Janus

OOPS! I might need "Xirb" to make my point. I will edit that post.

 

Xirb shows up in a space station that's twice the radius as Earth. He's seat belted at the equator and moving same speed as Bob so he feels half the force. He undergoes half the acceleration.

 

Are Bob and Xirb the same?

 

How fast is Zach moving?

According to your post, Zach is sitting at the North pole of Earth 3, so he wouldn't be moving at all wrt Bob, who is sitting at the North pole of Earth 1.

These are two I find interesting. They are at the same speed and if you blindfold them they feel the same way. They cover the same distance. I would have thought they were "tied".

 

 

If Earth 3 shows up at twice the mass and twice the radius as Earth 1 with "Zach" at the North Pole and "Yuri" seat belted at the equator at what rate of spin does it become interesting as per your side note?

The interesting part is that Zach and Chuck will show equal time dilation.(Though Zach will feel half the g-force that Chuck does.)

I actually assumed no equatorial bulge (maybe we need exotic planet material as well or we end up with a pancake)

 

What difference would this make to the order?

Due to the way the problem was set up, I also assumed no equatorial bulge. (so that Bob, Dave and Frank all traveled in circles of equal radius. )

Archie shows no SR or Gravitional dilation

Bob only shows SR dilation (even though he is accelerating, this acceleration adds no additional time dilation.

Chuck shows only gravitational dilation, but it will be greater than the SR dilation shown by Bob.

Dave shows the same gravitational dilation as Chuck and in addition the SR dilation of Bob.

Edgar shows the only gravitational dilation but it is greater than the combined gravitational and SR dilation's shown by Dave.

Frank shows the gravitaional dilation of Edgar in addition to the SR dilation shown by Bob and Dave.

Gus shows only SR dilation due to his instantaneous speed at any given moment, but his average velocity will be high enough to show a greater time dilation than any of the others.

On a side note, an interesting result occurs if Earth 2 has both twice the mass and twice the Radius as Earth 1

how can gravity equal acceleration. it is same thing as saying magnetism equals accerleration does it not?

 

No, it is not. The equivalence of gravity and acceleration is due to the equality of 'gravitational' mass and 'inertial' mass(if I increase the gravitational mass of an object so that it attracts another mass more, I also increase its inertial mass and thus its resistance to acceleration, by the same factor). There is no such equality with magnetism. I can increase or decrease the magnetic field of an object without causing the same increase or decrease in its inertial mass and vice-versa. (I can increase the force of the magnetism of the object without increasing its resistance to acceleration.)

If someone (I couldn't do it) were to show the Bible to be credible as a historic document in many other areas then would you count that as evidence (albiet very weak)?

No more than I would count the fact that the movie Titanic accurately described many real events that took place on that ship as evidence that the characters of Rose and Jack actually existed in real life.

I know I know' date=' more questions. But I thought of this:

 

Assume two clocks are ticking at different rates due to general relativity. Let's say they are in a direct line of sight. Over a period of 1000 years, one clock accumulates 1 extra minute. Both clocks are brought together, one is a minute fast. Shouldn't the one that's a minute ahead see a different position of the sun?

[/quote']No, for it, it just took a longer time for the sun to reach the same position that the slower clock sees the sun at.

Example: instead of 1000 years, make it 1,440,000 years. In that case, the faster clock will record 1,440,000 years and one day. This does not mean that it will see the sun make one extra trip around the Sun. It will see the sun make the same 525,600,000 trips that other clock does, it will just record that it took 1,440,000 years and one day to do so. IOW, for it, a Solar day is longer than 24 hrs.

I used to believe in the philadelphia experiment was real' date=' but now I doubt that it was real.

 

It is possible tha some sort of smoke screen was being tested or something of that sort, an accident happened and whatever they were testing generated enough heat to melt some of the steel decking plates.

 

[/quote']

More likely it was just a mish-mash of unrelated bits and pieces thrown together to weave a tale.

 

One was the de-guassing of ships, a standard practice at the time. This made them non-magnetic and thus "invisible" to magnetic mines and torpedos. This involved wrapping the ship in cables and running alternating current through them.

 

Also, around that time the Navy was testing a new high frequency generator on some ships. This generator was known to produce corona discharges.

 

Add the fact that Tesla was known for working with high-frequency coils.

 

Put them together, shake, and out comes a story about how the Navy made a ship disappear using the theories of Tesla.

