Disclosure Project by Steven M. Greer: Reliability?

[Physics-Learner]

hi jared,

the type of "reasoning" to which you are referring is common amongst people in all sorts of thought processes, religion being one of them. so can we leave religion out of our discussion ?

what you are referring to is seeking evidence for something that you want to believe.

i certainly did not do that. up until a couple weeks ago, i had dismissed ets, because i thought it had extremely low probablility.

upon listening to all these high level people (who have quality, they are not local yokels from hillbilly country) stating their claims, i could no longer simply dismiss the concept that there could be ets.

if it was any other topic, i believe you, and the average joe, would give it a lot of credence. the fact that you can simply still dismiss it as just an illusion, suggests to me that you are the one portraying biased thought processes.

 

[Physics-Learner]

hi russ,

the time separation between Newton and einstein is pretty small, in terms of number of years. if we go back just a few thousand years to say the ancient greeks, and compare that to einstein - pretty big difference.

that is a few thousand. now try going a million in the future. or 10 million.

it reminds me of the old proverb about a bird landing in a tree, and he asks the other bird there if this tree is alive. the other bird replies, "i don't know, it hasnt moved since i have been here."

in other words, i would not put too much credence in our ability to extrapolate what we may know a million or more years from now, based upon our extremely limited time frame in which we have lived.

as i said, how full is our cup of knowledge. if we fill it one grain at a time, and have a million grains in it, boy are we ever advanced when compared to just the one grain. but if our cup can hold 10 trillion grains before it fills up, we still aint very far along the learning curve.

 

[Physics-Learner]

i am trying to determine what sorts of ways an alien would be able to detect us.

i know our society throws off em waves with our radio and tv transmission.

we are electrical beings. as far as science knows, do our bodies send off any sort of energy. if so, what is it ?

is there any other way that is known, where something on our planet emits some sort of energy ?

 

[russ_watters]

hi russ,

the time separation between Newton and einstein is pretty small, in terms of number of years. if we go back just a few thousand years to say the ancient greeks, and compare that to einstein - pretty big difference.

that is a few thousand. now try going a million in the future. or 10 million.

Since science was invented at the time of Newton (essentially by him and Galileo), you can't extrapolate back further than him.

it reminds me of the old proverb about a bird landing in a tree, and he asks the other bird there if this tree is alive. the other bird replies, "i don't know, it hasnt moved since i have been here."

in other words, i would not put too much credence in our ability to extrapolate what we may know a million or more years from now, based upon our extremely limited time frame in which we have lived.

as i said, how full is our cup of knowledge. if we fill it one grain at a time, and have a million grains in it, boy are we ever advanced when compared to just the one grain. but if our cup can hold 10 trillion grains before it fills up, we still aint very far along the learning curve.

The learning curve is a good analogy that you didn't develop: the cup analogy is an improper view of science that will not serve you well in your quest for knowledge. Scientific knowledge is not gathered in equal-sized grains over time, along a linear path.

The learning curve is a way of saying that knowledge follows a curve with, for example, 90% of knowledge being gained in the first 10% of the time, 99% of knowledge in 11% of the time, etc.

The fact that knowledge advancement is curved and not linear is easy enough to see in the level of accuracy with which we can model/predict natrual phenomena (though that is a little tough beyond the last 100 years, as education wasn't very formalized and the scientific process not very mature). Early in the development of an area of investigation, you quickly hone-in on the true value of a measurement and then you can spend decades digging into that last few percent. For example, here are some of the Michelson Morley experiments done in the first 50 years after it was devised. The accuracy difference between the first and one done in 1927, 46 years later was 99%. The accuracy difference between the first and one done in 1958, 77 years after the first was 99.97%. So after almost twice as much time, the deviation from the expected result only decreased by 0.97%. So that's an even steeper curve than I pointed to above: 99% of the way to the expected result in 40% of the time elapsed between the three data points.
http://en.wikipedia.org/wiki/Michelson–Morley_experiment#Most_famous_.22failed.22_experiment

 

[Physics-Learner]

you are making a statement about how you perceive science to be, such that anything before galileo was not science.

