Viewing galaxies receding faster than light

[Paddypdx]

If galaxies are receding from us at faster than the speed of light how can we see them?

 

[rod]

Good question. From what I understand, we can only see the galaxies at their look back time distance (Special Relativity) in the BB model, not their present, comoving radial distance from Earth. I recently learned that all objects with redshifts => 1.4 are moving away faster than c velocity because of their comoving radial distances using BB model expansion metrics. So quasars with redshifts of 2 or 3, all zipping away faster than c velocity because 3D space is expanding fast than c velocity. The CMBR is said to have redshift ~ 1100, so today, the edge of the universe is some 46 or 46.5 billion light years distant from Earth, so the universe diameter is about 93 billion light years across. You can use the cosmology calculators to check various *features* in the BB model

Cosmology Calculators (caltech.edu)

Cosmology calculator | kempner.net

As a telescope user (I have two and use all the time), how does science, verify and measure that objects in the universe today are expanding in 3D space, faster than c velocity? This must hold true for any object with z => 1.4. I know using my telescopes I cannot see or directly verify such expansion claims

 

[Helio]

If galaxies are receding from us at faster than the speed of light how can we see them?

Oddly enough, regions that are only just a little faster than c will be visible since their light will reach the "slower than light" expansion region, thus will become visible.

It's not intuitive, admittedly.

 

[Atlan0001]

If galaxies are receding from us at faster than the speed of light how can we see them?

The easiest question in the universe to answer, and the most obvious answer, though there are few, very few, who recognized, or even will recognize, the answer for what it is.

The speed of light is a fixed constant, we know that. Nothing can travel faster than it, locally relatively speaking. But there also exists a principle called the "principle of uncertainty" that many think applies solely to the micro-verse and particles. They are dead wrong. It applies to any object's position and velocity and distance -- the speed of light is a fixed constant -- and most especially any closing or opening in distance in space-time, which warps space-time singularity into space-time plurality for all observers of the object at any distance(s).

Per the speed of light being a fixed constant no observer can ever observe the reality of any object at any distance from that observer. This fact breaks down the observer's observational relativity to the object into "uncertainty." It breaks down the real and unobservable universe into multiple relative and observable "space-time" universes for multiple observers variable in distances from the object.

The reality of the object is a matter of the unobservable, the dark, universe regarding all observers at any distance from the object due to the fixed constancy of the speed of light. All observers at a distance are relative to the cartoon object existing in the light only during the time in took, or takes, light to go from the object to the observer. Light doesn't go instantaneously from object to observer, it takes time, and that time warps elastically little to largely depending upon distances light traveled.

You never observe the reality of any galaxy at a distance, only the cartoonishly relative, the elastically relative, galaxy in the light delivered to you per the fixed constant of the speed of light. So you have to triangulate "space-time" if you think you can, you and the real object unobserved and unobservable, and the relative object in the light and behind your reals in time (due to the fixed constant of the speed of light), all the way to billions and billions of years behind "real-time" -- thus eventually, inevitably, disappearing into oblivion in points -- in time.

A galaxy, or any other traveler, can distance itself from Earth faster than the speed of light relative to the measurement of the constant of it on Earth. That traveler will never be traveling faster than the speed of light locally to it. But of course the reality of that traveler locally in its own space-time is not relative to your locality locally in your own space-time. Your cartoon galaxy, or even Star Trek's Enterprise if that were possible, would be long gone -- long, long, gone -- from wherever you are observing and locating it in the universe in your own reality of space-time. To you, as a distant observer, that is elastically faster than the speed of light, elastically faster even than time, though in the fact of the matter it is no such thing. It is only "uncertainty," as a matter of the "principle of uncertainty" taking over at the macro-verse level.... taking over really and largely. The greater and greater in space-time a distance grows, the greater a redshift grows, that is the elasticity of relativity's cartoon-like space-time -- in the light -- and the elasticity of the shift of the light. The lesser, and lesser, a distance closes to any observer, the lesser and lesser a redshift -- that is the elasticity of relativity's cartoon-like space-time -- in the light -- and the elasticity of the shift of the light.

Nothing, no object, no localized reality of any object, in what I described above got any closer to the speed of light -- locally to it -- than 300,000kps (rounded off of course).

 

[Helio]

There are some websites that should be able to illustrate why we can see light from distant regions that are expanding faster than light. I once used an ant and a strip of rubber.

Imagine nailing one end of a long strip of rubber and then pulling on the other end of the rubber band.... at a constant rate. Imagine an ant on the fast end slowly walking toward the nailed end. Since the rate on the rubber band expanding is fixed, the ant will march inch by inch into regions that will be expanding slower.

This is because the rate is in kps per Mpc. So if the ant (light) starts at a distance where the kps is, say, a little faster than c, then as it inches forward it will be on a section of rubber band that will have the same rate but not the same net velocity since the distance is less. But the ant must be quick enough (i.e. close enough to the region traveling at c) so that the net is to its benefit in getting to the other end.

[Added: Here is a site that should help.]

 

[Atlan0001]

As a postscript to my post #4 above, I perceive due to the fact that every object in the universe from micro-verse particles on up through the macro-verse, regardless of the appearance of the opposite regarding all observed objects receding away from us at ever greater distances from us gradually slowing down to virtual, inanimate, stop action at the far ends, is in motion, in animation -- of one kind or another, and thus there exists in reality a singular "bent to infinity" to the space-time of that plural totality of motion -- that infinite build up of "uncertainty" ("uncertainties"), in space and time.