I ran into an interesting question, if you move at .999C then time is moving extremely slow for you, so if you tried to check your position say relative to several stars, wouldn't it appear as if you had moved faster than the speed of light?

As pointed out time runs slow for you only as measured by someone who measures you as moving with respect to them.

Now, from their standpoint it means that your clock will accumulate 1/5 of a year while you travel the distance from earth to Alpha Centauri (4.3 ly), while their clock accumulates 4.3 years.

From your viewpoint, your clock will also accumulate 1/5 y, but not because your clock ran slow, but because, due to length contraction, you will measure the distance between Earth and Alpha Centauri as only being 1/5 ly, which you traveled at .999c

wow, thats big, what detail is the hubble able to resolve then, I always thought that the hubble had a good 20 kilometer resolution

The Hubble has a resolution of .1 arc-secs.

yeah, I was thinking more of a space telescope, I've seen the hubble images of pluto and like yourdadonapogos said they look pretty much like giant pixels

It would take a telescope with an aperture of about 32,000 in. to resolve objects as small as 5 km on the surface of Pluto.

Well I wouldn't go as far as to say relativity is wrong. I like relativity.

 

But I'm doubting that you can measure the speed of a distant star by studying it's light spectrum' date=' as light can't be subject to a doppler effect as it will always leave is source and reach it's destination at a set speed irrelevant of the motion and position of each of the the two bodies...?

 

Tell me if I'm being stupid or just ignorant.[/quote']

 

Let's see if we can clear iy up for you. light is subject to Doppler shift for the very reason that its speed is invarient for all observers.

 

First consider the following animation. It shows a source located between two observers (the red and blue dots) The expanding green rings represent lightwaves being emitted by the source. Note that the rings expand in perfect circles at c from the point of emission. The first light wave hits both the red and blue dots at the same time.

 

 

Now consider the second animation which shows the situation when the source has a relative velocity with respect to the observers. The first part of the wave is emitted. It expands out as a circle at c and hits the red and blue dots at the same time (as it did in the above animation). An instant later, the next part of the wave is emitted and also expands out as a circle at c. But in the intervening time, the source has moved with respect to the the observers, it is closer to the blue observer than the red observer. Thus this partr of the wave will take less time to reach the blue observer than the red observer (the blue observer will see these parts of the wave arrive closer together than the red obsever will). The pattern repeats for each successive part of the wave.( note that each successive part of the wave also expands in a perfect circle at c from its emission point relative to the blue and red dots.) As a result, the blue observer measures the light at a shorter wavelength and higher frequency and the red observer measures a longer wavelength and lower frequency.

 

 

Note that all this requires is for the source to have a velocity with respect to the observers and that the observers measure the speed of light as a constant with respect to themselves.

*has headache*

 

But the speed of sound waves is changable' date=' and it *is* physically possible to run faster into them.

 

What I don't get: Is it physically [b']impossible[/b] to run faster into light waves because light speed is constant no matter how fast you move?

 

*finds a corner to sulk in*

But you don't need to run into faster light waves to see a doppler effect any more that you need to run into faster sound waves to hear a doppler shift.

If I'm standing on the train platform on a windless day and someone on the platform yells at me, the sound travels at the speed of sound in air towards me. If a train approaches and blows its whistle the instant it passes that person, the sound from it will travel at the same speed as the yell (they will both reach me at the same time). The train whistle will be doppler shifted however.

If we found that Gravitons existed' date=' could their anti-particles impose anti-gravity?

 

[/quote'] Nope, because just like photons, gravitons would be their own antiparticle.

you have to think long term. they go faster, it just takes a while. rockets use all of their acceleration in a short time. ion engines have steady acceleration.

To say that Ion engines "go faster" is a bit of a misnomer. They are just more efficient due to the fact that they have higher exhaust velocities than chemical rockets, which means that they can reach higher velocities with the same reaction mass to payload ratio. Oh, and by the way, Ion engines are still rockets as they use the action/reaction principle for propulsion.

There is a better system on the drawing board, called the VASIMR (VArible Specific Impulse Magnetohydrodynamic Rocket) It could produce even greater exhaust velocities than the Ion engine and more thrust (producing better acceleration).

um no

Um no what?

Have you even done the math?

 

. and no' date=' it isn't impossible. a good ion engine could get to a significant fraction of the speed of light [/quote']

 

Maybe not theoretically impossible, but on the practical side: An ion engine would require on the order of 1.147 x 10^26 kg (About the mass of Neptune) of reaction mass for every kg of payload to reach even 1% of c.