10 million years from now, they may be saying that about us.

btw, the next time i see probably the most brilliant man of all time, i will tell him that he was not being scientific. i will give you a hint - he discovered integral calculus, hydrostatics, statics, the lever, a gazillion mathematical principles, and was able to defeat the roman armies all by his thinking and inventions.

 

[russ_watters]

you are making a statement about how you perceive science to be, such that anything before galileo was not science.

10 million years from now, they may be saying that about us.

No, they won't. It is clear that you don't know what the word "science" means. Science is nothing more or less than a method for investigating the natural world. Before Galileo, there were brief and isolated hints at a method similar to science, but for the most part, people used philosophy and mysticism. The development and acceptance of a functional method for investigating the natural world is the reason why we started actually figuring out how the natural world works. You should read the wikis on the scientific method (starting with the history section), the scientific revolution and the history of science:

http://en.wikipedia.org/wiki/Scientific_method#History
http://en.wikipedia.org/wiki/Scientific_revolution
http://en.wikipedia.org/wiki/History_of_science

A quick quote from the second:

In the history of science, the Scientific Revolution was a period when new ideas in physics, astronomy, biology, human anatomy, chemistry, and other sciences led to a rejection of doctrines that had prevailed starting in Ancient Greece and continuing through the Middle Ages, and laid the foundation of modern science...

The science of the late renaissance was significant in establishing a base for modern science. The scientist J. D. Bernal stated that "the renaissance enabled a scientific revolution which let scholars look at the world in a different light. Religion, superstition, and fear were replaced by reason and knowledge".

btw, the next time i see probably the most brilliant man of all time, i will tell him that he was not being scientific. i will give you a hint - he discovered integral calculus, hydrostatics, statics, the lever, a gazillion mathematical principles, and was able to defeat the roman armies all by his thinking and inventions.

Archemedes is one of those rare examples (as I noted above) of an ancient who was able to actually figure out a lot about how the natural world works. He is a predecessor of modern science who probably could have done a lot more if science had existed then to act as a framework for his investigation. There is a reason guys like him were few and far between: at the time, there existed no logical framework from which to even begin the type of work they did. Whatever method he used, he had to develop from scratch.

Aristotle, on the other hand, was probably an intelligent man, who nevertheless believed that philosophy was the proper way to investigate the natural world. As a result, he came up with a lot of wrong answers to questions he probably should have been able to answer correctly, and his prominence helped to block the advancement of our understanding of the natural world. Among other things, he reasoned that:
-A fly should have 4 legs for stability.
-Objects of different weights should fall at different rates proportional to their weights.

...and he apparently never even bothered to capture a fly and look at it or drop two weights and watch them fall. So ingrained were his misconceptions that it is rumored that a thousand years later, Tycho Brahe used to awe guests at parties by dropping fruit to demonstrate how wrong Aristotle was.

I mean, seriously: how hard is it to drop two pieces of fruit to see that objects of vastly different mass fall at the same rate? It never happened because people simply didn't think that way. Investigation of the natural world truly was a shot in the dark back then and it isn't today. It seems you believe it still is and that is probably why you think "anything is possible".

 

[JaredJames]

the type of "reasoning" to which you are referring is common amongst people in all sorts of thought processes, religion being one of them. so can we leave religion out of our discussion?

I understand this, I was using religion as an example of the type of reasoning. I am not saying you are some religion. It is an example, nothing more.

what you are referring to is seeking evidence for something that you want to believe.

i certainly did not do that. up until a couple weeks ago, i had dismissed ets, because i thought it had extremely low probablility.

You have come to a conclusion based on 'eye witness' reports. Not credible evidence. You have decided that "ets must exist" and are now here looking for evidence to back this up. You have admitted to this. You have made an irrational judgement and are now searching for evidence which backups up said judgement. This is not how science works.

upon listening to all these high level people (who have quality, they are not local yokels from hillbilly country) stating their claims, i could no longer simply dismiss the concept that there could be ets.

