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Posted: Sat Oct 15, 2005 8:10 am
by Jbuza
Theory of light has numerous times states, and it seems to be accepted that light traveles the same speed in all directions reguardless of the speed the body that produces the light is moving.

What causes red shift then? A slowing of the speed of light would cause a red shift woudln't it?

There is a red shift, but it is not explained by an expanding universe. And the red shift is the evidence that the universe is expaning.

Seems there is no real evidnece for an expanding universe at all.

Posted: Sat Oct 15, 2005 8:28 am
by Jbuza
The EPR experiment.

This experiment was devised by Albert Einstein, Boris Podolsky and Nathan Rosen (hence the 'EPR') as a thought experiment to 'prove' that quantum theory was incorrect. The technology did not exist then to actually carry out the experiment but Einstein believed, that in principle, it proved the 'foolishness' of quantum theory. The experiment was designed such that it would result in communication at faster than light speed, which Einstein's theory of relativity showed to be impossible. Neils Bohr's theory of quantum mechanics was at odds with Einstein's relativity, because it allowed instant communication between paired particles.

We have seen from our previous examination of this experiment (What is Quantum Mechanics?) that it has actually been carried out over a distance of 10 kilometres and confirmed as correct, instant communication did take place. Once again, we have a situation where, in the quantum world, the 'impossible', can take place, this time in the form of instant remote communication, which does of course mean that communication is taking place at faster than light speed.



Can light travelling at faster than light speed?

In a paper dated 19 July 2000 A team of scientists announced that they had succeeded in sending a pulse of light through a special chamber at a velocity faster than the speed of light. Scientists from the NEC Research Institute in Princeton, New Jersey, explain how they sent a pulse of light through a six centimetre chamber containing an unnatural form of cesium at the even more unnatural temperature of nearly absolute zero. The pulse of light travelled so fast that its peak actually exited the cesium chamber slightly before it entered. "No intuitive way to explain this observed effect precisely can be found because the 'specially prepared' atomic cell (cesium chamber) is in a state that does not exist naturally," write researchers Lijun Wang, Alexander Kuzmich and Arthur Dogariu in a statement. The team is quick to point out that their work does not violate Einstein's Theory of Special Relativity, which states that nothing can travel faster than the speed of light, because this would entail going backward in time. "More or less you can't go faster than the speed of light," said Wang. But the restriction that applies to things made of matter does not apply to light waves.

In fact, it was by using the waves of different colours of light to amplify each other and create the pulse that the researchers were able to get the light to warp through the cesium cell and reconstruct itself on the other side before it had entered. According to the researchers, the experiment also does not violate the principle of causality, which requires the cause of any effect to precede it in time. The fact that the peak of the pulse of light exits the chamber before it enters is the result of the light waves building a pulse on the other side of the cesium cell that is identical to the one entering it. So it is not exactly the same pulse. "This means that even if the 'effect' appears to precede the 'cause,' you still can't send information - such as news of an impending accident - faster than (the speed of light)," writes Jon Marango of the Imperial College in London, in a commentary on the work also appearing in Nature.'

http://www.thekeyboard.org.uk/Faster%20 ... 0speed.htm

Posted: Sat Oct 15, 2005 4:15 pm
by Felgar
Byblos wrote:I have considered that a great deal but I had to dismiss it as it tends to show God as a liar. Since we know God cannot lie, the theory can't be right. An example: If the universe is created already in motion then light was created in transition. This implies that the supernova we seem to be observing today that occurred millions of years ago did not actually happen. This smacks of deception.
Whether or not it happenned is just a matter of perception. God can create history as He is not bound by time. In an instant, God could backfill the universe's history. It gets back to causality - is God bounded by it? I don't think so.

What I like about this is that God can create the actual past along with the present, and also it is created such that it actually did happen. This is why we see so much uniform evidence for the solar system being 4.5 Billion years old and the universe being 13 or so. It actually IS that old - the entire fabric of the universe including time and history could have been created in a single instant. It actually DID happen, from the point of view of anyone bound by time and causality which we are.

Consider this: Has tomorrow already happenned? To God yes, to us no. It's the same thing just in reverse.

Besides, as already pointed out by Jbuza, the precedent is already set with Adam and Eve. Did God create a single fertilized cell and then cause it 'grow' naturally into a fetus, infant, child, and grown man? I doubt it, and we also know that He certainly didn't do that with Eve. If God didn't have Adam and Eve develop completely naturally, why would he do that with the universe itself?

