Galileo & Einstein - second thoughts

I still don't agree with you, but let me get back to this tomorrow. You seemed to have missed out the thought I had about those huge systems who are all moving away from each other and which COULD be used in SOME SENSE as a *standard* frame of reference.

 

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These are busy weeks, too busy actually, I'll answer shortly, Sorry for that, I will take the time to answer your (long) replies better

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""Draw a circle on a piece of paper. Imagine your pen tip is the Earth and the centre of the circle is the sun. When you start drawing, let's say your pen moves to the right. Then, when you have drawn half the circle your pen will be moving to the left.""

for me the earth always moves clockwise (or is it anti-clockwise?), I guess you understood what I meant

"""all you have to do is to come up with ANY test which can tell me unequivocally who is moving and who isn't. If such a test was possible, surely you'd be able to explain it to me?"""

I'll explain you my friend

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This is the story of the arrogant observer who thought he knew it all. His eyes were as a gun to him

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This is my new thought on this:

object A has coördinates x1,y1 and z1
object b has coördinates x2, y2 and z2

Everything is dark. Only object A and B can be seen. They are both approaching to each other. You are observing this.

Relativity says that you cannot know which one of the two is moving because you have nothing to REFER to. But that's not where relativity stops. If it would stop there, it would be fine for me. It then goes on to conclude that the motion shoud depend on which FOR you take. This is someting I cannot agree with.

Well let me tell you, it is entirely because the observer is limited in doing science. IMAGINE that we'd know that the coördinates of A remain x1,y1 and z1 and that object B's coördinates are changing from x2, y2 and z2 to x1/2, y1/2 and z1/2 to etc. etc.

How can we test this? We cannot. Fact is, in this gedankenexperiment, the coördinates are there and somehow we know that A's coördinates remain unchanged, conclusion: B is moving and A isn't.

Imagine we are all gifted and we'd be able to see the structure of the space surrounding us. We'd see it like they see it in mathematics. A sea of points. Every object has its coördinates. Problem is, we are not that gifted. Space is an ABSOLUTE FOR but unfortenately, we cannot use it. This is not proof in favour of relativity. This is a conclusion that we draw.

""I am telling you that no such test is possible. And Einstein agrees with me.""

Hey I agree also. But you can't use this in favour of relativity. You should check the path of logic you are following here. The physics community has been mistaken in doing this.

""IHave they observed that the clocks on earth went slower for the pilots?

Yes. """

I would like to have some links that give me a rapport of this experiment and where i can read how that hapenned.
Simply saying yes does not do the job.

"""That's not quite true. It is most easily applied in the case of no acceleration, but you can solve the equations numerically where there is acceleration. Things just become a lot more complicated."""

--> thed said this

"""That is wrong. We can easily test it. All we need to do is to do ANY experiment in both a "stationary" reference frame and another one moving at constant velocity relative to it (like the car and the bystander on the road), and get different results WHICH ALLOW US TO TELL WHO IS "REALLY" MOVING."""

No you can't test it. The principle is not a physical principle and therefore it cannot be tested. Motion remains an objective thing which happens in the space-dimension (with time as an additive variable). Motion cannot change because an observer is at an other coördinate in space. The penny that was dropped on the train falls straight with the observer on the train because the observer is moving with the penny and hence his observation is an illusion caused by his own motion. There's nothing special about it. The penny's motion seen from the point of view of the Space dimension is always the same. No test can be performed to use it but that is no argument. The scientist as an observer should understand this. Do you understand this?

"""So, we're back to the original question - can you come up with one?"""

I don't have to. You are missing the point.

Gotta run now. Hope not too many typos

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Hrmmmmmm

Hi c'est moi

"Everything is dark. Only object A and B can be seen. They are both approaching to each other. You are observing this.
Relativity says that you cannot know which one of the two is moving because you have nothing to REFER to."

Wrong. For the outside observer, both are moving. From the point of view of object A, B is moving. From the point of view of object B, A is moving.

"But that's not where relativity stops. If it would stop there, it would be fine for me. It then goes on to conclude that the motion shoud depend on which FOR you take. This is someting I cannot agree with. "

Well, then you don't agree with anything you see in your every day life.

