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Mordred

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Everything posted by Mordred

  1. Well it wouldn't be a legal radio antennae in The US by today's regulations. Max transmit power for UHF and VHF antennaes are usually 25 watts. 50 watts with specific licensing. Even then most mobile radios for extra long range max out at 100 watt. I've never encountered one higher even on the repeaters. Highest I've come across in 3 different models is 100 watt but that takes licensing to run at that level. At least in accordance with today's regs in US and Canada. Portable radios ie handheld are 5 to 10 watts
  2. Your welcome that's only volume one of three books available on that website. There is very little in science we call fact. TBH I can't think of a single example. Everything in science is modelled or explained as to the best of our knowledge or model to measurements and observation. This isn't necessarily fact. If for some unpredicted evidence comes along our knowledge and understanding must conform.
  3. Oh man you really have to sit down and look at how vectors work with force. This is basic physics stuff. when you jump you exert a downward force. The ground exerts an equal and opposite reaction. If it didn't you wouldn't go up. I suggest you study this basic physics textbook. http://www.feynmanlectures.caltech.edu/I_toc.html In particular chapter 9
  4. You really need to study action/reaction in Newtons laws. If this law didn't exist. You push on the ground if there was no counter push you would sink. Much like quicksand. Ever fire a gun? What do you think recoil is? How do you think you can walk. You push with your feet backwards the ground pushes back. If it didn't you wouldn't gain forward momentum.
  5. Is it? We're talking about Newtons laws of inertia. In Euclidean geometry these three laws does an excellent approximation. It's currently used by engineers mechanics etc far more than GR. Works well for everyday applications. The main difference between the two comes into play via geometry/coordinate change. In curved space time those laws still apply, just under different coordinates. For example Newtons laws of inertia works under the Three Geodesic transformations. Those laws still hold true. I. Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it. II. The relationship between an object's mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors in this law the direction of the force vector is the same as the direction of the acceleration vector. III for every action there is an equal and opposite reaction. your objection is based on the use of the term force. "In physics, a force is any interaction that tends to change the motion of an object. In other words, a force can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate. Force can also be described by intuitive concepts such as a push or a pull." Space time geometry certainly counts as an interaction. It certainly tends to change the motion of objects. By any definition space time fits the bill of a force.
  6. Einstein would have known that himself. It's part of the scientific method.Here is a translated quote from one of his papers. Keep in mind he is specifically stating in Euclidean geometry (flat). Newtonian physics is highly accurate, but only valid until you have space time geometry changes. "As is well known, the fundamental law of the mechanics of Galilei-Newton, which is known as the law of inertia, can be stated thus: A body removed sufficiently far from other bodies continues in a state of rest or of uniform motion in a straight line. This law not only says something about the motion of the bodies, but it also indicates the reference-bodies or systems of coordinates, permissible in mechanics, which can be used in mechanical description. The visible fixed stars are bodies for which the law of inertia certainly holds to a high degree of approximation. Now if we use a system of co-ordinates which is rigidly attached to the earth, then, relative to this system, every fixed star describes a circle of immense radius in the course of an astronomical day, a result which is opposed to the statement of the law of inertia. So that if we adhere to this law we must refer these motions only to systems of coordinates relative to which the fixed stars do not move in a circle. A system of co-ordinates of which the state of motion is such that the law of inertia holds relative to it is called a " Galileian system of co-ordinates." The laws of the mechanics of Galflei-Newton can be regarded as valid only for a Galileian system of co-ordinates." http://www.marxists.org/reference/archive/einstein/works/1910s/relative/relativity.pdf An authorized reprint of Einsteins Special relativity paper Here is an excellent paper on the difficulty in quantifying gravity. On particular GR to QM. http://arxiv.org/abs/gr-qc/0004005 ( by the way your arguments are getting better ) just needs polishing. As well as recognizing that regardless of how robust and accurate GR is. It's not the final chapter on gravity.
  7. In science any theory until proven false is viable. Get used to it. Its more accurate to state until we can quantize gravity to particle to particle interactions. Or prove this to be impossible. All forms of geodesics is a space time curvature path. Just not the same path. Three geodesics are involved. Null, spacelike and time like. Particles with mass follow time like specifically free falling particles. http://www.physics.usyd.edu.au/~luke/research/masters-geodesics.pdf Key note there is an excellent line in this article. "Energy=curvature"
  8. Here you can see how GR affects massless photons differently than massive particles. "massless particles like the photon instead follow null geodesics (replace −1 with zero on the right-hand side of the last equation). " https://en.m.wikipedia.org/wiki/Geodesics_in_general_relativity Whether or not you wish to call gravity a curvature influence only or a force is entirely up to you. However GR doesn't necessarily invalidate the graviton. It's still incomplete in that regard. Wrong . a property of matter by which it continues in its existing state of rest or uniform motion in a straight line, unless that state is changed by an external force. Mass is resistance to change in inertia. Not inertia itself.
