Question about gravity
in [Physics]
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From: kenseto on 16 Mar 2010 13:25 On Mar 16, 9:55 am, PD <thedraperfam...(a)gmail.com> wrote: > On Mar 16, 8:49 am, kenseto <kens...(a)erinet.com> wrote: > > > > > > > On Mar 15, 2:57 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Mar 15, 1:43 pm, kenseto <kens...(a)erinet.com> wrote: > > > > > On Mar 15, 2:27 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > On Mar 15, 1:25 pm, "kens...(a)erinet.com" <kens...(a)erinet.com> wrote: > > > > > > > On Mar 15, 10:08 am, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > > > > On Mar 15, 9:04 am, kenseto <kens...(a)erinet.com> wrote: > > > > > > > > > On Mar 15, 6:43 am, "Peter Webb" > > > > > > > > > <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > > > > > > > > Not a whole lot to add to what Inertial in particular said. > > > > > > > > > > In GR, gravity is a virtual force in a similar way to centrifugal force in > > > > > > > > > Newton. In both cases its really an acceleration, and the force is just the > > > > > > > > > product (literally) of this acceleration and the mass of the object. > > > > > > > > > > Einstein in GR gave a geometric interpretation of what gravity is. This is > > > > > > > > > very appealing, because it provides a mechanism for force at a distance. > > > > > > > > > Wrong it provides no such physical mechanism. It merely assumes the > > > > > > > > existence of a physical entity caLLED the fabric of spacetime for the > > > > > > > > interacting object to follow. The problem with such assumption is: > > > > > > > > What is the fabric of spacetime physically? This question is relevant > > > > > > > > because SR/GR deny the existence of physical space. > > > > > > > > > Ken Seto > > > > > > > > What ? ".... SR/GR deny the existence of physical space......." > > > > > > > > What the devil are you saying man ????? > > > > > > > > The theory of relativity says that gravity IS deformation of space. > > > > > > > How can this same theory deny the existence of space ??? Better visit > > > > > > > your optometrist really, really soon. > > > > > > > Sigh...How can you deform space when space is defined by Einstein as > > > > > > "empty space".???? > > > > > > Being empty means it has no matter in it. Having no matter in it does > > > > > not mean that space cannot have physical properties. Physical > > > > > properties are not limited to matter. > > > > > Bullshit. fields are stresses in a solid medium occupying space > > > > according to steven weinberg > > > > Solid medium? He said nothing about an electric field being a stress > > > in a solid medium. > > > Do you just make this stuff up as you go along? > > > Hey idiot...His said that in his book "Dream of a final theory" > > I have that book. Cite the page. He does not say that fields are > stresses in a solid medium. > > > > > > Physical properties are not limited to matter. > > > > You know that there is a permittivity of EMPTY SPACE? You know there > > > is a permeability of EMPTY SPACE? You know there is an impedance of > > > EMPTY SPACE? You know there is a gravitational potential in EMPTY > > > SPACE > > > Empty space by definition cannot have property. > > That is incorrect. Empty space means devoid of matter. It does NOT > mean devoid of physical properties. Sure it does....no matter, no physical property. > > > permittvity and > > permeability are properties of a unique medium occupying space. > > That is incorrect. Read your freshman physics text where these > properties are discussed. These properties have been ascribed to empty > space for 150 years. Hey idiot These are not properties of empty space. They are properties of a medium occupying space. Ken Seto > > > > > > > Ken Seto- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text -
From: Unified_Perspective on 16 Mar 2010 13:39 On Mar 15, 1:42 am, MicroTech <henry.ko.nor...(a)gmail.com> wrote: > Can someone in this forum please help me sort out a confusing issue? > > Many scientists (including Einstein) claim that gravity is not a > force, but the effect of mass on the "fabric of spacetime". Many other > scientists refer to gravity as one of the four fundamental > interactions (three, if one considers the unification of the weak and > electromagnetic interactions, the "electroweak" force). > > Adding to the confusion, some scientists use both concepts with no > apparent difficulty: > Stephen Hawking (in his "A Brief History Of Time") first says that > gravity is not a force, but "simply" the effect of mass on the > "spacetime fabric" (making it "curve"). However, later in the book, he > refers to gravity as a fundamental force, carried by the graviton. > > So what is gravity, "really"? Does anybody really know? Or do we just > know its effects? > > Is it an attractive force "mutually pulling" the Earth towards the Sun > (and vice versa), "causing" the Earth to "fall" towards the Sun? And > due to the "forward motion" of the Earth, exactly matching the > "gravitational pull", it stays in orbit (just like any other > satellite, man-made or not); OR > > Is it the mass of the Sun that "curves spacetime", so no force is > interacting with the Earth, it is just moving in a "straight line" > along a "curved spacetime" geodesic? > > At my current level of understanding, gravity should be one or the > other, and not both... > > If Einstein's concept of "curved spacetime" is "correct," where does > the (hypothetical?) "graviton" (and/or "gravitino") enter the picture? > > References to published papers (accessible online) would be much > appreciated! > > Henry Norman Mr. Norman First and foremost I would like to compliment you for the quality of question you ask and the thoughtful manner in which it is phrased. The primary thing to remember is that physical scientists are often attempting to describe ever day effects in practical quantifiable ways. Newton's theory of a force of gravity does this very well especially in every day terms. You could go through an entire distinguished career in