In 2007 a researcher, now at Harvard, conducted an experiement that transformed light into matter and then the matter so created was transformed back into light.
links:
http://www.google.com/search?client=...utf-8&oe=utf-8
To me, this seemed like the first experiment conducted that demonstrated that matter could be created.
Perhaps 'light' has an 'operating parameter' and if (when?) light can be slowed down (contra Einstein) that it experiences a 'change of state' into mass/matter.
We know that we can transform mass into energy (E=MC squared) and the experiment, referenced above, did the opposite.
Perhaps Einstein's E=MC squared may provide a fleeting insight where (transposed) E divided by C squared = M but this inversion of Einstein's equation does not account for thermal variances (?).
The press coverage for this event does not shed much light on the overall process and the Harvard article (link)
http://www.news.harvard.edu/gazette/...08/99-hau.html seems to understate the significance and implications of the experiment.
Here is a quote from the Harvard article:
"A weird thing happens to the light as it enters the cold atomic cloud, called a Bose-Einstein condensate. It becomes squeezed into a space 50 million times smaller. Imagine a light beam 3,200 feet (one kilometer) long, loaded with information, that now is only a hair width in length but still encodes as much information." (end quote)
Einstein would counter (I believe) that the experiment did not 'slow the speed of light' but, rather, warped space (compressed distance) and produced the illusion of slowing the speed of light.
Nevertheless, the experiment has mind-boggling implications. It is as though we can close our eyes and then blink once and have the brief image 'frozen' into a fixed (mass) configuration.
I often analyze this quantum stuff by leaving the mid-ranges and going to the extremes.... in other words, a 'blackhole' could be thought of as a massive accumulation of light that is so tightly compressed that it forms into infinite mass(?) as the velocity of light is brought to a standstill and time, as we know it, stops. Further analysis (mine) produces a 'chicken/egg' scenario that has not, as yet, provided any deeper insight. In other words, what event has to occur (initially) that causes light speed to decelerate? (again, contra Einstein).
The (most probable) answer is a radical decrease in temperature (460 degrees below zero Fahrenheit).
link:
http://www.colorado.edu/physics/2000...hat_is_it.html
This link (above) provides a graphic with a slider bar that enables you to watch atoms (activity) as temperature declines (Bose-Einstein condensate). The main problem that I see, in associating 'atoms' (Bose-Einstein condensate) and 'light' is that 'light' is thought to be massless (photons not atoms). Perhaps decreased temperature stops atoms from emitting photons? (Atom-photon entanglement).
As for myself, I only have the most primitive understanding of these processes and 'knowledge' about these matters should not be inferred by my use of big words like "Bose-Einstein condensate".
None of this explains how to get light into matter, in a stable form and independent of temperature, but it does indicate that matter/energy transformations can be a 'two-way street'.
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