  9. Gravity only directly influences bodies and particles with mass. Hence photons with no rest mass follows null geodesics. While particles with mass following time like geodesics. You can't have space time deformation without energy. Energy is equivelent to mass via e=mc^2. The problem is you keep thinking mass implies matter. It doesn't. Any form of energy even. Gravitation wave can cause gravity via resistance to inertia=mass. The problem you seem to have is that you fight against the term mass. Yet the term itself doesn't mean due to matter. It means resistance to inertia change.
  10. (PS don't completely trust wiki links. The anti gravity description on that link is misleading). It's anti gravity like. However works via negative vacuum w=-1 [latex]w=\frac{\rho}{p}[/latex] The influence whatever the cause still boils down to sources of gravity causes movement (attraction). There is no source of anti gravity. Gravity attracts only. Lambda is oft misrepresented by stating its anti gravity like. This does not mean the same thing as anti gravity. So it is semantics. GR describes the cause of this movement due to space time deformation. Newton due to force. In both cases objects move towards each other due to gravity. The source of gravity in both cases has the mass relation included. An object doesn't need its own peculiar movement. You place a ball at rest on a table. You can still measure its weight even though it is at rest. ( where is the movement?) Gravity is still influencing that ball even though it is at rest. That should tell you there is still an attraction even for objects at rest. GR and Newton both have different explanations for this but both GR and Newton recognize gravity attracts. The main difference is "Is that attraction due to curvature geometry only ? (GR) or is there a force carrying gravitational boson? Graviton. Neither answer is ruled out. GR cannot quantize gravity at the quantum regime. Single particle interactions gravity becomes immeasurable. Simply too weak particle to particle. We cannot generate nearly enough energy to create a graviton. So we still haven't found any spin 2 particles. If we do it's most likely the graviton as gravity follows spin 2 statistics. Hopefully one day quantum gravity solves that quantizing problem. Till then you can accurately describe gravity as a force or due to curvature. Either or mass does attract mass via one of the two mentioned processes (Possibly even both) In either case mass is simply "resistance to inertia changes" any Form of binding energy can cause mass. The strong force is simply the most common source. The Higgs field only affects certain particles.
  11. However you wish to define how gravity attracts as either due to force or spacetime curvature is up to you. Either way gravity attracts mass in that mass moves to sources of mass. Even if the cause of gravity is due strictly to space time curvature. The mathematics still work for Newtons universal laws of gravity. For everyday applications. There is nothing wrong in calling this a force. Particularly since Newtons laws of inertia can still be applied. Your objection boils down to mere semantics. And yes I am confident of my answer. I already posted to you the ideal gas law applications including the acceleration equation in the FLRW metric. You once stated you have a copy of Barbers Rydens "Introductory to Cosmology". Please review the section. "Learn to love Lambda"
  12. Sorry I didn't answer your math question. I was busy and when I saw it figured you would have googled a math review. Anyways that being said this last post you still seem to be having some trouble in how expansion works. Take the average energy/mass density of the cosmological constant (negative vaccuum.) The average energy density is 6.7*10^-10 joules/m^3. It's extremely weak. So weak that locally gravity and gravitational bound objects can easily overcome the cosmological constant. Where the cosmological constant has the most influence is where there is a significant void between large scale structures. So yes both effects can be present in the exact same region, it's just the weaker influence is overpowered. Here is a useful analogy. Take a rock and suspend it. The Earths gravity attracts the rock yet the strong force binding the rock is stronger. So the rock maintains its shape. Increase the gravity (say a BH) the rock undergoes spagetification. Gravity vs the cosmological constant is the same scenario.
  13. Possibly, like I stated there is still studies underway. As to feasability. That too is a yes. NASA has already been exploring this option. https://www.google.ca/url?sa=t&source=web&cd=2&ved=0CCcQFjABahUKEwjukeDdz9vGAhWLOT4KHcpsAPg&url=http%3A%2F%2Fntrs.nasa.gov%2Farchive%2Fnasa%2Fcasi.ntrs.nasa.gov%2F20080036588.pdf&rct=j&q=nasa%20wireless%20power%20transmission&ei=xYalVa6bMovz-AHK2YHADw&usg=AFQjCNHdEETW3wGazwsevEaMQlGqXMZTCg&sig2=bC7iK4T20ozPMLL79ylL5g
  14. Here Is some possible side effects currently under research. http://www.nature.com/news/electronics-noise-disorients-migratory-birds-1.15176 http://www.jstor.org/stable/1941976?seq=1#page_scan_tab_contents
  15. Is human organs the only thing at risk? The SAR values I've come across are developed for human risk. What about insects, plants and birds. I have encountered any surveys on this. Might bear looking into. The main risk is although your talking low frequency. You have a continuous stream. This alters the safe threshold limits on exposure times. When I worked radio towers, all transmitters had to be shutdown. Regardless of transmission power and frequency. The only exception was when you were aligning microwave links. (Directional) even then we made sure to be behind the transmitter. The effects of Radio wave pollution is still largely under study. We simply do not know for sure which frequencies and radiative power is considered 100% safe. As such most sites state low frequency non thermal effects are still under debate. although sunlight on Earth is on a daily schedule, this can be countered via battery storage. Far safer as your not introducing added radiwaves. Plants, insects and wildlife have already adapted to the sunlight itself.
