Beleth
FAQ Creator
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- Dec 10, 2002
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Okay, let's do this the rigorous way.Question said:
1. Work out test process.
2. Determine an objective success criterion.
3. Perform test process.
4. Determine whether the criterion in step 2 was met.
Here is my proposed test process.
- I will pick up the pen on my desk with my left hand.
- I will stand up and hold my left arm straight out to my side, parallel to the ground, with the pen still in my hand, so that there is no solid object (including my hand) between the pen and the ground.
- I will then let go of the pen.
My proposed success criterion is that the pen will accelerate downward, in the direction of my feet, and continue to accelerate until the ground intervenes and stops its movement, 8 tries out of 10.
If that test process and success criterion are acceptable to you, please say so. If not, then the burden of modifying the test process and success criterion falls on both of us, and you will need to advise me on how they can be changed to become acceptable to you.
Re: Re: Gravity does not exist
Couldn't a downward acceleration be caused by air currents?
Couldn't an initial downward velocity cause a downward movement?
How do you intend to measure the acceleration?
Beleth said:
Couldn't a downward acceleration be caused by air currents?
Couldn't an initial downward velocity cause a downward movement?
How do you intend to measure the acceleration?
Not feeling so confident in the so-called laws of physics after all, eh!
Re: Re: Re: Re: Re: Re: Re: Gravity does not exist
And there are still electro-magnetic forces that hold the molecules in your floor together. What potential you butt has, has little to do with that, except your butt is also hold together by electro-magnetic forces between the proteins which build up your body.
Hey.....I'm not little! I'm 180 cm long! And hardly a boy, although I hade a date with a 24 year old yesterday.Question said:
And there are still electro-magnetic forces that hold the molecules in your floor together. What potential you butt has, has little to do with that, except your butt is also hold together by electro-magnetic forces between the proteins which build up your body.
Question, whoever the hell you are, go take a freshman physics class.
Tens of thousands of teenagers do it every year and manage just fine. Of course, all of them are smarter and more mature than you are, but you never know, you might surprise us.
Tens of thousands of teenagers do it every year and manage just fine. Of course, all of them are smarter and more mature than you are, but you never know, you might surprise us.
Upchurch said:
The mighty Jim Hartle has written a new introductory college-level book to gravity that's supposed to be very good as it's more physical and less mathematical. And if he doesn't know gravity, no-one does.
And this thread has just reminded me to order the book...
wipeout said:The mighty Jim Hartle has written a new introductory college-level book to gravity that's supposed to be very good as it's more physical and less mathematical. And if he doesn't know gravity, no-one does.
And this thread has just reminded me to order the book...
Misner, Thorne and Wheeler are people I've heard of. Who the heck is Hartle?
Re: Re: Re: Re: Re: Re: Re: Re: Re: Gravity does not exist
OK, lets see. If there where no floor where you are, you would fall down, right? Pulled by gravity. But, there are materials in the way, these materials are hold tighter by electro-magnetic forces, in the shape of covalent binding, London forces, hydrogen binding, etc. These electro-magnetic forces are strong enough to keep you from falling through your floor. That means that the electro-magnetic force is much much stronger than gravity. If gravity was as strong as the electro-magnetic force, we would have great problems, I tell you!!Question said:
wipeout said:He's the Hartle of "Hartle and Hawking's wavefunction of the universe" amongst other things. I assume you've heard of the Hawking.
Okay, so he's working on quantum cosmology. What was the connection with Hawking? Just them both doing work in the field, or something specific? I didn't find any papers co-authored, but that was just a quick search, and doesn't rule anything out. I see some papers with Gell-Mann. I know the phrase "wavefunction of the universe" came from Everett.
Beleth
FAQ Creator
- Joined
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- 4,125
Re: Re: Re: Gravity does not exist
No, an initial downward velocity would not cause a downward acceleration. That's why I worded it to measure acceleration instead of velocity. As gravity is supposed to exhibit the characteristics of a force, its effect on a mass (the pen) will in theory cause the pen to accelerate.
Let's make sure we agree on the protocol before we discuss measurement methods.
A downward acceleration caused by air currents would be detectable by other means. How do you propose we eliminate the possibility of an air current causing the downward acceleration?Question said:
No, an initial downward velocity would not cause a downward acceleration. That's why I worded it to measure acceleration instead of velocity. As gravity is supposed to exhibit the characteristics of a force, its effect on a mass (the pen) will in theory cause the pen to accelerate.
Let's make sure we agree on the protocol before we discuss measurement methods.
My confidence has nothing to do with it. If you require more conclusive results, specify them.
Upchurch
Papa Funkosophy
If you are truly interested in understanding how gravity works, there is nothing finer than their book on the subject, imho. (a brief warning, it is written in two languages, both English and math.)Question said:
Question said:
Hawking and Hartle's collaborations are quite well-known, only 4 papers in all I think but highly influential. They are from 20 to 35 years ago or so.
Hartle and Hawking wrote a very famous paper with the exact name "Wavefunction of the Universe". You can see the abstract here but the paper is not available for free download:
http://prola.aps.org/abstract/PRD/v28/i12/p2960_1
Anyhow, Gell-Mann calls Hartle an expert on gravity, so I think you'll find that he is. That Hartle knows gravity very well was my original point.
wipeout said:
Interesting. I didn't know about their work on quantum cosmology. All I knew of was Hawking's earlier work on the global properties of spacetime.
Yes. I believe Everett's famous thesis in which he expounded the many-worlds interpretation of quantum mechanics had a very similar name, but not the same. "The Theory of the Universal Wavefunction," I think.
I certainly won't dispute that.