On Thursday, August 21, 2025 at 5:05:59 AM UTC-6 John Clark wrote:
On Wed, Aug 20, 2025 at 5:22 PM Alan Grayson <[email protected]> wrote: *>> If expanding space can't lengthen the wave length of light then what does "expanding space" even mean? What is causing the cosmological red shift that we observe? Why do objects that are at a larger distance from the Earth have greater red shifts? * *> The wave length of light? When you admit you have at best a very imprecise definition of this concept, some progress might be possible. But not until then. AG * *The wavelength of light (electromagnetic waves) produced by a microwave oven is defined as twice the distance between two melted points of a chocolate bar that had been heated in a microwave oven that was on a non-rotating plate. It works because the microwaves are in a box so they form a standing wave pattern inside the oven, and the waves interfere constructively every half wavelength and produce more heating at that point. **If you actually perform that experiment you'll find that the wavelength is 12.2 cm. * How do you get a definite wave length using the ends of a chocolate bar if you don't know its length? AG *If you find that definition is still "at best very imprecise" perhaps you could give me a better definition of "at best very imprecise" so I could give you a definition that was a bit better than at best less very imprecise.* *Incidentally you can use that same experiment to measure the speed of light, if you happen to know that all household microwave ovens operate at a frequency of 2.45 GHz, by using the simple formula c = fλ (where c is the speed of light, f is frequency, and λ is wavelength).* *John K Clark See what's on my new list at Extropolis <https://groups.google.com/g/extropolis>* The issue I have been discussing applies to quantum light particles called photons. I don't have a problem with classical waves. AG -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/everything-list/767b6c0f-5956-4824-a4b8-8ec43de7e758n%40googlegroups.com.
