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Scientists shine a laser through a human head

spectrum.ieee.org

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Re: Scientists shine a laser through a human head

#11

Post by hollerith »

>The group measured the times that millions of photons took to travel from a 1.2-watt laser emitting 800-nanometer wavelength light into one side of the head to a detector on the other side.

Sunlight contains copious amounts of 800-nm light, so this is probably completely non-hazardous.

Re: Scientists shine a laser through a human head

#12

Post by hagbard_c »

1970-01-01 wrote: post #7

The 2nd photo is named exactly as it looks; This isn't a parody? https://spectrum.ieee.org/media-library/a-3d-illustration-sh...

Looks like they used the ALT attribute as file name, maybe by feeding the image to a model which spit out this description. I do not see this as a sign of a hoax.

Re: Scientists shine a laser through a human head

#13

Post by ben_w »

hollerith wrote: post #11

>The group measured the times that millions of photons took to travel from a 1.2-watt laser emitting 800-nanometer wavelength light into one side of the head to a detector on the other side. Sunlight contains copious amounts of 800-nm light, so this is probably completely non-hazardous.

While it's almost certainly safe or it wouldn't have passed the ethics committee, what you say is an insufficiently detailed description of setup to determine if it's fine or not.

1.2 watts over your entire head is fine.

1.2 watts in a 800nm-diameter cylindrical path is "for some reason we decided to make the outer few millimetres of your skin explode, but we had to be in contact with your skin to manage that because that power density of laser would have ionised the air before it reached you".

Re: Scientists shine a laser through a human head

#15

Post by adolph »

davidmurdoch wrote: post #8
thrance wrote: post #6

Earlier quoted context omitted.

Just make your tinfoil hat a few light-years thick.

You could also wear a black hole as a helmet!

The authors suggest black foamboard with cloth and a laser safety curtain is sufficient. Better safe than sorry though.

  To prevent light from reaching the detector from sources other than light 
  transmitted through the head, the experiment was performed in a light-tight 
  enclosure that surrounded the head. The enclosure was built using black 
  foamboard and covered with two layers of black cloth and a laser safety 
  curtain.
https://doi.org/10.1117/1.NPh.12.2.025014

Re: Scientists shine a laser through a human head

#16

Post by purerandomness »

1970-01-01 wrote: post #7

The 2nd photo is named exactly as it looks; This isn't a parody? https://spectrum.ieee.org/media-library/a-3d-illustration-sh...

It's just SEO.

It's very common to have a CMS feeding images to an LLM that extracts the contents and gives image files a meaningful file name and alt tag.

Re: Scientists shine a laser through a human head

#18

Post by genocidicbunny »

HelloUsername wrote: post #4

The title made me think of Anatoli Bugorski, a Soviet scientist who in 1978 survived a high-energy proton beam from a particle accelerator passing through his head. https://en.wikipedia.org/wiki/Anatoli_Bugorski

Interestingly, one of the things studied at the institute where this happened is proton therapy.

Re: Scientists shine a laser through a human head

#19

Post by short_sells_poo »

echelon wrote: post #9

There have to be ways of getting high space and time resolution signal capable of reconstructing people's exact thoughts, memories, and senses. Non-invasively. No "below threshold of detection". Beyond anything our scientists say is possible. We're just not advanced enough as a species to do it yet. We need to keep pushing these boundaries.

This would likely require completely new forms of physics and interacting with matter I'm afraid. It simultaneously requires extremely high resolution and high penetration (we need to see deep into the brain). You'll need to be able to measure the state of neurons and connections - probably down to the quantum level - and do this real time, and then record the data that you collected.

I suppose you could flood the brain with nano-machines which would latch onto all the bits and pieces and collect the data? But where would they store it? How would we get them all back out again?

I don't think it's possible to do this with our current understanding of physics. This is not a question of needing better technology, but needing a whole new universe with different physics altogether.

I'm not even sure what is more far fetched, this or superluminal travel. I'm actually leaning towards the former :D

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