles out of its diseased, bleeding ass.

#### TheEngineer

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• GPS does not require satellites.
##### Re: DIY Experement: Time Dilation
« Reply #14 on: February 17, 2009, 07:10:17 PM »
Merely moving one clock to a higher elevation will cause it to experience time dilation.

"I haven't been wrong since 1961, when I thought I made a mistake."
-- Bob Hudson

#### markjo

• Content Nazi
• The Elder Ones
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##### Re: DIY Experement: Time Dilation
« Reply #15 on: February 17, 2009, 07:19:51 PM »
Merely moving one clock to a higher elevation will cause it to experience time dilation.

Engy, are you saying that those clocks couldn't be synchronized once they are placed in position and then measurements of the ongoing time dilation caused by the difference in elevation be measured as the OP proposed?
Science is what happens when preconception meets verification.
Quote from: Robosteve
Besides, perhaps FET is a conspiracy too.
Quote from: bullhorn
It is just the way it is, you understanding it doesn't concern me.

#### TheEngineer

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• GPS does not require satellites.
##### Re: DIY Experement: Time Dilation
« Reply #16 on: February 17, 2009, 08:41:46 PM »
I said no such thing.

"I haven't been wrong since 1961, when I thought I made a mistake."
-- Bob Hudson

#### markjo

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##### Re: DIY Experement: Time Dilation
« Reply #17 on: February 17, 2009, 08:53:47 PM »
I said no such thing.

That's why I asked.  So what were you trying to say?
Science is what happens when preconception meets verification.
Quote from: Robosteve
Besides, perhaps FET is a conspiracy too.
Quote from: bullhorn
It is just the way it is, you understanding it doesn't concern me.

#### Pongo

• Planar Moderator
• 6753
##### Re: DIY Experement: Time Dilation
« Reply #18 on: February 18, 2009, 03:16:00 AM »
If you are unsatisfied with the two clock's integrity, or want to account for time dilation from moving a clock to the top of the tower, you can successfully overcome your concerns by doing one or more of the following things:

1: Synchronize both clocks at the middle of the tower and move one up and one down at the same speed.  This will cause them both to dilate at the same rate if dilation due to movement is a concern.

2: Check and see if time dilation is continuing after placing the clocks in their respective places.  If it is, then something is at work causing the two clocks to become more and more out of sync.

3: Use four clocks total, two in the bottom and two in the top.  This will eliminate the concerns that one clock is malfunctioning if both top clocks respectively measure the same time and both bottom clocks measure the same time.

Also, Midgard is very correct.  This experiment will not conclusively prove the shape of the earth, nor does it prove the earth is spinning.  All it proves is that a clock in the top of a tower will appear to tick slower than one at the base.  The next question though, is why does it do this?  I cited Einstein's theory of relativity as the explanation for the phenomenon.  If someone could demonstrate and prove another explanation for why the top clock would appear to tick slower then the impact that person would make on the scientific community would by truly staggering.  However, what this experiment will indicate, assuming your clocks tick differently, is that the world isn?t moving uniformly upwards.

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#### trig

• 2240
##### Re: DIY Experement: Time Dilation
« Reply #19 on: February 18, 2009, 12:22:34 PM »
OK, so somebody has to do the maths, something the majority in this forum seems too philosophical to do.

• Speed at the first floor: 6378000 meters times 2 times pi every 24 hours. The building is at sea level on the Equator
• Speed at the 100th floor: 6378300 meters times 2 times pi every 24 hours.
• Calculated speeds: 463.821240806 meters per second and 463.843057421 meters per second respectively.
• Percent difference: 0.0047%
• Relativistic effect on a speed of 463.821240806: 1/(1-v2/c2)^1/2
• Relativistic effect: approx 1.0000000000014 or 1 + 1.4e-12
• Difference in relativistic effect between the watches: 1 + (1.4e-12 * 4.7e-5)
• Precision required from the watches: better than (1.4e-12 * 4.7e-5)=7e-17 or seventy parts in a million million million.
• Precision given by the 50,000 dollar atomic clock: 1e-14

You would need a clock one thousand to ten thousand times more precise to do this experiment. And we are still not taking into account the resolution.

Thought experiments are nice, but experimental physics is quite another thing. This is not a DIY experiment, it is not even a nice experiment for a nice little laboratory. I am not sure if it is practical or possible for anyone at all with current technology.

#### markjo

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##### Re: DIY Experement: Time Dilation
« Reply #20 on: February 18, 2009, 01:07:39 PM »
The Burj Dubai just topped out at 2684 feet (818 meters) high.  Would that make the math work any better?
http://en.wikipedia.org/wiki/Burj_Dubai
Science is what happens when preconception meets verification.
Quote from: Robosteve
Besides, perhaps FET is a conspiracy too.
Quote from: bullhorn
It is just the way it is, you understanding it doesn't concern me.

?

#### trig

• 2240
##### Re: DIY Experement: Time Dilation
« Reply #21 on: February 18, 2009, 04:18:17 PM »
The Burj Dubai just topped out at 2684 feet (818 meters) high.  Would that make the math work any better?
http://en.wikipedia.org/wiki/Burj_Dubai
The experiment is so far away from feasibility that even the use of the Everest would not help much. If you go from a setting that requires a clock that is 10000 times more precise to a setting where the clock is still 10 times too imprecise, you are doing nothing.

Maybe you can put one clock on the North Pole and another on the Equator, and then you could do something with clocks with 1e-14 precision, but the design of that experiment is not trivial.

