Science Debunks Common Myths: The Persistent Belief in Misleading Theories
In the realm of science, there are many theories, misconceptions, and hypotheses that have been explored, challenged, and sometimes debunked. But despite the overwhelming evidence, some of these theories continue to persist, believed by many due to past publications or lack of awareness of updated research. Two prominent examples are the retraction of a controversial study regarding the MMR vaccine and the ongoing use of Newtonian physics in everyday applications.
MMR Vaccine and Autism: A Case of Retracted Misinformation
Twelve years after a groundbreaking study in The Lancet linked the measles, mumps, and rubella (MMR) vaccine to autism, the paper has been retracted. This move was made after flawed research and statistical errors were discovered. Despite the retraction, the belief in this connection persists among many individuals, highlighting the difficulty in changing deeply ingrained beliefs based on a single piece of controversial research.
Newtonian Physics: Simplicity Wins Over Relativistic Precision
Einstein's revolutionary theories have shown that Newtonian physics, though elegant, are not always accurate, especially in scenarios involving very high velocities. For instance, Newton's formula for momentum, ( p mv ), where ( m ) is mass and ( v ) is velocity, is not strictly correct in contexts involving near-light-speed velocities.
The more accurate formula is:
[ p frac{mv}{sqrt{1 - frac{v^2}{c^2}}}]
where ( c ) is the speed of light in a vacuum. While the difference between Newton’s formula and the corrected one is negligible for most everyday applications, the precision required in fields like astronautics necessitates using the corrected formula.
The Practical Relevance of Relativistic Physics
Even with the refined formula, the difference between the two is often so small that it is dwarfed by the limitations of measurement technology. Consider a scenario where you're measuring the momentum of a modern fighter jet. The speed of light in a vacuum is approximately 300,000,000 meters per second. For a jet cruising at just under the speed of sound (300 meters per second), the difference in momentum calculations is practically negligible.
Let's break it down with actual numbers:
For a McDonnell-Douglas F-15C at maximum takeoff weight (30844 kg) cruising at 300 meters per second:
Newtonian formula calculation: ( p 300 times 30844 9,253,200 ) kgm/s Relativistic formula calculation: ( p frac{300 times 30844}{sqrt{1 - left(frac{300^2}{300,000,000^2}right)}} approx 9,253,200.000004627 ) kgm/sThe discrepancy is approximately 15 micrograms, or about the mass of a square of printer paper. This small discrepancy is so insignificant that it vanishes in the uncertainty of measurement tools. For most practical applications, Newtonian physics works just fine.
Why We Still Use Newtonian Physics
Despite the existence of more precise formulas, Newton's formulations are simpler and easier to apply, especially in daily life. The precision of Newtonian physics is more than sufficient for most applications, and the minor errors are insignificant compared to measurement limitations. This practical utility makes Newtonian physics the default choice in many scenarios.
Conclusion
While modern science has provided us with more accurate models, many older theories continue to be believed due to their historical significance or the difficulty in changing ingrained beliefs. However, it's crucial to understand and use the most accurate models available for precise and complex applications, such as those in space exploration or cutting-edge physics experiments.