If light is both a particle & a wave then explain how is it possible that a light wave trillions of?

These are the largest objects that so far showed deBroglie matter-wave interference. Whether objects heavier than the Planck mass (about the weight of a large bacterium) have a de Broglie wavelength is theoretically unclear and experimentally unreachable; above the Planck mass a particle's Compton wavelength would be smaller than the Planck length and its own Schwarzschild radius, a scale at which current theories of physics may break down or need to be replaced by more general ones. Recently Couder, Fort, et al.

Showed25 that we can use macroscopic oil droplets on a vibrating surface as a model of wave–particle duality—localized droplet creates periodical waves around and interaction with them leads to quantum-like phenomena: interference in double-slit experiment,26 unpredictable tunneling27 (depending in complicated way on practically hidden state of field), orbit quantization28 (that particle has to 'find a resonance' with field perturbations it creates—after one orbit, its internal phase has to return to the initial state) and Zeeman effect. Wave–particle duality is deeply embedded into the foundations of quantum mechanics, so well that modern practitioners rarely discuss it as such. In the formalism of the theory, all the information about a particle is encoded in its wave function, a complex-valued function roughly analogous to the amplitude of a wave at each point in space.

This function evolves according to a differential equation (generically called the Schrödinger equation), and this equation has solutions that follow the form of the wave equation. Propagation of such waves leads to wave-like phenomena such as interference and diffraction. The particle-like behavior is most evident due to phenomena associated with measurement in quantum mechanics.

Upon measuring the location of the particle, the particle will be forced into a more localized state as given by the uncertainty principle. When viewed through this formalism, the measurement of the wave function will randomly "collapse", or rather "decohere", to a sharply peaked function at some location. The likelihood of detecting the particle at any particular location is equal to the squared amplitude of the wave function there.

The measurement will return a well-defined position, (subject to uncertainty), a property traditionally associated with particles. It is important to note that a measurement is only a particular type of interaction where some data is recorded and the measured quantity is forced into a particular eigenstate. The act of measurement is therefore not fundamentally different from any other interaction.

Although this picture is somewhat simplified (to the non-relativistic case), it is adequatecitation needed to capture the essence of current thinking on the phenomena historically called "wave–particle duality". Following the development of quantum field theory the ambiguity disappeared. Although there is still debate as to whether one should accept the field as "real", the debate over using the term wave or particle is rendered meaningless.

The field permits solutions that follow the wave equation, which are referred to as the wave functions. The term particle is used to label the irreducible representations of the Lorentz group that are permitted by the field. An interaction as in a Feynmann diagram is accepted as a calculationally convenient approximation where the outgoing legs are known to be simplifications of the propagation and the internal lines are for some order in an expansion of the field interaction.

Since the field is non-local and quantized, the phenomena which previously were thought of as paradoxes are explained. Below is an illustration of how wave–particle duality is consistent with De Broglie's hypothesis and Heisenberg's uncertainty principle (above). In one dimension for one particle, the probability of finding a particle in space at some time t (not shown) is distributed as a (complex-valued) waveform through space, mathematically described by the particle's wave function?.

The larger the amplitude, the more likely the particle is to be found. For the plane wave (left), the wave-like probability distribution? The particle is likely to be found anywhere, due to the periodicity of the wave.

For the wavepacket (right),? Is localized and the particle can be found within some confined region of space. Wave–particle duality is an ongoing conundrum in modern physics.

Most physicists accept wave-particle duality as the best explanation for a broad range of observed phenomena; however, it is not without controversy. Alternative views are also presented here. These views are not generally accepted by mainstream physics, but serve as a basis for valuable discussion within the community.

The pilot wave model, originally developed by Louis de Broglie and further developed by David Bohm into the hidden variable theory proposes that there is no duality, but rather a system exhibits both particle properties and wave properties simultaneously, and particles are guided, in a deterministic fashion, by the pilot wave (or its "quantum potential") which will direct them to areas of constructive interference in preference to areas of destructive interference. This idea is held by a significant minority within the physics community. At least one physicist considers the "wave-duality" a misnomer, as L.

