Interesting Theory and Analysis, But I Want More
The author's contention is that Einstein ignored light refraction through the Earth's atmosphere when he desires used a method for validating his General Theory of Relativity in 1919. The author's analysis is compelling as we all learned about light refraction in science class with a pencil in a glass of water. However, it will make more research on my part to completely agree that Einstein's theory is to be dismissed based on this one test alone. (Customer Reviews-Verified Purchase)
LENSING BY REFRACTION, NOT GRAVITY.
Professor R. C. Gupta at the Institute of Engineering & Technology in Lucknow, India has presented such a theory in a paper entitled, “Bending of Light Near a Star and Gravitational Red/Blue Shift: Alternative Explanation Based on Refraction of Light.”
The paper asserts that the theory behind gravitational lensing — one of the evidentiary “proofs” of General Relativity — is wrong, and that the lensing effect is caused by refraction through the “atmospheres” of stars and galaxies.
The paper also presents the mathematical basis for refraction and shows that refraction closely predicts the same lensing effect as attributed to gravity.
1.Is the cosmological redshift real, or is it an optical illusion caused by dust ?
The cosmological redshift seems to be real enough. For more about it see my article in Sky and Telescopemagazine, February 1993, which gives some background on how to interpret this phenomenon.
As the article explains, there are three ways that nature seems to be able to shift the wavelengths of spectral lines from atoms. The familiar Doppler shift is the one we all know from the passing siren. When it approaches, its pitch is higher than when it moves away from us. What works for sound waves also works for light waves, and we can see the Doppler shifts in the light from stars that orbit one another in space.
Einstein's theory of general relativity predicts two new ways of doing the same trick that don't involve motion as we normally think of it.
The gravitational redshift happens when light tries to escape from a gravitational field. This is actually a phenomenon that you can explain using ordinary newtonian physics. Thanks to Einstein's famous E= m c squared, and Planck's equally famous law relating the energy of light to its frequency, E = h x frequency, we can see that as a particle of light ( photon) moves out of a gravitational field, it must loose energy working against the gravitational field. Since photons always travel at the speed of light, the only place where this energy loss can show up is in a change of frequency. The frequency of the photon must decrease so that the energy carries by the photon is lower, and this corresponds to a 'red shift' to longer wavelengths. This phenomenon has been confirmed in laboratory experiments carried out by Pound and Rebka at Harvard University over 30 years ago. It's not a theory, its real.
Even more bizarre than the gravitational redshift is the so-called cosmological redshift. There is no known way to independently test for this because we cannot create a system as big as the universe to compare against. But we can look at other aspects of general relativity and see whether it gives the right results. All tests to date seem to suggest that general relativity is in pretty good shape, so that gives us confidence that something like the cosmological redshift might be a reality. Astronomical observations of distant galaxies reveal that we cannot explain their redshifts by either the Doppler or gravitational redshift mechanisms without ending up with unphysical answers. General relativity, in the guise of Big Bang cosmology, however, predicts just what we are seeing in terms of the redshift caused by the expansion of space. It's not an optical illusion any more than E=mc squared is. And it cannot be produced by any known mechanism that does not in some way have to do with gravitational fields.
2.Gravitational redshift.
In astrophysics, gravitational redshift or Einstein shift is the process by which electromagnetic radiation originating from a source that is in a gravitational field is reduced in frequency, or redshifted, when observed in a region of a weaker gravitational field. This is a direct result of gravitational time dilation - as one moves away from a source of gravitational field, the rate at which time passes is increased relative to the case when one is near the source. As frequency is inverse of time (specifically, time required for completing one wave oscillation), frequency of the electromagnetic radiation is reduced in an area of a lower gravitational field (i.e., a higher gravitational potential). There is a corresponding reduction in energy when electromagnetic radiation is red-shifted, as given by Planck's relation, due to the electromagnetic radiation propagating in opposition to the gravitational gradient. There also exists a corresponding blueshift when electromagnetic radiation propagates from an area of a weaker gravitational field to an area of a stronger gravitational field.
The gravitational redshift of a light wave as it moves upwards against a gravitational field (produced by the yellow star below). The effect is greatly exaggerated in this diagram.