Posted: Sat Oct 15, 2005 7:18 pm
by BGoodForGoodSake
Felgar wrote:
Byblos wrote:I have considered that a great deal but I had to dismiss it as it tends to show God as a liar. Since we know God cannot lie, the theory can't be right. An example: If the universe is created already in motion then light was created in transition. This implies that the supernova we seem to be observing today that occurred millions of years ago did not actually happen. This smacks of deception.
Whether or not it happenned is just a matter of perception. God can create history as He is not bound by time. In an instant, God could backfill the universe's history. It gets back to causality - is God bounded by it? I don't think so.

What I like about this is that God can create the actual past along with the present, and also it is created such that it actually did happen. This is why we see so much uniform evidence for the solar system being 4.5 Billion years old and the universe being 13 or so. It actually IS that old - the entire fabric of the universe including time and history could have been created in a single instant. It actually DID happen, from the point of view of anyone bound by time and causality which we are.

Consider this: Has tomorrow already happenned? To God yes, to us no. It's the same thing just in reverse.

Besides, as already pointed out by Jbuza, the precedent is already set with Adam and Eve. Did God create a single fertilized cell and then cause it 'grow' naturally into a fetus, infant, child, and grown man? I doubt it, and we also know that He certainly didn't do that with Eve. If God didn't have Adam and Eve develop completely naturally, why would he do that with the universe itself?
Again I see no problems with this, but personally I cannot easily accept this.

Posted: Sat Oct 15, 2005 7:23 pm
by BGoodForGoodSake
Jbuza wrote:Theory of light has numerous times states, and it seems to be accepted that light traveles the same speed in all directions reguardless of the speed the body that produces the light is moving.

What causes red shift then? A slowing of the speed of light would cause a red shift woudln't it?

There is a red shift, but it is not explained by an expanding universe. And the red shift is the evidence that the universe is expaning.

Seems there is no real evidnece for an expanding universe at all.
Lets use a siren as an example. When an ambulance approaches the pitch of the siren is higher than normal, as the ambulance passes the pitch becomes lower. The sound waves however travel at the roughly same rate throughout this whole sequence.

Light does precisely the same thing. In the visible light spectrum longer wavelengths are red and shorter ones are blue. When an object is moving away it will stretch the wavelength like the pitch lowering in a siren. The speed of the lightwave remains the same.

Posted: Sun Oct 16, 2005 12:52 am
by Felgar
BGoodForGoodSake wrote:Again I see no problems with this, but personally I cannot easily accept this.
Yeah, if you haven't first accepted by default both that God exists and that He's the God portrayed in the Bible, then it's really neither here nor there. To you the explanation must seem like just grasping at straws; I can understand that. Really I was more responding to Byblos...

Posted: Sun Oct 16, 2005 5:22 am
by Byblos
Felgar wrote:
Byblos wrote:I have considered that a great deal but I had to dismiss it as it tends to show God as a liar. Since we know God cannot lie, the theory can't be right. An example: If the universe is created already in motion then light was created in transition. This implies that the supernova we seem to be observing today that occurred millions of years ago did not actually happen. This smacks of deception.

Whether or not it happenned is just a matter of perception. God can create history as He is not bound by time. In an instant, God could backfill the universe's history. It gets back to causality - is God bounded by it? I don't think so.

What I like about this is that God can create the actual past along with the present, and also it is created such that it actually did happen. This is why we see so much uniform evidence for the solar system being 4.5 Billion years old and the universe being 13 or so. It actually IS that old - the entire fabric of the universe including time and history could have been created in a single instant. It actually DID happen, from the point of view of anyone bound by time and causality which we are.


I see what you mean. In that context I would tend to agree it is in the realm of possibility.
Felgar wrote:Consider this: Has tomorrow already happenned? To God yes, to us no. It's the same thing just in reverse.