Janus

Post: 88

 

Isn't your sphere S a spaceship? Nevertheless in the sphere S you can also have time t' date=' equal to time t in sphere S':[/quote']

 

I have no sphere S or sphere S'. I have frames S and S'.

I have one spaceship/sphere, to which I did not give any designation. The animations show this same sphere and the same light pulses but as seen from either S or S'.

 

Post #83 show these events according to S, and Post #88 shows these events according to S'.

Any comments to animation? In the animation (3) the light pulse of S appeared too quick' date=' but generally, I think, it's clear.

 

Swansont, you repeated many times, that according to SR...

 

You agreed with three times, for me this is important and enouph. I understood at once, that three times in a spaceship for you is not a nonsence: a cockpit can have 9:00 AM, a restroom can have 13:00 AM, a dining room 18:00 AM, as for you this is ok. [/quote']

 

As determined by someone to which the spaceship is moving this can[i/] be true.

 

Provided that by this one means that if, As determined by someone in the ship, clocks at these three positions all show the same time at any given instant.

 

Then, according to the person that the ship is moving with respect to, these three clocks at any given instant could read 9:00 , 13:00 and 18:00 (For the differences to be this large the ship would have to be very large and moving at a high velocity.)

 

This is not nonsense, it is a consequence of living in a Relativistic universe, in which the concept of simultaneity is not absolute, but relative.

Now it's Ok' date=' you said times t1,t2,t3 difference is misapplication of postulates [06-27-2005, 09:14 PM']. Now, pls develop, how we could simultenously have three different times in a spaceship? . Decipher pls:

t1 - we can see it turning the head to the direction ct1;

t2 - we can have it turning the head to the direction ct2;

t3 - we can have it turning the head to the direction ct3.

So, time is where in our heads? On our watches?

Then, if there would not be light return, what time T will you have?

And ridiculous exp.:

how twins should behave to dilate time t3, to hold the head to direction ct3 20-100 years?

To any observer traveling with the ship, this is what happens:

No matter what direction he is facing.

The stars are there, it is just the they are too dim to be seen with the exposure used. The main objects in the picture (planet etc) are so bright compared to the stars, that the camera setting is such that the stars don't show up.

You see the same effect if you go out and look at the night sky during a moonless night compared to a night with a full moon. During a full moon you'll see a lot fewer stars than on a moonless night. If the moon were a little cloeser to the Earth, it would be bright enough that when you looked at it, you wouldn't see any stars at all.

Here is an animation that shows what happens according to an observer in S for which the ship is moving. The white dots are the light pulses, the yellow lines are the path that the pulses follow with respect to S' the green lines show the paths the pulse's take with respect to S'(the ship}

Yes' date=' I was inattentive. Sorry.

But it is also all your fault and inattentiveness.

I many times asked people to discuss the picture

http://www.rainbow-calendar.hotmail.ru/7

I was thinking you have started discussing it.

 

In this my picture light (3 pulses) was shot NOT in the moving sphere S', but vice versa in S. Sphere S' is catching up with these three light pulses.

Relative distances seen [by the moving observer'] BETA1, BETA2, BETA3 should be divided by C to receive times, different from each other.

CONCLUSION of the picture is: we have three times in one spaceship.

 

Your discussion is different, but nevertheless, sorry:

your distances ct1 and ct2 are different,

your distances ct1' and ct2' are the same.

 

From Newton views: you cheat with C in ct1, because there should be relative speed instead of absolute, meaning vector C + vector V...

Plus you cheat with gamma-factor... Nevertheless, what I have scooped, that you apply to relative distances ct1 and ct2 absolute speed C. So, pls understand my "7.png", divide relative BETA-distances by C and receive 3 times.

 

Following my 7.png, I misunderstood you. As I followed your and Swansont thoughts, you are trying to say that ALPHA distances can have gamma-factor and beta-distances not. This means that you do not "allow" me to divide beta distances by C and receive their times, so we should use only alpha times + only gamma-factor.

 

As for your experiment, pls be specific and slow.

Try to imagine in the sphere S' three light pulses, do not return them back. Compare distances ct1, ct2 and ct3, compare distances ct1', ct2' and ct3'.

In sphere S' times t1', t2', t3 are equal, in the sphere S times are different.

So in one sphere three different times. This is the problem, not that one time, you have derived, having inserted gamma-factor.

