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#46116 11/15/12 03:16 AM
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Richard Wolfson’s “Simply Einstein” is a book I would recommend very highly, but even in this work it is possible to find things that don’t seem to add up – at least to me.

Lets consider three scenarios:

1. (Passengers in an aircraft): Wolfson asks: “Am I moving?” He then answers the question as follows: “By looking out of the window you can justifiably assert that the plane is moving relative to Earth, but that is as far as you’ll get. You’re just as correct in asserting that Earth is moving relative to the plane.” So far, so good; this is exactly what relativity tells us.

2. (The twin paradox, involving a return trip from Earth to a distant star): Wolfson argues that because the occupants of the space ship experience acceleration, whereas those on Earth do not; one can say that the spaceship is moving relative to the Earth, but not the other way round.

Is it just nit-picking to insist that the same can be said of the aircraft in the first scenario?

3. (Spaceship passing Earth in uniform motion): Wolfson explains that because both Earth and spaceship are in uniform motion, each must be able to claim to be stationary, relative to the other, and both must observe the other’s clocks to be “running slow”, relative to their own clocks.

Apart from ignoring the fact that the space craft must have accelerated at some point, relative to something; this does seem to leave one question unanswered. Suppose that when the spacecraft passes Earth, there happen to be two people, one on the ship and one on Earth, who are exactly the same age. When the ship passes a distant star, some time in the future, will there be any difference between their ages?


There never was nothing.
.
Bill S. #46117 11/15/12 03:37 AM
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Quote:
1. (Passengers in an aircraft): Wolfson asks: “Am I moving?” He then answers the question as follows: “By looking out of the window you can justifiably assert that the plane is moving relative to Earth, but that is as far as you’ll get. You’re just as correct in asserting that Earth is moving relative to the plane.” So far, so good; this is exactly what relativity tells us.


if the plane is sitting on the ground , it is moving.
and it is moving faster than the ground.

could two observers look at the watches and see the difference
in time between the two velocities?

and the answer is a definite possible yes!!!

Quote:
2. (The twin paradox, involving a return trip from Earth to a distant star): Wolfson argues that because the occupants of the space ship experience acceleration, whereas those on Earth do not; one can say that the spaceship is moving relative to the Earth, but not the other way round.


the occupants of the earth are also experiencing an acceleration 24/7

and the answer is a predefined possible definite possibility.

Quote:
3. (Spaceship passing Earth in uniform motion): Wolfson explains that because both Earth and spaceship are in uniform motion, each must be able to claim to be stationary, relative to the other, and both must observe the other’s clocks to be “running slow”, relative to their own clocks.



the earth does not travel in uniform motion.
uniform motion requires a straight line.

and the answer is apples and oranges.


Quote:
Apart from ignoring the fact that the space craft must have accelerated at some point, relative to something; this does seem to leave one question unanswered. Suppose that when the spacecraft passes Earth, there happen to be two people, one on the ship and one on Earth, who are exactly the same age. When the ship passes a distant star, some time in the future, will there be any difference between their ages?


and the answer is a most definite absolutely.

the one on earth would be dead , if the spaceship were capable of anything less than lightspeed.

so the one on earth would be dead.

when the one who was on the spaceship traveling less than lightspeed returns to earth he could have the dead ones corpse radio carbon dated to see just how much older he is.













3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
Bill S. #46119 11/15/12 03:38 PM
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Originally Posted By: Bill S.
2. (The twin paradox, involving a return trip from Earth to a distant star): Wolfson argues that because the occupants of the space ship experience acceleration, whereas those on Earth do not; one can say that the spaceship is moving relative to the Earth, but not the other way round.

Is it just nit-picking to insist that the same can be said of the aircraft in the first scenario?


You are correct, the same thing can indeed be said of the aircraft. The main difference is a question of scale. The difference in velocity is so small that the contraction is almost impossible to measure. However, it can be done. The first that I know of was back in the 1960s when Hewlett Packard introduced the first commercial atomic clock. Before that you had to build your own. As a publicity stunt HP took 2 of their clocks and very carefully compared their timing. Then they bought an around the world air line ticket for one of them. When it got back to Palo Alto they compared them again and found that there was a discrepancy in their times that matched Einsteins equations. But you can't make the comparison with a pocket watch.

Bill Gill


C is not the speed of light in a vacuum.
C is the universal speed limit.
paul #46121 11/15/12 03:45 PM
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Quote:
if the plane is sitting on the ground , it is moving.
and it is moving faster than the ground.


Moving relative to what?

Quote:
the earth does not travel in uniform motion. uniform motion requires a straight line.


I did Wolfson no favours by trying to pick out the skeleton of his argument. He did say: "...to the extent that Earth is in uniform motion – and to a very good approximation, it is.."

At least I wasn't nit-picking. smile


There never was nothing.
Bill S. #46124 11/15/12 05:37 PM
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Quote:
Moving relative to what?


everything else , other than the plane.