I may have an issue with the above statement but I have a feeling this will open up a can of worms. In any case, let me try to explain my point of view. I believe completely and wholeheartedly in free will. It is the greatest gift that God bestowed upon us. As such, our future is determined one moment at a time according to our actions. If tomorrow has already occurred to God (i.e. if God knows what I will do tomorrow) would that not mean that my tomorrow is already pre-planned for me? By extension, would that not negate free will?
Felgar wrote:Besides, as already pointed out by Jbuza, the precedent is already set with Adam and Eve. Did God create a single fertilized cell and then cause it 'grow' naturally into a fetus, infant, child, and grown man? I doubt it, and we also know that He certainly didn't do that with Eve. If God didn't have Adam and Eve develop completely naturally, why would he do that with the universe itself?


That, of course, assumes the physical Adam and Eve were created. It can be argued that the creation of Adam and Eve was accomplished when God breathed a spirit into an already existing animal. That would reconcile with evolution (by design).

Posted: Sun Oct 16, 2005 5:39 am
by Jbuza
Byblos wrote:

That, of course, assumes the physical Adam and Eve were created. It can be argued that the creation of Adam and Eve was accomplished when God breathed a spirit into an already existing animal. That would reconcile with evolution (by design).
What is the evidence for this then? IT explains man's unique ability, and that he is a special creation. God took paticular attention in the creation of man. He said he created them in His image, and man was the only creature that He physically made, the others he created through His Word. How do you reconcile this with scripture?

Posted: Sun Oct 16, 2005 5:50 am
by Jbuza
Felgar wrote

Consider this: Has tomorrow already happenned? To God yes, to us no. It's the same thing just in reverse.

Byblos wrote

I may have an issue with the above statement but I have a feeling this will open up a can of worms. In any case, let me try to explain my point of view. I believe completely and wholeheartedly in free will. It is the greatest gift that God bestowed upon us. As such, our future is determined one moment at a time according to our actions. If tomorrow has already occurred to God (i.e. if God knows what I will do tomorrow) would that not mean that my tomorrow is already pre-planned for me? By extension, would that not negate free will?



Yeah that is something isn't it? The Bible clearly talks about predestination and free will. I have been toying with this idea about God being light. IT explains a great deal. If God were light, or at least like light, then he would exist outside time, and he would comprehend all of time, he would have infinite properties with respect to energy, size, and such.

Posted: Sun Oct 16, 2005 6:04 am
by Jbuza
BGoodForGoodSake wrote:
Jbuza wrote:Theory of light has numerous times states, and it seems to be accepted that light traveles the same speed in all directions reguardless of the speed the body that produces the light is moving.

What causes red shift then? A slowing of the speed of light would cause a red shift woudln't it?

There is a red shift, but it is not explained by an expanding universe. And the red shift is the evidence that the universe is expaning.

Seems there is no real evidnece for an expanding universe at all.
Lets use a siren as an example. When an ambulance approaches the pitch of the siren is higher than normal, as the ambulance passes the pitch becomes lower. The sound waves however travel at the roughly same rate throughout this whole sequence.

Light does precisely the same thing. In the visible light spectrum longer wavelengths are red and shorter ones are blue. When an object is moving away it will stretch the wavelength like the pitch lowering in a siren. The speed of the lightwave remains the same.
Yeah that is the doppler effect and has been clearly demonstrated with sound, but numerous tests with light indicate that this doesn't happen with light. Our best scientific tests indicate that the speed of light is the same reguardless of the fact that the planetary body is theorized to be moving away. The light should be traveling at the same speed away from us as it is towards us. The evidence of an expanding universe is pretty weak if it rests on this red shift. There should be no red shift the speed of the moving body should not effect the visible light.

Posted: Sun Oct 16, 2005 6:06 am
by Byblos
Jbuza wrote:
Byblos wrote:

That, of course, assumes the physical Adam and Eve were created. It can be argued that the creation of Adam and Eve was accomplished when God breathed a spirit into an already existing animal. That would reconcile with evolution (by design).


What is the evidence for this then? IT explains man's unique ability, and that he is a special creation. God took paticular attention in the creation of man. He said he created them in His image, and man was the only creature that He physically made, the others he created through His Word. How do you reconcile this with scripture?


It is reconciled by the very scriptural definition of man being made in the image of God. God does not have a physical appearance so the physical body is not what is meant by the image of God (Jesus took up a physical body so we can relate to him). It is the spiritual side (the spirit itself) that is made in the image of God (some of whose attributes are free will, conscience, morality, etc. These attributes do not exist in any living thing other than humans. That is the image of God).

