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Ric Offline OP
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During a recent trip to the bookstore, I picked up a copy of A Brief History of Time by Stephen Hawking. One passege I read confused me a bit...

Another prediction of General relativity is that time should appear to run slower near a massive body like the Earth. This is because there is a relation between the energy of light and its frequency (that is, the number of waves of light per second): the greater the energy, the higher the frequency. As light travels upward in the Earth's gravitational field, it loses energy, and so its frequency goes down. This means that to someone high up, it would appear that everything down below was taking longer to happen. This prediction was tested in 1962, using a pair of very accurate clocks mounted at the top and bottom of a water tower. The clock near the bottom was found to run slower, in exact agreement with general relativity. Consider a pair of twins. Suppose that one twin goes to live at the top of a mountain, and the other stays at sea level. The first twin would age faster than the second. Thus, if they met again, the first one would be older than the other. In this case, the differance in ages would be small, but it would be much larger of one twin went for a long trip in a spaceship at nearly the speed of light. When he returned, he would be much younger than the one on Earth.

At first, he says that the clock at the top of the tower, (Furhter from Earth's gravity), is moving faster than the one nearer the bottom (Closer to Earth's gravity), and the twin in the mountains ages faster than the one at sea level. But then he says that If a twin went into space (Further from Earth's gravity), he would be younger than the one on Earth (Nearer Earth's gravity). Why doesn't the one who goes into space age faster? is there something here I missed? Any help would be appreciated...


"The first Human who hurled an insult instead of a stone was the founder of civilization." -Sigmund Freud
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Take Earth as a Gravitational Lense for the Observer in Space.Let the events happening on Earth be known by fastest possible means i.e Light.(As in classical GR)
Then it becomes obvious that light will suffer a similar fate as it comes out of it.
Hope that answers your question.

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So why would the person who went to live in the mountains be older? Wouldn't he be younger? This is the part that confuses me...


"The first Human who hurled an insult instead of a stone was the founder of civilization." -Sigmund Freud
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jjw Offline
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DKV;
your comment leaves me wanting something smart.

To the Poster:

Supoose all things next to the Earth are traped.
All physical things next to any large mssive objects are trapped. If you want to formulate a theory that tries to explain that- then don't waste your time here, there are no takers all minds I have triggered so far are closed except for Pasti that seems to have left the room.
jjw

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DKV:

I have been one of your few friends on this silly make believe Forum.You do try my patience and my understanding. As far as I know I am the only person speaking english that has offered a REASON why light traveles as it does here at the Earths position.

Why when involved with common place issues do you feel compelled to throw light into the issue?
this does not compute in real time? I think you are trying to comprehend unworkable stuff.
Love and cheers;
jjw

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Jim,

I think he's talking about two different things.

1. Differences in time due to gravity - twin on mountain.

2. Differences in time due to travelling near light speed - twin in space.

Blacknad.

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Thanks Blacknad:

Your better at this interpretation than I.
I think I am running a little tired.

DKV, try to be a little more fcused, it will help.
jjw

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Thanks JJ ..
I think it is the time for commoners to understand the implications of what they are doing.Knowledge if put in a more comprehensible form serves the Humanity.


" As light travels upward in the Earth's gravitational field, it loses energy, and so its frequency goes down. This means that to someone high up, it would appear that everything down below was taking longer to happen."

So why would the person who went to live in the mountains be older? Wouldn't he be younger? This is the part that confuses me...
REP:Take it this way. let 0 and 1 be transmitted ,to someone on Mountain ,one after the other with some time difference.As the Mountain legend observes slowly(with respect to Information on Earth). His observed time difference is larger.Things are happeing slowly with respect to Earth.However he himself experiences Time as real and Normal..
Now when he decides to come back to Sea Level ... he has some information about earth. When he comes back with this Information it must be consistent with his previous observations which was natural and therefore he has no option but to see them younger than himself.And for Sea Level inhabitants he will be the grand old man.. with extended life probably;-)

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Ahh ok I get it now. Thanks everyone.


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Time doesn't really seem to be a constant in the universe, maybe time is something that works fine on a small scale (relatively) such as our earth, but not in the universe ?


**newsflash! the flight of the Bumblebee doesn't defy the laws of science after all! makes me wonder what else is possible that we may think defies science now but doesn't?*... and the Bumblebee still flies..
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Time is a complex beast to understand.
Refer to What is Time?
With respect to Universe, Time is a normalized Dimension.. and can always be measured using some means.It doesnt vanish.
Pure Spatial existence is not possible.

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When I say not possible it means within the definition of existence.

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Take your statements about time and rewrite them naming another physical dimension. Say for example height.

Does the statement:
"Height doesn't really seem to be a constant in the universe, maybe height is something that works fine on a small scale (relatively) such as our earth, but not in the universe?"

Nonsense. Perhaps it would make more sense if you sustituted "Length" or "Width"? No. Not with them either. Time is just a dimension. Nothing more ... nothing less. Thus your statement is should be reconsidered.


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Time is a periodic understanding of Events or in other words it is a linearized dimension of Thought to understand essentially non-linear sequence of events in Universe.
Just as scale tries to construct Universe spatially.No matter how smart is the choice of instrument or thought, a physically identity never gets exactly replicated.

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Correction :
physically identity should be read as Physical Identity.

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Correction: Please seek pyschiatric support services.


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Take your statements about time and rewrite them naming another physical dimension. Say for example height.

Does the statement:
"Height doesn't really seem to be a constant in the universe, maybe height is something that works fine on a small scale (relatively) such as our earth, but not in the universe?"


Hi Dan,

Not disagreeing with your overall point, but I thought there was a difference with time and other dimensions. Time has a direction that doesn't seem reversible on a macroscopic scale. Other dimensions don't seem to have direction with similar properties.

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You are correct. If it actually exists, then in the sense that mention, it appears to be different.

But keep in mind that our best theory makes no reference to height, width, length, or time as independent isolated entities. Einstein referred to spacetime. And no one has come up with a better, more consistent, explanation since.

My point in my response is that it is seemingly nonsensical to pull out any single dimension from "spacetime" and think it has any real meaning.

Can one have length without time? Can one have time without height? I would argue not in our universe as we understand it.


DA Morgan

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