The appearance of Gravity

Are you not familiar with the term "ordinary man" when used in regards to observations or judgements, it's quite a common device.

No, actually, I am not. Care to explain what constitutes an 'extraordinary man', since by referring to an ordinary one, you imply the existence of some other kind.

No, actually, I am not. Care to explain what constitutes an 'extraordinary man', since by referring to an ordinary one, you imply the existence of some other kind.

I think in this case it would refer to someone who understands frames of reference. I think it would be fair to say that most people do not. Anyone can take the time to educate themselves on it, they are capable. I would expect that asking 100 people on the street to explain relative frames of reference would result in most of them being very confused.

so, you're saying that gravity works only in specific frames of reference?

A different frame of reference doesn't change a phenomenon anyway, so does it matter?

yes, it does. Because, if gravity changes, it's not a phenomenon according to your own definition.

"ordinary man observations" refers to obeservations without bringing theory/visual aids/extrodrinary circumstances into the equation, it's simply saying forget all those complications, what does it look like.

FET relies quite heavily on the fact that to the "ordinary man" the earth appears to be flat (even though most ordinary men (note the lack of quote marks) think the world is round), this is the essential point behind their "look out of your window/walk around your neighbourhood" argument and is a device they use to try to shift the burder of proof onto RET to a quite unfair degree.

I am simply trying to say that to the "ordinary man" gravity undoubtedly appears to work by things falling towards the ground, not the ground and yourself moving up towards them so if "ordinary man" observations are a guide to truth that places the burden of proof on the UA.

We then get a stalemate in terms of who has the burden of proof which means FET is reuqired to have arguments in favour of it rather than just asking RET to disproove it.

We're in danger of slipping into a semantic debate here (prompted by Parsec). Come on, you guys are better than that. Argue the topic, not the wording.

We're in danger of slipping into a semantic debate here (prompted by Parsec). Come on, you guys are better than that. Argue the topic, not the wording.

Sorry TD but I think that your expectations of this discussion are too high.

yes, it does. Because, if gravity changes, it's not a phenomenon according to your own definition.

The force of gravity, like magnetism, changes depending on the factors playing into it. As I recall from 10th grade earth science, gravity is determined by the masses of the two objects and the distance between them (don't remember the exact formula).

Likewise, magnetism can depend on the strength of the magnet (i.e. what material it is made about, how much power it is being charged with). This is why some magnets are used to lift cars, while others are safe for children to play with. 

Quote from: markjo on December 05, 2009, 11:58:16 AM

Quote from: Tom Bishop on December 05, 2009, 09:44:09 AM

Take a step off the edge of your chair and watch the surface of the earth carefully.

When you walk across the room, are you moving across the floor or is the floor moving under your feet?

When I walk across the floor I'm propelling myself across with my own two legs.

When I walk off the edge of a chair and observe the surface of the earth carefully I'm not propelling myself towards the earth.

Obviously the direct explanation from experience is that the earth is propelling itself towards me.

No. the earth has mass and is attracting you. the only way the earth won't do that, is if you are in the exact centre of a perfectly spherical earth, or infinatly far from it.

the idea that standing on top of a huge mass like the earth, disk or not, and it have no attraction of you downwards violates everything we understand about physics. it is not reality, sorry.

it's like picture you in a spaceship 1000 km from a black hole. You go flying in and are destroyed. was this due to gravity (a force or perhaps warping of spacetime for fans of equivalence etc), or did the black hole feel a huge outside force and whack into you?!? physics says the first idea. you think the second.

your logic to find gravity was found (and mimicked) from observing our logic to show the earth is flat. if you dont even believe our logic, how can you believe a conclusion you have made which is based upon logic you cant dont believe.

you started with a flat earth and ended with a flat earth, so obviously that rules out the gravity thing doesnt it.   

Why does something have to be propelling itself toward something else when you walk off a chair? It makes no sense; it's a false dichotomy. It'd be like if I said "Well, this apple is not purple, and so it must be that the other apple over there is purple."

It's simply Newton's third law. From the point of view of the earth, you are accelerating toward it. From your point of view, the earth is accelerating up toward you. Each force has an opposing force of equal magnitude. And so you are falling toward the center of mass of the earth. And the earth is falling with a negligible acceleration toward you. Looking at the situation from your own inertial frame doesn't somehow alleviate gravity's existence. The physics is the same in every frame of reference.

Hey get back to the WII thing. Nobody has said anything about it!

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What do you mean by "not shot through the Earth"? Do you mean by scientists or by stars?

Yes, scientists.