We have already shown how 100,000 people, all looking at the same event can be wrong. Why would we accept one person giving a sketchy testimony at best. There is nothing at all to back up their claims.

if it was any other topic, i believe you, and the average joe, would give it a lot of credence. the fact that you can simply still dismiss it as just an illusion, suggests to me that you are the one portraying biased thought processes.

If it was any other topic... I'd still require credible evidence, just like any other rational person. Period.

I personally believe that somewhere out in the universe there is other life. Given the size of the universe I think this is a fairly rational judgement. However, this belief in there being some other form of life (I'm talking anything from single cell to similar to us) is just that. I do not have any reason to accept they can violate the laws of physics anymore than us. Therefore, the probability of them visiting us is extremely low, as you rightly said.
It is the differentiation between these two viewpoints which is key. There is believing there may be "life out there" and then there's believing in "life forms so advanced they can effectively switch on/off the laws of physics on demand to accomplish impossible feats".

 

[JaredJames]

i am trying to determine what sorts of ways an alien would be able to detect us.

i know our society throws off em waves with our radio and tv transmission.

This is the only way to detect us, aside from looking for 'like' planets in the universe as we currently do.

we are electrical beings. as far as science knows, do our bodies send off any sort of energy. if so, what is it ?

is there any other way that is known, where something on our planet emits some sort of energy ?

And now we are deeply in the realms of crack-pottery and psuedo-science.

Nuclear bombs, power stations, microwave ovens, lights, engines and so on. There are a lot of things emitting energy, but not substantially. The Earths gravity is one of its biggest influences on surrounding space, but even that is nothing in comparison to other sources in the solar system.
Again, look at how we are currently looking for planets.

 

[Physics-Learner]

russ,

i agree with your last post. i am very familiar with the scientific method. if i recall, it was actually started by the empiricists, who actually "battled" aristotle, but lost out. and then we went thru the dark ages, and it got even worse.

that is where the we get the term "empirical method".

contrary to his usual arrogance, Newton is credited with saying something to the effect that "if i have made a lot of contributions, it is because i was able to stand on someone's shoulders".

he was referring to copernicus, kepler, and galileo.

aristotle had no shoulders to stand on.

i can't think of any more astonishing scientific find than when we discovered at least some of what he had written down on "paper". if i recall, it had been written over by the monks, but not erased, such that we still had access to at least that tablet.

he was so far ahead of his time, that people (especially the romans) considered him to be a magician. instead of killing him, they were actually trying to capture him for themselves to take advantage of his knowledge.

 

[Physics-Learner]

hi jared,

earth's gravity would be of no help, since that would only denote that there was a planet there. i was looking for ways of determining "intelligent" life. and then trying to determine what an alien could do in order to find us.

radio has been around for 100 years or so ?

fyi, i don't take faster than light easily, either. and we have no physics whatsoever to explain what happens at ftl.

it would not surprise me though, if we as electrical beings emanate some sort of energy that is detectable by an advanced civilization. but let's assume that we dont.

that only gives aliens the last 100 years with which they could have discovered life on our planet.

if my relativity is correct, both us and the aliens would measure that it took "x" years to get from us to them, if they are "x" light years away. they pack up, and leave that day, traveling at the speed of light. they measure that they get here instantly, but we still measure them as taking another "x" years to get here.

which means that we measure it as taking "2x" years for the entire process. if our first signal left 100 years ago, then the alien could at most be 50 light years away, which is very close by the terms that we usually use when we talk about neighboring solar systems, etc.

 

[Physics-Learner]

hi jared,

i have not come to a conclusion "that aliens must exist". i do suspect that they exist, but i am at this site regarding "are they here". i am now open-minded about it, whereas before i had not given it enough probability that i ever looked into it. the disclosure project interested me enough to give it some consideration.

i am being very scientific, as i only want the truth.

i have stated over and over again that there is a huge difference between one event being witnessed by 100,000 somewhat primitive people, versus several hundred DIFFERENT events being witnessed by top level military people.

to pass that off as them all seeing illusions gets almost to the point of being ridiculous. as i said to flex, the probability is not 0, but pretty darn close.

i think there is a much better chance that they are all lying, and working on some sort of agenda, than that everything that they have claimed to have seen WERE ALL ILLUSIONS.