Posted: Sun Oct 16, 2005 6:13 am
by Jbuza
The red shift is explained by a decrease in the speed of light, not by an expanding universe.

RECONSIDERING LIGHT-SPEED

It is at this point in the discussion that a consideration of light-speed becomes important. It has already been mentioned that an increase in vacuum energy density will result in an increase in the electrical permittivity and the magnetic permeability of space, since they are energy related. Since light-speed is inversely linked to both these properties, if the energy density of the vacuum increases, light-speed will decrease uniformly throughout the cosmos. Indeed, in 1990 Scharnhorst [51] and Barton [20] demonstrated that a lessening of the energy density of a vacuum would produce a higher velocity for light. This is explicable in terms of the QED approach. The virtual particles that make up the 'seething vacuum' can absorb a photon of light and then re-emit it when they annihilate. This process, while fast, takes a finite time. The lower the energy density of the vacuum, the fewer virtual particles will be in the path of light photons in transit. As a consequence, the fewer absorptions and re-emissions which take place over a given distance, the faster light travels over that distance [52, 53].

However, the converse is also true. The higher the energy density of the vacuum, the more virtual particles will interact with the light photons in a given distance, and so the slower light will travel. Similarly, when light enters a transparent medium such as glass, similar absorptions and re-emissions occur, but this time it is the atoms in the glass which absorb and re-emit the light photons. This is why light slows as it travels through a denser medium. Indeed, the more closely packed the atoms, the slower light will travel as a greater number of interactions occur in a given distance. In a recent illustration of this light-speed was reduced to 17 metres/second as it passed through extremely closely packed sodium atoms near absolute zero [54]. All this is now known from experimental physics. This agrees with Barnett's comments in Nature [11] that 'The vacuum is certainly a most mysterious and elusive object…The suggestion that the value of the speed of light is determined by its structure is worthy of serious investigation by theoretical physicists.'

On the new model,the redshift measurements imply that light-speed, c, is dropping exponentially. For each redshift quantum change, the speed of light has apparently changed by a significant amount. The precise quantity is dependent upon the value adopted for the Hubble constant which links a galaxy's redshift with its distance.

AN OBSERVED DECLINE IN LIGHT-SPEED

The question then arises as to whether or not any other observational evidence exists that the speed of light has diminished with time. Surprisingly, some 40 articles about this very matter appeared in the scientific literature from 1926 to 1944 [56]. Some important points emerge from this literature. In 1944, despite a strong preference for the constancy of atomic quantities, N. E. Dorsey [57] was reluctantly forced to admit: 'As is well known to those acquainted with the several determinations of the velocity of light, the definitive values successively reported … have, in general, decreased monotonously from Cornu's 300.4 megametres per second in 1874 to Anderson's 299.776 in 1940 …' Even Dorsey's own re-working of the data could not avoid that conclusion.

However, the decline in the measured value of 'c' was noticed much earlier. In 1886, Simon Newcomb reluctantly concluded that the older results obtained around 1740 were in agreement with each other, but they indicated 'c' was about 1% higher than in his own time [58], the early 1880's. In 1941 history repeated itself when Birge made a parallel statement while writing about the 'c' values obtained by Newcomb, Michelson, and others around 1880. Birge was forced to concede that '… these older results are entirely consistent among themselves, but their average is nearly 100 km/s greater than that given by the eight more recent results' [59]. Each of these three eminent scientists held to a belief in the absolute constancy of 'c'. This makes their careful admissions about the experimentally declining values of measured light speed more significant.

EXAMINING THE DATA

The data obtained over the last 320 years at least imply a decay in 'c' [56]. Over this period, all 163 measurements of light-speed by 16 methods reveal a non-linear decay trend. Evidence for this decay trend exists within each measurement technique as well as overall. Furthermore, an initial analysis of the behaviour of a number of other atomic constants was made in 1981 to see how they related to 'c' decay. On the basis of the measured value of these 'constants', it became apparent that energy was being conserved throughout the process of 'c' variation. In all, confirmatory trends appear in 475 measurements of 11 other atomic quantities by 25 methods. Analysis of the most accurate atomic data reveals that the trend has a consistent magnitude in all the other atomic quantities that vary synchronously with light-speed [56].

