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15 Mei 2016

TIME DILATION BY AIR DENSITY, NOT GRAVITY


: DOUBLE-CHECK OF HAFELE-KEATING EXPERIMENT 1971


Clocks at higher altitude tick faster than clocks on Earth's surface. It is not caused by gravity, but by air density of atmosphere. Closer to the earth surface, the air is denser compared to the density of the air layer above it. The density is getting looser or weaker when it is getting higher.
Tentu saja, pesawatnya juga bergerak lebih cepat!


The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variation).

By volume, dry air contains 78.09% nitrogen, 20.95% oxygen,0.93% argon, 0.039% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere. Air content and atmospheric pressure vary at different layers, and air suitable for use in photosynthesis by terrestrial plants and breathing of terrestrial animals is found only in Earth's troposphere and in artificial atmospheres.

The atmosphere has a mass of about 5.15×1018 kg, three quarters of which is within about 11 km (6.8 mi; 36,000 ft) of the surface. The atmosphere becomes thinner and thinner with increasing altitude, with no definite boundary between the atmosphere and outer space. The Kármán line, at 100 km (62 mi), or 1.57% of Earth's radius, is often used as the border between the atmosphere and outer space. Atmospheric effects become noticeable during atmospheric reentry of spacecraft at an altitude of around 120 km (75 mi). Several layers can be distinguished in the atmosphere, based on characteristics such as temperature and composition.


(wikipedia.org)



Hafele-Keating Experiment in 1971


Hafele and Keating aboard a commercial airliner, 
with two of the atomic clocks and a stewardess.


The Hafele–Keating experiment was a test of the theory of relativity. In October 1971, Joseph C. Hafele, a physicist, and Richard E. Keating, an astronomer, took four cesium-beam atomic clocks aboard commercial airliners. They flew twice around the world, first eastward, then westward, and compared the clocks against others that remained at the United States Naval Observatory. When reunited, the three sets of clocks were found to disagree with one another, and their differences were consistent with the predictions of special and general relativity.

General relativity predicts an additional effect, in which an increase in gravitational potential due to altitude speeds the clocks up. That is, clocks at higher altitude tick faster than clocks on Earth's surface. This effect has been confirmed in many tests of general relativity, such as the Pound–Rebka experiment and Gravity Probe A. In the Hafele–Keating experiment, there was a slight increase in gravitational potential due to altitude that tended to speed the clocks back up. Since the aircraft flew at roughly the same altitude in both directions, this effect was approximately the same for the two planes, but nevertheless it caused a difference in comparison to the clocks on the ground.

Results

(wikipedia.Hafele-Keating)




Clocks at higher altitude tick faster than clocks on Earth's surface. It is not caused by gravity, but by air density of atmosphere. Closer to the earth surface, the air is denser compared to the density of the air layer above it. The density is getting looser or weaker when it is getting higher.

It is has been known in traveling on an airplane. At higher altitude the density of amosphere is getting looser or weaker, and less of friction on an airplane.  Traveling in weaker density of atmosphere an airplane can move faster than in denser atmosphere.








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