 

In S they do not. It means that "at the same time" is different for S' than S. this is a result of living in a Relativistic Universe rather than a Newtonian one.

 

 

 

 

PLS DELETE YOUR MESSAGE SEE NEXT PAGE,

COMPLETE MISUNDERSTANDING,

I did not ask you what the speed [math]\gamma Y \cos \alpha[/math] is?

And the speed gamma*Y*cos Alpha proves that the distance is not simply Y' date=' it should be gamma*Y.[/quote']

To which I asked what speed[math] \gamma Y \cos \alpha[/math] you were talking about, since there is no such speed in the example.

 

 

I told that distances ct1 and ct2 are [gamma * Y]... in your views as ALPHA distances for the moving outsider.

ct1 and ct2 are distances the light travels in S before it hits the sphere.

They contain gamma factor, which you do not want to assign to insider's [math]Y[/math].

because that is not what relativity predicts. If you wish to discuss Relativity you must first learn it, something you've obviously have neglected to do.

Let's go further.

As you poorly showed BETA distance and angle BETA at which outsider sees the light,

I stand by my images, as they are accurate. If you cannot see that, then that is your problem.

let's use the picture

http://www.rainbow-calendar.hotmail.ru/7

Distances to 3 light pulses viewed by the moving otsider, that is BETA distances, are different and if divided by C, they will produce times BETA. So why you assign time ALPHA of the distance [math]\gamma Y[/math] which the moving outsider does not see to these three cases of times BETA.

 

I start out with the assumption that the light is emitted at angle Alpha as seen by the inside observer. I then can calculate the path the light will take with respect to the outside obserever, based on that assumption and the velocity v and knowing the speed of light.

Alpha distance cannot be seen by the moving ousider, so you have no rights to assign gamma factor to the alpha distance this outsider does not see.

one does not have to see something to know that it is true. I didn't have to be around 2,000,000 yrs ago to see the light leaving the Andromeda galaxy to know that the light from it reaching the earth now left it 2,000,000 yrs ago. Thus just because the Outside observer doesn't see the light traveling at angle ALPHA does not mean he cannot know that the light travels at angle alpha as seen by the inside observer.

 

You said contraction is possible, when it is seen, but distance ct1 or ct2 or gamma*Y cannot be seen by the moving outsider; apply your reason to beta distances. He sees light at angles beta, which are different.

OF course the outside observer in S can see ct1 and ct2 As these are the distances the light travels as seen by him by definition!

Sure, I could have determined angle BETA and worked from that, but to determine angle BETA, I have to start from angle ALPHA and determine it from that. Or conversely, I could start with Angle BETA and derive angle ALPHA from it. Either way you go,the two angle are co-dependent.

 

Another question, why beta distance [math]Y\sin\alpha[/math] is mentioned without contractions? If you do not apply contractions to beta distances, then do not apply time induced by these contractions.

[math]Y \sin \alpha[/math] is measured along a line perpendicular to the line of relative motion, Length contraction only applies to distances that are parallel to the line of relative motion. Again, if you had actually tried to learn Relativity, you would know this.

 

-If you see light pulse at BETA distance at 90 degrees to the spaceship's movement, at which angle was it shot outside the spaceship, uh?

[math]\arccos \left( \frac{v}{c} \right)[/math]

Can you see this angle?

Sure, just imagine that the spaceship is open and the light is passing through a series of glass plates. The light will slightly illuminate each plate as it passes though. If the outside observer draws a line through these spot of illumination they will follow this angle.

You applied gamma-factor to the distance, you cannot follow, apply gamma-factor to BETA distances. As seen [math]Y\sin\alpha[/math] does not have gamma-factor.

 

If you can't follow the example just say so, but your inability to understand it speaks more about you than it does the example.

Ct1 and Ct2 and Y belong to inside observer' date='

[/quote']ct1 and ct2 are measured in S which is the frame of the "outside" observer. ct'1 and ct'2 are measured in S' the spaceship frame observer. Or weren't you paying attention

outside observer cannot know ALPHA angle, only BETA angle.

Why? What prevents him from knowing it? Unless you are claiming that the sphere is opaque and that the outside observer cannot see what happens in the spaceship, in which case this whole exercise is pointless.

 

ALPHA times are the same.

And the speed gamma*Y*cos Alpha proves that the distance is not simply Y, it should be gamma*Y.

 

What speed [math]\gamma Y \cos \alpha[/math]?

The only speeds in this example are v which can have any value <c and c, the speed of light in a vacuum.