Is this Relativity Falsified?

[ronians1]

In your example, if you were on that spaceship cicumnavigating the Earth, the hands on the spaceship clock would be running normally as you see it. From your perspective on the spaceship, you are at rest and the Earth is moving. From your point of view, you are not virtually frozen in time.

 

Just concentrate on the facts of the matter and forget perspectives which are unimportant in this instant. At the virtual speed of light the astronaught would be virtually dead and frozen in time and not in a position to notice anything else which would be equally be frozen in time. Look at the Hafele-keating experiment.

.

But we on Earth see your spaceship clock running much slower than our Earth clocks and, as Swansont pointed out, your heart beating much slower. To us on the Earth, you appear to be virtually frozen in time.

 

This is not relevent

 

at a different rate[/u] than we measure from here on Earth. As strange as this sounds and as hard as it might be to accept it, this is what relativity is telling us.

I don't think so. I know a second on the spaceship would still be a second but each second would take longer to pass -hence slow motion(in this case frozen in time). The astronaught on the spaceship travelling at the near speed of light would be virtually frozen in time. Check this out with you physics teacher if you have one.

 

This imples that time travel is impossible

[Greg H.]

Just concentrate on the facts of the matter and forget perspectives which are unimportant in this instant.

 

And this is exactly why you're failing to grasp this: You see the perspective as unimportant, when in fact, it's at the heart of what GR tells us. From your perspective, your personal clock runs the same speed all the time, regardless of how fast you personally are moving. It is only from the perspective of an observer outside of your frame of reference that any differences will be noticed.

 

 

 

[ACG52]

The astronaught on the spaceship travelling at the near speed of light would be virtually frozen in time. Check this out with you physics teacher if you have one.

 

 

Not from the frame of reference of the ship. On the ship, everything is normal.

 

Get a physics teacher if you can find one.

[ronians1]

It is by using the sleight of hand of FORs that makes time travel seem possible. If you need a frame of reference when none is preferred,

then use the frame of reference of Earth and the spacecraft and they both come out the same.......slow motion.

 

This is fact and reality

[zapatos]

It is by using the sleight of hand of FORs that makes time travel seem possible. If you need a frame of reference when none is preferred,

then use the frame of reference of Earth and the spacecraft and they both come out the same.......slow motion.

 

This is fact and reality

What do you make of this situation where only you are able to uncover facts and understand reality, and all the physicists of the world are apparently dolts?

[Delta1212]

Biological time can't be relative. One can't treat biological systems as if they were inanimate objects surely? Biological systems would have to function in slow motion if clocks tick slower. There is no ther way around for biology. Metabolism is a straight arrow which can only ensure the survival of an organism by working between certain margins.

 

Biology cant just function to a point of view. For a biological system to survive something else must give and that something could be the FOR or Time itself. Biological time is not relative.

Biological time is relative. There is no difference between the matter in a biological system and the matter in a clock except for the pattern it is configured in. That pattern doesn't, in any way, change its relationship with time.

 

Alright, let's say there is an astronaut in his spaceship heading back to Earth from an interstellar mission at a significant percentage of the speed of light. He receives a message from Earth, and, being the intelligent astronaut that he is, works out how long ago they must have sent it to reach him that far away. A few years later, his ship approaches Earth.

 

 

Now, there are two scenarios:

 

In the first one, the astronaut lands on Earth and thanks them for the message they sent him five years ago. In response, Earth tells him, "Five years ago? Why, we sent that a decade ago!"

 

In the second one, the astronaut passes by Earth without slowing down, but Earth sends up a representative to hitch a ride on the spaceship as it goes on to the next mission. The astronaut tells his new crewmate how much he appreciated the message they sent him five years ago. In response, the man says, "Five years? Why, it's barely been half that time!"

