Gravity isn't real

[Muse]

Gravity is more real than Moonbogg, who's out of sight out of mind. Gravity, if you ignore it will come back and smack you in the ass.

 

[Newell Steamer]

Gravity is SO real that it even comes from things we can't even see.

 

[smackababy]

I remember exactly what I was doing the day/moment I realized that God was made up by people, no more real that Spiderman, a shaggy dog story to keep you befuddled. I was looking out my window, maybe about 11 years old.

Honestly, I think that William Blake, if you told him that Gravity wasn't real would tell you you're being an ass. He might not care for your quantifying it like Newton did, but he'd say you are calling a dog a cat.

Are you trying to imply Spiderman isn't real? Boo this man!

 

[moonbogg]

If you can measure it, it is real.

We can measure gravity. It is therefore real.

The gospel according to moonbogg. Once he gets around to quoting me on it.

Oh, its you. Explain yourself.

 

[Muse]

Are you trying to imply Spiderman isn't real? Boo this man!

Well, I bought Spiderman 1 and Spiderman 2 DVD's, liked them. I should rewatch them.

 

[Paratus]

Well, I bought Spiderman 1 and Spiderman 2 DVD's, liked them. I should rewatch them.

 

[disappoint]

If you can measure it, it is real.

We can measure gravity. It is therefore real.

The gospel according to moonbogg. Once he gets around to quoting me on it.

Oh, its you. Explain yourself.

haha I like the "Oh, it's you."

Gospels require no explanation, they are just to be believed because someone said so.

 

[disappoint]

Just kidding about the gospel spiel. You have to admit though moonbogg, you've been on a "this is so because I say so" crusade as of late. So I was poking a little fun at that. Here's a nice article on the science behind what I meant by "we can measure gravity":

...The usual lab set-up is to take two macroscopic objects with known masses, such as two spheres of metal, and to measure the attractive pull between them using a specially designed and highly precise balance. In the latest experiment, reported in Nature, physicists calculated Big G by measuring the gravitational attraction between individual atoms of the element rubidium. “Our measurement of G was performed, for the first time, using a microscopic probe rather than macroscopic objects,” says Guglielmo Tino of the University of Florence, who led the research.

In Tino’s sophisticated experiment, his group first isolated and cooled a collection of rubidium atoms to just a few degrees above absolute zero.

Then, from below, they pointed a laser beam at the cold atoms to launch them up a tube. As the fountain of atoms rose and then fell, the group used heavy blocks of metal placed around the tube to alter the atoms’ speeds. By recording how the metal blocks, by virtue of their gravity, affected the atoms’ velocities Tino’s group could calculate Big G.
The resulting set-up was so sensitive, says Tino, it had to be operated by remote control otherwise the measurement could be skewed by the gravitational attraction of the scientists in the room.

The experiment is quite a feat, says Stephan Schlamminger of the National Institute of Standards and Technology in the US. “I find it totally amazing that you can measure gravity, which is a macroscopic force, with a tiny little rubidium atom,” he says.

According to Tino’s experiment, Big G is 6.67191 x 10-11 m3 kg-1 s-2. But as Tino’s results vary from the official value of 6.67384 x 10-11 m3 kg-1 s-2 they don’t resolve the problem. The rubidium experimental result is an outlier – but so are almost all the Big G measurements made over the last 20 years. It remains one of the mysteries of experimental physics.
The disagreement between measurements of Big G has prompted some physicists to propose radical explanations whereby the gravitational constant is not so constant. Some suggest it could fluctuate from day to day, or over short distances, such as the few centimetres separating objects in the lab.

For Quinn and most other physicists, however, the likely explanation is much simpler: it is tied to the actual experiments and to measuring something so weak. Somehow we are making systematic errors we don't know about, he thinks. “But these experiments are so subtle, it's very difficult to see what the error would be.”

To address the problem, Quinn recently arranged a meeting of the Royal Society in the UK entitled “The Newtonian Constant of Gravitation, a Constant Too Difficult to Measure?” The attendees, including Tino and Schlamminger, agreed to collaborate to perform a single measurement in a way that uses everybody’s experience. They will meet again in the US in October to start planning the details of the joint measurement.

Big G is hugely important for cosmology and for modelling the Universe, but it doesn’t have any practical benefits here on Earth. Not knowing Big G with perfect precision didn’t stop us putting a man on the Moon, or from plotting the paths of satellites, Schlamminger says. He also notes that the lack of an economic driver is slowing down research: “You can't make money out of a precise knowledge of the gravitational constant.”
Big G is the Mount Everest of metrology (the study of measurement) – it is the supreme difficulty of the challenge that makes the pursuit itself worthwhile, Schlamminger says. For Quinn too, the main reason to measure Big G is because we currently cannot. “It's an area of experimental physics that we can't get right and we need to know why,” he says. “That's an important reason to pursue this.”

https://cosmosmagazine.com/physical-sciences/measuring-gravity-have-we-finally-cracked-it

 

[Paratus]

Just kidding about the gospel spiel. You have to admit though moonbogg, you've been on a "this is so because I say so" crusade as of late. So I was poking a little fun at that. Here's a nice article on the science behind what I meant by "we can measure gravity":

Very cool experiment. :thumbsup:

 

[DrPizza]

Just kidding about the gospel spiel. You have to admit though moonbogg, you've been on a "this is so because I say so" crusade as of late. So I was poking a little fun at that. Here's a nice article on the science behind what I meant by "we can measure gravity":

Perhaps you need to read the last paragraph again though.

 

[Squisher]

I have taken (and aced) college physics classes and have never been satisfied by the explanations of how a gyroscope works. For every force vector doing stuff on one side of gyroscope there are force vectors on the other side that should nullify them.