#### markjo

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##### Re: DIY Experement: Time Dilation
« Reply #22 on: February 18, 2009, 04:20:51 PM »
The Burj Dubai just topped out at 2684 feet (818 meters) high.  Would that make the math work any better?
http://en.wikipedia.org/wiki/Burj_Dubai
The experiment is so far away from feasibility that even the use of the Everest would not help much. If you go from a setting that requires a clock that is 10000 times more precise to a setting where the clock is still 10 times too imprecise, you are doing nothing.

Maybe you can put one clock on the North Pole and another on the Equator, and then you could do something with clocks with 1e-14 precision, but the design of that experiment is not trivial.

Spoilsport.
Science is what happens when preconception meets verification.
Quote from: Robosteve
Besides, perhaps FET is a conspiracy too.
Quote from: bullhorn
It is just the way it is, you understanding it doesn't concern me.

?

#### goldstein

• 150
##### Re: DIY Experement: Time Dilation
« Reply #23 on: February 19, 2009, 01:49:13 AM »
http://en.wikipedia.org/wiki/Hafele-Keating_experiment

Quote
The Hafele?Keating experiment was a test of the theory of relativity. In October of 1971, J. C. Hafele and Richard E. Keating took four caesium-beam atomic clocks aboard commercial airliners and flew twice around the world, first eastward, then westward, and compared the clocks against those of the United States Naval Observatory.
This forum blows spunk bubbles out of its diseased, bleeding ass.

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#### trig

• 2240
##### Re: DIY Experement: Time Dilation
« Reply #24 on: February 19, 2009, 08:42:13 AM »
http://en.wikipedia.org/wiki/Hafele-Keating_experiment

Quote
The Hafele?Keating experiment was a test of the theory of relativity. In October of 1971, J. C. Hafele and Richard E. Keating took four caesium-beam atomic clocks aboard commercial airliners and flew twice around the world, first eastward, then westward, and compared the clocks against those of the United States Naval Observatory.
This experiment is, of course, feasible and was done, but has one big difference: while the clocks in this experiment were moving at a speed of almost twice the speed of sound with respect to each other, the experiment in the OP has two clocks barely moving with respect to each other.

Even the Hafele-Keating experiment is for the deep pockets. This is not a DIY in any case.

As a test for the shape of the Earth, the Hafele-Keating experiment is not very good. You can argue that flying in circles, squares or any other shape, on Earth or somewhere else, will produce the same results.

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#### Dr Matrix

• 4312
• In Soviet Russia, Matrix enters you!
##### Re: DIY Experement: Time Dilation
« Reply #25 on: February 19, 2009, 11:23:38 AM »
If you want to test time dilation your best bet will be to build your own mini particle accelerator - relativistic effects have to be taken into account to generate good agreement with results.  In terms of how 'DIY' this is, I would suggest it's more DIY than buying 2 caesium fountains, each of them operated by a team from NPL or NIST or simlar (which is what you'd need for the 10-17 accuracy) and setting them up in a skyscraper.

Quote from: Arthur Schopenhauer
All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.

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#### zeroply

• 391
• Flat Earth believer
##### Re: DIY Experement: Time Dilation
« Reply #26 on: February 19, 2009, 12:22:19 PM »

Also, Midgard is very correct.  This experiment will not conclusively prove the shape of the earth, nor does it prove the earth is spinning.  All it proves is that a clock in the top of a tower will appear to tick slower than one at the base.  The next question though, is why does it do this?  I cited Einstein's theory of relativity as the explanation for the phenomenon.  If someone could demonstrate and prove another explanation for why the top clock would appear to tick slower then the impact that person would make on the scientific community would by truly staggering.  However, what this experiment will indicate, assuming your clocks tick differently, is that the world isn?t moving uniformly upwards.

I am NOT a relativity expert, but your understanding of this phenomenon is way off.

The reason that clocks slow down as they get further away from the Earth is not a consequence of special relativity, it's a consequence of general relativity. It has little to do with the relative speeds they are moving at, it's because gravity is different at different elevations.

If you constructed a massive flat lead plate (say the size of Asia), and floated it somewhere in space motionless with respect to the Sun, you would obtain exactly the same results when doing your experiment on a tower somewhere on that plate.

Matrix and some of the other physics guys on here should be able to corroborate (or correct if I'm wrong).

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#### Dr Matrix

• 4312
• In Soviet Russia, Matrix enters you!
##### Re: DIY Experement: Time Dilation
« Reply #27 on: February 19, 2009, 12:56:46 PM »
It's an interesting question - I'm genuinely not sure which would have a bigger effect at that altitude.  I suppose you can argue that they both scale linearly with radius (instantaneous linear velocity and gravitational potential) so if you're making a differential measurement you'll see them both change by the same amount from ground to top of skyscraper.  Trig seems to like doing maths so I'll let him figure out which is dominant, but my suspicion is that the GR signal will dominate until you're talking about geostationary orbits substantially higher. Meh, I dunno!
Quote from: Arthur Schopenhauer
All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.

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#### bowler

• 871
##### Re: DIY Experement: Time Dilation
« Reply #28 on: February 20, 2009, 02:37:18 AM »
I think the GR effects are greater but maybe only by a factor of a few.

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#### zeroply

• 391
• Flat Earth believer
##### Re: DIY Experement: Time Dilation
« Reply #29 on: February 20, 2009, 07:13:19 AM »
I think the GR effects are greater but maybe only by a factor of a few.

Well, then the experiment would be useless to determine the movement of the Earth, unless you could also prove what part of the effect was from GR and what part was SR.

Also, you certainly don't need something the size of the Burj Dubai to measure this effect. When the NIST moved one of their clocks up one level in their building they had to calibrate it to adjust for relativistic effects. It was in an article at wired.com a few years ago, don't have link handy.