Incoming links: X-ray
100 Greatest Discoveries by the Discovery Channel (2004-2005) Updated 2025-05-23 +Created 1970-01-01
Hosted by Bill Nye.
Physics topics:
- Galileo: objects of different masses fall at the same speed, hammer and feather experiment
- Newton: gravity, linking locally observed falls and the movement of celestial bodies
- TODO a few more
- superconductivity, talk only at Fermilab accelerator, no re-enactment even...
- quark, interview with Murray Gell-Mann, mentions it was "an off-beat field, one wasn't encouraged to work on that". High level blablabla obviously.
- fundamental interactions, notably weak interaction and strong interaction, interview with Michio Kaku. When asked "How do we know that the weak force is there?" the answer is: "We observe radioactive decay with a Geiger counter". Oh, come on!
biology topics:
- Leeuwenhoek microscope and the discovery of microorganisms, and how pond water is not dead, but teeming with life. No sample of course.
- 1831 Robert Brown cell nucleus in plants, and later Theodor Schwann in tadpoles. This prepared the path for the idea that "all cells come from other cells", and the there seemed to be an unifying theme to all life: the precursor to DNA discoveries. Re-enactment, yay.
- 1971 Carl Woese and the discovery of archaea
Genetics:
- Mendel. Reenactment.
- 1909 Thomas Hunt Morgan with Drosophila melanogaster. Reenactment. Genes are in Chromosomes. He observed that a trait was linked to sex, and it was already known that sex was related to chromosomes.
- 1935 George Beadle and the one gene one enzyme hypothesis by shooting X-rays at bread mold
- 1942 Barbara McClintock, at Cold Spring Harbor Laboratory
- 1952 Hershey–Chase experiment. Determined that DNA is what transmits genetic information, not protein, by radioactive labelling both protein and DNA in two sets of bacteriophages. They observed that only the DNA radioactive material was passed forward.
- Crick Watson
- messenger RNA, no specific scientist, too many people worked on it, done partially with bacteriophage experiments
- 1968 Nirenberg genetic code
- 1972 Hamilton O. Smith and the discovery of restriction enzymes by observing that they were part of anti bacteriophage immune-system present in bacteria
- alternative splicing
- RNA interference
- Human Genome Project, interview with Craig Venter.
Medicine:
- blood circulation
- anesthesia
- X-ray
- germ theory of disease, with examples from Ignaz Semmelweis and Pasteur
- 1796 Edward Jenner discovery of vaccination by noticing that cowpox cowpox infected subjects were immune
- vitamin by observing scurvy and beriberi in sailors, confirmed by Frederick Gowland Hopkins on mice experiments
- Fleming, Florey and Chain and the discovery of penicillin
- Prontosil
- diabetes and insulin
Not only did this open the way for X-ray crystallography, it more fundamentally clarified the nature of X-rays as being electromagnetic radiation, and helped further establish the atomic theory.
Find the most interesting research topic that no one is researching Updated 2025-05-23 +Created 2024-12-23
Some cases:
- Marie Curie according to Video "Marie Curie section of The Mystery of Matter episode 2" at youtu.be/wbuDmY5gpXQ?t=2041 she specifically avoided more generic X-ray research, and went instead for radioactivity
How MRI Works Part 1 by thePIRL (2018)
Source. - youtu.be/TQegSF4ZiIQ?t=326 the magnet is normally always on for the entire lifetime of the equipment!
- youtu.be/TQegSF4ZiIQ?t=465 usage of non-ionizing radiation (only radio frequencies) means that it is very safe to use. The only dangerous part is the magnetic field interacting with metallic objects.
Dr Mansfield's MRI MEDICAL MARVEL by BBC
. Source. Broadcast in 1978. Description:Tomorrow's World gave audiences a true world first as Dr Peter Mansfield of the University of Nottingham demonstrated the first full body prototype device for Magnetic resonance imaging (MRI), allowing us to see inside the human body without the use of X-rays.
Like all big names in science, she was at the right place at the right time and with the right interest and passion.
Notably, the man she married, Pierre Curie, happened to be a the world master at precisely the technique that she needed to carefully measure radioactivity: he had the most precise electrometers in the world, which allowed to detect small amounts of radioactivity via the ionization of air by radiation . These used piezoelectricity, which Pierre Curie co-discovered with his brother.
Most important application: produce X-rays for X-ray crystallography.
Note however that the big experiments at CERN, like the Large Hadron Collider, are also synchrotrons.
List of facilities: en.wikipedia.org/wiki/List_of_synchrotron_radiation_facilities
William Coolidge explains medical imaging and X-rays (1940).
Source. Video sponsored by General Electric. A cool insight of this video is that a hot cathode is a more reliable electron source. Previous systems, and presumably including the discovery of X-rays, leftover gas in the tube was used. But this makes things more difficult to control, as we also want to remove as much gas as possible from the vacuum, otherwise electrons collide with the gas and lose energy before hitting the anode.How Does X ray Tube Works by BiomedEngg
. Source. Describes in particular the rotating cathode method. Interesting observation that this is especially important since the cathode cannot cool quickly due to the vacuum.