I didn't say that they would sabotage it. The experiment hasn't happened yet. The experiment will fail because the earth is flat.
[/quote]
I think Tom has still failed to show here any reason why matter in the Sun should be any different than matter in the Earth. His argument about us knowing nothing about the Sun's composition fails because of the neutrino evidence (as well as the EM frequency evidence, but I am not going to argue about that since its not my area). I point anyone who wants to refute this to the Beam Neutrinos or Solar Neutrinos threads. For now I still claim that there is no reason for matter in the Sun to have a gravitational field and not matter on Earth, since current measurements indicate they behave in similar ways.

Hey get back to the WII thing. Nobody has said anything about it!

You want to get back to the Wii thing?  It's a bad example and their Wii/iPhone isn't calibrated properly if it's reading an acceleration of -9.8m/s/s when you drop it.

Quote from: Tom Bishop on December 06, 2009, 04:22:18 PM

Quote from: LiceFarm on December 06, 2009, 04:10:57 PM

Quote from: Tom Bishop on December 05, 2009, 03:47:33 PM

The earth propels itself into us.

How do you know that you aren't propelling down into the earth?

Because when I go into free fall I am inert. I am not propelling myself anywhere.

If your velocity does not change, why do you experience that uncomfortable feeling in your stomache when you start to fall?

This is actually a good argument that I think people here overlooked.  If when I walk off a cliff, and begin to free-fall, why do I get the sensation that I'm accelerating, if it's the Earth that's actually accelerating toward me?

Quote from: Robert64 on December 06, 2009, 04:32:56 PM

Quote from: Tom Bishop on December 06, 2009, 04:22:18 PM

Quote from: LiceFarm on December 06, 2009, 04:10:57 PM

Quote from: Tom Bishop on December 05, 2009, 03:47:33 PM

The earth propels itself into us.

How do you know that you aren't propelling down into the earth?

Because when I go into free fall I am inert. I am not propelling myself anywhere.

If your velocity does not change, why do you experience that uncomfortable feeling in your stomache when you start to fall?

This is actually a good argument that I think people here overlooked.  If when I walk off a cliff, and begin to free-fall, why do I get the sensation that I'm accelerating, if it's the Earth that's actually accelerating toward me?

You don't. You get the feeling of being inert. Your guts are no longer pinned to the earth's surface.

You don't. You get the feeling of being inert. Your guts are no longer pinned to the earth's surface.

LOLWUT?! My guts were never pinned to the earths surface.

And when I do fall I don't get the feeling of being inert. I get the feeling of falling. Aaaaaaaaaaaargh. Like that. Not Wheeeeee this is lovely.

You can perform a simple experiment Tom. Take a chair, stand on it and fall off. Did it feel inert or did you suddenly get panicky and funny in your tummywum?

LOLWUT?! My guts were never pinned to the earths surface.

When you stand on the earth's surface your guts are being pinned to the surface as the earth accelerates your body upwards.

When you go into free fall your guts are free to float around, giving you the feeling you attribute to falling.

Take a gravimeter into free fall sometime. The arrow points to zero acceleration. It's not going anywhere.

Quote

LOLWUT?! My guts were never pinned to the earths surface.

When you stand on the earth's surface your guts are being pinned to the surface as the earth accelerates your body upwards.

When you go into free fall your guts are free to float around, giving you the feeling you attribute to falling.

Take a gravimeter into free fall sometime. The arrow points to zero acceleration. It's not going anywhere.

What is it and what isn't it going anywhere relative to?

Quote from: Tom Bishop on January 27, 2010, 11:26:54 AM

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LOLWUT?! My guts were never pinned to the earths surface.

When you stand on the earth's surface your guts are being pinned to the surface as the earth accelerates your body upwards.

When you go into free fall your guts are free to float around, giving you the feeling you attribute to falling.

Take a gravimeter into free fall sometime. The arrow points to zero acceleration. It's not going anywhere.

What is it and what isn't it going anywhere relative to?

The gravimeter measures acceleration. When you're set it on the floor it reads 9.8 m/s^2, meaning that it is being accelerated by the earth at a rate of 9.8 m/s^2.

When you pick it up and jump off of a plane with it the gravimeter reads 0. The gravimeter is not being accelerated anywhere. It reads 0 acceleration because it is inert.

Quote from: Its a Sphere on January 27, 2010, 12:15:15 PM

Quote from: Tom Bishop on January 27, 2010, 11:26:54 AM

Quote

LOLWUT?! My guts were never pinned to the earths surface.

When you stand on the earth's surface your guts are being pinned to the surface as the earth accelerates your body upwards.

When you go into free fall your guts are free to float around, giving you the feeling you attribute to falling.

Take a gravimeter into free fall sometime. The arrow points to zero acceleration. It's not going anywhere.

