enquirealways
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If an extremely large no. ( may be infinite) waves are concentrated at one point, what effects can happen?
jtbell said:Waves of what?
Classically, multiple waves simply superpose ("add up") without affecting each other, if their differential wave equation is linear.
With very high energy densities, the linear assumption may no longer be true. With light waves, there's a whole field of "nonlinear optics" in which quantum effects come into play at high energy densities.
You can decompose any waveform into an infinite number of components. As for formation of particles:enquirealways said:I mean if infinitely large no. of EM waves concentrate at one point,
A.T. said:You can decompose any waveform into an infinite number of components. As for formation of particles:
http://en.wikipedia.org/wiki/Matter_creation
enquirealways said:If an extremely large no. ( may be infinite) waves are concentrated at one point, what effects can happen?
UltrafastPED said:Laser physicists do this all the time: concentrate light into small regions of space and time.
The spatial part is done through deformable mirrors; this is done in order to correct phase errors. Modern telescopes also use this principle. See http://spie.org/x87035.xml
The temporal part is done via laser pulse compression; this is the realm of the "ultrafast" lasers, lasers with pulse duration less than one picosecond (10^-12 seconds). This type of laser does not yield a narrow wavelength; it requires greater and greater bandwidth (=range of wavelengths/frequencies) in order to generate shorter pulses. Few femtosecond (10^-15 seconds) are regularly generated today.
The trick is to get a short pulse duration along with more energy in the pulse; power = energy/time, so the power density can be increased by increasing the pulse energy, or decreasing the pulse duration. Both can be done together with a chirped pulsed amplification (CPA) laser.
The irradiance is a measure of power delivered per unit of area; with a well focused laser the "spot size" is limited by the wavelengths of the light; the best that can be done is a spot about one wavelength in diameter. So for a typical CPA laser running in the near infrared (NIR) at 800 nm, the minimum spot size is about one micron in diameter.
As the power delivered increases, so the number of effects which can be measured. At 10^13 watts/cm^2 very fine holes can be "drilled" through thin sheets of metal - without any debris or signs of melting being left behind. This effect is exploited in modern laser eye surgery, and in micro-machining.
At 10^19 watts/cm^2 when delivered upon a metal or ceramic target, electron-positron pairs can be created.
At 10^22 watts/cm^2 electron, neutron, and proton beams can be generated, along with x-rays.
All of these experiments have been conducted in multiple laser labs. It is generally known as non-linear optics, or high field optical science. There are many threads of research using the same tools.
You can read more about this here: http://cuos.engin.umich.edu/
I did my dissertation at CUOS, creating far from equilibrium states in materials, and measuring the material response at sub-picosecond time steps.
enquirealways said:Thanks for an elaborate reply.
So, at the present moment, creation of a black hole doesn't seem a possibility via this method.