Galaxies going faster than light ? [v.2]

R

river

On the discovery science channel , that I'm watching now , has shown that galaxies in deep space or something is traveling faster than the speed of light !!!!!!.

It's on the series NASA’S UNEXPLAINED FILES .

Any body viewed this. Fascinating.
 
river said:
On the discovery science channel , that I'm watching now , has shown that galaxies in deep space or something is traveling faster than the speed of light !!!!!!.

It's on the series NASA’S UNEXPLAINED FILES .

Any body viewed this. Fascinating.
Click to expand...
Galaxies of course are not actually going FTL, rather from our perspective spacetime is expanding at that rate and apparently according to latest findings accelerating in that expansion.
http://www.universetoday.com/122768/how-are-galaxies-moving-away-faster-than-light/
 
Just quickly, the universal law that nothing can travel faster than light applies to anything with mass. Spacetime is not applicable in that sense.
 
paddoboy said:
Just quickly, the universal law that nothing can travel faster than light applies to anything with mass. Spacetime is not applicable in that sense.
Click to expand...

And yet galaxies or something is moving faster than light in deep space .

We're you able to watch the program ?
 
river said:
And yet galaxies or something is moving faster than light in deep space .

We're you able to watch the program ?
Click to expand...
I'm pretty sure you have misinterpreted it, or the program simply has it wrong.
Galaxies over larger scales are cosmologically red shifted, due to spacetime expansion and that expansion is accelerating and approaching, and indeed exceeding "c".
 
paddoboy said:
I'm pretty sure you have misinterpreted it, or the program simply has it wrong.
Galaxies over larger scales are cosmologically red shifted, due to spacetime expansion and that expansion is accelerating and approaching, and indeed exceeding "c".
Click to expand...

Watch the program pad ; don't forget pad ; these people didn't think that that FTL was possible either . It is NASA pad . NASA . Not just any organization. NASA .

IF you have a problem with this unexplained file from NASA ; I suggest you take it up with them .
 
river said:
Watch the program pad ; don't forget pad ; these people didn't think that that FTL was possible either . It is NASA pad . NASA . Not just any organization. NASA .

IF you have a problem with this unexplained file from NASA ; I suggest you take it up with them .
Click to expand...
Nothing with mass travels at or FTL river: Obviously either you misunderstand or just a case of poor journalism.
 
paddoboy - question; if something were on the "edge of the universe", is it not possible that, as the universe expands, that object (from a literally stationary reference point far away) could be travelling FTL, but from a relative vantage point (within the local cluster) it is travelling sub-light?

EG, if that region of spacetime itself is expanding away from the center of the universe at, and I'm pulling numbers out of my ass here, 80% the speed of light, and within that "slice" of space, the galaxy is moving towards its edge at 40% the speed of light, from our vantage point, would it not be moving at 120% the speed of light in relation to us?

Now... I have no qualms admitting that galactic dynamics etc are far beyond my area of expertise, so please pardon me for the all too simplified explanation of what I'm trying to say!

EDIT - Mod Note:
I have corrected the spelling of "going" in the thread title... simply because my apparent OCD was not allowing me to let it stay misspelled... go figure :)
 
paddoboy said:
No I do not question NASA and I know 100% certain that what you say is not what NASA has or would say.
Why not research it yourself, on a NASA site for example?
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You're wrong though pad ; get it through your head ; your wrong . Period.

So let me get this straight. You have not watched the program. So really you have no idea what the show is presenting as fact . The program has NASA SCIENTIST's AS PRESENTERS of this abnormality .

It is what it is pad; like or not .
 
river said:
You're wrong though pad ; get it through your head ; your wrong . Period.

So let me get this straight. You have not watched the program. So really you have no idea what the show is presenting as fact . The program has NASA SCIENTIST's AS PRESENTERS of this abnormality .

It is what it is pad; like or not .
Click to expand...
:) Whatever you say river.
So mass and us can go faster than light! Wow!!!! :D
The prime postulate of SR is wrong, Wow!:D
Einstein is wrong, Wow! :D
Every physicist/cosmologist over the last 100 years is wrong, Wow!! :D
And you, or the authors of the TV programm you were watching are getting this years Nobel prize for physics, Wow!! :D
You take it easy OK? :rolleyes:
 
river said:
You're wrong though pad ; get it through your head ; your wrong . Period.

So let me get this straight. You have not watched the program. So really you have no idea what the show is presenting as fact . The program has NASA SCIENTIST's AS PRESENTERS of this abnormality .