Have you ever sat in a car that was cruising along the highway ? From that perspective, you see the trees alongside the road moving, and the car does not move for you. The reasoning you make is the following: it is because you KNOW that trees don't move by themself that you can deduce that the car is the object moving. Hence the prefered frame of reference is the car.

The problem is that this is only half the story. If I would put the trees on small wheels and move them backwards, then you would have the same impression, even though it is not the car moving in that scenario.

I'm sure you ever experienced the following situation: you are sitting in a train that is standing still in a railway station, and suddenly the train standing still next to you starts to move. The first thing that pops into you mind is "hey, we've started moving again" until you realize you don't feel the normal acceleration you experience when trains depart (this gives this strange feeling in your stomache

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).

The point is: motion is very dependent of the frame of reference.

Bye!

Crisp

 

c'est moi

i appolagize if this issue has already been resolved, but i am tired of spending all day in this forum, so here it goes. as to the baseball example, the FOR should be yourself, but imagine that you become the point inbetween the earth and the ball. the ball magicly leaves the earth, and you see the ball traveling quickly, and the earth traveling slowly(because it is much more massive than the ball) and you remain in the center of gravity between the two

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James R,

There is such a thing as an absolute frame of reference.

The relative velocity of an object is equal to the difference between that objects absolute velocity, and the absolute velocity of the object you are comparing it to.

In other words, the relative frame of reference of object A compared to object B, is derived from the absolute physical values of object A and B. If an absolute frame of reference didn't exist, neither would any relative frames of reference.

Just because there isn't yet a way to measure the absolute frame of reference of an object, doesn't mean that an absolute frame of reference doesn't exist.

Tom

 

James R.

The unrelativistic properties of light in any frame of reference is proof that there is an absolute frame of reference.

Tom

 

"""I'll use the classical train example here. If you drop a penny inside the train, an observer standing in the train will say it fell straight down, and someone observing that experiment next to the railroad will say it fell in a curved way. Since we're both talking about the very same penny dropping - and very important - and that we both assume that the laws of physics are the same for everyone, then there must be some way to relate the results."""

we must not forget about illusionary visions

"""First of all, if you assume the laws of physics to be different for two observers, then you can stop reading here. If everybody has his own sets of rules and laws, then there is no possible way that we can ever agree on the results of an experiment (you will firmly believe your measurement because you saw it happen with your own eyes, I will firmly believe what I saw).""""

I never questioned this. Indeed, all laws are the same for anyone, when I see motion and you don't, then one of us is wrong. Simple.

"""This is exactly the (Galilei) principle of relativity, and I quote it here for reference:

"""The second point is the definition of an inertial system, and well, a definition is a definition, there is no right or wrong there (perhaps a "useful" or "worthless", but you can never disagree on a formal definition)."""

I read the quote of Galileo about the boat and I still don't agree with it.

"""Disagreeing with the Galilei principle of relativity is disagreeing with the fundamental building blocks of science: if you cannot use mathematics to describe nature (first point) or if you don't believe there are other FORs (point two), or if you refuse to assume that the laws of physics are the same for everyone, well then there is no point in continuing science."""

1. Maths are an abstractation of reality yet usefull, we need to be carefull with the interpretation of numbers. With maths alone, anything can be prooven. We also need to understand that maths is only an translation of what we think is happening.

2. Points of view or FOR's are a fact. But don't we all agree in life that certain people are wrong in their point of view? A guy who's nuts and who's seeing all kinds of non-existing creatures on the street, is surely telling his point of view of his reality. Who are we to laugh with him? Can we be 100% sure that what he sees is not true? Yet, normal people will tell him that we he sees is wrong and what they see is reality.

I strongly believe that switching between FOR's is more about illusionary effects than reality. The train-scenario is an illusionary effect and is basically an example where information is the key. If we would be supersensitive beings and feel every detail of the topography below us in a train, we'd perfectly be able to tell if out train is really moving or if it is an illusionary effect. If we'd be unlimitely sensite we'be able to feel space and use that as absolute FOR. Unfortenately we can't.

"""That assumes the existance of an absolute frame of reference (or aether as James R called it). When you say that something is moving, you always have to specify what it is moving relative to.""""