If applied to optical wavelengths, this manifests itself as a change in the colour of visible light as the wavelength of the light is increased toward the red part of the light spectrum. Since frequency and wavelength are inversely proportional, this is equivalent to saying that the frequency of the light is reduced towards the red part of the light spectrum, giving this phenomenon the name redshift.
(wikipedia.org )
In general relativity, Einstein ignored light refraction, and proving method isn't scientific and deeply wrong.
Einstein proposed therefore, that photographs be taken of the stars immediately bordering the darkened face of the sun during an eclipse and compared with photographs of those same stars made at another time. According to his theory, the light from the stars surrounding the sun should be bent inward, toward the sun, in traversing the sun’s gravitational field; hence the images of these stars should appear to observer on earth to be shifted outward from their usual positions in the sky.
The proving method for hypothesis as suggested by Einstein as the theory founder should not be able to be carried out, considering the fact that in scientific exposure in astronomy, the instant observation applies. It means, all calculations to determine the ‘true position’ and the ‘apparent position’ of a certain star at the sky is only applicable at a certain time and at a certain place on which such observation is performed.
The observation on a star conducted twice from the places with different geographical positions will result the different height/altitude and azimuth of the star. The altitude and azimuth of a star indicates the position of the star at the time when the observation is performed. The altitude and azimuth of a star changes every time due to the daily movement of the said space objects.
Therefore, the proving method as conducted by Arthur Eddington, should not be able to be performed. Moreover, the observation / photo taking for the stars were performed twice with sufficiently long different interval of time.
In astronomy, the light deviation is something very common, and not caused by gravity field of a massive object, but it occurs due to the light refraction. Light refraction causes the light of all objects in the sky reaching the earth and seen by the observers, has been deviated by the media to pass through, including the light bending by the earth atmosphere.
The magnitude of light deviation in astronomy is known as 'Astronomical Refraction' and 'Terrestrial Refraction'.
It is really hard to understand that the proving method was conducted by a team led by Arthur Eddington.
The Cosmological Redshift causes by light refraction, not gravity.
General Relativity has been wrong since the beginning. There is no 'Gravitational redshift', but 'The Cosmological Redshift' causes by light refraction, not gravity. The cosmological redshift actually a mirage.
Mirages are not optical illusions, as many people think. They are real phenomena of atmospheric optics, caused by strong ray-bending in layers with steep thermal gradients. Because mirages are real physical phenomena, they can be photographed.
Common misconceptions.It is incorrect to say (as even some textbooks do) that a mirage is an image in the wrong place, because atmospheric refraction displaces almost everything we see from its geometric position — that is, rays of light in the lower atmosphere are usually curved, because the density of air usually decreases steadily with increasing height. Thus, everything normally appears displaced slightly above its geometric or “true” position. This displacement is known as terrestrial refraction when the object is inside the atmosphere, and astronomical refraction when it is beyond the atmosphere. While these effects are usually small enough to escape casual observation with the naked eye, they are very severe problems in fields such as geodesy and positional astronomy, because they can be hundreds or even thousands of times larger than measurement errors.(www-rohan.sdsu.edu)
What causes a mirage?
Edwin Meyer, a physics professor at Baldwin-Wallace College, explains.
To understand how a mirage forms, one must first understand how light
travels through air. If the air is all the same temperature--cold or
hot--light travels through it in a straight line.
If a steady temperature gradient exists, however, light will follow a
curved path toward the cooler air. The standard freshman physics
explanation for this phenomenon is that cold air has a higher index of
refraction than warm air does. As a result, photons (particles of light)
travel through hot air faster than they can through cold air because
the hot air is less dense. The quantum electrodynamics explanation is
that photons always take the path of minimum time when traveling from
one point to another. In order to get from one point to another in a
minimum time, photons will take "shortcuts" even though the length of
the path is curved and it covers a longer distance than the direct
route.