All these measurements have been made during a period when there have been no quantum increases in the energy of atomic orbits. These observations reinforce the conclusion that, between any proposed quantum jumps, energy is conserved in all relevant atomic processes, as no extra energy is accessible to the atom from the ZPF. Because energy is conserved, the c-associated atomic constants vary synchronously with c, and the existing order in the cosmos is not disrupted or intruded upon. Historically, it was this very behaviour of the various constants, indicating that energy was being conserved, which was a key factor in the development of the 1987 Norman-Setterfield report, The Atomic Constants, Light And Time [56].

The mass of data supporting these conclusions comprises some 638 values measured by 43 methods. Montgomery and Dolphin did a further extensive statistical analysis on the data in 1993 and concluded that the results supported the 'c' decay proposition if energy was conserved [60]. The analysis was developed further and formally presented in August 1994 by Montgomery [61]. These papers answered questions related to the statistics involved and have not yet been refuted.

http://www.ldolphin.org/setterfield/redshift.html

Posted: Sun Oct 16, 2005 6:15 am
by Byblos
Jbuza wrote:Felgar wrote

Consider this: Has tomorrow already happenned? To God yes, to us no. It's the same thing just in reverse.

Byblos wrote

I may have an issue with the above statement but I have a feeling this will open up a can of worms. In any case, let me try to explain my point of view. I believe completely and wholeheartedly in free will. It is the greatest gift that God bestowed upon us. As such, our future is determined one moment at a time according to our actions. If tomorrow has already occurred to God (i.e. if God knows what I will do tomorrow) would that not mean that my tomorrow is already pre-planned for me? By extension, would that not negate free will?



Yeah that is something isn't it? The Bible clearly talks about predestination and free will. I have been toying with this idea about God being light. IT explains a great deal. If God were light, or at least like light, then he would exist outside time, and he would comprehend all of time, he would have infinite properties with respect to energy, size, and such.
Very interesting. We should create a new thread for this and discuss it further. We already know God is outside time or space and not bound by them but can you expand on your ideas a little more?

Posted: Sun Oct 16, 2005 7:40 am
by BGoodForGoodSake
Jbuza wrote:The red shift is explained by a decrease in the speed of light, not by an expanding universe.

RECONSIDERING LIGHT-SPEED

It is at this point in the discussion that a consideration of light-speed becomes important. It has already been mentioned that an increase in vacuum energy density will result in an increase in the electrical permittivity and the magnetic permeability of space, since they are energy related. Since light-speed is inversely linked to both these properties, if the energy density of the vacuum increases, light-speed will decrease uniformly throughout the cosmos. Indeed, in 1990 Scharnhorst [51] and Barton [20] demonstrated that a lessening of the energy density of a vacuum would produce a higher velocity for light. This is explicable in terms of the QED approach. The virtual particles that make up the 'seething vacuum' can absorb a photon of light and then re-emit it when they annihilate. This process, while fast, takes a finite time. The lower the energy density of the vacuum, the fewer virtual particles will be in the path of light photons in transit. As a consequence, the fewer absorptions and re-emissions which take place over a given distance, the faster light travels over that distance [52, 53].

However, the converse is also true. The higher the energy density of the vacuum, the more virtual particles will interact with the light photons in a given distance, and so the slower light will travel. Similarly, when light enters a transparent medium such as glass, similar absorptions and re-emissions occur, but this time it is the atoms in the glass which absorb and re-emit the light photons. This is why light slows as it travels through a denser medium. Indeed, the more closely packed the atoms, the slower light will travel as a greater number of interactions occur in a given distance. In a recent illustration of this light-speed was reduced to 17 metres/second as it passed through extremely closely packed sodium atoms near absolute zero [54]. All this is now known from experimental physics. This agrees with Barnett's comments in Nature [11] that 'The vacuum is certainly a most mysterious and elusive object…The suggestion that the value of the speed of light is determined by its structure is worthy of serious investigation by theoretical physicists.'

On the new model,the redshift measurements imply that light-speed, c, is dropping exponentially. For each redshift quantum change, the speed of light has apparently changed by a significant amount. The precise quantity is dependent upon the value adopted for the Hubble constant which links a galaxy's redshift with its distance.