 

 

From the FOR of Earth, the ship has been experiencing time at a slower rate. From the point of view of the ship, Earth has experienced time at a slower rate. In the Twin Paradox, the twin in the spaceship isn't younger because he was travelling at lightspeed. He is younger because he synched back up with Earth's frame of reference, and in Earth's frame of reference, he was traveling at (well, close to) lightspeed..

[swansont]

Before I reply to the others let's get this straight:

 

If I got into a spaceship and circumnavigated the Earth indefinitely at the near speed of light, the hands of the spaceship clock would run slow(Hafele-Keating experiment but quicker). Would I or would I not be virtually frozen in time? If not why not? The hands of the clock on the wall of the spaceship would be. Why shouldn't my hands be frozen in time? Are you saying thet biological systems "are not" affected by time dialation?

They most certainly are affected. You were the one asserting that biological systems are not.

 

Things will look like slow motion to an outside observer, owing to the time dilation. By all measures, it will be as if very little time passed on board the spacecraft. Even though the outside observer measures a much longer interval, to the one on the craft, everything seems normal. It matters very much to which frame of reference you are referring at any point in a relativity discussion.

[IM Egdall]

ronians1, I'm gonna give this one last try. I hope it helps.

 

Say you are sitting in your chair reading this. Right now you are at rest. Correct? Ya, you're at rest with respect to the chair you are sitting in and the Earth upon which it sits. But what about the Sun? You, the chair, and the Earth are moving at some 67000 miles an hour with respect to the Sun.

 

Do you feel this speed? No. Why? Because you are moving in (nearly) uniform motion -- hardly any change in speed or direction.

 

And right now you, the Earth the Sun, and the rest of our solar system is moving relative to the center of our galaxy at some 486,000 miles an hour. Yet you don't feel this motion either.

 

Everything in our universe is moving relative to something else. And perspective or point-of-view cannot be brushed aside. It is key to understanding what is going on. From your point of view, you and the Earth are at rest (that's why you see the Sun rise and set). To you, time is running normally.

 

But an observer say at the center of the Milky Way galaxy sees you moving relative to her at 486,000 miles an hour. So she sees you and your clock and your biology and everything else on this Earth moving slower. She measures your time as running slower than hers.

 

There is no absolute time. You must give up this notion. (I teach lay physics courses but please find your own physics teacher who is knowledgable in relativity -- she/he will certainly confirm what we are all trying to say to you here.)

Edited August 6, 2012 by IM Egdall

[ronians1]

Biological time is relative. There is no difference between the matter in a biological system and the matter in a clock except for the pattern it is configured in. That pattern doesn't, in any way, change its relationship with time.

 

Alright, let's say there is an astronaut in his spaceship heading back to Earth from an interstellar mission at a significant percentage of the speed of light. He receives a message from Earth, and, being the intelligent astronaut that he is, works out how long ago they must have sent it to reach him that far away. A few years later, his ship approaches Earth.

 

 

Now, there are two scenarios:

 

In the first one, the astronaut lands on Earth and thanks them for the message they sent him five years ago. In response, Earth tells him, "Five years ago? Why, we sent that a decade ago!"

 

In the second one, the astronaut passes by Earth without slowing down, but Earth sends up a representative to hitch a ride on the spaceship as it goes on to the next mission. The astronaut tells his new crewmate how much he appreciated the message they sent him five years ago. In response, the man says, "Five years? Why, it's barely been half that time!"

 

 

From the FOR of Earth, the ship has been experiencing time at a slower rate. From the point of view of the ship, Earth has experienced time at a slower rate. In the Twin Paradox, the twin in the spaceship isn't younger because he was travelling at lightspeed. He is younger because he synched back up with Earth's frame of reference, and in Earth's frame of reference, he was traveling at (well, close to) lightspeed..

 

Both scenarios are impossible as time travel is impossible. Differential aging would ensure the death of a biological system before it reaches the near speed of light - anything else would be conjecture in the realms of fantasy

 

ronians1, I'm gonna give this one last try. I hope it helps.