 

[disappoint]

Perhaps you need to read the last paragraph again though.

Well the author of the article says we cannot. So I disagree. It's been measured. Just because all the measurements don't agree to a very high degree of precision doesn't mean it hasn't been measured. We are not done measuring it to be sure of it's precise magnitude, but it is measurable IMHO.

 

[Paratus]

Here's another cool gravitational experiment that supports Einsteins theory of relativity, specifically frame dragging.

http://physics.aps.org/articles/v4/43

According to Einstein’s theory, space and time are not the immutable, rigid structures of Newton’s universe, but are united as spacetime, and together they are malleable, almost rubbery. A massive body warps spacetime, the way a bowling ball warps the surface of a trampoline. A rotating body drags spacetime a tiny bit around with it, the way a mixer blade drags a thick batter around.

The spinning Earth does both of these things and this is what the four gyroscopes aboard the earth-orbiting satellite Gravity Probe B measured. The satellite follows a polar orbit with an altitude of 640 kilometers above the earth’s surface (Fig. 1, top). The warping of spacetime exerts a torque on the gyroscope so that its axis slowly precesses—by about 6.6 arcseconds (or 1.8 thousandths of a degree) per year—in the plane of the satellite’s orbit. (To picture this precession, or “geodetic effect,” imagine a stick moving parallel to its length on a closed path along the curved surface of the Earth, returning to its origin pointing in a slightly different direction than when it started.) The rotation of the Earth also exerts a “frame-dragging” effect on the gyro. In this case, the precession is perpendicular to the orbital plane and advances by 40 milliarcseconds per year. Josef Lense and Hans Thirring first pointed out the existence of the frame-dragging phenomenon in 1918, but it was not until the 1960s that George Pugh in the Defense Department and Leonard Schiff at Stanford independently pursued the idea of measuring it with gyroscopes.

The Gravity Probe B (or GP-B, in NASA parlance) gyroscopes (Fig. 2) are coated with superconducting niobium, such that when they spin, the supercurrents in the niobium produce a magnetic moment parallel to the spin axis. Extremely sensitive magnetometers (superconducting quantum interference detectors, or “SQUIDs&#8221 attached to the gyroscope housing are capable of detecting even minute changes in the orientation of the gyros’ magnetic moments and hence the precession in their rotation predicted by general relativity..........

The rotors required to measure the effects were the most perfectly round objects ever created at the time.

 

[disappoint]

I have taken (and aced) college physics classes and have never been satisfied by the explanations of how a gyroscope works. For every force vector doing stuff on one side of gyroscope there are force vectors on the other side that should nullify them.

You say precession, I say precision....let's call the whole thing off...

 

[disappoint]

Very cool experiment. :thumbsup:

Thanks.

Here's another cool gravitational experiment that supports Einsteins theory of relativity, specifically frame dragging.

http://physics.aps.org/articles/v4/43


The rotors required to measure the effects were the most perfectly round objects ever created at the time.

Likewise, very cool experiment as well.:thumbsup: Thanks for posting the article.

 

[moonbogg]

The measurements are fine and work within a narrow view, but I claim that no one knows what it is that they are measuring. This the same as studying a light switch. It goes one way, the light goes on. This measurement can be studied to a certain degree of precision, but what good is it really if they don't know why the light goes on?
You call it gravity, that's fine. At least admit that it's a placeholder term for something perfectly unknown.

 

[SparkyJJO]

Posting in a troll thread as you cannot be serious. Or you're on drugs. Or drunk. Maybe both :hmm:

 

[ringtail]

then please explain WHY
her (formerly pretty, perky) boobs fell
over past few years

Pieces of gravity stealthily lurk all around us, dang

 

[FallenHero]

It's nice to see the drug culture is alive and well.

 

[Maximilian]

Really, its not. Its apparent effects are real of course, but gravity isn't understood. Nothing is fully understood until the most basic levels of reality are understood. From there we can reconstruct the world back to what we observe. For now, gravity is bullshit.

When I first learned that it surprised me, I kind of stammered in my mind "b but Issac Newton... etc??" I never realized gravity is a phenomenon that isn't understood at all. Kinda shocking.

 

[z1ggy]

The measurements are fine and work within a narrow view, but I claim that no one knows what it is that they are measuring. This the same as studying a light switch. It goes one way, the light goes on. This measurement can be studied to a certain degree of precision, but what good is it really if they don't know why the light goes on?
You call it gravity, that's fine. At least admit that it's a placeholder term for something perfectly unknown.

Why are you so hung up??

Nobody understands magnetism really, and why it is the way it is. But we have mathematical formulas that describe the fields extremely accurately (just like gravity), so for now, that is the best we have.

I don't think anybody here will argue with you that it's cause is unknown. But going back to your original point and title of this thread... That does NOT make gravity "BS". It's simple not understood in its entirety.

 

[JulesMaximus]

You say precession, I say precision....let's call the whole thing off...

We should write a musical. Let's collaborate. :awe:

 

[ImpulsE69]

Tie some 50lb weights to your balls for 24 hours then come back and tell us the results.

If it isn't gravity, maybe it's Satan and he just really hates your balls.

 

[Ruptga]

The measurements are fine and work within a narrow view, but I claim that no one knows what it is that they are measuring. [citation needed] This the same as studying a light switch. [citation needed] It goes one way, the light goes on. This measurement can be studied to a certain degree of precision, but what good is it really if they don't know why the light goes on? [begging the question] [argument from O'Reilly]
You call it gravity, that's fine. At least admit that it's a placeholder term for something perfectly unknown. [begging the question]

 

[rudder]

gravity does not pull us to the surface of the earth. Space is pushing us down. had an interesting conversation with Albert Einstein while I was tripping.