Quote:
and it is moving faster than the ground.


depending on which part of the plane we wish to measure the speed of , according to the distance from the center of the earths rotation.

suppose the plane is 50 feet tall , the top of the planed is
moving faster than the ground the plane is sitting on.

lets say the distance from the center of the earths rotation to
the ground where the plane is sitting is 4000 miles.


the grounds angular speed is

1047.1975511965977461542144610932 mph

the top of the plane is 50 ft higher than the ground.

the top of the planes angular speed is

1060.2875205865552179811421418568 mph

a difference of 13.089969389957471826927680763832 mph

Quote:
He did say: "...to the extent that Earth is in uniform motion


there is not a single molecule on earth that is in uniform motion.

the spaceship could be made to travel in uniform motion , but it would be extremely hard to accomplish , as it would be affected by all sources of gravity.

if relativity is proven on the basis of falsities then that proves that relativity is false also.





3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
Bill S. #46125 11/15/12 06:00 PM
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Originally Posted By: Bill S.

3. (Spaceship passing Earth in uniform motion): Wolfson explains that because both Earth and spaceship are in uniform motion... space craft... spacecraft... ship... ship


So your spaceship doesn't have a name? Doesn't seem like much of a spaceship if it doesn't have a name. Have you ever heard of a spaceship without a name.

"Star date 38759385x9494, Captain James T. Kirk of the starship, eh, crap, my, this is a predicament, screw this, where that green woman at?"

My ship in my thread has a name, the 'HMS Blowme' and her sister ship 'Bob'. My thread has almost 300,000 views. Your thread? Not so much. Maybe if your ship had a name you could get some views, otherwise you are just practicing typing.


What? I've a drawing I want here. How I do that?
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hey Marchimedes where you been?

what we need in this forum is a little reality , could you be just the person to supply that edge?

how's your sister doing?

welcome back


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
paul #46127 11/15/12 06:18 PM
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Originally Posted By: paul
hey Marchimedes where you been?


In the cave where I keep a guy for screaming at. My flash drive died and imageshack shrunk all my images so I'm starting over.

Quote:
what we need in this forum is a little reality , could you be just the person to supply that edge?


Hey now, do you see me saying things like "space/time", "curvature of space", "multi demensional" or "vote for Obama, he won't take you cash and give it to someone else?"

Of course I'm that guy, I say things like "if you take a monkey and materialize him in a empty universe and that monkey flings some feces the monkey and feces will travel away from each other, but eventually gravity will overcome their inertia and monkey and feces will one day be reunited."

Now THAT'S science.

Quote:
how's your sister doing?


She's fine, thank you.

Quote:
welcome back


I posted a thing in my thread a couple of weeks ago.


What? I've a drawing I want here. How I do that?
Bill S. #46128 11/15/12 06:39 PM
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Originally Posted By: Bill S.
Richard Wolfson’s “Simply Einstein” is a book I would recommend very highly, but even in this work it is possible to find things that don’t seem to add up – at least to me.

Lets consider three scenarios:


3. (Spaceship passing Earth in uniform motion): Wolfson explains that because both Earth and spaceship are in uniform motion, each must be able to claim to be stationary, relative to the other, and both must observe the other’s clocks to be “running slow”, relative to their own clocks.

Apart from ignoring the fact that the space craft must have accelerated at some point, relative to something; this does seem to leave one question unanswered. Suppose that when the spacecraft passes Earth, there happen to be two people, one on the ship and one on Earth, who are exactly the same age. When the ship passes a distant star, some time in the future, will there be any difference between their ages?


Originally Posted By: Mike Kremer

Mike Kremer attempting to answer Scenario 3.

Any sort of continous movement will make you appear younger than some-one at rest.
Regarding the two people ..one in the space craft and the other on Earth, the only way they can be guaranteed to be born at the same time, is for both of them to be born in the same place.

To satisfy this, they must both be born in the moving rocket. One of them parachutes to Earth, as the rocket flys by.

The other way around acceleration would have to be added into the age equation.

Due to the rockets continous (and steady) movement, one can assume that
the person in the rocket ages slower than his twin.

But the only way to prove this differences in ages, would be for the rocket (without slowing) to return towards Earth in a wide circle, and drop off its passenger by parachute, as it re-passes.



.

.
"You will never find a real Human being - Even in a mirror." ....Mike Kremer.


paul #46129 11/15/12 06:44 PM
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Not sure you know how to reply to thjese type of questions Paul.
No need to talk about light speed and dead corpses

Just substitute Atomic clocks in place of the two people.


.

.
"You will never find a real Human being - Even in a mirror." ....Mike Kremer.


paul #46130 11/15/12 09:57 PM
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Paul, you talk of the plane and the ground moving relative to the centre of the Earth; but the centre of the Earth is rotating as well, so both are stationary relative to the centre of the Earth.

The further an object is from the centre of the Earth the faster it moves, relative to some object stationary in space, but how do you establish that something is stationary?


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Hi Marchimedes.

Quote:
Maybe if your ship had a name you could get some views, otherwise you are just practicing typing.


