The Sagnac effect occurs to a pair of light beams traveling in a circuit in the opposite direction. If the circuit itself is rotating, then the beams will complete the circuit in different duration. The effect was first demonstrated by Georges Sagnac in 1913.
After discovering this effect, Sagnac incorrectly used the results as proof of the aether’s existence, and today’s flat-Earthers use it as “evidence” of stationary Earth. In reality, Sagnac was not aware that the effect is consistent with Einstein’s theory of relativity. And if the effect really proved aether, then optical gyroscopes are impossible.
The Sagnac effect is used as the basis of optical gyroscopes, including fiber-optic gyroscopes and ring-laser gyroscopes. In an optical gyroscope, a pair of light beams are made to travel in a circuit in the opposite direction. Because light travels at a constant speed, irrespective of the transmitter’s speed, then if the gyroscope is rotated, a beam of light will complete the circuit sooner than the other. From the difference, we can measure the rotating motion of the gyroscope.
In a StarTalk episode, Neil deGrasse Tyson was given the question “what is gravity?” He quipped “we have no idea” before elaborating more. Flat-Earthers quoted it out of context to discredit Neil and gravity, completely disregarding what Neil explained afterward.
In reality, Neil did provide a very comprehensive answer to the question “what is gravity” but flat-Earthers only gave an emphasis to the “we have no idea” part of his answer, and skipped the rest of his answer.
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Airy’s Failure was an experiment performed in 1871 in which Sir George Biddell Airy failed to confirm the aether theory by measuring stellar aberration. The phenomenon of stellar aberration, in itself, was the first direct evidence of Earth’s motion around the sun.
Flat-Earthers claim that the “failure” in “Airy’s Failure” is the failure of proving the motion of Earth. In reality, the experiment aimed to confirm the aether theory. The “failure” was in proving the aether theory. The experiment relied on the already accepted knowledge that Earth is in orbit around the sun.
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A fictitious force is a force that appears to act on every object when the frame of reference is accelerating. The term “fictitious” does not mean the force does not exist, but it is not an actual force that arises from an interaction between objects.
Flat-Earthers noticed gravity is considered a fictitious force and use the fact to “prove” gravity does not exist. In reality, we can feel a fictitious force. It is merely a term we use for forces that arise due to an accelerating frame of reference.
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Albert Einstein used thought experiments as a tool for formulating his theories. His theories provided predictions that can be tested in observation and experiments. He did not perform the observation and experiments himself. Others did and confirmed his theories.
Some flat-Earthers dismiss Einstein’s theories —especially those about gravity— on the basis that they are founded on thought experiments and daydreaming. They are wrong. His theories have been repeatedly confirmed by various experiments and observation performed by many others, even to this day.
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Gravity is a natural phenomenon by which all things with mass or energy are brought toward one another. Today, the phenomenon of gravity is explained by two theories: Newton’s law of universal gravitation and Einstein’s general relativity.
Flat-Earthers take the existence of the two explanations as inconsistency in science and use it as a “proof” of deliberate misconduct. Such allegation is obviously only a result of their prejudice. The two theories are the correct explanations of gravity, and can reliably predict the outcome of the phenomenon.
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Classical physics —like Newton’s law of motion, and Newton’s law of universal gravitation— has been superseded by Special Relativity, General Relativity, and Quantum Mechanics. But it doesn’t mean classical physics is wrong. Classical physics is still applicable when the parameters approach common, terrestrial values we use every day.
Pseudoscientists —including flat-Earthers— often misunderstood this and take the fact that classical physics is still being taught in schools as ‘proof’ of deception and the failure of modern science to explain the world. They are wrong.
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Some flat-Earthers mentioned the fact that graviton —the mediating particle of gravitation— is ‘not yet observed’. They took this fact as ‘proof’ that gravity does not exist.
Often they would triumphantly show us screenshots of the table of fundamental particles they took from Wikipedia and other sources. In the ‘gravitation’ column, they would point out its mediating particle has not been observed yet. And they would conclude that scientists are aware gravity does not exist, and we all have been lied to.
Obviously, they are wrong on all accounts.
Continue reading “The Hypothesized Graviton and Flat-Earthers’ Zeal to Disprove Gravity”
Flat-Earthers quoted Einstein’s statement out of context to give the appearance that he gave credence to the notion that Earth is stationary. In reality, Einstein never said the Earth is stationary.
The quote came from his Kyoto address “How I created the theory of relativity,” December 14, 1922.
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Things fall down because of gravity. The mass of the Earth causes everything to fall down at 9.8 m/s² near the surface of the Earth. This constant is called ‘gravitational acceleration’ and usually denoted by ‘g’.
Most flat-Earthers deny the existence of gravity. According to them, things fall down because of density or buoyancy, not gravity. They are wrong.
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Aether was the hypothetical material that fills the region of space. It was assumed to be the medium that allows light and gravity to propagate in space. Throughout the late 1800s and early 1900s, some experiments were carried out to prove if the aether exists.
Flat-Earthers (and geocentrists alike) often use the results of these experiments to support their case that the Earth is stationary. But they are wrong. These experiments were conducted to prove if the Aether theory, or if one of its competing hypotheses —like the Special Relativity— better explains reality.
Continue reading “The Aether Experiments are Never Evidence of Flat and Stationary Earth”