 

Say you are sitting in your chair reading this. Right now you are at rest. Correct? Ya, you're at rest with respect to the chair you are sitting in and the Earth upon which it sits. But what about the Sun? You, the chair, and the Earth are moving at some 67000 miles an hour with respect to the Sun.

 

Do you feel this speed? No. Why? Because you are moving in (nearly) uniform motion -- hardly any change in speed or direction.

 

And right now you, the Earth the Sun, and the rest of our solar system is moving relative to the center of our galaxy at some 486,000 miles an hour. Yet you don't feel this motion either.

 

At 486,000mph everything would seem normal - you would have to go much faster before you would start feeling anything.

 

Everything in our universe is moving relative to something else. And perspective or point-of-view cannot be brushed aside. It is key to understanding what is going on. From your point of view, you and the Earth are at rest (that's why you see the Sun rise and set). To you, time is running normally.

 

But an observer say at the center of the Milky Way galaxy sees you moving relative to her at 486,000 miles an hour. So she sees you and your clock and your biology and everything else on this Earth moving slower. She measures your time as running slower than hers.

 

There is no absolute time. You must give up this notion. (I teach lay physics courses but please find your own physics teacher who is knowledgable in relativity -- she/he will certainly confirm what we are all trying to say to you here.)

 

You are making assumptions on a new concept with the old rules(relativity). This is a new concept with new rules, most of which have yet to be formulated.

 

Remember what we are dealing with is actuality- what is happening in reality and not hypothetics. The astronaught twin comes back younger. This is a violation of biology and basic Earthly principles. The only way it can be explained is by using the vehicle of slowmotion

 

Differential aging ensures that time travel is impossible.

 

One must ask oneself what is" actually" happening. Which scenario represents reality?. Biological reality does not change with perspective.

[Delta1212]

Just so we're clear, why do you think these scenarios would kill a biological system? It's very likely that one or both of us is not fully understanding what the other is trying to say.

[ronians1]

The First Postulate of Special Relativity

 

The first postulate of the theory of special relativity states: The laws of physics hold true for all frames of reference. This is the simplest of all relativistic concepts to grasp. The physical laws help us understand how and why our environment reacts the way it does. They also allow us to predict events and their outcomes. Next, measure the time it takes a pendulum to make 20 full swings from a starting height of 12 inches above its resting point. You should get the same results but you don't whether you are standing on the ground or riding on a spaceship at the near speed of light. Note that we are assuming that the spaceship is not accelerating, but travelling along at a constant velocity in space..

 

It is contended that the laws of physics do not hold true for all frames of reference, indeed in the spaceship the pendulum would take much longer to make the equivalent swings owing to time dialation at the near speed of light A second may be a second but that second would take longer to pass.

 

It is contended that matters appear normal (and thus conform to relevitivity theory) only at insignificant Earthly speeds but it is at greater speeds aproaching that of the speed of light that actual dialation becomes apparent and thus the theory falsified.

Edited August 8, 2012 by ronians1

[ACG52]

You should get the same results but you don't whether you are standing on the ground or riding on a spaceship at the near speed of light. Note that we are assuming that the spaceship is not accelerating, but travelling along at a constant velocity in space..

 

 

Why would you think you should get the same results in a gravitational field and in free fall? The laws of physics hold tru for all frames of reference, but you are comparing two different environments. The laws being the same does not mean the same results in all reference frames. Different environmental conditions, i.e. gravity and no gravity, will yield different results when the same laws are applied.

 

It is contended that the laws of physics do not hold true for all frames of reference

By whom?

 

It is contended that matters appear normal (and thus conform to relevitivity theory) only at insignificant Earthly speeds

 

By whom?

[zapatos]

It is contended that matters appear normal (and thus conform to relevitivity theory) only at insignificant Earthly speeds but it is at greater speeds aproaching that of the speed of light that actual dialation becomes apparent and thus the theory falsified.

