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> Joe Jenkins email@example.com Wrote:
>Lets say a non-destructive backup technology becomes available in
>2010. This technology allow us to place a subject on a MRI-like table
>and rotate his head while a stationary light source generates short
>bursts of photons. A sensor on the other side of the subjects head is
>able to register only the photons arriving first that passed through
>the brain without any collisions whatsoever. The photons that collide
>with brain matter arrive too late and are not part of the image
>created for that pulse of light because they had to bounce once or
>twice and thus travel further and thus take longer to exit the other
>side of the brain. The head is slowly rotated and a series of images
I had a similar idea a while back and wrote a post about it on March 15 1997.
A few years ago I read about a technique for seeing through opaque objects with optical LASER pulses of astronomical intensity but modest energy, I remember seeing a picture of a newspaper taken through several inches of milk, you could still read it. I wonder if a device working on a similar principle could be used to obtain enough information from a nondestructive brain scan to upload a mind.
When most photons that make up an image enter milk they are refracted off the many fat globules in solution, if any photons come out the other side of the milk container they have been bounced around so much that the information on where they originated is hopelessly scrambled, all you would see is a diffuse glow, not an image. However, a few very lucky photons, perhaps one in a billion trillion, perhaps less, can make it through the milk without interacting with anything. Because these rare photons don't get bounced around but take a shorter direct path, they are the first photons to emerge from the milk. If you only looked at those early photons and ignored the much more numerous later ones, you could see an image and not just a general glow.
I don't remember the researcher's name or the exact specifications of his LASER, but I do know that intensities as high as 10^18 watts per square centimeter and pulses as short as 10-14 seconds have been achieved with table top LASERS. You'd want to squeeze every bit of information out of the rare photons that make up the image, so just recording their amplitude, as in photography, would not be good enough, you'd want to know their phase too, and that means Holography. As a bonus, you wouldn't have to worry about depth of field focusing problems, and the reference beam for the Hologram could act as a super fast camera shutter, use a different frequency for the reference beam pulse and put in a filter for the original frequency.
10^-14 seconds might be too long for a safe brain scan at the enormous intensities required, and light can travel about a tenth of a millimeter in that time, but I'll bet a soft X ray LASER could be built with a lot shorter pulse than that, I just hope it can be made short enough that the brain is not vaporized. Anyway it's just a thought.
John K Clark firstname.lastname@example.org
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