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Author Topic: there is no such thing as gravity  (Read 3401 times)

Offline gazza711

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there is no such thing as gravity
« on: 25/03/2014 21:44:00 »
hi.we know that gravity is only a theory,so it doesn't exist then.I have a new theory that a kid could understand and want to share it with the world in the right way,and I could prove it too.its nothing to do with magnetism between objects or any theory ever documented.this will enable the theory of a hoverboard I believe!!!

Some non-physist in...


 

Offline alancalverd

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Re: there is no such thing as gravity
« Reply #1 on: 25/03/2014 23:38:45 »
A theory is not worth the paper it is printed on, unless it explains something that was previously not understood, or predicts something that is subsequently demonstrated.

So please first show us the hoverboard, then explain it.
 

Offline gazza711

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Re: there is no such thing as gravity
« Reply #2 on: 26/03/2014 20:20:15 »
well the hoverboard is in the making.but I yet to ask what the best explanation of gravity is.everyone says that it is the same thing that causes all masses to attract.my problem is if I have the only answer,how should I go about disclosing this as its more obvious than quantum stuff.
 
 

Offline Pmb

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Re: there is no such thing as gravity
« Reply #3 on: 30/03/2014 06:01:41 »
Quote from: gazza711
hi.we know that gravity is only a theory,so it doesn't exist then.
That's quite incorrect! When someone makes a statement like that it's a clear sign that they've never learned what the term "Theory" means as it's used in all branches of science.

Before you continue along this line of reasoning I suggest that you you read the following as it applies to this context, i.e. to the "theory" of gravity. See

http://www.merriam-webster.com/dictionary/theory
Quote
a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena <the wave theory of light>

Then read this http://home.comcast.net/~peter.m.brown/ref/philosophy_physics.pdf

Gravity is simple the name that we give to the phenomena whereby bodies interact with each other, e.g. as when a stone, when not supported about the earth's surface and is initially at rest, will fall. A moon orbits a planet is due to the moon being attracted to the planet, etc. We give the name "gravity" to this phenomena. To say that gravity doesn't exist is like saying that objects don't fall when dropped, people don't have weight, etc. Claiming that it doesn't exist because you thought that nobody proved it does is a very very poor argument. There's absolutely no valid logic to it. And that's how you're arguing it about.

Quote from: gazza711
I have a new theory that a kid could understand and want to share it with the world in the right way,and I could prove it too.its nothing to do with magnetism between objects or any theory ever documented.this will enable the theory of a hoverboard I believe!!!
Some non-physist in...
Nothing personal but if you use the same logic in your new theory as you used in the old one then
I can promise you that your new theory will be wrong.
« Last Edit: 31/03/2014 05:23:32 by Pmb »
 

Offline gazza711

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Re: there is no such thing as gravity
« Reply #4 on: 03/04/2014 22:08:55 »
Hi there and thanks for the replies.I am a newbie to scientific forums.

I stand corrected as my statement was incorrect.

gravity in space applies to the orbits and satellites in general.

My statement is now that,gravity in space and us being pulled to the earth are not the same thing.I have figured out the answer to many of my own questions,but cant explain why bigger masses attract smaller.im sure I will know soon.

maybe if I changed my theory to 'we are being pushed down and not pulled down'.

is this a more suitable statement?
 

Offline Pmb

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Re: there is no such thing as gravity
« Reply #5 on: 04/04/2014 23:11:36 »
Quote from: gazza711
Hi there and thanks for the replies.I am a newbie to scientific forums.
Howdy, and welcome to the forum. And you're welcome.

Quote from: gazza711
I stand corrected as my statement was incorrect.
You made a lot of statements. Which ones do you now recognize as being wrong?

Quote from: gazza711

gravity in space applies to the orbits and satellites in general.
What do you mean by in space. I don't know you and therefore I don't know anything about you so let me ask a few questions to get things going.

Typically people use the word "space" they are referring to the places outside the earth's atmosphere. A satellite orbiting the earth from 500 miles from the center of the earth is moving in a region where the atmosphere is so thin as to be zero for most practical purposes. People refer to this as "being in space." Space also refers to something which is difficult to define. Wikipedia takes a crack at it here - http://en.wikipedia.org/wiki/Space
Quote
Space is the boundless three-dimensional extent in which objects and events have relative position and direction.[

Quote from: gazza711

My statement is now that,gravity in space and us being pulled to the earth are not the same thing.
What exactly is your educational background? Have you ever studied physics or Newton's theory of gravity? Do you know what physicists are referring to when they define and use the term gravity?