What makes you believe that the earth is not travelling at near light speed?

[ACG52]

What makes you believe that the earth is not travelling at near light speed?

 

 

In fact, I'm sure it is, relative to something.

[ronians1]

Why would you think you should get the same results in a gravitational field and in free fall? The laws of physics hold tru for all frames of reference, but you are comparing two different environments. The laws being the same does not mean the same results in all reference frames. Different environmental conditions, i.e. gravity and no gravity, will yield different results when the same laws are applied.

 

As we are using "the virtual speed of light as a backdrop", at such immense speed the different environmental conditions are irrelevent - all movement, gravitation etc around earth level can be ignored as they would be insignificant compared to the near speed of light

 

If one was being pedantic one could insist that like was compared with like. But say we substituted a train on a smooth level surface on Earth where gravitation was the same, the clock readings would show the same discrepency except so minute that one would have to probably use a caesium clock. I believe time starts dialating on any movement whatsoever.

 

 

By whom?

 

By me.

[swansont]

It is contended that the laws of physics do not hold true for all frames of reference, indeed in the spaceship the pendulum would take much longer to make the equivalent swings owing to time dialation at the near speed of light A second may be a second but that second would take longer to pass.

 

Are you saying the pendulum which has a period of 1 sec takes longer than 1 sec in its own frame if there's motion? That would seem to imply a rest frame.

 

If not, you appear to have described time dilation as it is, which is consistent with the postulate.

 

It is contended that matters appear normal (and thus conform to relevitivity theory) only at insignificant Earthly speeds but it is at greater speeds aproaching that of the speed of light that actual dialation becomes apparent and thus the theory falsified.

 

But we have experimental evidence, e.g. muon decay and particle accelerator experiments, which show relativity holding for speeds close to c.

[ronians1]

Are you saying the pendulum which has a period of 1 sec takes longer than 1 sec in its own frame if there's motion? That would seem to imply a rest frame.

 

A universal frame of reference

 

If not, you appear to have described time dilation as it is, which is consistent with the postulate.

 

 

 

But we have experimental evidence, e.g. muon decay and particle accelerator experiments, which show relativity holding for speeds close to c.

 

Muon decay and particle accelerator experiments are consistant with the postulate that the laws of physics do not do true in all frames of reference.

[swansont]

A universal frame of reference

Which just happens to be that of the earth?

[Delta1212]

A guy sitting on earth watches a spaceship that he sees as moving at close to c. On the spaceship is a pendulum with a period of one second while at rest. The guy on Earth sees the pendulum move in slow motion.

 

On the spaceship, a guy sees the Earth moving away at close to see. On the Earth is a pendulum with a period of one second while at rest. The guy on the spaceship sees the pendulum move in slow motion.

 

 

Now, for relativity not to hold as you are claiming, one of these guys would have to have a way to determine that he is the one that is really moving and experiencing slow motion. If you can outline a method by which one would be able to detect time dilation, and therefore motion, in their own frame of reference, that would be the way to support your position. Even the most basic method of being able to tell that you are the one who is really moving in "slow motion" would suffice, with the caveat that you must be able to tell without changing your reference frame (that I'd, changing speed or direction).

[MigL]

Consider an equation say y=x .

we say the equation is invariant if it does not change with a Lorentz transform, which is a change in frame of reference ( I hope I' getting the terminology right, its been a while ). An example of invariance in relativity is speed of light=c, which holds true with no changes for all frames.

We say the equation is covariant if both sides of the equal sign change, but X and Y are modified so that the equation still holds true. Covariance in relativity means that as we transform the frame to relativistic speed, distances are modified by time and time is modified by distance ( special relativity was reformulated by Minkowsky and Einstein to reflect this and we normally speak of space-time, not space or time ), but the equation still holds true.

 

So to recap, in relativistic situations, some laws of physycs are invariant and don't change at all,, while some are covariant such that the terms of the equation change, but the equation still holds true.