  16. Neutrinos as far as I know follow Fermi Dirac statistics. The majorana statistics application to neutrinos is still hypothetical( not conclusive enough atm). To the best of my knowledge. In so far as a majarana neutrino would be a new type. As yet undiscovered.
  17. With this meaningless vent rap I vote ban. We don't require or ask for your volatile and juvenistic methodology. This is a physics forum. Not a vent outlet. Come back when Your more under control to rational thought.
  18. Have you ever looked at density wave theory in regards to spiral arms in a galaxy ? Have you ever applied Keplers laws of rotation to galaxy curves ? In either Keplers laws or shell theorem. With or without DM ? Most importantly the universe isn't rotating. Galaxies yes, the universe no. A homogeneous and isotropic universe is based on a scale of 100 Mpc. Far large enough to considered a large body of galaxies lmao.
  19. Your better off with a radio watt meter. For diectivity look at Yagi antennae. https://en.m.wikipedia.org/wiki/Yagi-Uda_antenna I assume you have amateur radio licensing
  20. Sorry Mike but your no where near an expert in the field of Radio wave SAR values. That's the simple truth in the matter. Not to mention any interferance your proposal can potentially have on communications over a broad area.
  21. No prob, you'd be amazed how many posters in speculations ignore vector quantities. However the majority of formulas include vector and scalar quantities. Ie f=ma mass is scalar acceleration and force is vector. +1
  22. The problem is kinetic energy is a measure of the quantity of work. Not the direction the work is applied. Several of your statements read as if you have kinetic energy=movement. Let's look at this statement " Universe doesn't need energy tensor to make motion; all it needs is energy. Mathematical descriptions need tensors; nothing else does." It needs energy scalar (kinetic energy of you like) and direction vector. Velocity or momentum. Tensors simply combine the two in a non coordinate system. You can use the same tensor relations regardless of coordinates. In physics, the kinetic energy of an object is the energy that it possesses due to its motion.[1] It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. it's the measure of work for velocity. However momentum is velocity * mass. Ie a body already in motion Or Newtons laws of gravity. The relationship for kinetic energy to momentum does have a formula. [latex]E_k=\frac{p^2}{2m}[/latex] but remember in inelastic collisions kinetic energy can be lost to heat and sound. The reason why velocity and momentum terms are used in GR and SR is that both terms are conserved and both include kinetic energy+direction. However both are also observer dependant. Multi particle systems are typically described via velocity and momentum when describing how one influences the other. Not via kinetic energy. That's just your scalar quantity. That's the point I'm getting at. If your describing bodies in motion use velocity or momentum. Or for that matter motion period. If you don't include the vectors of particles in motion you won't take into account the shear stress aspects of space time curvature or frame dragging. Force is also a vector quantity. Another key note matter wave uses momentum. The connection to particle waves in SR requires two formulas one for energy and one for Momentum. https://en.m.wikipedia.org/wiki/Matter_wave
  23. You will never get this until you come to grips that physics has specific units and definitions for its terminology. So unless you learn those definitions and resulting units. Your limitting yourself. Your not going to change something as long lived and basic as to how kinetic energy is defined. Nor why physics and math states it's different from momentum and velocity. Think of it this way take object a with x amount of kinetic energy. Colliding with ball b at rest. Which direction will ball b move? As you only applied kinetic energy to ball a you haven't established a direction. The point your missing is when ball a strikes ball b. The work is done by its momentum. Not it's kinetic energy. Here maybe a basic set of calculations will tell you the difference. http://www.batesville.k12.in.us/physics/phynet/mechanics/energy/KENOTMomentum.html Meatball vs truck The other point is kinetic energy is not a conserved property. Momentum is. A bullet can lose kinetic energy due to heat loss or gain kinetic energy to friction Please look at how basic terms are defined. Thermal energy is directly related to temperature. We can't see individual atoms vibrating, but we can feel their kinetic energies as temperature. When there's a difference between the temperature of the environment and a system within it, thermal energy is transferred between them as heat. Momentum [latex] p=mv[/latex] Kinetic energy [latex]\frac{1}{2}mV^2[/latex] Note not the same formulas. If you try using kinetic energy instead of momentum in GR you will get the wrong answer for say a falling body. Not to mention throwing your unit conversion s off. Kinetic energy being measured in joules where one joule =1 kg*m^2/s^2 Momentum being Kg*m/s.
  24. Why do you keep missing the key elements? Kinetic energy isn't the same as velocity or momentum. Kinetic energy is a scalar quantity. Velocity and momentum are both vector quantities. You cannot state kinetic energy Is the same as momentum or velocity as kinetic energy has no direction terms. I don't know how many times I've had to explain this simple principle. You keep throwing kinetic energy into your explanations when you should be using velocity or momentum. Not kinetic energy. The stress energy momentum tensor INCLUDES both for good reason. It's called the lanquage of mathematics.
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