I would like to hear a defenition of "motion" which is the key-word of this debate in light of the rel. principle.

I strongly believe that motion is like mass. It's independent. Likewise, the motion of light is independent and absolute which proves motion can be this.

"""You can repeat this argument a couple of times, you'll always end up with the same conclusion: I can see all the other FORs moving, but since I am also moving, what am I moving relative to ?"""

to space

Motion is defined as moving through space.

"""However, from our point of view, the earth is stationary: we walk on it, and for some magical reason (no magic involved ofcourse) it doesn't move away from our feet."""

that's because it's speed is rather constant

"""That's because in our daily lives we talk about the FOR of the earth, and the earth is stationary in that FOR."""

that's our big illusion
our view is so to speak "defect", because we ourselves are always moving with it

the only objective observer is one who is not in motion himself

"""Well, I can see this one coming from a mile away: you are going to question the mathematical formulas used to transform from one FOR to another. Unfortunately, these transformation rules are deduced immediatelly from the principle of relativity."""

they were originally used within an absolute frame of reference

"""Well, the Lorentz transformations are immediatelly deduced from these simple four points."""

you are going in the wrong direction here if I know my history well enough

first came along the equations, then Einstein

'The principle of relativity IMPLIES itself, that we CANNOT know or test in ANY WAY if it is CORRECT in it's OWN assumption that WE cannot know WHO IS REALLY MOVING.'

"""First of all, the principles that construct a theory can never falsify the theory itself. External theories are required to do that, which is why no falsification is possible from the point of SR."""

this is very much wrong
imagine I invent the evolution theory right now
we find all the fossils in logical order
then comes a day where we find complex human beings in layers where they shouldn't be as predicted by my theory
and more days come like that
well, this is falsification of the principle of evolution from within the theory itself

"""You say that we cannot tell who is really moving, yes that is true and is one of the basic reasons why most scientists don't believe in an absolute frame of reference, or aether. I think I've addressed the absolute/relative FOR issue in enough detail above ."""

I think you haven't understood or interpretted correctly my quote which I have left between '... ' .

"""The principle of relativity is a postulate, and I hope that you'll agree that it is not as unreasonable as you might have thought at first."""

it is

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"""Have you ever sat in a car that was cruising along the highway ? From that perspective, you see the trees alongside the road moving"""

no, i pass by them
I'm not a cow so I understand this

""and the car does not move for you. The reasoning you make is the following: it is because you KNOW that trees don't move by themself that you can deduce that the car is the object moving. Hence the prefered frame of reference is the car."""

wrong. Hence, information is the tool of the observer.

"""The problem is that this is only half the story. If I would put the trees on small wheels and move them backwards, then you would have the same impression, even though it is not the car moving in that scenario."""

right --> impression, not reality

"""The point is: motion is very dependent of the frame of reference. """

the point is that the observer is quite pathetic and not so much of a good observer

 

"""Do you agree that people have different points of view? """

yes, but some of them seem to be wrong as well

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"""You've missed the crucial point: where am I in this picture?."""

I thought you'd understand that the observer is watching this happening and is not on one of the objects.

so again, Relativity says that you cannot know which one of the two is moving because you have nothing to REFER to.

"""Change your point of view and the world looks different."""

take some LSD or XTC it changes even more beautifully

"""You're assuming a particular co-ordinate system here and you don't even realise it."""

space itself is quite a mystery ... what is it really? it's about dimensions and we've got some mathematical definitions for it but it's actually a curious thing
space for me is absolute
anything has unseen coördinates in space which are independend of anything

"""But in fact, there are MANY different co-ordinate systems we could choose."""

we don't choose

"""Wrong. That's what I keep telling you, but you don't understand. Once again: THERE IS NO ABSOLUTE FOR. If there was one, you'd be able to do an experiment to show whether an object is "really" moving."""

That's what I call wrong logic. I told, there is probably no such experiment because we are limited. Limitation don't mean that a principle is prooved.

"""And you yourself admit that no such experiment is possible. Therefore, logic compels you to accept my statement."""

look up "logic" in a dictionarry

"""I don't have time to search the web right now to find the relevant paper. I'm sure you can find it as well as I could, if you're really interested."""