It is what it is pad; like or not .
Click to expand...

The problem is, something with mass travelling FTL violates some pretty basic principles of current physics... thus, it needs some seriously weighty evidence to back it up.

Do you recall the specific name of the episode?
 
And of course this expansion at FTL or in fact this expansion period, is only obvious and evident over the larger universal/spacetime scales, or near the edges of our Hubble volume and observable universe.
Our own local group of galaxies [M31, M33, our own Milky Way of course and around 30 other galaxies] as well as further afield, are gravitationally bound.
Explained by the simple fact that the gravity from these relatively denser regions of the universe, overcome the spacetime expansion.
 
paddoboy said:
And of course this expansion at FTL or in fact this expansion period, is only obvious and evident over the larger universal/spacetime scales, or near the edges of our Hubble volume and observable universe.
Our own local group of galaxies [M31, M33, our own Milky Way of course and around 30 other galaxies] as well as further afield, are gravitationally bound.
Explained by the simple fact that the gravity from these relatively denser regions of the universe, overcome the spacetime expansion.
Click to expand...

What ever makes you feel more intellectually comfortable pad .
 
Kittamaru said:
The problem is, something with mass travelling FTL violates some pretty basic principles of current physics... thus, it needs some seriously weighty evidence to back it up.

Do you recall the specific name of the episode?
Click to expand...
Kittamaru said:
The problem is, something with mass travelling FTL violates some pretty basic principles of current physics... thus, it needs some seriously weighty evidence to back it up.

Do you recall the specific name of the episode?
Click to expand...

Refer to my post # 1
 
Riv, the TV show is just barely scraping the surface of the physics. It is well-known, and is not a mystery or a paradox.

Einsteinian relativity says that nothing can travel faster than light locally.

What is happening is that our universe is expanding. The space between gravitationally unbound objects (such as galactic clusters) is increasing.

Relativity does not forbid this.

Wiki has a quick primer on superluminal recession:

The metric expansion of space is the increase of the distance between two distant parts of the universe with time. It is an intrinsic expansion whereby the scale of space itself changes.

While special relativity prohibits objects from moving faster than light with respect to a local reference frame where spacetime can be treated as flat and unchanging, it does not apply to situations where spacetime curvature or evolution in time become important. These situations are described by general relativity, which allows the separation between two distant objects to increase faster than the speed of light, although the definition of "distance" here is somewhat different to that used in an inertial frame. The definition of distance used here is the summation or integration of local comoving distances, all done at constant local proper time. For example, galaxies that are more than the Hubble radius, approximately 4.5 gigaparsecs or 14.7 billion light-years, away from us have a recession speed that is faster than the speed of light.

Because of the high rate of expansion, it is also possible for a distance between two objects to be greater than the value calculated by multiplying the speed of light by the age of the universe. These details are a frequent source of confusion among amateurs and even professional physicists.
Click to expand...
https://en.wikipedia.org/wiki/Metric_expansion_of_space
 
Kittamaru said:
The problem is, something with mass travelling FTL violates some pretty basic principles of current physics... thus, it needs some seriously weighty evidence to back it up.
Click to expand...
Yes simply the basic principal according to E=Mc2, that as one moves faster, one gains energy, hence mass.
Particles that have mass require energy to accelerate them. The closer to "c" a particle moves, the more energy is needed.
In essence, the faster you go, the heavier you get.
eg: If one chooses to accelerate a particle to light speed, you would need an infinite amount of energy, due to that particle becoming infinitely heavy.

river said:
What ever makes you feel more intellectually comfortable pad .
Click to expand...
The only thing that makes me comfortable is the fact that science explains everything logically according to evidence from the results of experiments and observations.
BTW, the show you refer to "NASA's Unexplained Files" is not by NASA, but by the Discovery/science channel people and akin to TV shows such as the X-Files, and simply go out of their way to sensationalize, and exaggerate certain supposed happenings by NASA astronauts and space endeavours, that are otherwise explained in more mundane logical reasonings.
One of their favourite "pastimes" is discussing sightings by astronauts and implying that they are UFO's of the Alien intelligent variety :)
Like I said, similar in content to the X-Files.
And yes most certainly, you can rest comfortably that whatever episode you were watching, that no galaxy was actually moving at or FTL [Doppler red shifted] but a simple observation of spacetime itself expanding and accelerating in that expansion [cosmological red shift]
 
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