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Why physicists are determined to prove Galileo and Einstein wrong

Scientists tested Galileo and Einstein's theories by dropping two objects inside this satellite named MICROSCOPE (artist's impression).
Scientists tested Galileo and Einstein's theories by dropping two objects inside this satellite named MICROSCOPE (artist's impression).
(Image: © CNES)

In the 17th century, famed astronomer and physicist Galileo Galilei is said to have climbed to the top of the Tower of Pisa and dropped two different-sized cannonballs. He was trying to demonstrate his theory — which Albert Einstein later updated and added to his theory of relativity — that objects fall at the same rate regardless of their size.

Now, after spending two years dropping two objects of different mass into a free fall in a satellite, a group of scientists has concluded that Galileo and Einstein were right: The objects fell at a rate that was within two-trillionths of a percent of each other, according to a new study.

This effect has been confirmed time and time again, as has Einstein's theory of relativity — yet scientists still aren't convinced that there isn't some kind of exception somewhere. "Scientists have always had a difficult time actually accepting that nature should behave that way," said senior author Peter Wolf, research director at the French National Center for Scientific Research's Paris Observatory. 

Related: 8 Ways You Can See Einstein's Theory of Relativity in Real Life

That's because there are still inconsistencies in scientists' understanding of the universe. 

"Quantum mechanics and general relativity, which are the two basic theories all of physics is built on today ...are still not unified," Wolf told Live Science. What's more, although scientific theory says the universe is made up mostly of dark matter and dark energy, experiments have failed to detect these mysterious substances.

"So, if we live in a world where there's dark matter around that we can't see, that might have an influence on the motion of [objects]," Wolf said. That influence would be "a very tiny one," but it would be there nonetheless. So, if scientists see test objects fall at different rates, that "might be an indication that we're actually looking at the effect of dark matter," he added.

Wolf and an international group of researchers — including scientists from France's National Center for Space Studies and the European Space Agency — set out to test Einstein and Galileo's foundational idea that no matter where you do an experiment, no matter how you orient it and what velocity you're moving at through space, the objects will fall at the same rate. 

The researchers put two cylindrical objects — one made of titanium and the other platinum — inside each other and loaded them onto a satellite. The orbiting satellite was naturally "falling" because there were no forces acting on it, Wolf said. They suspended the cylinders within an electromagnetic field and dropped the objects for 100 to 200 hours at a time.

From the forces the researchers needed to apply to keep the cylinders in place inside the satellite, the team deduced how the cylinders fell and the rate at which they fell, Wolf said. 

And, sure enough, the team found that the two objects fell at almost exactly the same rate, within two-trillionths of a percent of each other. That suggested Galileo was correct. What's more, they dropped the objects at different times during the two-year experiment and got the same result, suggesting Einstein's theory of relativity was also correct.

Their test was an order of magnitude more sensitive than previous tests. Even so, the researchers have published only 10% of the data from the experiment, and they hope to do further analysis of the rest.

Not satisfied with this mind-boggling level of precision, scientists have put together several new proposals to do similar experiments with two orders of magnitude greater sensitivity, Wolf said. Also, some physicists want to conduct similar experiments at the tiniest scale, with individual atoms of different types, such as rubidium and potassium, he added.

The findings were published Dec. 2 in the journal Physical Review Letters

Originally published on Live Science.

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  • Cab
    Sorry--Galileo was wrong. Heavy objects fall to earth faster than lighter objects even in a perfect vacuum. And Galileo's experiment was theoretically flawed. He dropped two objects--they would fall even faster than each object separately. You smart guys probably understand why. But if you don't, here's a thought experiment: Drop a bowling ball and measure the elapsed time. Now drop the Sun.
    Reply
  • holoman
    Universe gravity field interaction with exotic multi-dimensional entangled Gravity fields influence of Space/Time could be used for space travel in the Galaxies.

    https://drive.google.com/file/d/1f9XdIiJNYFiJGxlOCKOVycn0phO5LTcL/view
    Reply
  • mintaslanxor
    Shouldn't these boffins be engaged in more productive and useful scientific pursuits, such as looking for a practical solution for climate change that doesn't rely on the selfish human nature to do it? If they don't, within a hundred years, all scientific research may become obsolete.
    Reply
  • trainhater
    Challenge everything.
    Reply
  • rajasekaran
    admin said:
    Physicists dropped objects on a satellite for two years to test Galileo's theory of falling objects.