[ACG52]

As we are using "the virtual speed of light as a backdrop", at such immense speed the different environmental conditions are irrelevent - all movement, gravitation etc around earth level can be ignored as they would be insignificant compared to the near speed of light

 

 

Nonsense.

 

Are you stating that gravity is irrelevent? When you say 'near speed of light', relative to what?

 

By me.

 

Ah, argument by appeal to nonauthority.

[ronians1]

A guy sitting on earth watches a spaceship that he sees as moving at close to c. On the spaceship is a pendulum with a period of one second while at rest. The guy on Earth sees the pendulum move in slow motion.

 

On the spaceship, a guy sees the Earth moving away at close to see. On the Earth is a pendulum with a period of one second while at rest. The guy on the spaceship sees the pendulum move in slow motion.

 

 

Now, for relativity not to hold as you are claiming, one of these guys would have to have a way to determine that he is the one that is really moving and experiencing slow motion. If you can outline a method by which one would be able to detect time dilation, and therefore motion, in their own frame of reference, that would be the way to support your position. Even the most basic method of being able to tell that you are the one who is really moving in "slow motion" would suffice, with the caveat that you must be able to tell without changing your reference frame (that I'd, changing speed or direction).

 

I see what you mean. Thanks.

 

A point I am still confused about is whether the astronaught twin actually experienced slow motion during his journey at the near speed of light. If not how can one actually experience time dialation without its effect on the human body?

 

Consider an equation say y=x .

we say the equation is invariant if it does not change with a Lorentz transform, which is a change in frame of reference ( I hope I' getting the terminology right, its been a while ). An example of invariance in relativity is speed of light=c, which holds true with no changes for all frames.

We say the equation is covariant if both sides of the equal sign change, but X and Y are modified so that the equation still holds true. Covariance in relativity means that as we transform the frame to relativistic speed, distances are modified by time and time is modified by distance ( special relativity was reformulated by Minkowsky and Einstein to reflect this and we normally speak of space-time, not space or time ), but the equation still holds true.

 

So to recap, in relativistic situations, some laws of physycs are invariant and don't change at all,, while some are covariant such that the terms of the equation change, but the equation still holds true.

 

Does this mean that the fact that one individual experiencing the effect of a slow-motion environment (spaceship FOR) in relation to another on Earth experiencing a normal environment does not fulfill the requirements required for proving the laws of physics are different in the two instances?

[swansont]

A point I am still confused about is whether the astronaught twin actually experienced slow motion during his journey at the near speed of light. If not how can one actually experience time dialation without its effect on the human body?

Perhaps because you have not adequately defined what you mean by "slow motion".

 

There is no effect on the human body because the effect is on time itself, and everything in that frame is affected equally. In that frame you see no effect at all from moving at a constant velocity with respect to another frame.

[ronians1]

Perhaps because you have not adequately defined what you mean by "slow motion".

 

There is no effect on the human body because the effect is on time itself, and everything in that frame is affected equally. In that frame you see no effect at all from moving at a constant velocity with respect to another frame.

 

But how does this tie up with Biological systems? In the twin paradox the astronaught twin goes away and comes back years younger. This would present a huge problem for a biological system which metabolises according to its own biological time.

Here we have an independant system wihch relies on moment to moment function. Surely one cannot eliminate a huge wadge of time out of this function without physical compensation and that physical compensation would be slow motion.

Edited August 10, 2012 by ronians1

[swansont]

But how does this tie up with Biological systems? In the twin paradox the astronaught twin goes away and comes back years younger.

No, the twin comes back having aged less because less time has passed. If the twins start out aged 20, one twin returns aged 25 while one on earth is aged 40. (for a gamma of 4). Nobody got any younger; it's that one twin is younger than the other because time passes at different rates in moving frames, and an acceleration identifies a frame as being non-inertial.