What is it and what isn't it going anywhere relative to?

The gravimeter measures acceleration. When you're set it on the floor it reads 9.8 m/s^2, meaning that it is being accelerated by the earth at a rate of 9.8 m/s^2.

When you pick it up and jump off of a plane with it the gravimeter reads 0. The gravimeter is not being accelerated anywhere. It reads 0 acceleration because it is inert.

It measures acceleration RELATIVE TO WHAT!!!??

Stop sputtering, spit out the rest of what it does and quit being obtuse FFS.

It measures acceleration RELATIVE TO WHAT!!!??

Relative to an inertial frame of reference.

Quote from: Its a Sphere on January 27, 2010, 01:40:04 PM

It measures acceleration RELATIVE TO WHAT!!!??

Relative to an inertial frame of reference.

When you take a tape measure and measure something as 24" what is that 24" relative to?

When you take a tape measure and measure something as 24" what is that 24" relative to?

Stop posting and lurk more.

Quote from: Tom Bishop on January 27, 2010, 02:40:31 PM

Quote from: Its a Sphere on January 27, 2010, 01:40:04 PM

It measures acceleration RELATIVE TO WHAT!!!??

Relative to an inertial frame of reference.

When you take a tape measure and measure something as 24" what is that 24" relative to?

IAS, I hate to say it but Tom is correct in the mechanics of how a gravimeter works. It's a type of (and works on the same principle as) an accelerometer. If you have a 4th Generation iPod Nano, iPod Touch, or even an iPhone, you can put them into a diagnostic mode and gain direct access to the accelerometer readings.

However, I wonder if it's the position of the FES that gravity is an illusion, or if it a force that simply doesn't exert itself on Earth?

Quote from: Its a Sphere on January 27, 2010, 02:44:57 PM

Quote from: Tom Bishop on January 27, 2010, 02:40:31 PM

Quote from: Its a Sphere on January 27, 2010, 01:40:04 PM

It measures acceleration RELATIVE TO WHAT!!!??

Relative to an inertial frame of reference.

When you take a tape measure and measure something as 24" what is that 24" relative to?

IAS, I hate to say it but Tom is correct in the mechanics of how a gravimeter works. It's a type of (and works on the same principle as) an accelerometer. If you have a 4th Generation iPod Nano, iPod Touch, or even an iPhone, you can put them into a diagnostic mode and gain direct access to the accelerometer readings.

However, I wonder if it's the position of the FES that gravity is an illusion, or if it a force that simply doesn't exert itself on Earth?

FFS you can lead a horse to water but you can't make him drink.  I was going to try to assist tom in discovering why he was babbling nonsense, but evidently that isn't going to happen.

No Tom isn't correct.  He is trying to use people's ignorance to show that his gravimeter example is proof of anything other than the equivalence principle.

When you measure something as 24" on a tape measure it is relative to a base (usually zero) 24"-0" = 24".

A gravimeter works in the same way.  It measures acceleration relative to a base value.  Guess what that value is? Freefall

When placed on something in contact with the Earth's surface the meter will measure an acceleration relative to it 32.2 ft/s² -0ft/s² = 32.2 ft/s². 
When in "freefall" and the accelerometer will measure 0 ft/s²  guess why? 
Because 0 ft/s² - 0 ft/s² = 0 ft/s²

...Take a gravimeter into free fall sometime. The arrow points to zero acceleration...

Is exactly what would be expected.

It's not going anywhere.

However is misleading..... beceause there is no RELATIVE TO included and his statement proves nothing.

When held fixed in a gravitational field by, for example, applying a ground reaction force or an equivalent upward thrust, the reference frame for an accelerometer (its own casing) accelerates upwards with respect to a free-falling reference frame. The effect of this reference frame acceleration is indistinguishable from any other acceleration experienced by the instrument.

Congratulations on falling for exactly what he wanted you to fall for. 

When you stand on the earth's surface your guts are being pinned to the surface as the earth accelerates your body upwards.

LOLWUT?! My guts were never pinned to the earths surface.

An accelerometer measures zero because all parts of the accelerometer are being accelerated at the same rate.

lrn2tooluse.

Quote from: Tom Bishop on January 27, 2010, 11:26:54 AM

When you stand on the earth's surface your guts are being pinned to the surface as the earth accelerates your body upwards.

Quote from: LiceFarm on January 27, 2010, 03:41:35 AM

LOLWUT?! My guts were never pinned to the earths surface.

An accelerometer measures zero because all parts of the accelerometer are being accelerated at the same rate.

lrn2tooluse.

Actually it masures zero because there is zero acceleration.