If more than one wavelength is present ( as is usually the case ), one must sum or integrate over the spectrum of wavelengths present to get the total luminous intensity.

If measured instead per unit wavelength, using Wien's law, the peak is at 1. 06 mm corresponding to a frequency of 283 GHz.

If the width of the slits is small enough ( less than the wavelength of the laser light ), the slits diffract the light into cylindrical waves.

If the width of the slits is greater than the wavelength, the Fraunhofer diffraction equation gives the intensity of the diffracted light as:

If applied to optical wavelengths, this manifests itself as a change in the colour of visible light as the wavelength of the light is increased toward the red part of the light spectrum.

If the beam of light is not orthogonal ( or rather normal ) to the boundary, the change in wavelength results in a change in the direction of the beam.

If the pitch of this twist is on the order of the wavelength of visible light, then interesting optical interference effects can be observed.

If two waves of the same wavelength and frequency are in phase, both the wave crests and wave troughs align.

If the wavelength is much shorter than the target's size, the wave will bounce off in a way similar to the way light is reflected by a mirror.

If the wavelength is much longer than the size of the target, the target may not be visible because of poor reflection.

If λ represents wavelength and f represents frequency ( note, λf = c where c is the speed of light ), then z is defined by the equations:

If the waves have the correct frequency ( or wavelength ) and polarization, their energy can be transferred to the charged particles in the plasma, which in turn collide with other plasma particles, thus increasing the temperature of the bulk plasma.

If each mode received an equal partition of energy, the short wavelength modes would consume all the energy.

If scatterers are arranged symmetrically with a separation d, these spherical waves will be in sync ( add constructively ) only in directions where their path-length difference 2d sin θ equals an integer multiple of the wavelength λ.

If λ < sub > c </ sub > is the central wavelength, λ < sub > 0 </ sub > is the central wavelength at normal incidence, and n < sup >*</ sup > is the filter effective index of refraction, then:

If the surface is rough enough to create path-length differences exceeding one wavelength, giving rise to phase changes greater than 2π, the amplitude, and hence the intensity, of the resultant light varies randomly.

If a photographic plate or another 2-D optical sensor is located within the scattered light field without a lens, a speckle pattern is obtained whose characteristics depend on the geometry of the system and the wavelength of the laser.

If a particle were massive enough that its Compton wavelength and Schwarzschild radius were approximately equal, its dynamics would be strongly affected by quantum gravity.

If the source has a maximum overall dimension or aperture width ( D ) that is large compared to the wavelength λ, the far-field region is commonly taken to exist at distances from the source, greater than Fresnel parameter S = D < sup > 2 </ sup >/( 4λ ), S > 1.

If photons of a particular wavelength are absorbed by matter, then when we observe light reflected from or transmitted through that matter, what we see is the complementary color, made up of the other visible wavelengths remaining.

If only a single atom of hydrogen were present, then only a single wavelength would be observed at a given instant.

If the wavelength of light far exceeds the particle dimensions, the particles can be treated as electric dipoles in an electric field.

If light of a fixed frequency / wavelength / color ( as from a laser ) is assumed, then the time-harmonic ( frequency-domain ) form of the optical field is given as:

If a particle and antiparticle are in the appropriate quantum states, then they can annihilate each other and produce other particles.

If denotes the quantum state of a particle ( n ) with momentum p, spin J whose component in the z-direction is σ, then one has

If a suitably sized quantum computer capable of running Grover's algorithm reliably becomes available, it would reduce a 128-bit key down to 64-bit security, roughly a DES equivalent.

If the quantum state is initially symmetric ( antisymmetric ), it will remain symmetric ( antisymmetric ) as the system evolves.

If S contains two elements that are not pairwise orthogonal ( in particular, the set of all quantum states includes such pairs ) then an argument like that given above shows that the answer is no.

If the error rate is small enough, it is thought to be possible to use quantum error correction, which corrects errors due to decoherence, thereby allowing the total calculation time to be longer than the decoherence time.

If the theory of quantum gravity also achieves a grand unification of the other known interactions, it is referred to as a theory of everything ( TOE ).

If one used Planck's energy quanta, and demanded that electromagnetic radiation at a given frequency could only transfer energy to matter in integer multiples of an energy quantum hν, then the photoelectric effect could be explained very simply.

If certain quantum inequalities conjectured by Ford and Roman hold, then the energy requirements for some warp drives may be absurdly gigantic as well as negative, for example the energy equivalent of − 10 < sup > 64 </ sup > kg might be required to transport a small spaceship across the Milky Way galaxy.

If the universe is described by an effective local quantum field theory down to the Planck scale, then we would expect a cosmological constant of the order of.

:" If the essential frequency range is limited to B cycles per second, 2B was given by Nyquist as the maximum number of code elements per second that could be unambiguously resolved, assuming the peak interference is less half a quantum step.

If a quantum computer with a sufficient number of qubits were to be constructed, Shor's algorithm could be used to break public-key cryptography schemes such as the widely used RSA scheme.

If true, sonoluminescence may be the first observable example of quantum vacuum radiation.

If quantum electrodynamics were an exact theory, the fine-structure constant would actually diverge at an energy known as the Landau pole.

If more than one quantum mechanical state is at the same energy, the energy levels are " degenerate ".

If quantum mechanics were to be applicable to macroscopic objects, there must be some limit in which quantum mechanics reduces to classical mechanics.

If the effects of the quantum mechanical nuclear motion are to be studied, for instance because a vibrational spectrum is required, this electronic computation must be in nuclear coordinates.

If a more general measurement is made that detects the system in a state then the system makes a " jump " or quantum leap from the original state to the final state with probability of.

If the factor i were absent, the H matrix would be antihermitian and would have purely imaginary eigenvalues, which is not the traditional way quantum mechanics represents observable quantities like the energy.

If the middle layer is made thin enough, it acts as a quantum well.

If parity transforms a pair of quantum states into each other, then the sum and difference of these two basis states are states of good parity.

If we allow the elements of the system to use quantum computation, the system is called a quantum interactive proof system, and the corresponding complexity class is called QIP.

If we introduce a vector then each quantum state corresponds to a point in ' n-space ' with energy