 

[FlexGunship]

you are making a statement about how you perceive science to be, such that anything before galileo was not science.

10 million years from now, they may be saying that about us.

You are fundamentally wrong in this assertion.

At one time we did not have Boyle's law, but now we do. Nothing will "undo" Boyle's law except a fundamental change to the physical constants of the universe.

At one time we did not have Maxwell's equations, but now we do. Nothing will "undo" Maxwell's equations except a fundamental change to the physical constants of the universe.

Take some time and actually consider that. Even if the equations are made more accurate, or modified to better reflect reality, that doesn't mean that they are fundamentally wrong right now. They do a remarkable well describing reality even if the're slightly wrong.

Science is cumulative.

 

[FlexGunship]

i am being very scientific, as i only want the truth.

You are NOT being scientific. Simply wanting the truth does not make your endeavor scientific in the slightest. In fact, you are behaving in a profoundly unscientific way!

You are allowing wishful thinking to cloud your judgement. You are accepting some data as preferential to other data. You are disregarding negative results.

All signs of a ruined experiment.

i have stated over and over again that there is a huge difference between one event being witnessed by 100,000 somewhat primitive people, versus several hundred DIFFERENT events being witnessed by top level military people.

to pass that off as them all seeing illusions gets almost to the point of being ridiculous. as i said to flex, the probability is not 0, but pretty darn close.

Don't you get it?! A crowd of 100,000 people (including university professors) claimed to see the sun fall from the sky. Integrate this into your thought process.

Learned, intelligent, smart, trained, highly academic people in a HUGE crowd of other observers from all walks of life can all succumb to illusions. They're not even primitive as you claim. This was Portugal in 1912.

It's getting very frustrating. People are giving you articles to read. Information to absorb but you claim stupidity and ignorance as a defense. How can you not see this?

You've clearly made up your mind already.

 

[Physics-Learner]

i give up on you guys. you might want to look into a mirror.

good-bye.

 

[JaredJames]

Hold it, hit the brakes right now. You've gone way off the radar this time!

earth's gravity would be of no help, since that would only denote that there was a planet there. i was looking for ways of determining "intelligent" life. and then trying to determine what an alien could do in order to find us.

Aside from radio transmissions, there is no way to tell if intelligent life exists on a planet without visiting.

radio has been around for 100 years or so ?

Right, so it only covers a maximum of 100 light years. Not even remotely close enough to cover enough solar systems. We would be very lucky if something has picked it up by now.

fyi, i don't take faster than light easily, either. and we have no physics whatsoever to explain what happens at ftl.

You are taking it easily, you are saying "aliens have visited and as such they must have traveled faster than light or used an alternate dimension". We have physics which show we can't get to the speed of light, what happens at it is irrelevant.

it would not surprise me though, if we as electrical beings emanate some sort of energy that is detectable by an advanced civilization. but let's assume that we dont.

Let's just be blunt here, we do not emanate some magical 'energy'. Period. This is akin to people claiming we have auras'. Complete BS. To say "lets assume that we don't" is saying "we do, but for the purpose of now, we'll pretend we don't". We do not. There is no evidence for it and as such is a personal theory and purely speculative on your part.

that only gives aliens the last 100 years with which they could have discovered life on our planet.

Correct.

if my relativity is correct, both us and the aliens would measure that it took "x" years to get from us to them, if they are "x" light years away. they pack up, and leave that day, traveling at the speed of light. they measure that they get here instantly, but we still measure them as taking another "x" years to get here.

which means that we measure it as taking "2x" years for the entire process. if our first signal left 100 years ago, then the alien could at most be 50 light years away, which is very close by the terms that we usually use when we talk about neighboring solar systems, etc.

I give up on this, we're getting nowhere.

You're refusing to accept even basic principles and proofs given by people here.

 

[JaredJames]

i have stated over and over again that there is a huge difference between one event being witnessed by 100,000 somewhat primitive people, versus several hundred DIFFERENT events being witnessed by top level military people.