It is said that an inevitability of "entropy" is building up in our universe. But what we observe of the universe in large aspect is exactly the opposite; from a most "entropic universe" (inanimate stop action universe) at the far end reaches of observation to an ever more "energetic universe" (animated universe) everywhere close up here and now.. What is claimed -- predicted -- for the future of the universe is exactly the opposite of what progression is actually observed regarding the universe at large.
----------------------------

It is a Multiverse Universe.

 

[Atlan0001]

There are some websites that should be able to illustrate why we can see light from distant regions that are expanding faster than light. I once used an ant and a strip of rubber.

Imagine nailing one end of a long strip of rubber and then pulling on the other end of the rubber band.... at a constant rate. Imagine an ant on the fast end slowly walking toward the nailed end. Since the rate on the rubber band expanding is fixed, the ant will march inch by inch into regions that will be expanding slower.

This is because the rate is in kps per Mpc. So if the ant (light) starts at a distance where the kps is, say, a little faster than c, then as it inches forward it will be on a section of rubber band that will have the same rate but not the same net velocity since the distance is less. But the ant must be quick enough (i.e. close enough to the region traveling at c) so that the net is to its benefit in getting to the other end.

[Added: Here is a site that should help.]

What you are actually saying is that the ant, no matter where in the universe it is, is in the same room with the observer. That visibility, observability, is instantaneous throughout the universe. That there is only one ant and it is both the real ant and the relative ant, one and the same ant at one and the same time. That there is no other ant than one, real or relative -- and that there is no such thing as a principle of uncertainty vis-a-vis the macro-verse. That there is no such thing as the reaches of the invisible, unobservable, essentially 'quantum entangled' universe of space "now". that it is actually the reality of the one and one only ant that itself , really, slows down in time, watched nearly instantaneously to do so by the observer never more than one inch, not even that one inch, from it (being essentially simultaneous with it in the same room in fact not one inch from it).

This, the above, only because you never once mentioned the fact that there is actually more than one ant to the actual, relative, stage, the actual relative scenario universe which progressively splits in two, and into ever more splits (breaks down into two, and yet into even more than just two "relative" universes and ants and rubber bands.

As I see it, not to offend, your single ant and the single rubber band it walks, in your scenario, is nothing more than a relative illusion of light.

 

[Atlan0001]

I suppose I have to have a traveler take to interstellar space (versus the observer on Earth, and so on), to explain why "faster than light is meaningless" in an open system.

First, space of the universe is the dark universe for the traveler. Forget it, it is irrelevant herein. The traveler has not a clue as to his position and velocity in the dark universe.

Now turn on the lights of countless stars and galaxies, which will be nothing but distant points and clouds of light as far as the traveler traveling between them is concerned. Their light show is effectively points and clouds of time, not space, to the traveler. So the traveler is a time traveler as well as a space traveler. And this is why he has no concern for the speed of light except in his own immediate vicinity. Light from the surrounding universe at large becomes entirely a matter of time and time travel for the space-time traveler.. H. G. Wells and all his admirers, including mathematicians and physicists, were dead wrong in their view of a time machine and time travel. Any spaceship traveling interplanetary or interstellar, or intergalactic, space is the time machine, the beings aboard, time travelers.

A traveler reaches Alpha Centauri in four days, he didn't travel faster than the speed of light as far as space-time is concerned because the sun of our solar system he observes in the distance is four years and change from him. In getting to Alpha Centauri in four days by his ship's clock, he space-time traveled, relatively speaking, four + years and four days from Earth. Local to him, a space-time traveling (a time traveling) speed slower than the speed of light since it took four days longer than four+ years to travel four+ light years to Alpha Centauri.

An observer on Earth, if he could resolve light enough with his super scope, would see the traveler's arrival in the region of Alpha Centauri in four+ years and four days. That observer would also observe that the traveler had aged only four days in that four+ years and four days. And, that the traveler's clock aboard ship had advanced in time only four days in that same four+ years and four days of time. What the observer on Earth would witness for the traveler would be time slowing down for the traveler receding from him toward Alpha Centauri in the universe in the extreme. Of course the traveler would observe the observer on Earth to have backed up in time, retreated in time, four+ years in four days, since his home planet Sun would be four+ light years (a minus of four years) from him in the region of Alpha Centauri. He, himself, would be observed by him to not have left Earth yet. No violation of causality has taken place since there are two Earths in the space-time game, the one in the unobserved and unobservable dark, and the other in the light. He, himself, had observed Alpha Centauri to advance forward in time four+ years (a fast forwarding movie in time) in four days according to his shipboard clock. So the space traveler is at once a time traveler, never once traveling faster than the speed of light, really speaking. Forward he traveled forward in time, apparently. Rearward, he traveled rearwardly in time, apparently. The common denominator of that simultaneous forward / rearward apparent time travel.... the net constant / result for the exchange one for the other, t=0. And the speed of light in and at the distantly constant -- collapsed -- universe horizon holding constant for all travelers at all times, a stop action c=0 (dual dimensionality: the constant of speed 'c' being at one and the same time the Universe's constant of speed '0'. Closed systemically, approach 'c'; approach '0'. Reach 'c'; reach '0' (c = 300,000kps = 0)).
------------------

It is a Multiverse Universe.

A triple feature exists, I suppose:

Big Bang / Big Crunch / Big Vacuum
(Energy / Mass / C^2)
(E = MC^2)
(M = E/C^2)
(Energy / Mass / C^2)
Big Bang / Big Crunch / Big Vacuum

And I'm not forgetting Big Mirror mirroring to infinity.

It is a Multiverse Universe.