I'm not really interested. If you say something you have to say why.

"""No. In that observer's FOR, the penny really drops straight down. That's no illusion. It's real. He can bend down and pick it up."""

yes, and whilst he is bending down, he is still moving with it
it's still an illusionary effect of his own motion

 

C'est Moi and James R,

If light always follows an absolute frame of reference, couldn't the absolute speed and direction of an object be measured using lasers??

Example: The absolute motion of an object would be the difference between the direction and speed of a beam of light(which is absolute) and the relative frame of reference of the object.

I believe a device could be built, using three lasers and a gyroscope, which would be able to measure the absolute motion of an object.

Tom

 

James R, I looked it up and as I initially thought your are wrong.

http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/airtim.html#c3

Prosoothus, this idea seems interesting

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1) The measuring device would have to take into account all the changes in material and gravity and all between point A and point B, to make sure speed calculations are correct.

2) Point A and point B are still in relative motion.

 

"""You're very good at asserting that I am wrong, but you seem incapable of providing any evidence of that other than your gut feeling."""

the evidence is all about the limitations of the observer
limitations cannot become principles

"""Much as I might respect your guts, I find that I have to side with Einstein, Galileo, Newton, and practically every practising physicist on this question."""

everyone is free to think and to believe what he wants but it's interesting to discuss these thoughts and believes

"""I asked: Do you agree that people have different points of view?
You said: yes, but some of them seem to be wrong as well

Then you'll be able to provide a test by which I can tell who is right and who is wrong in any situation, won't you? So, I drop a penny in a train and see it fall to the floor. You say that's wrong. What test can I do inside the train to show that the penny doesn't really drop straight to the floor?"""

you, the penny and the floor are moving together as one system
the penny doesn't REALLY follow a straight path nor a curved path
I have no idea what the REAL motion is of the penny because I as an observer am moving myself
only a complete stationary observer could tell this
I don't think that this is possible so again, we are limited in knowing these things
things we see are affected by our own motion

"""From where? From the planet Mars? From inside a spaceship flying past at half the speed of light? From sitting on object A? Where?"""

There is nothing except Space, one observer and two objects. The observer can only see those two objects. The observer has a space-suit on and is "somewhere" in the dark space doing nothing.

"""Oh? Perhaps you'd like to support that statement with something other than gut feeling, because I've given you lots of reasons why that is not the case, yet so far you've given me no reason why it is the case."""

space is about dimensions
dimensions are like a sea of endless points
each point represents a coördinate which is totally independent of objects

"""You replied, rather cryptically: we don't choose

What????!!"""

Space is entirely objective.

"""I looked [the clock experiment] up and as I initially thought your are wrong.

Wrong about what? Wrong in what way? I don't think so."""

Yes you are wrong. Your statement in that previous post is wrong or the information on that website is incomplete which I don't think. It was a one-way experiment like all the others. If not so, then explain me why this website and all the others give a one-way information about the collected data.

And James R, what about the absolute motion of Light? It seems that there are absolute things ... what would the theory of relativity be without this absolute light? It wouldn't be there. Motion can be absolute just like light shows us. I will be repeating myself if I go further.

 

"""2) Point A and point B are still in relative motion."""

imagine we would have discovered the aether
we calculate all motion RELATIVE to the absolute aether
so, what's your point?
motion IS relative to space

 

James R,

That's what you think.

I don't have it completely worked out, but this is a general outline:

The moving object would have two devices.

The first device would be a gyroscope, which would measure any changes in speed and direction of the moving object.

The second device would use three lasers, one for each dimension, to measure the absolute velocity of the object. Because light always travels in the absolute frame of reference, the absolute motion of the object can be measured in two ways:

a) By measuring the curvature of the beams of laser light. If the object is at absolute rest, there would be no curvature of the laser beams. The greater the absolute speed of the object, the greater the curvature of the laser beams.

b) By measuring the time it takes the laser beams to hit their targets. If it takes longer for the beam to hit the target, that would mean that the object is traveling in the same direction as the laser beam. Using the time difference from all three laser beams, the three dimensional absolute velocity of the object can be induced.

Tom