Fringe | Season 4 | Episode 6 | “And Those We’ve Left Behind”
A well-meaning scientist creates a basement-dwelling machine that allows him to briefly go back in time and hang out with his now-dementia-suffering wife. Of course, this has many unintended consequences and it’s up to our Universe-hopping team to fix it.
Several other posters have pointed out some films/shows with similar themes (principally Stargate SG1 and Groundhog Day), but the first reference that came to me was an episode of Angel where a scientist tries to stop time in order to prevent his girlfriend from breaking up with him (Happy Anniversary; season 2, episode 13).
Walter’s device for detecting “chemical signatures” is probably some kind of fluorescence meter, perhaps calibrated to detect wavelengths specific to certain chemical compounds. However, there would be no way to differentiate between a chemical of interest and another one that happened to fluoresce at the same wavelength.
Alpha radiation is a term used to describe a free-moving helium nucleus (two protons and two neutrons), usually one that is emitted in radioactive decay. “Heightened levels” of this radiation would necessitate dosimeters and breathing masks, making Peter’s grabbing of a Geiger counter a little cavalier.
On a similar theme, neutron radiation is highly dangerous, and if Peter suspected it (his Geiger counter was clicking alarmingly) he really should not have put his hand through a radioactive car bumper. Neutron degradation of metals, though, is a well-known effect (but most modern cars have bumpers made of plastic – I would have checked what model the teenagers were driving if it had been identifiable; perhaps no car manufacturer wants to be associated with bumpers that crumble when irradiated).
The phrase “we need someone with a science background” is always right.