Ballentine, Quantum Mechanics, A Modern Development, p. When first discovered, particle diffraction was a source of great puzzlement. In the early experiments, the diffraction patterns were detected holistically by means of a photographic plate, which could not detect individual particles.

As a result, the notion grew that particle and wave properties were mutually incompatible, or complementary, in the sense that different measurement apparatuses would be required to observe them. That idea, however, was only an unfortunate generalization from a technological limitation. Today it is possible to detect the arrival of individual electrons, and to see the diffraction pattern emerge as a statistical pattern made up of many small spots (Tonomura et al.

Evidently, quantum particles are indeed particles, but whose behaviour is very different from classical physics would have us to expect. Afshar's31 experiment (2007) has demonstrated that it is possible to simultaneously observe both wave and particle properties of photons. At least one scientist proposes that the duality can be replaced by a "wave-only" view.

Carver Mead's Collective Electrodynamics: Quantum Foundations of Electromagnetism (2000) analyzes the behavior of electrons and photons purely in terms of electron wave functions, and attributes the apparent particle-like behavior to quantization effects and eigenstates. Mead has cut the Gordian knot of quantum complementarity. He claims that atoms, with their neutrons, protons, and electrons, are not particles at all but pure waves of matter.

Mead cites as the gross evidence of the exclusively wave nature of both light and matter the discovery between 1933 and 1996 of ten examples of pure wave phenomena, including the ubiquitous laser of CD players, the self-propagating electrical currents of superconductors, and the Bose–Einstein condensate of atoms. This double nature of radiation (and of material corpuscles)...has been interpreted by quantum-mechanics in an ingenious and amazingly successful fashion. Instead, one has a single, holistic continuum, wherein what were formerly called discrete, separable particles of matter are instead the infinite number of distinguishable, though correlated manifestations of this continuum, that in principle is the universe.

Hence, wave-particle dualism, which is foundational for the quantum theory, is replaced by wave (continuous field) monism. The many-worlds interpretation (MWI) is sometimes presented as a waves-only theory, including by its originator, Hugh Everett who referred to MWI as "the wave interpretation". The Three Wave Hypothesis of R.

Horodecki relates the particle to wave. 3637 The hypothesis implies that a massive particle is an intrinsically spatially as well as temporally extended wave phenomenon by a nonlinear law. According to M.

Sanduk this hypothesis is related to a hypothetical bevel gear model. 38 Then both concepts of particle and wave may be attributed to an observation problem of the gear. It has been argued that there are never exact particles or waves, but only some compromise or intermediate between them.

One consideration is that zero dimensional mathematical points cannot be observed. Another is that the formal representation of such points, the Kronecker delta function is unphysical, because it cannot be normalized. Parallel arguments apply to pure wave states.

"Such positions states are idealised wavefunctions .. Whereas the momentum states are infinitely spread out, the position states are infinitely concentrated. Relational quantum mechanics is developed which regards the detection event as establishing a relationship between the quantized field and the detector. The inherent ambiguity associated with applying Heisenberg's uncertainty principle and thus wave–particle duality is subsequently avoided.

Although it is difficult to draw a line separating wave–particle duality from the rest of quantum mechanics, it is nevertheless possible to list some applications of this basic idea. Wave–particle duality is exploited in electron microscopy, where the small wavelengths associated with the electron can be used to view objects much smaller than what is visible using visible light. Similarly, neutron diffraction uses neutrons with a wavelength of about 0.1 nm, the typical spacing of atoms in a solid, to determine the structure of solids.

"Quantum mechanics: Myths and facts". Young & Geller. "Light as a Particle" (Web page).

"Wave–Particle Duality" (Web page). Georgia State University, Department of Physics and Astronomy. Juffmann, Thomas et al (25 March 2012).