Quote from: gazza711
I have figured out the answer to many of my own questions, ...
Which questions of yours are you referring to and what was your answer to them?

Quote from: gazza711

...but cant explain why bigger masses attract smaller.im sure I will know soon.
You've got it wrong. A larger body doesn't simply exert a force on the smaller body. The smaller body also exerts a force on the larger body. This is the kind of thing Newton referred to as his third law "Wherever there is an action there is always an equal and opposite reaction."

The force body #1 body exerts on another body #2 is has the exact same value as the force that body #2 exerts on body #1. The equation which expresses this is

F_12 = Force body 1 exerts on body 2 = GMm/r^2

where M = body #1 and m = body #2. Newton's third law is expressed as ]

F_21 = Force body 2 exerts on body 1 = GMm/r^2

Force is a vector quantity and therefore has a direction to it. In Newtonian mechanics these forces point in opposite directions. The force on body 2 due to body one is directed along a line from body 2 to body 1 and vice versa.

You can see from all of this why a larger body exerts a force on a smaller body. What you didn't know is the smaller body also exerts a force of the same magnitude on the larger body.

Quote from: gazza711

maybe if I changed my theory to 'we are being pushed down and not pulled down'.
Why? Pushing and pulling has no meaning when you're referring to the force of gravity. It only applies to what are referred to as "contact forces" which gravity is not one. What led you to such an idea?

Quote from: gazza711

...is this a more suitable statement?
No. Very far from it in fact. To "push" something means that you apply a force to the surface of an object and direct the force in the direction which points into the body. Therefore when you're pushing something you're increasing the stress inside the body. One example of something being pushed is a car. Go to the back of a car which is in neutral. Apply a force to the surface of the rear bumper in the direction pointing from rear to front.

To "pull" something means that you're once again applying a force to the surface of an object but now you're applying they force in a direction away from the interior of the body. Therefore when you're pulling something you're increasing the tension inside the body. Applying a contact force to a body and directing the force outwards is like tying a rope to a car's bumper and pulling on the rope.

Gravity doesn't work this way since it's not a contact force and only when tidal forces are present can gravity induce either stress or tension inside a body. If you place a body in a uniform gravitational field the force of gravity acts on every single point inside the body. A uniform gravitational field cannot induce stresses or tension in any body and therefore pulling or pushing makes no sense at all in this case. In fact it makes no sense when the field isn't uniform either.

Do you now understand the difference between push and pull and what they mean and how they're defined in the context of physics?
 

Offline gazza711

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Re: there is no such thing as gravity
« Reply #6 on: 05/04/2014 18:04:22 »
hi.i am a chef.only gsce in physics and chemistry.lol.i understand push and pull now.
My statement indicates that gravity on earth pulls us down.gravity outside earths atmosphere influences the orbits,satelites etc.this I understand this to be newtons theory and I expect it has been solidly proven by now with all the money and technology we have nowdays.

So as I said,on earth it is said that the gravity on earth makes objects fall to the ground,keeps satelites in orbit and keeps the moon in orbit as well.

gravity on earth in newtons law is the same thing that keeps the planets orbiting the sun etc.saturns rings and jupiters moons etc.

My statement says that nothing pulls us down to the ground on earth,and that same thing is not what keeps our satelites in orbit.

when we are so called attracted to the earths surface I agree we are not being pulled or pushed.when a balloon is inflated with helium,is it pushed or pulled up?

when I say that gravity does not exist,i mean the explanation of gravity I believe is not true.most people would assume it is some magnetic attraction of some sort.yes gravity is the phenomena that causes bodies to attract.totally agree and learning how to word things a bit better now.

So,what keeps everything we see on the ground.this is the big question now?oh and I wouldn't say all things on earth are attracted to earth-which means I am saying that all gravity on earth as we know it doesn't exist because we are not being attracted in any way.when you say that gravity is the phenomena that attracts,then we don't experience gravity on earth and possibly in the solar system.

I know I am being annoying,but I am trying to educate myself here.lol
 

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Re: there is no such thing as gravity
« Reply #6 on: 05/04/2014 18:04:22 »

 

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