Mirages are a direct result of photons taking the path of minimum
time in vertical temperature gradients. Ideal conditions for a mirage
are still air on a hot, sunny day over a flat surface that will absorb
the sun's energy and become quite hot. When these conditions exist, the
air closest to the surface is hottest and least dense and the air
density gradually increases with height. Incoming photons take a curved
path from the sky to the viewer's eye. The illusion comes from the fact
that quantum electrodynamics is not intuitive and the human brain
assumes that light travels in a straight line. A viewer looking at, say,
the road ahead on a hot, still, day will see the sky because photons
from the sky are taking the curved path that minimizes the time taken.
The brain interprets this as water on the road because water would
reflect light from the sky in much the same way that a vertical
temperature gradient does.
A simple experiment can demonstrate the manner in which a light beam bends in a vertical density gradient. Fill a long glass tank with water, dissolve sugar in the water and shine a laser beam in one end. The vertical gradient produced by the sugar concentration will cause the beam to bend. If the tank is long enough and a mirror is placed on the bottom, the beam will "bounce" along the bottom of the tank.
( scientificamerican.com )
More about Astronomy:
1.Light bending/deviation is the difference between Hc and Ho
Taking a sight using the intercept method (Marcq St. Hilaire)consists of the following process:
Observe the altitude above the horizon Ho of a celestial body and note the time of the observation.Assume a certain geographical position (lat., lon.), it does not matter which one so long as it is within, say, 50 NM of the actual position (or even 100 NM would not introduce too much error). Compute the altitude Hc and azimuth Zn with which an observer situated at that assumed position would observe the body.
If the actual observed altitude Ho is smaller than the computed altitude Hc this means the observer is farther away from the body than the observer at the assumed position, and vice versa. For each minute of arc the distance is one NM and the difference between Hc and Ho expressed in minutes of arc (which equal NM) is termed the "intercept". The navigator now has computed the intercept and azimuth of the body.
On the chart he marks the assumed position AP and draws a line in the direction of the azimuth Zn. He then measures the intercept distance along this azimuth line, towards the body if Ho>Hc and away from it if Ho<Hc. At this new point he draws a perpendicular to the azimuth line and that is the line of position LOP at the moment of the observation.
The reason that the chosen AP is not important (within limits) is that if a position closer to the body is chosen then Hc will be greater but the distance will be measured from the new AP which is closer to the body and the end resulting LOP will be the same.
The relevant formulas (derived using the spherical trigonometric identities) are:
Where
Hc = Computed altitude
Zn = Computed azimuth
lat = Latitude
dec = Declination
LHA = Local Hour Angle
(wikipedia.org/wiki/Intercept_method)
2.Determining Position Using a Sextant
We are quite spoiled in this modern age of GPS: We always know our exact position on the surface of the earth, and we never have to pick up a calculator to figure it out. I recently counted the GPS devices aboard Three@Sea and discovered that there are eight of them! Except in extraordinary circumstances, I have confidence that one of our on-board devices will be able to tell us (or a search party) where we are.
But what about extraordinary circumstances? What if we experience a catastrophic lightening strike that takes out all of our electronics? What if a massive solar flare disables the global GPS system for awhile? And there are probably a few other scenarios under which GPS might become temporarily unavailable. If one of these extreme scenarios occurs while we’re in the middle of the Pacific Ocean, we would like to be able to figure out where we are, primarily so we can get to where we’re going.
Okay — I doubt any of those catastrophic things will happen. But I’m a geek with a scientific curiosity about celestial navigation, as well as a certain nostalgia for the ways of the ancient mariner. So about six months ago I decided to learn the basics of using a sextant to determine our position, and to teach Ayla how to do it as well (the poor girl). I haven’t been able to spend much time on it, so progress has been slow, but today Ayla and I took our first actual hands-on sights to determine our position, and we had a blast!
To learn how to use a sextant to find our position I’ve read three books on the subject, and I’ve also read the manual that came with the sextant (Davis Mark 25). The first two books were complete treatments of celestial navigation, full of spherical trigonometry and lots of calculations. Let me tell you, these books could cure even the most severe case of insomnia. Although I could follow along with a lot of it, I found myself saying, “This is too hard, and not very fun. I’ve got GPS devices that can tell me where I am, so why am I putting myself through this!?!” But alas, I kept coming back to it.
( David's Voyage )