Primitive? Do you realize who was there? If anything I'd give them more credit than some jumped up army guy. What makes an army official less prone to illusion / hoax / mind tricks than anyone else?

to pass that off as them all seeing illusions gets almost to the point of being ridiculous. as i said to flex, the probability is not 0, but pretty darn close.

Are you truly entertaining the fact that the sun collided with the earth? It is impossible. There's no argument. Which means all 100,000 people where wrong.

i think there is a much better chance that they are all lying, and working on some sort of agenda, than that everything that they have claimed to have seen WERE ALL ILLUSIONS.

Correct, their agenda was to want to believe in what this guy was saying (the followers anyhow). You then include group thinking into it and you end up with a situation where 100,000 people including both believers and non-believers thinking they saw something.

 

[FlexGunship]

i give up on you guys.

It's unfortunate that you've given up. This site is an excellent resource for intelligent discussion. You don't have to agree with the people you talk to, but you must provide more substantial arguments or you will continue to get walked all over.

If you don't have more substantial arguments, then you need to reevaluate your position. This is a clear indication that you might be wrong.

Not all viewpoints are equally right or respectable; regardless of what they told you were a kindergärtner.

 

[JaredJames]

I think he's thinking along the lines of Star Trek and its sensors that can detect 'bio signs' over a few light years. Movie physics at its best!

 

[JaredJames]

Well put flex.

He came looking for answers, he didn't find what he wanted and so left (presumably to go elsewhere to find the 'right' answers).

I didn't want to joke about it either, I find it rather distressing that people are so closed minded like this. But if I don't use humour, I end up venting some anger at their ignorance. That doesn't end well.

 

[Physics-Learner]

Since science was invented at the time of Newton (essentially by him and Galileo), you can't extrapolate back further than him. The learning curve is a good analogy that you didn't develop: the cup analogy is an improper view of science that will not serve you well in your quest for knowledge. Scientific knowledge is not gathered in equal-sized grains over time, along a linear path.

The learning curve is a way of saying that knowledge follows a curve with, for example, 90% of knowledge being gained in the first 10% of the time, 99% of knowledge in 11% of the time, etc.

The fact that knowledge advancement is curved and not linear is easy enough to see in the level of accuracy with which we can model/predict natrual phenomena (though that is a little tough beyond the last 100 years, as education wasn't very formalized and the scientific process not very mature). Early in the development of an area of investigation, you quickly hone-in on the true value of a measurement and then you can spend decades digging into that last few percent. For example, here are some of the Michelson Morley experiments done in the first 50 years after it was devised. The accuracy difference between the first and one done in 1927, 46 years later was 99%. The accuracy difference between the first and one done in 1958, 77 years after the first was 99.97%. So after almost twice as much time, the deviation from the expected result only decreased by 0.97%. So that's an even steeper curve than I pointed to above: 99% of the way to the expected result in 40% of the time elapsed between the three data points.
http://en.wikipedia.org/wiki/Michelson–Morley_experiment#Most_famous_.22failed.22_experiment

hi russ,

here is a bit of a devil's advocate for your consideration. we have no idea where we are on the knowledge scale. obviously, you think we are further ahead than i do.

your example is about a specific "discovery". and i can buy that. but that doesn't negate my analogy of the cup at all. what it is equivalent to stating is that once we toss one grain of sand into the cup, most often another 100 grains of sand fall into the cup soon after.

but it still gives no limit to the number of grains of sand that the cup can hold. the fact that we are pretty good at a specific topic, once we are aware of said topic, lends no credence to how fast we are at learning about some other topic.

let's consider evolution. there are 2 accepted forms of it, that do not contradict one another. most people are well aware of darwinian evolution. if i recall, one of the first realizations involved birds or bugs on trees. as pollution started making the bark darker, all of a sudden the darker animals had better camouflage, and started thriving. basically the survival of the fittest. this is what is called short-scale evolution.

then there is long-scale evolution, such as the asteroids killing off the dinosaurs and many other forms of life.