AN OBSERVED DECLINE IN LIGHT-SPEED

The question then arises as to whether or not any other observational evidence exists that the speed of light has diminished with time. Surprisingly, some 40 articles about this very matter appeared in the scientific literature from 1926 to 1944 [56]. Some important points emerge from this literature. In 1944, despite a strong preference for the constancy of atomic quantities, N. E. Dorsey [57] was reluctantly forced to admit: 'As is well known to those acquainted with the several determinations of the velocity of light, the definitive values successively reported … have, in general, decreased monotonously from Cornu's 300.4 megametres per second in 1874 to Anderson's 299.776 in 1940 …' Even Dorsey's own re-working of the data could not avoid that conclusion.

However, the decline in the measured value of 'c' was noticed much earlier. In 1886, Simon Newcomb reluctantly concluded that the older results obtained around 1740 were in agreement with each other, but they indicated 'c' was about 1% higher than in his own time [58], the early 1880's. In 1941 history repeated itself when Birge made a parallel statement while writing about the 'c' values obtained by Newcomb, Michelson, and others around 1880. Birge was forced to concede that '… these older results are entirely consistent among themselves, but their average is nearly 100 km/s greater than that given by the eight more recent results' [59]. Each of these three eminent scientists held to a belief in the absolute constancy of 'c'. This makes their careful admissions about the experimentally declining values of measured light speed more significant.

EXAMINING THE DATA

The data obtained over the last 320 years at least imply a decay in 'c' [56]. Over this period, all 163 measurements of light-speed by 16 methods reveal a non-linear decay trend. Evidence for this decay trend exists within each measurement technique as well as overall. Furthermore, an initial analysis of the behaviour of a number of other atomic constants was made in 1981 to see how they related to 'c' decay. On the basis of the measured value of these 'constants', it became apparent that energy was being conserved throughout the process of 'c' variation. In all, confirmatory trends appear in 475 measurements of 11 other atomic quantities by 25 methods. Analysis of the most accurate atomic data reveals that the trend has a consistent magnitude in all the other atomic quantities that vary synchronously with light-speed [56].

All these measurements have been made during a period when there have been no quantum increases in the energy of atomic orbits. These observations reinforce the conclusion that, between any proposed quantum jumps, energy is conserved in all relevant atomic processes, as no extra energy is accessible to the atom from the ZPF. Because energy is conserved, the c-associated atomic constants vary synchronously with c, and the existing order in the cosmos is not disrupted or intruded upon. Historically, it was this very behaviour of the various constants, indicating that energy was being conserved, which was a key factor in the development of the 1987 Norman-Setterfield report, The Atomic Constants, Light And Time [56].

The mass of data supporting these conclusions comprises some 638 values measured by 43 methods. Montgomery and Dolphin did a further extensive statistical analysis on the data in 1993 and concluded that the results supported the 'c' decay proposition if energy was conserved [60]. The analysis was developed further and formally presented in August 1994 by Montgomery [61]. These papers answered questions related to the statistics involved and have not yet been refuted.

http://www.ldolphin.org/setterfield/redshift.html
Is this a linear decay?

Posted: Sun Oct 16, 2005 10:19 am
by Jbuza
Not sure if it is linear, need more information. Found this seems very informative to me. Just posted a bit, but the link is here.

Red Shift Riddles


The fact that red shifts appear to be quantized has interesting implications for the study of the universe. This suggests that the red shift may be caused by something other than the expansion of the universe, at least in part. This could be a loss of energy of light rays as they travel, or a decrease in the speed of light through discrete levels. Maybe there is some other explanation.
The following quotation concerning this phenomenon is from "Quantized Galaxy Redshifts" by William G. Tifft & W. John Cocke, University of Arizona, Sky & Telescope Magazine, Jan., 1987, pgs. 19-21. I thank Mark Stewart for this material:

As the turn of the next century approaches, we again find an established science in trouble trying to explain the behavior of the natural world. This time the problem is in cosmology, the study of the structure and "evolution" of the universe as revealed by its largest physical systems, galaxies and clusters of galaxies. A growing body of observations suggests that one of the most fundamental assumptions of cosmology is wrong.

Most galaxies' spectral lines are shifted toward the red, or longer wavelength, end of the spectrum. Edwin Hubble showed in 1929 that the more distant the galaxy, the larger this "redshift". Astronomers traditionally have interpreted the redshift as a Doppler shift induced as the galaxies recede from us within an expanding universe. For that reason, the redshift is usually expressed as a velocity in kilometers per second.

http://www.cs.unc.edu/~plaisted/ce/redshift.html