Where are the questions? I see you are avoiding my post #98, while making vague claims about my non-response?
By the way you did not answer which definition...Webster's, oxford, wiki, xyz thesaurus..... defines that "truth" is falsifiable?
Galaxies going faster than light ?
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Where are the questions? I see you are avoiding my post #98, while making vague claims about my non-response?
By the way you did not answer which definition...Webster's, oxford, wiki, xyz thesaurus..... defines that "truth" is falsifiable?
First of all there is expansion of space between the MW and the Andromeda galaxy, just as there is expansion of space everywhere. You also mention that there is 'contraction' which is not correct. The Andromeda galaxy and the MW are moving towards each other due to gravity, space is not contracting.
The space between the Andromeda galaxy and the MW is expanding but the movement of the galaxies through space due to the graviational attraction is greater than the expansion of space.
The idea that there could be 2 galaxies that have no relative distance change due to the expansion of space being exactly offset by a gravitational attraction sound perfectly feasible. This of course would be a temporary situation because any interation with another massive object will cause this equilibrium to fall apart.
I think you wrote this question wrong. I think you meant that FTL would not be a problem with expansion of space? If so that is correct since with the expansion of space the galaxies are NOT moving THROUGH space at a FTL speed. The gravitational attraction between 2 objects will never result in the objects exceeding the speed of light. Again, space is not contracting with gravitational attraction.
The expansion of space is about 67 (km/s)/Mpc, so if the movement of 2 bodies due to gravity exceeds that then they will 'neutralize' the expansion of space and move toward each other.
Correct. The equation is only applicable to objects a very great distances. For distances where gravity can overcome the expansion of space (such as the MW and the Andromeda galaxy) the equation will not give the correct answer.
No that is not correct, the expansion is independent of the masses. The mass is important for the change in distance between the 2 masses when they are close enough that the gravity becomes significant relative to the constant expansion of space (I am neglecting the effect of dark energy from the discussion for clarity).
You are correct that is not the theory - the expansion of space is independent of the masses.
Could you now supply the answers to the questions put to you?
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When did I say the truth was falsifiable? If you recall Post 69:
http://sciforums.com/threads/galaxies-going-faster-than-light.157819/page-4#post-3403799
I provided a dictionary definition of truth as per Google's automatic search results.
This is consistent with the Oxford Dictionary:
https://en.oxforddictionaries.com/definition/us/truth
Read your post #69 and #80......see for yourself what you said.
If you accept a theory as true today, then since that theory is falsiable, the truth also becomes falsifiable. This is what you are trying to push. I disagree. Truth is not falsifiable, our beliefs are.
As I told you, my belief based on certain observations of your signature, was that you were a female. But truth is that you are not a female. My belief is mutable not the truth.
I am not going to argue any further with you on this. If you still feel that truth is mutable and unstable and fasifiable, so be it.
Falsifiable and Unchanging are not the same... thus, what we know as the truth can change as our collective knowledge grows.
Plus, your example is erroneous - how do you know if I am male or female? Is it because you have met me? Or you "found" me? Perhaps I simply said so?
How do you know any of that to be true? For all you know, I could be nothing more than an advanced AI in a computer somewhere. So, how is it that "the truth is that I am not female", when you cannot prove this?
Here are the questions that I do not believe you answered.
How can one discuss anything to someone who thinks the following is discussion...
And note, that was to James R and not paddo.
I will stick him back on ignore and let the thread continue.
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Another explanation for a galaxy traveling faster than the speed of light, is the estimate for distance is too large. For example, say we assume a distance of one light year and light appears to travel that distance in six months. One can either say that light is traveling twice as fast as the speed of light, so we can retain our estimate of distance. Or we can half the distance and say light speed remains the same. It all depends on how elaborate the consensus theory is and whether this type of change will be cause a house of cards affect. If the change is hazardous, it may be better to fudge light speed limits, since huge sums of money needs to be justified for physics projects. This can cause the layman money giver to pause.