the history of learning is so short when compared to evolutionary study, that i would simply caution all of us as to placing too much confidence in "what we know to be true".

i am old enough that i have been humbled enough to appreciate this. i still recall when schooling was my only source of learning. i still recall when everything i learned at school was all correct.

i most certainly still am a big advocate of science. but what i now appreciate is that science has and will continue to evolve. we had at least a mini-big-bang when copernicus, kepler and galileo re-ignited the scientific method, and got us back on the right track.

but we may have many more mini-big-bangs as well a big-bang sometime in the future millions of years, that will once again rock science as we had come to know it.

scientists do not like to admit this, because it rocks their comfort level.

unfortunately, i find many similarities between both followers of science and followers of religion - both respond very defensively if you rock their respective boats.

for me, it is simply a search for the truth - the source is not important, only the resultant truth, whatever it may be.

 

[jreelawg]

I believe it is gravity and acceleration, not velocity, which cause time dilation.

Now this isn't totally serious, and just a hypothetical, but if anti-gravity were possible, and UFO's were able to achieve it fully, then you would not experience gravity or G-forces.

Under such circumstances, would time really slow down relative to earth, or would it speed up?

If a spaceship which could block gravity, and inertia, would experience time dilation explain.

 

[JaredJames]

jreelawg, are you trying to say that a ship traveling constantly at 99% light speed would not experience time dilation?

The SR-71 cruising at high altitude/speed experiences it, just not to a great extent. I believe they did an experiment to show it with atomic clocks.

This of course is along with the ISS, GPS satellites (or just satellites) etc. All traveling at virtually constant velocity (unless we're bringing centripetal acceleration into this).

 

[jreelawg]

jreelawg, are you trying to say that a ship traveling constantly at 99% light speed would not experience time dilation?

The SR-71 cruising at high altitude/speed experiences it, just not to a great extent. I believe they did an experiment to show it with atomic clocks.

This of course is along with the ISS, GPS satellites (or just satellites) etc.

It is pretty clear what I'm asking. If you think time would slow down in a theoretical anti-gravity space ship, then explain how.

 

[Physics-Learner]

it isn't clear to me, either. you did state that one does not experience time dilation because of velocity. time dilation is a result of special relativity, which is only about constant velocity.

 

[JaredJames]

I don't see what anti-gravity has to do with time dilation? Strictly speaking, enough anti-gravity should have the opposite effect of massive gravity. Whether you have no gravity or 'earth' gravity, whilst traveling near the speed of light, there is time dilation.

Gravity induced time dilation is not the same as velocity induced time dilation. You can either have them both together, or on their own. You do not need velocity whilst under immense gravity to cause time dilation, and netheir do you need gravity whilst traveling at high velocity.

 

[jreelawg]

it isn't clear to me, either. you did state that one does not experience time dilation because of velocity. time dilation is a result of special relativity, which is only about constant velocity.

Velocity is relative. As far as space time is concerned, a non accelerating object is not moving. It is a common misunderstanding that velocity causes time dilation. Time dilation is caused by acceleration, as well as gravity. Acceleration is a different thing than velocity.

There are stars out there which are moving faster than C relative to earth, this doesn't violate relativity.

 

[JaredJames]

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

Focus on: Relative velocity time dilation (or any part really, it's all good).

 

[Physics-Learner]

einstein was basically interested in light, regarding special relativity. and gravity regarding general relativity.

but put more exactly, special relativity is based upon non-accelerated frames of motion, whereas general relativity is based on accelerated frames of motion.

i am not familiar with gravity-based time dilation, but time dilation first came into being based upon light, the special theory of relativity, and of course constant velocity.

 

[jreelawg]

Sorry for the confusion. I admit, I am very confused. In the case of stars which are moving faster than C relative to us, does anyone know how time dilation factors into the equation? I believe it was an explanation from a PF mentor about how this does not violate relativity, which got me confused, as it is a hard one to explain, and intuitively makes no sense at all. I guess the important thing is that the equations work.

Anyways, who's clock, ours, or theirs, moves faster? According to us, they are moving faster than C, according to them we are. So according to us, time for them has stopped completely? According to them, time for us has stopped completely?