    Why physicists are determined to prove Galileo and Einstein wrong : Read more
    I do have a similar view. In size exclusion chromatography,... Smaller molecules elute last...whether fwo bigger molecules of same size but of different density values, would land in same fraction of elute or not...
    Reply
  • Timmylikesit
    Cab said:
    Sorry--Galileo was wrong. Heavy objects fall to earth faster than lighter objects even in a perfect vacuum. And Galileo's experiment was theoretically flawed. He dropped two objects--they would fall even faster than each object separately. You smart guys probably understand why. But if you don't, here's a thought experiment: Drop a bowling ball and measure the elapsed time. Now drop the Sun.
    Are you out of your mind? Science rhetoric has seriously made your gears smoke from over thinking. You can't drop the the sun on earth. You could drop the earth on the sun. You don't have to be a genius to drop two objects that have differing masses to know that they will both hit the ground at the same time (given that they were actually dropped at the same time.) The earth has a nearly constant gravitational pull making everything fall at the same rate of 9.8 m/s squared. This means that if you take a pound of rock, or 10 pounds of rock they WILL fall at the same rate. If something the size of a planet were to be dropped onto something the size of a star you would be dealing with two differing gravitational pulls. Meaning, objects don't fall at the same rate on earth as they do on the sun. If you dropped a 10lb weight on earth and timed it. It would differ from the same weight dropped on mars because the gravitational pulls differ. And you would have to account for atmospheric drag and other outside forces. Going back to your comment, "even in a perfect vacuum", you cant achieve a perfect vacuum on earth because you can only "vacuum as high as the highest barometric pressure of the the environment. On earth the highest achievable vacuum is equivalent to the highest atmospheric pressure which is around 28.92 inches of mercury. Galileo was more intelligent than us and im sure he would be able to school us on logic any day of the week. But , he didn't know or understand what the people of today would be and i don't blieve was wrong because he didn't factor in a few hundred yeats of new knowledge.
    Reply
  • Heath51
    mintaslanxor said:
    Shouldn't these boffins be engaged in more productive and useful scientific pursuits, such as looking for a practical solution for climate change that doesn't rely on the selfish human nature to do it? If they don't, within a hundred years, all scientific research may become obsolete.

    Your statement shows you have absolutely no idea how the weather works, and totally ignores the fact that the climate has been changing for nearly 4.5 billion years, most of it by far without the help of the "selfish human."
    Get a grip moron!
    Reply
  • Urquiola
    admin said:
    Physicists dropped objects on a satellite for two years to test Galileo's theory of falling objects.

    Why physicists are determined to prove Galileo and Einstein wrong : Read more
    I'd say the Space Station experiment had inherent design drawbacks that make it unconclusive. First, besides gravity, drag acts on the speed an object falls, this may not have been detected by Galileo, but with instruments accurate enough, it will show; about the Space experiment, Platinum and Titanium do have different densities, 21450 kg/m3 vs 4507 kg/m3; weight per volume (Wikipedia), two cylinders of same size will differ in weight, and gravity forces are connected to weight, thus, if the cylinders are of different weight, gravity forces will differ, if same weight, size will differ, drag won't be same, also drag changes with object's shape. Perhaps in absolute empty no drag difference will exist, but: Is there any 'absolute'? The darkest space has some atoms, some photons sparsed, if the time of movement is long enough, drag differences will show. ????
    Reply
  • meofbillions
    mintaslanxor said:
    Shouldn't these boffins be engaged in more productive and useful scientific pursuits, such as looking for a practical solution for climate change that doesn't rely on the selfish human nature to do it? If they don't, within a hundred years, all scientific research may become obsolete.
    Boffins. I never heard that before. Thanks. It sounds disrespectful, but it's not. Anyway, no. Not those particular people. It's like asking a butcher if he shouldn't be doing carpentry because you think carpentry is more useful to humanity than supplying meat for meat eaters.
    Reply
  • TorbjornLarsson
    Cab said:
    Sorry--Galileo was wrong. Heavy objects fall to earth faster than lighter objects even in a perfect vacuum. And Galileo's experiment was theoretically flawed. He dropped two objects--they would fall even faster than each object separately. You smart guys probably understand why. But if you don't, here's a thought experiment: Drop a bowling ball and measure the elapsed time. Now drop the Sun.

    Galileo has been right this far - see the article - and that has nothing to do with intelligence but observation - see the article. By the way, Sun and other stars are "dropped" all the time as they move in space, moving accordingly to general relativity as far as we can tell.
    Reply