What?
Thats the problem with your argument. Truth does not change, our beliefs change. Theories are not truthful, they may have a very high level of validation/certainty, but they are never true. These theories can be mutated or falsified or improved upon, on the other hand truth stands.
My example was bingo. You are not a female, I thought based on certain observations and I believed that my theory is true that you are a female. My belief got falsified but truth remained the same.
On the OP why do you believe that FTL is ok, just because it is accepted by mainstream? Can you not have any alternative explanation for large redshifts as observed?
It is bad to bring in another thread issue without proper reference. Cite whatever you are claiming, you are a detective #1 here, do that.
Even otherwise how the hell it matters to you what I write to Paddoboy or James R. That should not prevent you from posting your POV, if at all you have any.
Good post, beyond posturing.
So in principle you are saying that in case of MW and andromeda the closing in motion between them is higher than that of expansion and you are also asserting that expansion is everywhere.
Now please consider a gravitationally bound orbital system. Consider any satellite Galaxy to our Milky Way (or even Earth Sun system), the Earth is in keplerial orbit with respect to Sun, this is equivalent to free fall but its an orbital motion. So if there is expansion of space between such objects, the system should beome unstable unless we can prove the following..
1. The fall of Earth towards Sun due to Gravitational Radiation or by any other means is just offsetted by Gravitational pull back.
Please understand that if the distance between the two increases due to expansion even momentarily, the gravitationally bonding reduces so chances of gravity winning the tug of war is less, and the orbital motion should become unstable. But it does not. Also please understand that we have developed capabilities to measure sub proton distances, so I am sure we can establish both the motions to a very good degree of precision. Have we done that?
If you have citation to counter this argument, then that would be great.
Posturing?
Correct.
I have no idea why you think the system would become unstable.
I don't know what that sentence means. What is gravitational pull back?
Momentary expansion? Why do you think that the orbits would become unstable?
I don't know, you should look it up if you are interested.
It seems that you are taking a counter position just to argue which is a waste of time. If you really are interested in this I suggest you look up the metric expansion of space.
Origin,
You are supporting the expansion and asserting that expansion is present everywhere but in case of gravitational bound system the gravitational closing in is more than the expansion. This is fine in case the object is falling and have no orbital motion.
But in case of orbital motion, the cosmological expansion is bound to create the instability. The larger systems (where the distance between the objects is large) will be pulled aprt due to cosmological expansion. Local system also stability is an issue due to cosmological expansion, however minute it may be. Study 2-body gravitational orbital motion in presence of cosmological expansion. You will get the idea.
You are supporting the expansion and asserting that expansion is present everywhere but in case of gravitational bound system the gravitational closing in is more than the expansion. This is fine in case the object is falling and have no orbital motion.
But in case of orbital motion, the cosmological expansion is bound to create the instability. The larger systems (where the distance between the objects is large) will be pulled aprt due to cosmological expansion. Local system also stability is an issue due to cosmological expansion, however minute it may be. Study 2-body gravitational orbital motion in presence of cosmological expansion. You will get the idea.
Why do you think that?
No, I don't get the idea. Please explain how a constant uniform expansion of 67 (km/s)/mPc will create instability in the orbit of the planets around the sun. It seems to me the solar wind would have more of an effect on the orbit of earth than expansion.
How is it uniform and constant? It is distance dependent and creates one more motion component over and above orbital motion. Take a stable orbit between a larger mass and smaller mass. All fine, now apply expansion, meaning the distance between the two got increased, it does not matter how small it is, sooner or later the objects will be pulled apart due to expansion.
I have no idea why you believe that.
Repeating the same thing over and over is not an explanation. If you give a logical explanation as to why you believe that I will respond otherwise - have a nice weekend.
Well then you have to study a bit more, it is somewhat more than being acquainted with the subject. Till then enjoy.
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