The way it was explained to me, is that objects can travel relative to others at speeds greater than C, but can never accelerate to C relative to our own reference frame. I understand why inertia prevents accelerating to C instantly like light does, but fail to understand why some far out star can move faster than C relative to us, and we can't achieve C relative to a prior self reference frame, even under mild acceleration over the coarse of many many years.

 

[JaredJames]

Think of it like this:

If you have two space ships heading towards each other at 0.6c, it is the same as having one spaceship traveling at 1.2c towards a stationary object. But in the case of two space ships, their relative speed is 1.2c, but neither one actually travels faster than c.

 

[jreelawg]

Think of it like this:

If you have two space ships heading towards each other at 0.6c, it is the same as having one spaceship traveling at 1.2c towards a stationary object. But in the case of two space ships, their relative speed is 1.2c, but neither one actually travels faster than c.

So your saying that the maximum relative velocity between two bodies is just under 2C?

 

[FlexGunship]

jreelawg, are you trying to say that a ship traveling constantly at 99% light speed would not experience time dilation?

The SR-71 cruising at high altitude/speed experiences it, just not to a great extent. I believe they did an experiment to show it with atomic clocks.

This of course is along with the ISS, GPS satellites (or just satellites) etc. All traveling at virtually constant velocity (unless we're bringing centripetal acceleration into this).

Well, jreelawg has a point. Time dilation occurs both at different relative velocities and at different relative accelerations (i.e. gravitational acceleration). Both effects cause differences in "clocks." (http://en.wikipedia.org/wiki/Time_dilation)

So, his question was," if you remove the acceleration component does time dilation still occur?"

The answer is, "yes." Regardless of how someone gets to the speed, if their movement relative to another observer is non-zero, time dilation will occur. The "photon-clock" is the best example I know of this.

Imagine a photon bouncing between two idealized parallel mirrors. Based on the rate of impact, you can tell the passage of time. Since the speed of light is a constant (regardless of motion) if you put the photon-clock on a train, the net distance between the mirrors becomes a hypotenuse (based on the trains movement forward, and the photons movement up/down). Since the photon must still hit the mirrors at the same rate (can's slow down c) the time inside the train appears constant no matter what speed (as the observer maintains a zero relative velocity with the clock). However, an outside observer sees the photon traveling a diagonal distance farther, and therefore a longer time between the hits on the clock.

The end result, time appears to pass more slowly on the train to the outside observer.

(Credit to Brian Greene for the thought experiment.)

 

[FlexGunship]

Think of it like this:

If you have two space ships heading towards each other at 0.6c, it is the same as having one spaceship traveling at 1.2c towards a stationary object. But in the case of two space ships, their relative speed is 1.2c, but neither one actually travels faster than c.

Um... mistaken?

The relative speed to either observer is no more than 1c - iota.

v = (w-u)/(1 - wu/c^2)

Solving for v you get 0.88c for their relative velocity.

 

[JaredJames]

Well, jreelawg has a point. Time dilation occurs both at different relative velocities and at different relative accelerations (i.e. gravitational acceleration). Both effects cause differences in "clocks." (http://en.wikipedia.org/wiki/Time_dilation)

I gave that link above, and I have never argued against acceleration due to gravity. However, jreelawg was claiming that relative velocity time dilation didn't exist. So yes, if you were under a high g field and applied ag you would cancel out the time dilation, but he was claiming a spaceship traveling through space wouldn't feel it because of ag, confusing gravitational time dilation with velocity time dilation.

 

[FlexGunship]

Sorry for the confusion. I admit, I am very confused. In the case of stars which are moving faster than C relative to us, does anyone know how time dilation factors into the equation?

First, you must adjust your thinking. They are not moving through space faster than c. This is a fact. Add it to your knowledge. They are moving less than c through space.

However, space is expanding. The farther away from the Earth you go, the faster it expands. Where the expansion rate exceeds c, there is a "visible horizon." The space is expanding faster than light can travel through it.

The stars are certainly still traveling much slower than c.