physical science and never come across a great need for anything better. The secondary thing to remember is that physical scientists often attempt to explain why and how things work. In this regard theories of force do not do so well. If you observe and quantify a physical effect it is quite simple to postulate that there must be a "force" that causes the effect, name the new force after yourself, and give the derived expression mathematically and your done. Fortunately physical reality is quite complex and a bit mysterious and we as scientists can derive great pleasure from coming up with "new" explanations and debating the merits of our opinions. In this regard Einstein's relativity does wonderfully well. It explains many things a bit better than mystical forces and it quantifies effects that Newton's equations can't. But, it doesn't explain everything. Which is good because then the game of physics would be over and we would have to go home and pay attention to our families which scientists are loathe to do. > > If Einstein's concept of "curved spacetime" is "correct," where does > the (hypothetical?) "graviton" (and/or "gravitino") enter the picture? > In terms of a better understanding of gravitons and such the explanation is simple in that space and time are fields, just like electric and magnetic fields, and gravitons are waves in these fields, just like E/M waves. I would say that relativity does not describe graviton waves in the same clear manner that Maxwell's equations describe electro-magnetic effects and so I would encourage you to continue your study and focus on filling this gap. Grand unified field theory will be very grand indeed when it is fully realized - in my opinion at least. If you would like a roadside sign that indicates a likely direction I would comment that Maxwell's original equations were in Quaternion's a type of linear matrix in which equations of the form (Ax + b) and (By + c) are combined to produce quadratic and higher order products that are then solved for the partial derivatives which are the "useful" form of the equations. Relativity uses a similar format and produces a somewhat similar set of partial derivative equations describing different fields of course. After careful research and contemplation I feel that there are five fields; space, time, electric, magnetic, and thermal. Therefor the general form of the equation of the universe should be a higher order polynomial - the product of (Sx + a) (Ty + b) (Im + c) (Je + d) (Kt +e) Where x=space, y=time, m=magnetic, e=electric, t=thermal and their respective coefficients are variables that quantify these respective field intensities while the adjuncts represent variables that quantify absolute offsets along the opposed axis from the origin. This is a very complex equation although it does simplify to down to Maxwell's subset for E/M and Einstein's for space/time so in theory Ohm's law could be derived from it as well as Newton's. It has taken me 40 years of hard work to get to this point and I keep chewing away at the problem, but I'm also passing along this sign post in hopes that you or someone like you may find the time and energy to develop the concept further and reconcile the result with the works of those on whom it is based. The multiple derivations that constitute the reconciliation will be far more difficult than the actual solution at this point, but if you or I or anyone else makes enough progress for the idea to gain traction then a multitude of others will lend their aide and support because that is the way science works - when it works at its best. > > At my current level of understanding, gravity should be one or the > other, and not both... > Your understanding is fine. These are opposing theories. Both work, SR works better. That is the short answer. The rest I included for selfish reasons - forgive me please. Anthony A. Gallistel
From: PD on 16 Mar 2010 13:57 On Mar 16, 12:25 pm, kenseto <kens...(a)erinet.com> wrote: > On Mar 16, 9:55 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Mar 16, 8:49 am, kenseto <kens...(a)erinet.com> wrote: > > > > On Mar 15, 2:57 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Mar 15, 1:43 pm, kenseto <kens...(a)erinet.com> wrote: > > > > > > On Mar 15, 2:27 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Mar 15, 1:25 pm, "kens...(a)erinet.com" <kens...(a)erinet.com> wrote: > > > > > > > > On Mar 15, 10:08 am, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > > > > > On Mar 15, 9:04 am, kenseto <kens...(a)erinet.com> wrote: > > > > > > > > > > On Mar 15, 6:43 am, "Peter Webb" > > > > > > > > > > <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > > > > > > > > > Not a whole lot to add to what Inertial in particular said. > > > > > > > > > > > In GR, gravity is a virtual force in a similar way to centrifugal force in > > > > > > > > > > Newton. In both cases its really an acceleration, and the force is just the > > > > > > > > > > product (literally) of this acceleration and the mass of the object. > > > > > > > > > > > Einstein in GR gave a geometric interpretation of what gravity is. This is > > > > > > > > > > very appealing, because it provides a mechanism for force at a distance. > > > > > > > > > > Wrong it provides no such physical mechanism. It merely assumes the > > > > > > > > > existence of a physical entity caLLED the fabric of spacetime for the > > > > > > > > > interacting object to follow. The problem with such assumption is: > > > > > > > > > What is the fabric of spacetime physically? This question is relevant > > > > > > > > > because SR/GR deny the existence of physical space. > > > > > > > > > > Ken Seto > > > > > > > > > What ? ".... SR/GR deny the existence of physical space......." > > > > > > > > > What the devil are you saying man ????? > > > > > > > > > The theory of relativity says that gravity IS deformation of space. > > > > > > > > How can this same theory deny the existence of space ??? Better visit > > > > > > > > your optometrist really, really soon. > > > > > > > > Sigh...How can you