You viewed it, I would count you as a person, do your self the same favour. smile


There never was nothing.
Mike Kremer #46132 11/15/12 10:07 PM
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Originally Posted By: Mike
Any sort of continous movement will make you appear younger than some-one at rest.


Only if you can establish that you are the one moving, which seems to require non-uniform motion.


There never was nothing.
Mike Kremer #46144 11/17/12 04:03 AM
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I dont think that atomic clocks would be the ideal clock to use.

atomic clocks seem too vulnerable to pressures.

acceleration causes pressures.

this might be why the atomic clock in the plane did not show
the same exact time as the atomic clock on the ground.

the atomic clock ( WORKS ) in the plane was undergoing more angular acceleration than the one on the ground.

I could be wrong , but figure the odds of that happening.


put a atomic clock on a balloon that will not be moving relative to the ground , the higher it is the faster it is moving although it is tethered to the same spot beneath it on the ground.

let it stay up there for a week.
the two times should still be different.

even though the clock high in the atmosphere never really moved relative to the ground , it only went up.






3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
Bill S. #46145 11/17/12 04:14 AM
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Quote:
Paul, you talk of the plane and the ground moving relative to the centre of the Earth; but the centre of the Earth is rotating as well, so both are stationary relative to the centre of the Earth.


no I was talking about the plane moving relative to the ground.

Quote:

The further an object is from the centre of the Earth the faster it moves, relative to some object stationary in space, but how do you establish that something is stationary?


I dont think that a stationary object will ever be found.

even if you do determine that a certain object is found to look stationary , its atomic structure will always be moving.

electrons n such

since a stationary object is impossible to find especially here on the earth , any relative object is not stationary to any relative object.

theres no such thing as a stationary object.

theres no such thing as time either...


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
paul #46146 11/17/12 04:48 AM
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I dont think the reason for any time dilation is due to velocity!!!

I think its due to acceleration only.

either around a curve or in a straight line.

all the test have been conducted circling the earth
was there any time dilation on any of the moon missions?


3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
paul #46148 11/17/12 03:58 PM
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Quote:
…a balloon that will not be moving relative to the ground


Quote:
no I was talking about the plane moving relative to the ground.


Reasoning in two directions at once may work well in politics, but how good is it in science?


There never was nothing.
Bill S. #46149 11/18/12 04:07 AM
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Quote:
if the plane is sitting on the ground , it is moving.
and it is moving faster than the ground.


plane and ground

Quote:
no I was talking about the plane moving relative to the ground.


plane and ground

Quote:
…a balloon that will not be moving relative to the ground


balloon and ground

Quote:
Reasoning in two directions at once may work well in politics, but how good is it in science?


how did you compose the two different directions?

not only can we not understand you guys , Im not sure how you guys can even understand yourselves.

when something is moving it has both direction and speed.

the plane is sitting on the ground , both the plane and the ground have the same direction , but the top of the plane
has more speed that the ground has.

the top of the plane has a speed 13 mph faster than the ground.

its not that hard to figure out.

still I introduced the balloon to try and give you a mental
picture of the differences in speed between the two.

BTW ... and Im surprised you didnt catch it.
I had the calculation wrong.

there was only a .00247 mph difference in speed between the top of the plane and the ground.

if 50 ft shows a difference in speed of .00247 mph , then a balloon at an altitude of 31 miles...

would show a difference of 8 mph speed between the ground and the balloon.

that's not really a lot of difference in speed , but because
in my opinion time dilation only occurs during acceleration the two clocks should register different times even though the clocks are not even moving away from each other.

they only have different speeds ( angular acceleration ) due only to there distance from the center of the earth.











3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
paul #46150 11/18/12 12:46 PM
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Quote:
BTW ... and Im surprised you didnt catch it.
I had the calculation wrong.


Paul, I am unlikely to spot your calculation error; I tend to trust your calculations. It’s only your reasoning that sometimes gives me problems.

My reference to two directions didn’t refer to directions of movement, but to directions of argument. You seemed to be saying on the one hand that the plane was moving relative to the ground, and on the other, that the balloon was not moving relative to the ground. Can both be true?


There never was nothing.
Bill S. #46151 11/18/12 01:25 PM
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Quote:
You seemed to be saying on the one hand that the plane was moving relative to the ground


YES !! the top of the plane is relatively moving faster than the ground.

you dont have to use the center of an object you can use any point of the object when calculating the angular velocity
of a point on the object relative to any other point on the object.

aircraft use two ways of measuring speed.

air speed and ground speed.

air speed is the measurement of the aircraft speed.
ground speed represents the actual displacement of the aircraft at ground level.

air speed is always greater than ground speed.


Quote:
and on the other, that the balloon was not moving relative to the ground. Can both be true?


absolutely !!

http://en.wikipedia.org/wiki/Motion_(physics)

consider a record on a turntable , the outer edge of the record
will have a greater angular velocity than the center of the record.

so relative to the grooves of the second song on the record the grooves of the first song on the record will always have a
greater angular velocity , when the record player is turning
the record that is.






3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.
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