deform space when space is defined by Einstein as > > > > > > > "empty space".???? > > > > > > > Being empty means it has no matter in it. Having no matter in it does > > > > > > not mean that space cannot have physical properties. Physical > > > > > > properties are not limited to matter. > > > > > > Bullshit. fields are stresses in a solid medium occupying space > > > > > according to steven weinberg > > > > > Solid medium? He said nothing about an electric field being a stress > > > > in a solid medium. > > > > Do you just make this stuff up as you go along? > > > > Hey idiot...His said that in his book "Dream of a final theory" > > > I have that book. Cite the page. He does not say that fields are > > stresses in a solid medium. > > > > > Physical properties are not limited to matter. > > > > > You know that there is a permittivity of EMPTY SPACE? You know there > > > > is a permeability of EMPTY SPACE? You know there is an impedance of > > > > EMPTY SPACE? You know there is a gravitational potential in EMPTY > > > > SPACE > > > > Empty space by definition cannot have property. > > > That is incorrect. Empty space means devoid of matter. It does NOT > > mean devoid of physical properties. > > Sure it does....no matter, no physical property. I'm sorry, Ken, but physics has said differently for the last couple hundred years at least. You have it in your head that the only things real in the universe are material things, and that real physical descriptions are always about material and only material things, and that anything else that is described must be some kind of illusion or mathematical trick. This is not the case. Physical descriptions and in fact physical theories involve the immaterial as well as the material. To a physicist, for example, an electric field is a very real thing -- it can carry energy and momentum just as well as a material thing can -- and it is completely immaterial. Matter can disappear completely, yielding energy, but there are physical properties that remain (and some of them remain unchanged) through that disappearance. Light is not material, and yet it has wavelength, frequency, intensity, energy density, momentum, angular momentum, and a slew of other very physical properties. I could list a number of other examples that are also listed in your freshman physics book. If you did not read your freshman physics book, and because of that laziness, you came to believe that the only things that are physically real are material things, then you need to start over again with freshman physics. > > > permittvity and > > > permeability are properties of a unique medium occupying space. > > > That is incorrect. Read your freshman physics text where these > > properties are discussed. These properties have been ascribed to empty > > space for 150 years. > > Hey idiot These are not properties of empty space. They are properties > of a medium occupying space. Read your freshman physics book. It says differently. > > Ken Seto > > > > > > Ken Seto- Hide quoted text - > > > - Show quoted text -- Hide quoted text - > > > - Show quoted text - > >
From: mpc755 on 16 Mar 2010 13:58 On Mar 16, 1:20 pm, kenseto <kens...(a)erinet.com> wrote: > On Mar 16, 10:48 am, Sam Wormley <sworml...(a)gmail.com> wrote: > > > On 3/16/10 8:49 AM, kenseto wrote: > > > > Empty space by definition cannot have property. permittvity and > > > permeability are properties of a unique medium occupying space. > > > > Ken Seto > > > Haven't you notice this property of space that it in expanding > > at roughly 71 km/s/Mpc ? > > Wormy it is not space that is expanding. It is the objects in the > medium that are moving apart wrt each other. Good point. Below is an image of the jet stream the universe is, or an image of the local universe the jet stream is in: http://aether.lbl.gov/image_all.html The matter in the image is expanding in already existing three dimensional space.
From: mpc755 on 16 Mar 2010 14:03
On Mar 16, 1:57 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > Sure it does....no matter, no physical property. > > I'm sorry, Ken, but physics has said differently for the last couple > hundred years at least. > > You have it in your head that the only things real in the universe are > material things, and that real physical descriptions are always about > material and only material things, and that anything else that is > described must be some kind of illusion or mathematical trick. This is > not the case. Physical descriptions and in fact physical theories > involve the immaterial as well as the material. > > To a physicist, for example, an electric field is a very real thing -- > it can carry energy and momentum just as well as a material thing can > -- and it is completely immaterial. It's magic! > Matter can disappear completely, And more magic! > yielding energy, but there are physical properties that remain (and > some of them remain unchanged) through that disappearance. > > Light is not material, and yet it has wavelength, frequency, > intensity, energy density, momentum, angular momentum, and a slew of > other very physical properties. > Yes, and light waves propagate through a void! More magic! > I could list a number of other examples of magic! > that are also listed in your > freshman physics book. If you did not read your freshman physics book, > and because of that laziness, you came to believe that the only things > that are physically real are material things, then you need to start > over again with freshman physics. > > > > > permittvity and > > > > permeability are properties of a unique medium occupying space. > > > > That is incorrect. Read your freshman physics text where these > > > properties are discussed. These properties have been ascribed to empty > > > space for 150 years. > > > Hey idiot These are not properties of empty space. They are properties > > of a medium occupying space. > > Read your freshman physics book. It says differently. > Might want to check you magic bag; You forgot to mention 'virtual' particles and the future determines the past. |